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Mellyanawaty, Melly, Firda Mahira Alfiata Chusna, and Estin Nofiyanti. "Proses Peruraian Anaerobik Palm Oil Mill Effluent dengan Media Zeolit Termodifikasi." Jurnal Rekayasa Proses 13, no. 1 (July 1, 2019): 16. http://dx.doi.org/10.22146/jrekpros.39206.
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A B S T R A C TThis work evaluated the effect of modified zeolite as microbial immobilization medium in anaerobic digestion of palm oil mill effluent (POME). The affinity of microorganisms to attach and grow on the media surface could be increased by the addition of micro-nutrient into the media. The effect of micro-nutrient addition was studied in 1000 mL Erlenmeyer flask as batch reactors. Experiments were conducted for 30 days. The concentration of soluble chemical oxygen demand (COD) in substrate was 8000 mg/L. Zeolite was impregnated with nickel (Ni) and zinc (Zn) at individual concentration of 2.7x10-3 mg Ni/g zeolite and 3.5x10‑3 mg Zn/g zeolite. The influence of each modified zeolite was determined by periodic measurement of sCOD, volatile fatty acid (VFA), pH, and biogas production. Cumulative biogas productions in this study were 252.44; 172.13; 57.70 ml from Ni-modified, Zn-modified and natural zeolites, respectively. The highest sCOD removal was obtained in reactor with Zn-modified zeolite with 38.22% removal, followed by 33.96% with Ni-modified zeolite, and 27.87% removal with natural zeolite.Keywords: anaerobic digestion; biogas; methane; palm oil mill effluent; zeoliteA B S T R A KPenelitian ini mengevaluasi pengaruh zeolit yang dimodifikasi sebagai media imobilisasi mikroorganisme pada proses anaerobik limbah palm oil mill effluent (POME). Afinitas mikroorganisme untuk melekat dan tumbuh di permukaan dapat meningkat dengan impregnasi mikronutrien pada media. Efek penambahan mikronutrien dipelajari dengan labu Erlenmeyer 1000 mL sebagai reaktor batch. Experimen dijalankan selama 30 hari. Konsentrasi soluble chemical oxygen demand (sCOD) substrat yang digunakan adalah 8000 mg/L. Zeolit terimpregnasi Ni dan Zn yang digunakan memiliki kadar 2,7 x10-3 mg Ni/g zeolit dan 3,5x10-3 mg Zn/g zeolit. Pengaruh setiap zeolit yang dimodifikasi dievaluasi dengan mengukur konsentrasi sCOD, volatile fatty acid (VFA), pH, dan produksi biogas secara periodik. Akumulasi biogas penelitian ini sebesar 252,44; 172,13; 57,70 ml berturut-turut untuk zeolit modifikasi Ni, zeolit modifikasi Zn dan zeolit alam. Penurunan sCOD terbaik dihasilkan oleh zeolit termodifikasi Zn dengan nilai 38,22%, selanjutnya diikuti oleh zeolit termodifikasi Ni dan zeolit alam dengan nilai 33,96% dan 27,87%.Kata kunci: anaerobic digestion; biogas; metana; palm oil mill effluent; zeolit
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Sugiarti, Sri, Charlena Charlena, and Nurul Afiati Aflakhah. "Zeolit Sintetis Terfungsionalisasi 3-(Trimetoksisilil)-1-Propantiol sebagai Adsorben Kation Cu(II) dan Biru Metilena." Jurnal Kimia VALENSI 3, no. 1 (May 31, 2017): 11–19. http://dx.doi.org/10.15408/jkv.v3i1.5144.
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The more commonly used method for making synthetic zeolite from kaolin is hydrothermal method. This research tested a sol-gel method in processing synthetic zeolit using kaolin as the basic ingrediant. The synthetic zeolite derived from the sol-gel method was then characterized using X-ray Difractometer and Scanning Electron Microscope, which found resulting products zeolite-A, zeolite Y and sodalite. The adsorption ability of the synthetic zeolites was tested using Cu(II) and methylene blue. Functionalization of the synthetic zeolites by 3-(trimetoksisilil)-1-propantiol was done to increase adsorption capacity. Zeolite A modified by 3-(trimetoksisilil)-1-propantiol had the greater capacity to adsorb methylene blue at 30.11 mg/g. The adsorption isotherms of all the synthetic zeolites approached the Langmuir form. The adsorption energy off all synthetic zeolites approached the chemical adsorption.DOI: http://dx.doi.org/10.15408/jkv.v0i0.5144
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Elysabeth, Tiur, Zulnovri, Gina Ramayanti, Setiadi, and Slamet. "Modification of Lampung and Bayah Natural Zeolite to Enhance the Efficiency of Removal of Ammonia from Wastewater." Asian Journal of Chemistry 31, no. 4 (February 27, 2019): 873–78. http://dx.doi.org/10.14233/ajchem.2019.21810.
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In this research, modification of Lampung and Bayah natural zeolites was carried out to increase the zeolite’s capacity as an ammonia adsorbent. Natural zeolite is modified by acid treatment using 6 M HCl and ion exchange using 1 M NH4NO3. The modification process continued with calcination at 500 °C for 4 h. X-ray fluorescence characterization shows changes in composition in the modified zeolites. The significant increase in the Si/Al ratio occurred in the modified zeolite with acid treatment that is 10.03 for Lampung natural zeolite HCl (LNZH) and 9.20 for Bayah natural zeolite HCl (BNZH). Surface area increases due to increasing Si/Al ratio. FTIR results indicate changes in the intensity of hydroxyl groups and pyrH+ as a result of the increase in total acidity of zeolites. The zeolites performance test proves that the Bayah natural zeolite has a higher ammonia adsorption capacity than Lampung natural zeolite. Ion exchange-modified zeolite has a higher ammonia adsorption capacity than zeolite modified with acid treatment.
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Hakiki, Muhammad, Muhammad Makiyi, Nuryoto Nuryoto, Rahmayetty Rahmayetty, Indar Kustiningsih, and Teguh Kurniawan. "Pengaruh Lokasi Zeolit Alam Bayah terhadap Adsorpsi Amonium: Studi Kinetika dan Kesetimbangan." Jurnal Teknologi Lingkungan 22, no. 1 (February 3, 2021): 018–28. http://dx.doi.org/10.29122/jtl.v22i1.4403.
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ABSTRACT Household waste is one of the most significant contributors to wastewater that can pollute the environment, one of which is ammonium pollution. Ammonium pollution can be reduced by natural zeolite by using the adsorption method. This research aims to utilize natural zeolite as an adsorbent that can reduce ammonium levels in wastewater, determine which natural zeolite has the most significant adsorption power from 4 locations, determine natural zeolite characterization of Bayah. This study is also to create a model equilibrium equations and reaction kinetics from the adsorption method. The method used is the adsorption method, X-ray diffraction (XRD), Scanning Electron Microscope (SEM), and Brunauer-Emmett-Teller (BET). This study's results were that natural zeolites location 4 could adsorb 99.25% of ammonium and showed the highest adsorption capacity of ammonium. Characterization using XRD analysis obtained the types of zeolite mordenite, clinoptilolite, quartz, and heulandite. The surface area of Bayah natural zeolite in the 4th location is 46 m2/g. The suitable equilibrium model for the adsorption of ammonium by natural zeolites is the Freundlich model. The most suitable adsorption kinetics model for the adsorption of ammonium by Bayah natural zeolites is the pseudo-first-order model. Keywords: household waste, ammonium, eutrophication, natural zeolites ABSTRAK Limbah rumah tangga adalah salah satu penyumbang limbah cair terbesar yang dapat mencemari lingkungan salah satunya pencemaran amonium. Pencemaran amonium dapat dikurangi dengan zeolit alam dengan menggunakan metode adsorpsi. Tujuan dari penelitian ini adalah menentukan zeolit alam yang memiliki daya adsorpsi terbesar dari 4 lokasi berbeda, melakukan karakterisasi zeolit alam Bayah, dan memodelkan persamaan kesetimbangan dan kinetika reaksi adsorpsi amonium. Karakterisasi zeolit dilakukan dengan analisis X-ray diffraction (XRD), Scanning Electron Microsope (SEM), dan luas permukaan material menggunakan model Brunauer-Emmett-Teller (BET). Hasil dari penelitian ini adalah zeolit alam lokasi 4 memiliki kapasitas adsorpsi amonium paling besar, yaitu 9,25%. Adapun kapasitas adsorpsi amonium yang paling besar ditunjukkan oleh zeolit alam Bayah lokasi 4. Analisis XRD menunjukkan bahwa seluruh zeolit Bayah merupakan zeolit bertipe mordenit, klinoptilolit, dan heulandit dengan fasa pengotor quartz. Luas permukaan zeolit alam Bayah lokasi 4 sebesar 46 m2/g. Model kesetimbangan yang sesuai untuk adsorpsi amonium oleh zeolit alam Bayah yaitu model Freundlich. Model kinetika adsorpsi yang paling sesuai untuk adsorpsi amonium oleh zeolit alam Bayah yaitu model kuasi orde satu. Kata Kunci: limbah rumah tangga, amonium, eutrofikasi, zeolit alam
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Kalista, Nadia Nanda, Rahmana Emran Kartasasmita, Marlia Singgih Wibowo, and Lenny Marilyn Estiaty. "KARAKTERISASI DAN PEMURNIAN ZEOLIT ALAM LAMPUNG SEBAGAI KANDIDAT ANTIDOTUM KERACUNAN TIMBAL." Acta Pharmaceutica Indonesia 42, no. 2 (December 27, 2017): 84–91. http://dx.doi.org/10.5614/api.v42i2.5656.
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Indonesia memiliki kelimpahan zeolit yang berpotensi dapat dikembangkan sebagai zeolit yang berderajat farmasi. Penelitian ini bertujuan untuk mendapatkan zeolit olahan dengan karakteristik yang cocok sebagai bahan baku farmasi. Zeolit alam diproses dengan cara pencucian menggunakan masing-masing larutan HCl, aquabidest, dan EDTA lalu diikuti dengan pemanasan pada 350 °C. Sebelum dan sesudah pengolahan sampel zeolit dikarakterisasi menggunakan berbagai metode instrumental. Selanjutnya, zeolit olahan diuji kemampuannya untuk menjerap parasetamol dan timbal. Hasil analisis menunjukkan bahwa komposisi sampel zeolit > 91% berjenis klinoptilolit dengan kandungan utama unsur Si, Al dan K. Setelah pencucian dengan larutan HCl 1 M, EDTA 0,1 M dan aquabidest, kadar As dalam masing-masing sampel zeolit 4,12 ± 0,75 ppm, < 0,1 ppm dan 11,8 ± 0,56 ppm dan kadar Pb untuk seluruh sampel < 1 ppm, sedangkan Cd dari semua sampel < 1 ppm. Tidak ada perubahan struktur dalam sampel zeolit yang teramati setelah proses pencucian dan pemanasan. Zeolit yang dicuci dengan larutan EDTA mampu menjerap Pb dalam cairan lambung buatan tanpa pepsin secara efektif dengan penurunan kadar hingga 89% namun tidak mampu menjerap parasetamol secara efektif. Disimpulkan bahwa hasil proses zeolit menunjukkan karakteristik yang cocok sebagai kandidat bahan baku farmasi. Zeolit yang diberi perlakuan dengan EDTA mampu menjerap Pb secara efektif sehingga berpeluang digunakan sebagai antidot lokal dalam kasus keracunan Pb akut.Kata kunci: zeolit, klinoptilolit, logam berat. CHARACTERIZATION AND PURIFICATION OF NATURAL LAMPUNG ZEOLITE AS A CANDIDATE OF ANTIDOTE OF LEAD INTOXICATIONABSTRACTIndonesia has the abundance potential of zeolites having possibility to be developed as pharmaceutical grade zeolites. This research aimed to obtain processed zeolite showing suitable characteristics as pharmaceutical ingredient. Natural zeolite was processed by means of washing using dilute HCl, aquabidest and EDTA solutions, respectively and subsequently followed by heating at 350 oC. Prior and after processing, the zeolite samples were characterized using various instrumental methods. Furthermore, the processed zeolite was tested for its ability to adsorb paracetamol and lead. The analysis results confirmed that the composition of zeolite samples were > 91% of clinoptilolite mainly composed of Si, Al and K. After washing with 1 M HCl, 0.1 M EDTA and aquabidest, the level of As in each of zeolite samples were 4.12 ± 0.75 ppm, < 0.1 ppm and 11.8 ± 0.56 ppm and those of Pb were all < 1 ppm, while those of Cd from all samples were < 1 ppm, respectively. No structural changes in zeolite samples were observed after washing and heating treatment. EDTA treated zeolite was able to adsorb Pb in artificial gastric fluid without pepsin effectively up to 89% reduction but failed to adsorb paracetamol effectively. It was concluded that processed natural zeolite was suitable as a pharmaceutical ingredient. EDTA-treated zeolite was able to adsorb Pb effectively and hence could be possibly applied as local antidote in the case of acute Pb intoxication.Keywords: zeolite, clinoptilolite, heavy metals.
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Nursanti, Ida, and Nida Kemala. "Peranan Zeolit dalam Peningkatan Kesuburan Tanah Pasca Penambangan." Jurnal Media Pertanian 4, no. 2 (November 11, 2019): 88. http://dx.doi.org/10.33087/jagro.v4i2.84.
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ABSTRACTPost-mining soils have poor chemical and physical properties and have very low fertility rates. The study aims to determine the best dose of zeolite in order to improve soil fertility after mining as a planting medium. The experiment was carried out experimentally by giving zeolites (Z) and 3 treatment levels, namely: Z0 = without zeolites, Z1 = zeolites 100 g, Z2 = zeolites 200 g. There were 3 replications, so 9 unit experiments were obtained. The final analysis of research on soil chemistry consists of; Available P, total N, K-exs, C-organic and CEC, pH. Data analysis of the diversity of characteristics of post-mining soil types is presented in tabular form and discussed descriptively. Provision of 200 grams zeolite of 10 kg post-mining land (equivalent to 20 tons Ha-1 of zeolite ) and incubated for eight weeks can increase soil pH, total N, K-dd, available P andCECsoil. Keywords: Zeolites and post-mining soils ABSTRAKTanah pasca penambangan memiliki sifat kimia dan fisik yang kurang baik serta memiliki tingkat kesuburan yang sangat rendah. Penelitian bertujuan mengetahui menentukan dosis zeolit terbaik agar dapat memperbaiki kesuburan tanah pasca penambangan terkait sebagai media tanam. Percobaan dilakukan secara eksperimen dengan pemberian zeolit (Z) dan 3 taraf perlakuan yaitu :Z0= tanpa zeolit, Z1 = zeolit 100 g, Z2 = zeolit 200 g. Terdapat 3 ulangan, sehingga diperoleh 9 unit percobaan. Analisis akhir penelitian terhadap kimia tanah terdiri dari; P tersedia, N total, K-dd, C-organik dan KTK, pH. Analisis data keragaman karakteristik jenis tanah pasca penambangan disajikan dalam bentuk tabel dan dibahas secara deskriptif. Pemberian zeolit 200 gram per 10 kg tanah pasca tambang (setara 20 ton zeolit per Ha) dan diinkubasi selama delapan minggu dapat meningkatkan pH tanah, N-total, K-dd, P tersedia dan KTK tanah. Kata kunci : Zeolit dan tanah pasca penambangan.
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Purnamaningsih, Nur'aini, Endah Retnaningrum, and Wahyu Wilopo. "PEMANFATAAN KONSORSIUM BAKTERI PEREDUKSI SULFAT DAN ZEOLIT ALAM DALAM PENGENDAPAN LOGAM Mn." Jurnal Penelitian Saintek 22, no. 1 (August 28, 2017): 37. http://dx.doi.org/10.21831/jps.v22i1.15311.
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Tujuan dari penelitian ini adalah untuk mengetahui pengaruh penambahan zeolit alam Wonosari terhadap aktivitas Bakteri Pereduksi Sulfat dalam pengendapan logam Mn skala continous culture dan mengidentifikasi karakter biofilm Bakteri Pereduksi Sulfat oleh aktivitas konsorsium Bakteri Pereduksi Sulfat pada zeolit alam dalam skala continous culture. Tahap penelitian meliputi aktivasi zeolit, pengujian aktivitas konsorsium Bakteri Pereduksi Sulfat dalam skala continous culture; serta karakterisasi biofilm konsorsium Bakteri Pereduksi Sulfat. Konsorsium Bakteri Pereduksi Sulfat yang digunakan berasal dari kotoran kambing. Zeolit yang digunakan pada pengujian aktivitas konsorsium Bakteri Pereduksi Sulfat adalah zeolit alam Wonosari yang berukuran 0,8-1,2 cm. Hasil penelitian menunjukkan bahwa konsorsium Bakteri Pereduksi Sulfat pada bioreaktor dengan penambahan zeolit mempunyai aktivitas yang lebih efektif dibandingkan dengan bioreaktor tanpa penambahan zeolit, dimana pH meningkat menjadi pH 6,9; efisiensi pengendapan logam Mn sebesar 61,16%, serta nilai MPN yang lebih tinggi. Zeolit dalam bioreaktor dengan waktu pembentukan biofilm 5 hari dan 9 hari terlihat adanya biofilm konsorsium Bakteri Pereduksi Sulfat yang tumbuh melekat pada permukaan zeolit. The objective of this study were determining the effects of natural zeolite from Wonosari on the activites of Sulfate Reducing Bacteria in Mangan (Mn) sedimentation of continous culture scale, and identifying the biofilm character of Sulfate Reducing Bacteria on consortium activites on natural zeolite using continous culture scale. The first studies was activation of zeolites, followed by testing the activity of consortium activities of Sulfate Reduction Bacteria in continuous culture scales; and biofilm characterization of Sulfate Reducing Bacteria consortium. The consortium of Sulfate Reducing Bacteria derived from goat feces. The size of zeo natural zeolites used in the consortium activity test of Sulfate Reducing Bacteria in Mangan sedimentation was 0.8 to 1.2 cm. The results showed that the consortium of Sulfate Reducing Bacteria in the bioreactor with the addition of zeolite had an activity that was more effective than the bioreactor without the addition of zeolite, where the pH was increased to pH 6.9; Mangan sedimentation was 61,16%, and the higher MPN index. Zeolite in a bioreactor with biofilm formation in 5th days and 9th days seems that there were biofilm consortium of Sulfate Reducing Bacteria growing attached to the surface of the zeolite.
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Rentsenorov, Ulambayar, Batmunkh Davaabal, and Jadambaa Temuujin. "Synthesis of Zeolite A from Mongolian Coal Fly Ash by Hydrothermal Treatment." Solid State Phenomena 271 (January 2018): 1–8. http://dx.doi.org/10.4028/www.scientific.net/ssp.271.1.
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Raw coal fly ash and acid pretreated fly ash were used to synthesize A-type zeolite by hydrothermal treatment. In order to synthesize zeolite A an aqueous gel having a molar batch composition of Na2O:Al2O3:1.926SiO2:128H2O was utilized. Fly ash and zeolitic products were characterized by SEM, XRF, XRD and cation exchange capacity (CEC). After hydrothermal treatment, several types of zeolites were formed: zeolite A, analcime, faujasite and hydroxy-sodalite. The highest content of zeolite A was formed in the mixture treated at 80°C for 8 hours. CEC values of the zeolitic products were 28-38 times higher than that of in raw fly ash. Acid pretreatment which leads to low calcium and iron content is preferable method for processing of fly ash for the zeolite synthesis. Synthesized zeolite can be used for ion exchangers for water treatment.
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Trivana, Linda, Sri Sugiarti, and Eti Rohaeti. "SYNTHESIS OF ZEOLITE AND COMPOSITE OF ZEOLITE/TiO2 FROM KAOLIN AND ITS APLICATION TO ADSORPTION-PHOTODEGRADATION OF METHILEN BLUE." ALCHEMY Jurnal Penelitian Kimia 11, no. 2 (September 27, 2016): 147. http://dx.doi.org/10.20961/alchemy.11.2.722.147-162.
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<p>In this study, zeolite was synthesized from kaolin which was founded from Bangka Belitung as the starting material. Meanwhile, sodium silicate was used as silica source. Zeolite is material with many benefits, such as become an adsorbent. Kaolin has been used as starting material due to high content of silica and alumina, i.e 35 - 50 %. Zeolite was prepared by hydrothermal synthesis process, by mixing the metakaolin which was produced by calcination of kaolin at 700 °C for 6 hours, with sodium silicate and NaOH. The NaOH was used to activate the major components of Si and Al in the kaolin.The hydrothermal process was conducted at 100 °C for 24 hours with various concentrations of NaOH, i.e 1.5 N and 2.5 N. The NaOH concentration might determine the type of zeolite obtained. To improve the nature as adsorbent, zeolites modified into zeolit/TiO<sub>2</sub>. The addition of TiO<sub>2</sub>into the prepared zeolit aimed to produce a material with capability as adsorbent-photocatalyst. The result of research found that the addition of NaOH 1.5 N produced zeolite NaP1. Meanwhile, the addition of NaOH 2.5 N produced the NaP1 zeolite, zeolite X, and faujasite. The composite of zeolit/TiO<sub>2</sub>has ability on adsorption-photocatalytic as it was proven by methylene blue degradation under ultraviolet light.</p>
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Trivana, Linda, Sri Sugiarti, and Eti Rohaeti. "SYNTHESIS OF ZEOLITE AND COMPOSITE OF ZEOLITE/TiO2 FROM KAOLIN AND ITS APLICATION TO ADSORPTION-PHOTODEGRADATION OF METHILEN BLUE." ALCHEMY Jurnal Penelitian Kimia 11, no. 2 (September 27, 2016): 147. http://dx.doi.org/10.20961/alchemy.v11i2.722.
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<p>In this study, zeolite was synthesized from kaolin which was founded from Bangka Belitung as the starting material. Meanwhile, sodium silicate was used as silica source. Zeolite is material with many benefits, such as become an adsorbent. Kaolin has been used as starting material due to high content of silica and alumina, i.e 35 - 50 %. Zeolite was prepared by hydrothermal synthesis process, by mixing the metakaolin which was produced by calcination of kaolin at 700 °C for 6 hours, with sodium silicate and NaOH. The NaOH was used to activate the major components of Si and Al in the kaolin.The hydrothermal process was conducted at 100 °C for 24 hours with various concentrations of NaOH, i.e 1.5 N and 2.5 N. The NaOH concentration might determine the type of zeolite obtained. To improve the nature as adsorbent, zeolites modified into zeolit/TiO<sub>2</sub>. The addition of TiO<sub>2</sub>into the prepared zeolit aimed to produce a material with capability as adsorbent-photocatalyst. The result of research found that the addition of NaOH 1.5 N produced zeolite NaP1. Meanwhile, the addition of NaOH 2.5 N produced the NaP1 zeolite, zeolite X, and faujasite. The composite of zeolit/TiO<sub>2</sub>has ability on adsorption-photocatalytic as it was proven by methylene blue degradation under ultraviolet light.</p>
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Barbosa, Tellys Lins Almeida, and Meiry Gláucia Freire Rodrigues. "Synthesis of SAPO-34 Zeolite Membrane: Influence of Sources of Silica." Catalysis Research 03, no. 04 (December 11, 2023): 1–19. http://dx.doi.org/10.21926/cr.2304030.
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The research described the production and characterization of various materials, particularly alpha-alumina ceramic supports, zeolite SAPO-34, and zeolite membranes. Ceramic supports were manufactured through dry uniaxial compaction. Sintering of the supports was carried out at 1300°C for 2 h. SAPO-34 zeolites and zeolite membranes were synthesized through a hydrothermal process involving two steps: a first step at 38°C for 24 h and a second step at 200°C for 24 h. The research aimed to determine how different silica sources, namely Aerosil 380, colloidal silica, and TEOS, influenced the outcome of the synthesis. The study identified that Aerosil 380 silica was the most suitable source for synthesizing SAPO-34 zeolites and membranes. Zeolite membranes (SAPO-34/alpha-alumina) displayed a uniform and homogeneous distribution of SAPO-34 phase zeolitic crystals. The absence of defects or cracks in these membranes confirmed the successful formation of the SAPO-34 zeolite membrane structure. This research has significant implications, particularly in materials science and applications utilizing zeolites and membranes. The choice of silica source plays a crucial role in determining the quality and properties of the synthesized materials, and the detailed characterization provides valuable insights into their performance in practical applications. Overall, the research contributes to the understanding and optimization of zeolite synthesis processes.
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Azizi, Seyed Naser, Akram Alavi Daghigh, and Maryam Abrishamkar. "Phase Transformation of Zeolite P to Y and Analcime Zeolites due to Changing the Time and Temperature." Journal of Spectroscopy 2013 (2013): 1–5. http://dx.doi.org/10.1155/2013/428216.
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In the present study, the synthesis of template free zeolite P under hydrothermal condition was investigated. The effects of parameters such as Si/Al ratios (3–45), crystallization temperatures (80–160°C), and cry (40–60 h) on the synthesis of zeolite P were studied. The phase transformation of zeolite P to two types of high crystallinity Y and analcime zeolites due to change of temperature was observed. The effect of temperature on the achievement of two different zeolite types (Y and analcime) with a constant initial synthetic composition under organic free synthesis of zeolite P was studied. The zeolitic products were characterized by X-ray diffraction, scanning electron microscopy, and IR spectroscopy techniques.
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Qiu, Liyan, Patricia A. Laws, Bi-Zeng Zhan, and Mary Anne White. "Thermodynamic investigations of zeolites NaX and NaY." Canadian Journal of Chemistry 84, no. 2 (February 1, 2006): 134–39. http://dx.doi.org/10.1139/v05-244.
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Understanding of the thermodynamic stability of zeolites is important in the prediction of thermodynamic equilibrium. Therefore, we have undertaken an investigation of the thermodynamic stability of the zeolites NaX and NaY through heat capacity measurements from ca. 30 to 300 K. No phase transitions were observed, and zeolite NaX does not show a significant particle size effect when the particle size is reduced to ca. 30 nm. The results show that the specific heat capacity increases with the Al content in the zeolite. Both NaX and NaY are found to be thermodynamically stable with respect to their elements because of enthalpic stabilization and with slight entropic destabilization. These data are used along with literature data for many other zeolitic materials to show that the thermodynamic stability of zeolites is enhanced with increasing aluminum content. Key words: zeolite, heat capacity, thermodynamic stability, nano effects.
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Murrieta-Rico, Fabian N., Joel Antúnez-García, Rosario I. Yocupicio-Gaxiola, Armando Reyes Serrato, Vitalii Petranovskii, Mufei Xiao, Oleg Sergiyenko, Wendy Flores-Fuentes, and Julio C. Rodríguez-Quiñonez. "Frequency Response Analysis of FAU, LTA and MFI Zeolites Using UV-Vis and Electrochemical Impedance Spectroscopy." Optics 4, no. 3 (July 28, 2023): 459–72. http://dx.doi.org/10.3390/opt4030033.
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Zeolites are porous materials that have cavities interconnected by channels. These crystalline materials are composed of Si-O tetrahedral structures, and according to the assembly of such tetrahedral structures, specific crystalline structures are obtained. Until now, it has been said that there are more than 245 different zeolitic frameworks, and since each one has a specific distribution of pores and cavities, each kind of zeolite has a specific area-to-volume ratio. As a result of the type of zeolite structure, the zeolite can exhibit specific properties, i.e., electrical or optical. Moreover, the physical properties of zeolites can be modified after the inclusion of another chemical species in their structure or in their voids, which can result in tuning a zeolite for specific applications. In this work, synthetic zeolites of types LTA, FAU and MFI are characterized by a number of methods. In particular, the data from UV-Vis spectroscopy are analyzed, and the effect of crystalline structure on properties such as optical bandgap, refractive index, absorption coefficient, incident photon frequency, and extinction coefficient is studied.
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Li, Laura Jiaxuan, Chun-Hung Chu, and Ollie Yiru Yu. "Application of Zeolites and Zeolitic Imidazolate Frameworks in Dentistry—A Narrative Review." Nanomaterials 13, no. 22 (November 18, 2023): 2973. http://dx.doi.org/10.3390/nano13222973.
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Zeolites and zeolitic imidazolate frameworks (ZIFs) are crystalline aluminosilicates with porous structure, which are closely linked with nanomaterials. They are characterized by enhanced ion exchange capacity, physical–chemical stability, thermal stability and biocompatibility, making them a promising material for dental applications. This review aimed to provide an overview of the application of zeolites and ZIFs in dentistry. The common zeolite compounds for dental application include silver zeolite, zinc zeolite, calcium zeolite and strontium zeolite. The common ZIFs for dental application include ZIF-8 and ZIF-67. Zeolites and ZIFs have been employed in various areas of dentistry, such as restorative dentistry, endodontics, prosthodontics, implantology, periodontics, orthodontics and oral surgery. In restorative dentistry, zeolites and ZIFs are used as antimicrobial additives in dental adhesives and restorative materials. In endodontics, zeolites are used in root-end fillings, root canal irritants, root canal sealers and bone matrix scaffolds for peri-apical diseases. In prosthodontics, zeolites can be incorporated into denture bases, tissue conditioners, soft denture liners and dental prostheses. In implantology, zeolites and ZIFs are applied in dental implants, bone graft materials, bone adhesive hydrogels, drug delivery systems and electrospinning. In periodontics, zeolites can be applied as antibacterial agents for deep periodontal pockets, while ZIFs can be embedded in guided tissue regeneration membranes and guided bone regeneration membranes. In orthodontics, zeolites can be applied in orthodontic appliances. Additionally, for oral surgery, zeolites can be used in oral cancer diagnostic marker membranes, maxillofacial prosthesis silicone elastomer and tooth extraction medicines, while ZIFs can be incorporated to osteogenic glue or used as a carrier for antitumour drugs. In summary, zeolites have a broad application in dentistry and are receiving more attention from clinicians and researchers.
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Pansini, Michele, Angelo Cappi, Vincenzo Monetti, Enrico Di Clemente, Maurizio de Gennaro, Marco D’Amore, Rosa Buccino, Pierpaolo Santimone Nuzzi, and Bruno de Gennaro. "Thermodilatometric Study of the Decay of Zeolite-Bearing Building Materials." Materials 14, no. 13 (June 25, 2021): 3551. http://dx.doi.org/10.3390/ma14133551.
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Six zeolite-bearing rocks, often used as building materials, were analyzed by thermodilatometry, together with a rock not bearing zeolites and a plaster covering a containing wall made of zeolite-bearing dimension stones, up to 250 °C. The main results obtained were the following: (i) the zeolite-bearing rocks exhibited very small, if any, positive variation of ΔL/Lo (%) up to about 100 °C, whereas they more or less shrank in the temperature range 100–250 °C (final values ranging from −0.21 to −0.92%); (ii) the rock not bearing zeolites regularly expanded through the whole temperature range, attaining a final value of 0.19%; (iii) the plaster showed a thermodilatometric behavior strongly affected by its water content. Obtained results were interpreted based on plain thermal expansion, shrinkage by dehydration, cation migration and thermal collapse of the zeolitic structure. The decay of the zeolite-bearing building materials was essentially related to: (i) the large differences recorded in the thermodilatometric behavior of the various rocks and the plaster; (ii) the different minerogenetic processes that resulted in the deposition of the various zeolite-bearing rocks.
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Peng, Peng, Xiong-Hou Gao, Zi-Feng Yan, and Svetlana Mintova. "Diffusion and catalyst efficiency in hierarchical zeolite catalysts." National Science Review 7, no. 11 (August 21, 2020): 1726–42. http://dx.doi.org/10.1093/nsr/nwaa184.
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Abstract The preparation of hierarchical zeolites with reduced diffusion limitation and enhanced catalyst efficiency has become a vital focus in the field of zeolites and porous materials chemistry within the past decades. This review will focus on the diffusion and catalyst efficiency of hierarchical zeolites and industrial catalysts. The benefits of diffusion and catalyst efficiency at two levels of hierarchies (zeolitic component level and industrial catalyst level) from a chemical reaction engineering point of view will be analysed. At zeolitic component level, three types of mesopores based on the strategies applied toward enhancing the catalyst effectiveness factor are presented: (i) ‘functional mesopores’ (raising effective diffusivity); (ii) ‘auxiliary mesopores’ (decreasing diffusion length); and (iii) ‘integrated mesopores’ (a combination thereof). At industrial catalyst level, location and interconnectivity among the constitutive components are revealed. The hierarchical pore interconnectivity in multi-component zeolite based industrial catalysts is exemplified by fluid catalytic cracking and bi-functional hydroisomerization catalysts. The rational design of industrial zeolite catalysts at both hierarchical zeolitic component and catalyst body levels can be fully comprehended using the advanced in situ and/or operando spectroscopic, microscopic and diffraction techniques.
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Mukti, Rino R., Shofarul Wustoni, Agus Wahyudi, and Ismunandar Ismunandar. "CONVERSION OF THE LOW QUALITY INDONESIAN NATURALLY-OCCURRING MINERALS INTO SELECTIVE TYPE OF ZEOLITES BY SEED-ASSISTED SYNTHESIS METHOD." Indonesian Journal of Chemistry 13, no. 3 (December 18, 2013): 278–82. http://dx.doi.org/10.22146/ijc.21288.
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An X-ray diffraction (XRD) revealed that Indonesian naturally-occurring mineral from Nanggung, Bogor shows to be a low quality product as it does not seem to contain any zeolite materials. As located in the volcanic area, Indonesia essentially has abundant source of natural zeolites and the country has put much efforts on these treasured materials for export commodity. In order to bring the local natural mineral into high value and to discover whether the mineral has at least zeolitic fragments, we have implemented seed-assisted synthesis to see the possibility of growing zeolite and turn this mineral into high quality. In principle, once the mineral has zeolitic fragment or nuclei, recrystallization of the mineral may occur. By utilizing this mineral as seed in aluminosilicate mother solution, selective mordenite-type (MOR) zeolite can be obtained after hydrothermal treatment. Characterization by XRD showed that this MOR zeolite has high crystallinity and scanning electron microscopy (SEM) depicted the crystal morphology. The natural mineral is conclusively essential for the formation of MOR zeolite by seeding the aluminosilicate mother solution. In the absence of aluminosilicate mother solution, natural mineral can be recrystallized into selective analcime-type (ANA) zeolite. MOR zeolite is known to be useful for several applications such as catalysis whereas ANA zeolite has been considered to be less potential due to relatively small microporosity.
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Woszuk, Agnieszka. "Application of Fly Ash Derived Zeolites in Warm-Mix Asphalt Technology." Materials 11, no. 9 (August 27, 2018): 1542. http://dx.doi.org/10.3390/ma11091542.
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In recent years, numerous studies have been carried out on new technologies allowing to reduce of mix asphalt production temperatures. One of the possibilities is to foam the asphalt with “water-containing” additives, which include zeolites. So far, mainly synthetic zeolites of the Linde A structure type, obtained from chemical reagents, and natural clinoptilolite have been used in WMA technology. In this studies, the synthetic zeolites produced from fly ashes with 4 different types of crystalline structure were analyzed. Zeolite materials were characterized by textural parameters and thermal analysis. The amount of zeolite added to asphalt was 0, 3, 5, 7 wt % in relation to the weight of asphalt. Determination of dynamic viscosity was performed at two temperatures: 135 and 160 and 4 time intervals. The tests were performed for two asphalt binders: 35/50 and 100/150 penetration grade. As a conclusion, it was found that the viscosity of asphalt pastes with zeolitic materials increases with the increase in the amount of zeolite added. The increase level depends mainly on the textural parameters. The potential usefulness of fly ash derived zeolites in the process of asphalt foaming, which depends mainly on the amount of water contained in the zeolite structure and the method of its release, has been proved.
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Ortega-Aguirre, Samantha, María del Carmen Díaz-Nava, Marcos J. Solache-Ríos, and Javier Illescas. "Alginate-iron modified zeolite beads biocomposite for removal of azo dye from water medium." MRS Advances 3, no. 63 (2018): 3769–73. http://dx.doi.org/10.1557/adv.2018.642.
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ABSTRACTOrganic compounds such as azo dyes have been detected in wastewater due to their use in industries without regulation. Conventional wastewater treatments are not always effective in the removal of these pollutants. Among the innovative materials that deal with this problem, are the polymer-zeolitic composites used as adsorbents. Modified natural zeolites have been proven to be efficient for the removal of yellow 6; on the other hand, biopolymers such as alginate offer their potential use as a polymer matrix for the synthesis of biocomposites. In this study, the adsorbent properties of a ferric zeolite and an alginate-ferric zeolite composite were determined for the removal of yellow 6 dye from aqueous solutions. The X-ray diffraction (XRD) results of both natural and modified zeolites indicated the presence of clinoptilolite. The characteristic bands of these materials were identified through the Fourier Transform Infrared Spectroscopy (FTIR) technique. Moreover, the presence of iron in the ferrous zeolite was verified by elemental analysis (EDS). Adsorption tests showed that the composite has a lower removal capacity than the zeolitic material; however, in the case of water treatment systems, the composite would be easier to handle than the zeolite without supporting it in a polymer matrix.
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Andrades, Raphael Cons, Roberto Freitas Neves, Francisco Rolando Valenzuela Díaz, and Antonio Hortencio Munhoz Júnior. "Influence of Alkalinity on the Synthesis of Zeolite A and Hydroxysodalite from Metakaolin." Journal of Nano Research 61 (February 2020): 51–60. http://dx.doi.org/10.4028/www.scientific.net/jnanor.61.51.
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Kaolin is a cheap and abundant source of silica and alumina, which may be used as precursors for the production of zeolites, molecular sieves with pores in the nanometer scale. Brazil, one the largest producers of kaolin, generates tons of kaolin waste in the paper coating process. That waste may be used to synthesize zeolite A and hydroxysodalite, greater added value materials with a wide range of applications. In this work, Zeolite A and hydroxysodalite were synthesized from kaolin waste of processing industries for paper coating. Kaolin was calcined to dehydroxylate kaolinite and obtain metakaolin, an amorphous material with Si/Al ratio equal to 1, being suitable for production of zeolite A and hydroxysodalite. Zeolites were synthesized under static hydrothermal conditions by reacting metakaolin with NaOH solutions of different concentrations. The zeolitic products were characterized by means of X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The results showed that the higher the NaOH concentration in the reaction medium, the higher the proportion of hydroxysodalite in the zeolitic samples.
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Szatanik-Kloc, Alicja, Justyna Szerement, Agnieszka Adamczuk, and Grzegorz Józefaciuk. "Effect of Low Zeolite Doses on Plants and Soil Physicochemical Properties." Materials 14, no. 10 (May 17, 2021): 2617. http://dx.doi.org/10.3390/ma14102617.
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Thousands of tons of zeolitic materials are used yearly as soil conditioners and components of slow-release fertilizers. A positive influence of application of zeolites on plant growth has been frequently observed. Because zeolites have extremely large cation exchange capacity, surface area, porosity and water holding capacity, a paradigm has aroused that increasing plant growth is caused by a long-lasting improvement of soil physicochemical properties by zeolites. In the first year of our field experiment performed on a poor soil with zeolite rates from 1 to 8 t/ha and N fertilization, an increase in spring wheat yield was observed. Any effect on soil cation exchange capacity (CEC), surface area (S), pH-dependent surface charge (Qv), mesoporosity, water holding capacity and plant available water (PAW) was noted. This positive effect of zeolite on plants could be due to extra nutrients supplied by the mineral (primarily potassium—1 ton of the studied zeolite contained around 15 kg of exchangeable potassium). In the second year of the experiment (NPK treatment on previously zeolitized soil), the zeolite presence did not impact plant yield. No long-term effect of the zeolite on plants was observed in the third year after soil zeolitization, when, as in the first year, only N fertilization was applied. That there were no significant changes in the above-mentioned physicochemical properties of the field soil after the addition of zeolite was most likely due to high dilution of the mineral in the soil (8 t/ha zeolite is only ~0.35% of the soil mass in the root zone). To determine how much zeolite is needed to improve soil physicochemical properties, much higher zeolite rates than those applied in the field were studied in the laboratory. The latter studies showed that CEC and S increased proportionally to the zeolite percentage in the soil. The Qv of the zeolite was lower than that of the soil, so a decrease in soil variable charge was observed due to zeolite addition. Surprisingly, a slight increase in PAW, even at the largest zeolite dose (from 9.5% for the control soil to 13% for a mixture of 40 g zeolite and 100 g soil), was observed. It resulted from small alterations of the soil macrostructure: although the input of small zeolite pores was seen in pore size distributions, the larger pores responsible for the storage of PAW were almost not affected by the zeolite addition.
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Filippidis, A., N. Kantiranis, and A. Tsirambides. "THE MINERALOGICAL COMPOSITION OF THRACE ZEOLITIC ROCKS AND THEIR POTENTIAL USE AS FEED ADDITIVES AND NUTRITION SUPPLEMENTS." Bulletin of the Geological Society of Greece 50, no. 4 (July 28, 2017): 1820. http://dx.doi.org/10.12681/bgsg.14110.
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Thirty two (32) locations of zeolitic rocks from Thrace (29 from Evros prefecture and 3 from Rhodope prefecture) were investigated for their mineralogical composition by X-Ray Diffraction (XRD) method. According to EU Regulation No 651/2013, clinoptilolite of sedimentary origin (zeolitic tuffs) with ≥80 wt% clinoptilolite, ≤20 wt% clay minerals, free of fibres and quartz, can be used as feed additive for all animal species. The zeolitic rocks of Thrace on average contain, 23-89 wt% HEUtype zeolite (clinoptilolite-heulandite), 8-45 wt% mordenite (ten locations), 24 wt% analcime (one location), 1-11 wt% mica, 1 11 wt% clay minerals, 3-37 wt% quartz, 2-29 wt% cristobalite, 3-34 wt% feldspars and 0-22 wt% amorphous materials. Only one location contains 89 wt% HEU-type zeolite (clinoptilolite-heulandite), 2 wt% clay minerals, is free of fibres, but unfortunately it contains 3 wt% quartz and 2 wt% cristobalite. Considering the mineralogical composition, the zeolitic rocks of Thrace do not meet the requirements of the EU Regulation No 651/2013, and thus cannot be used as feed additives for all animal species and consequently as nutrition supplements, since the zeolitic rocks in all locations, contain on average 3-37 wt% quartz, 2-29 wt% cristobalite, 8-45 wt% mordenite (fibrous zeolite) in 10 locations, 24-65 wt% zeolites (HEU-type ± mordenite ± analcime) in 28 locations, 74 wt% HEUtype zeolite in 2 locations and 77 wt% HEU-type zeolite in 1 location.
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Ramírez, Adriana Medina, Prócoro Gamero Melo, and José Manuel Almanza Robles. "Synthesis of Nanoporous Materials and their Functionalization for Environmental Applications." Materials Science Forum 783-786 (May 2014): 2005–10. http://dx.doi.org/10.4028/www.scientific.net/msf.783-786.2005.
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In this work, W, P and faujasite zeolites were synthesized using fly ash as raw material, a waste material derived of coal fired plants in Mexico. Two different synthesis methods were used. Zeolites were submitted a functionalization treatment exchanging their metallic ions by ammonium, aluminum and ferrous ions. Chemical, structural and textural properties of functionalized zeolites were evaluated. As (V) and As (III) adsorption capacity of modified zeolites were assessed. Changes on their structural properties were no significant. While the textural properties such as pore volume, specific surface area and pore size distribution were dependent of nature of ion exchanged, and the accessibility of extra-framework sites of the zeolites. Functionalization with di and trivalent ions allow changing the zeolitic surface charge. This modification led to increase their ability to adsorb anionic species from aqueous solutions. The results shown that, the adsorption capacity was dependent of zeolite type and their chemical surface nature. W zeolite modified with aluminum ions achieved the highest arsenic (V) adsorption capacity. While ferrous functionalization on W zeolite shown a high affinity to remove As (III) species from aqueous solutions.
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Qaid, Ali M. "Integration of Geological, Geochemical, Mineralogical and Remote Sensing Data for Studying Zeolite Deposits of Al-Ahyuq-Taiz, Yemen." International Journal for Research in Applied Science and Engineering Technology 9, no. 9 (September 30, 2021): 1827–41. http://dx.doi.org/10.22214/ijraset.2021.37959.
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Abstract: Zeolite deposits crop out at Al-Ahyuq area, and lies at about 89 km southwest of Taiz city. It is one of the most important zeolite localities in Yemen. The study area is covered by the Yemen volcanic group. X-Ray Diffraction (XRD) analyses showed that clinoptilolite is the major type of Al-Ahyuq zeolites with high purity. Chemical analysis shows that the studied zeolitic tuff samples have silica content ranging from 63.10 wt% - 71.1wt% with an average 68.69 wt%, Fe2O3 [as total iron] with an average 2.38wt%, MgO with an average 0.44 wt% and TiO2 with an average 0.17wt%. These chemical properties of Al-Ahyuq zeolite deposits are with low impurities content such as CaO and MgO, compared to those deposits found in other countries around the world. The chemical and mineralogical studies support that the zeolite minerals of the Al-Ahyuq area formed by subaerial hydrothermal alteration of the parent volcanic glass. The ASTER bands as false colour composite (1-R, 2-G, 3-B), and band ratios 3/9 and 4/6 highlighted area of zeolite deposits dominated as bright pixels. The band ratio combination 4/6-R, 2/1-G and 3/2-B is effective in mapping of Al-Ahyuq zeolitic tuffs. Spectra after being resampled to ASTER VNIR+SWIR bands of the study area comparing with the USGS library spectra of zeolite – clinoptilolite shows almost identical and confirmed that clinoptilolite is the major of zeolite deposits in Al-Ahyuq area. Chemical and mineralogical investigation of the Al-Ahyuq zeolite (clinoptilolite) deposits recommends many important agricultural, environmental, and industrial applications. Keyword: Zeolitic tuff; clinoptilolite; XDR; XRFS; ASTER data; band ratio
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Kasic, Vladan, Slavica Mihajlovic, Dragana Zivotic, Vladimir Simic, Jovica Stojanovic, Zivko Sekulic, and Milan Kragovic. "Characterization of the zeolitic tuff from the “Igros-Vidojevici” deposit regarding geological and technological aspects." Chemical Industry 72, no. 1 (2018): 29–37. http://dx.doi.org/10.2298/hemind170428015k.
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This study presents investigations of zeolitic tuff samples from the ?Igros- -Vidojevici? deposit. The aim of the research was to determine the quality of samples taken from all deposit parts. Thus, samples were taken from the footwall (?Zeolit 1?), and four samples from the central deposit part (?Zeolit 2?, ?Zeolit 3?, ?Zeolit 4? and ?Zeolit 5?). Characterization of the samples included chemical analysis, determination of the adsorption coefficient for methylene blue dye and cation-exchange capacity (CEC), X-ray powder diffraction analysis (XRPD), differential thermal and thermogravimetric analysis (DTA and TGA), and Fourier transform Infrared spectroscopic analysis (FTIR). Results have shown that the footwall consists mostly of clays, whereas zeolite minerals dominate in the rest of the deposit. XRD analysis of the ?Zeolit 1? sample confirmed presence of smectite and kaolinite clays, while zeolite of analcime type and quartz are present as smaller fractions. Chemical composition analysis and determination of heavy metal contents showed a significant amount (7.58%) of Fe2O3 in this sample. Therefore, further research can be pursued to find a method for removal of magnetic impurities in this deposit portion in order to utilize the clay fraction. On the other hand, according to XRD, FTIR, DTA/TGA and SEM/EDS analyses, samples which belong to the central deposit part (?Zeolit 2?5?) consist of clinoptilolite zeolite type, while clays are present in less than 10%. Thus, clays (smectites and kaolinite) accompanied with analcime and quartz are the most abundant footwall minerals while central deposit parts contain predominantly clinoptilolite accompanied with small amounts of clays. Mineragenetically, zeolites are most abundant in the ?Zeolit 2? and ?Zeolit 3? samples. The smallest value of CEC was determined for the ?Zeolit 1? sample (46.98 mmol/100g). According to CEC values determined for ?Zeolit 2? and ?Zeolit 3? (141.99 and 121.01 mmol/100 g, respectively) these samples are of the best quality, and could be utilized as adsorbents of inorganic pollutants from contaminated waters. Moreover, they could be potentially used for removal of mycotoxins from cattle feed. ?Zeolit 4? and ?Zeolit 5? samples have shown slightly lower CEC values (89.48 and 83.75 mmol/100 g, respectively), which implies lower quality, and, therefore, could be used for soil quality improvement. Finally, determination of the external CEC has revealed a significant difference between ?Zeolit 1? and ?Zeolit 5? samples (17.9 and 5.31 mmol/100 g, respectively).
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Bux, Nabi, Sadam Hussain Tumrani, Razium Ali Soomro, and XiaodongJi. "Synthesis of Zeolites from Coal Fly Ash and Their Environmental Application." International Journal of Economic and Environmental Geology 13, no. 2 (June 14, 2022): 58–61. http://dx.doi.org/10.46660/ijeeg.v13i2.32.
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This study aims to make adsorption-capable zeolite from coal fly ash, a waste product from coal-fired power plants (CFA). When it comes to commercializing sorbent, the total cost and efficiency of the adsorbent material are critical. This work used tap water instead of distilled water (DW) to synthesis zeolite from fly ashes at 90°C crystallization temperatures. The discovery lays the door for a cost-effective but easy technique of synthesizing viable zeolitic materials for adsorption applications using waste products like coal fly ash. According to the comprehensive characterization, the support for the use of TP to make zeolites is based on its larger particle size, and lower carbon impurities. The generated zeolite was homogenous and A-type, and applied as an adsorbent to remove traces of heavy metals contaminants. During a 25-minute agitation period, the zeolites produced with TP had a greater adsorption capacity. In principle, the proposed approach permits the synthesis of low-cost, high-efficiency zeolite-based adsorbent materials for environmental remediation without the use of harmful or expensive chemicals.
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Vasconcelos, Arthur Abinader, Thomas Len, Alex de Nazaré de Oliveira, Ana Alice Farias da Costa, Allan Rodrigo da Silva Souza, Carlos Emmerson Ferreira da Costa, Rafael Luque, Geraldo Narciso da Rocha Filho, Renata Coelho Rodrigues Noronha, and Luís Adriano Santos do Nascimento. "Zeolites: A Theoretical and Practical Approach with Uses in (Bio)Chemical Processes." Applied Sciences 13, no. 3 (February 1, 2023): 1897. http://dx.doi.org/10.3390/app13031897.
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This review provides a state-of-the-art summary of distributed zeolite technology, as well as identifying strategies to further promote the absorption of these materials in various areas of study. Zeolites are materials that can be synthesized or found in natural rock deposits a with a basic composition consisting in Al, Si, and O. Zeolite’s consideration as a future material is due to many facile synthesis methods to obtain different structures with variations in pore size, surface area, pore volume and physical properties. These methods are developed using the control of relevant synthesis parameters that influences structure formation, such as crystallization temperature, time of aging and/or crystallization, stoichiometric relationships between components of synthesis gel, pH of the medium, and in some cases the type of structure-directing agent. Each method will lead to geometric changes in the framework formation, making possible the formation of typical chemical bonds that are the fingerprint of any zeolitic structure (O-Si-O and Al-O-Si), forming typical acid sites that give specificity in zeolite and allows it to act as a nanoreactor. The specificity is a characteristic that in some cases depends on selectivity, a fundamental property derived of the porosity, mostly in processes that occur inside the zeolite. In processes outside the structure, the surface area is the main factor influencing this property. Moreover, there are many natural sources with adequate chemical composition to be used as precursors. Some of these sources are waste, minimizing the deposition of potential hazardous materials that can be recalcitrant pollutants depending on the environment. Besides its uses as a catalyst, zeolite serves as a support for many bioprocesses; therefore, this review aims to explain relevant aspects in chemical nature, physical properties, main methods of synthesis, main precursors used for synthesis, and relevant applications of zeolites in chemical catalysis and biological processes.
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Septiani, Upita, Fiska Julian Tasari, and Zilfa Zilfa. "Adsorpsi Asam Humat pada Zeolit Alam yang Dimodifikasi dengan TiO2." Jurnal Riset Kimia 11, no. 1 (March 30, 2020): 43–51. http://dx.doi.org/10.25077/jrk.v11i1.344.
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This research modified natural zeolite with TiO2 synthesized by the sol-gel process which was applied as a humic acid adsorbent. The purpose of this study was to coat natural zeolites with TiO2 to increase the adsorption capacity of natural zeolites as humic acid adsorbents. The natural zeolite powders were obtained from Kabupaten Solok, West Sumatra, based on X-ray Fluorescence (XRF) analysis, the ratio of silica/alumina (Si/Al) was 4.35, indicating that natural zeolite was clinoptilolite zeolite. Scanning Electron Microscopy (SEM) analysis showed natural zeolite has a rough surface with closed pores while zeolite coated with TiO2 (zeolite/TiO2) has a homogeneous, smooth surface with open pore. The results of the Energy Dispersive X-Ray Spectroscopy (EDS) analysis showed that the level of TiO2 was 7.1%, this result showed that TiO2 has been coated on the surface of the zeolite. Natural zeolite and zeolite/TiO2 were applied as humic acid adsorbents. Maximum adsorption capacity of natural zeolites and zeolites/TiO2 were 0.2787 mg/g and 1.199 mg/g, respectively.
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Gackowski, Mariusz, Jerzy Podobiński, Ewa Broclawik, and Jerzy Datka. "IR and NMR Studies of the Status of Al and Acid Sites in Desilicated Zeolite Y." Molecules 25, no. 1 (December 20, 2019): 31. http://dx.doi.org/10.3390/molecules25010031.
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The desilication of zeolite Y (of Si/Al = 31) that was previously dealuminated by steaming and acid treatment was studied. Desilication of zeolites of high Si/Al module in alkali solutions extracts both Si and Al from zeolite crystals, but while Si remains in solution, Al is reinserted into the zeolite grain. The main goal of our study was to follow the status of Al reinserted into zeolite during the desilication procedure, and its role in the formation of acid sites of the Brønsted and Lewis types. The properties of Al were followed by 27Al MAS NMR spectroscopy (for parent samples and zeolites treated either with NaOH or NaOH/tetrabutylammonium hydroxide), whereas the acid sites generated in the final stages were studied by IR spectroscopy with NH3 and CO as probe molecules. In non-desilicated zeolite, most of the Al was in a typically zeolitic tetrahedral coordination, while both NMR and quantitative IR studies of NH3 sorption evidenced that Al that was extracted by desilication and was subsequently reinserted had a tetrahedral coordination similar to amorphous aluminosilicates and showed an ion exchange ability. After the exchange of Na+ to NH4+ and decomposition of NH4+ ions, reinserted Al forms generated protonic sites from which some condensed at higher temperatures producing Lewis acid sites (with stoichiometry typical for zeolites i.e., the condensation of two protonic sites produces one Lewis site) but some other kept their character.
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Zhang, Hai Rong, Hong Yan Liu, Yu Jiang, Xun Tao, Xiao Hua Chang, Wen Shan Zhang, Bo Wang, Jian Hong Liu, and Yong Guo. "Morphology-Controlled Synthesis of ZSM-5/MCM-41 Composite Zeolite." Applied Mechanics and Materials 599-601 (August 2014): 77–80. http://dx.doi.org/10.4028/www.scientific.net/amm.599-601.77.
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ZSM-5/MCM-41 composite zeolites were synthesized by a two-step hydrothermal crystallization procedure using binary templates of cetyltrimethylammonium bromide (CTAB) and tetrapropylammonium hydroxide (TPAOH). The effects of aluminum content on zeolite particle morphology and structure were studied. Powder X-ray diffraction (XRD) results showed that the composite zeolites are of both MCM-41 structure and zeolitic MFI structure. SEM results showed that the morphology of composite zeolites is significantly influenced by the aluminum content.
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Septiansyah, Sy Indra, and Maya Santi. "Pemanfaatan Alumina Waste dari Tailing Bauksit Menjadi Zeolit Adsorben." EKSPLORIUM 39, no. 2 (January 31, 2019): 123. http://dx.doi.org/10.17146/eksplorium.2018.39.2.4982.
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ABSTRAK Alumina waste dari tailing bauksit merupakan produk samping yang berasal dari hasil benefisiasi bijih bauksit. Proses benefisiasi dilakukan dengan cara memisahkan partikel-partikel yang ada seperti lumpur atau clay, akar-akar, butiran bijih bauksit berkisar 2 mm yang dibuang atau menjadi waste product atau disebut sebagai limbah tailing. Tingginya kadar alumina dan silika dalam tailing bauksit menjadi salah satu alasan mengapa tailingini dapat dimanfaatkan sebagai bahan dasar dalam pembuatan produk baru yaitu zeolit sintetis. Zeolit sintetis dipilih karena zeolit merupakan produk impor, harganya mahal dan memiliki sifat yang seragam serta >150 jenis zeolit sintetis dapat dibuat secara komersial dan bahkan di industri zeolit dapat dimanfaatkan secara luas sebagai adsorben, penukar ion, membrane, katalis, dan lain-lain.Hasil analisis kimia tailing bauksit menunjukkan komposisi: alumina (Al2O3) sekitar 49,41%, silika (SiO2) sekitar 12,58%, hematit (Fe2O3) sekitar 10,6% dan beberapa oksida anorganik lainnya dalam jumlah yang kecil. Proses konversi tailing bauksit menjadi zeolit adsorben dilakukan dengan metode fusi kaustik untuk mendapatkan ekstrak fusi (mother liquor) kemudian dilanjutkan dengan penambahan prekursor natrium silikat dengan formula sintesis Si/Al(1:1). Kristalisasi produk dilakukan dengan menggunakan metode hidrotermal pada suhu rendah dengan variable waktu inkubasi yang ditentukan. Reaksi sodium aluminat dan sodium silikat telah mentransformasi fasa amorf gel menjadi fasa kristalin zeolit yang berbentuk serbuk putih halus.ABSTRACTA lumina waste from bauxite tailings is the by products derived from bauxite ore beneficiation. The beneficiation process is done by separating the particles that exist such as mud or clay, roots, grain, bauxite ore ranges from 2 mm are discarded or be referred to as a waste product or tailings. High concentration of alumina and silica in bauxite tailings considered as one of the reasons why these tailings can be used as base material in the making new products, namely synthetic zeolites. Zeolites synthetic is selected because zeolites are imported, expensive and have uniform properties and >150 types of synthetic zeolites can be made commercially and even in industrial zeolite can be used widely as an adsorbent, ion exchange, membranes, catalysts, etc. The chemical analysis of bauxite tailings showed the composition of alumina (Al2O3) is approximately 49.41% silica (SiO2) is about 12.58%, hematite (Fe2O3) is approximately 10.6% and some other inorganic oxides are small amounts. The conversion process bauxite tailings into zeolite is carried out by caustic fusion method to extract the fusion (alumina precursor) followed by the addition of sodium silicate precursor with synthesis formula 1.2Na2O.0.5SiO2.0.5Al2O3.10H2O and crystallization products is carried out by the hydrothermal method at low temperatures with variable incubation period specified. The results showed that the zeolite synthesis of bauxite tailings using caustic fusion and followed by crystallization at low temperature and under atmospheric pressure has succeeded in transforming the product into an amorphous phase to the crystalline phase product zeolite adsorbent.
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Asgar Pour, Zahra, Yasser A. Alassmy, and Khaled O. Sebakhy. "A Survey on Zeolite Synthesis and the Crystallization Process: Mechanism of Nucleation and Growth Steps." Crystals 13, no. 6 (June 15, 2023): 959. http://dx.doi.org/10.3390/cryst13060959.
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Zeolites, as a class of crystalline minerals, find a wide range of applications in various fields, such as catalysis, separation, and adsorption. More recently, these materials have also been developed for advanced applications, such as gas storage, medical applications, magnetic adsorption, and zeolitic-polymeric membranes. To effectively design zeolites for such intriguing applications, it is crucial to intelligently adjust their crystal size, morphology, and defect population in relation to crystal perfection. Optimizing these fundamental parameters necessitates a deep understanding of zeolite formation mechanisms, encompassing the thermodynamics and kinetics of nucleation steps as well as crystallite growth. In this review, we discuss the formation of zeolites from this perspective, drawing on recent studies that highlight new achievements in remodeling and modifying zeolite synthesis routes. The ultimate aim is to provide better comprehension and optimize the functionality of zeolites for the aforementioned applications.
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Pham, Thi Mai Hương, Hong Con Tran, and Thi Phuong Quynh Le. "Synthesis of zeolites from Tay Nguyen red mud and test of their adsorption ability." Journal of Vietnamese Environment 9, no. 1 (June 28, 2018): 32–37. http://dx.doi.org/10.13141/jve.vol9.no1.pp32-37.
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Red mud is the waste from alumina production, contain high amount of residualalkaline,aluminateand some metals oxide such as iron oxide, siliconoxide, titanium oxide...; in which aluminum and silica proportions could be usedfor zeolite synthesis. The zeolite was synthesized by the hydrothermal method for obtaining RM-ZeO-Si which was signed for Si added and RM-ZeO- SiAl for both Si and Al added. The obtained zeolites were then characterized by the XRD, EDX, SEM, BET and FT-IR methods. The results indicate that the synthesized zeolite is likely the new kind one with one sulfur atom in the crystaline unit and has general formula of Na8(Al6Si6O24)S.4H2O. We tested the ability of ammonium and nitrite adsorption of the synthesized zeolites and found that the synthesized zeolites had very higha dsorption capacity of both cation ammonium and anionnitrite but the adsorption mechanism of each was different. Adsorption mechanism of ammonium was suggested as predominant ion exchange between ammonium cation in solution and sodium cation in zeolite crystals while nitrite adsorbed on surface material by electrostatic attractive force between nitrite anion and electropositive surface of iron oxide particles.
Bùn đỏ là chất thải từ quá trình sản xuất nhôm, chứa lượng lớn kiểm, oxit nhôm và một số oxit khác như sắt oxit, silic oxit, titan oxit…trong đó tỷ lệ nhôm và silic có thể sử dụng để tổng hợp zeolit. Vật liệu zeolit được tổng hợp bằng phương pháp thủy nhiệt, thêm Si được ký hiệu là RM-ZeO-Si; vật liệu thêm đồng thời Si, Al được ký hiệu là RM- ZeO-Si/Al. Vật liệu zeolit tổng hợp được phân tích đặc trưng cấu trúc bằng các phương pháp XRD, EDX, SEM, BET và FT-IR. Các kết quả phân tích cho thấy vật liệu zeolit tổng hợp có điểm mới khác biệt so với các zeolit thông thường bởi trong cấu trúc phân tử có chứa nguyên tử S, công thức phân tử của zeolit là Na8(Al6Si6O24)S.4H2O. Kết quả khảo sát hấp phụ ban đầu cho thấy vật liệu có khả năng hấp phụ với cả ion amoni và nitrit, cơ chế hấp phụ khác nhau. Quá trình hấp phụ cation amoni là do quá trình trao đổi ion giữa cation amoni với cation natri trong tinh thể zeolit, còn quá trình hấp phụ nitrit trên bề mặt vật liệu do tương tác tĩnh điện giữa nitrit với các cấu tử oxit sắt.
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Korde, Akshay, Byunghyun Min, Elina Kapaca, Omar Knio, Iman Nezam, Ziyuan Wang, Johannes Leisen, et al. "Single-walled zeolitic nanotubes." Science 375, no. 6576 (January 7, 2022): 62–66. http://dx.doi.org/10.1126/science.abg3793.
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Zeolitic nanotubes Nanotubes generally have solid walls, but a low-dimensional version of zeolites now introduces porosity into such structures. Korde et al . used a structure-directing agent with a hydrophobic biphenyl group center connecting two long alkyl chains bearing hydrophilic bulky quaternary ammonium head groups to direct hydrothermal synthesis with silicon-rich precursors (see the Perspective by Fan and Dong). The nanotubes have a mesoporous central channel of approximately 3 nanometers and zeolitic walls with micropores less than 0.6 nanometers. Electron microscopy and modeling showed that the outer surface is a projection of a large-pore zeolite and the inner surface is a projection of a medium-pore zeolite. —PDS
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Filippidis, A., N. Kantiranis, M. Stamatakis, A. Drakoulis, and E. Tzamos. "THE CATION EXCHANGE CAPACITY OF THE GREEK ZEOLITIC ROCKS." Bulletin of the Geological Society of Greece 40, no. 2 (January 1, 2007): 723. http://dx.doi.org/10.12681/bgsg.16680.
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Forty two zeolitic rock samples, from the Prefectures ofEvros, Rhodope, Samos and Cyclades, have been investigated for their cation exchange capacity (CEC, in meq/100g) and the mineralogical composition (wt.%), using the Ammonium Acetate Saturation method and Powder X-ray Diffraction method, respectively. HEU-type zeolite (heulandite-clinoptilolite) was found in Ρ etrota area (43-89 wt.%, CEC 101- 217), Samos island (34-91 wt.%, CEC 93-217), Pentalofos area (68-74 wt.%, CEC 124-202), Metaxades area (47-64 wt.%, CEC 119-140) and Thira island (33 wt.%, CEC 118). Mordenite was found in Samos island (64 wt.%, CEC 150), Polyegos island (61 wt.%, CEC 136), Thira island (56 wt.%, CEC 130), Milos island (45 wt.%, CEC 97), Kimolos island (30 wt.%, CEC 96) and Feres area (5 wt.%, CEC 22). Analcime was found in Samos island (27-71 wt.%, CEC 104-285) and Darmeni area (16 wt.%, CEC 62). Chabazite was found in Samos island (66 wt.%, CEC 243). HEU-type zeolite+mordenite were found in Feres area (45-74 wt.%, CEC 132-209), Samos island (81 wt.%, CEC 184), Thira island (72 wt.%, CEC 177), Polyegos island (66 wt.%, CEC 153) and Skaloma area (51-60 wt.%, CEC 126-143). HEUtype zeolite+phillipsite were found in Samos island (47 wt.%, CEC 170) and HEUtype zeolite+analcime were found in Samos island (55 wt.%, CEC 129). The CEC of the zeolitic rocks show positive correlations with the type of zeolite and the microporous minerals (zeolites+micas+clay minerals) content, mainly affected by the zeolites and to lesser extent by micas and clay minerals.
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Nuryoto, Nuryoto, Teguh Kurniawan, and Indar Kustiningsih. "Pengujian Zeolit Alam Mordenit Sebagai Penjerap Proses Pendegradasian Kandungan Amonium di dalam Air Tambak." Jurnal Teknologi Lingkungan 21, no. 1 (January 30, 2020): 49–55. http://dx.doi.org/10.29122/jtl.v21i1.3745.
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ABSTRACTIndonesia has an abundant quantity of natural zeolites that have not yet been utilized maximally. On the other hand, fishpond farmers have a problem regarding the presence of ammonium in the fishpond water which will negatively impact to survival of fish, especially small fish. To solve this problem, this research was utilizing natural zeolite to degrade ammonium in the fishpond water. This research aimed to test mordenite natural zeolite from Bayah as an adsorbent to collaborate some variables impact to reach more maximal adsorption. The variables that were used to be observed were: mordenite natural zeolite from Bayah as an adsorbent which has been activated by 1-7 N H2SO4 and the other was without activation, ammonium concentration of 80-800 ppm, the particle size of adsorbent of 80 and 150 mesh, stirring speed of 600 and 800 rpm, and without stirring by duration adsorption time of 60 minutes. The research results showed that mordenite natural zeolite after activated was able to adsorb of 100% ammonium, while for the mordenite natural zeolite from Bayah without stirring was of 80%, by the same absorption time. These results will give significant benefits for fishpond farmers to increase their productivity because of the increase in fish survival.Keywords: adsorption, adsorbent, zeolite, amoniumABSTRAKKandungan zeolit alam di Indonesia cukup melimpah dan belum termanfaatkan secara maksimal. Pada sisi lain petani tambak dihadapkan pada masalah terdapatnya kandungan amonium di dalam air tambak, yang akan berdampak negatif bagi keberlangsungan hidup ikan, terutama ikan yang masih kecil. Penelitian ini mencoba memanfaatkan zeolit alam guna mendegradasi kandungan amonium dalam air tambak. Tujuan penelitian ini adalah melakukan pengujian terhadap zeolit alam mordenit dari Bayah sebagai adsorben, baik dilakukan dengan pengadukan maupun tanpa pengadukan, serta mengkolaborasi beberapa variabel yang berpengaruh agar hasil adsorpsi lebih maksimal. Observasi dilakukan dengan zeolit alam mordenit dari Bayah yang telah diaktivasi dengan 1-7 N H2SO4 maupun tanpa aktivasi, rentang konsentrasi larutan amonium 80-800 ppm, ukuran partikel adsorben 80 dan 150 mesh, kecepatan pengadukan 600 dan 800 rpm, dan tanpa pengadukan serta lamanya waktu penyerapan 60 menit. Hasil penelitian menunjukan hasil yang sangat baik, dan secara umum zeolit alam mordenit Bayah teraktivasi telah mampu melakukan adsorpsi amonium sebesar 100%, sedangkan untuk zeolit alam mordenit Bayah tanpa pengadukan sebesar 80% pada waktu adsorpsi yang sama.Kata kunci: adsorpsi, adsorben, zeolit, amonium
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Flores Díaz, Alicia Amairani, Martha Alicia Velázquez Machuca, Adriana Medina Ramírez, José Luis Montañez Soto, José Venegas González, and José Luis Pimentel Equihua. "Boron adsorption on modified zeolites: Effect of modifier and source of water." Revista Internacional de Contaminación Ambiental 39 (June 2, 2023): 139–57. http://dx.doi.org/10.20937/rica.54473.
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The removal of boron from drinking water is a concern in various parts of the world due to the toxic effects of this metalloid in high concentrations. In this paper, zeolites LTL and FAU X were synthesized and modified with salts of nickel (NiCl2), iron (FeCl3), and aminopropyltriethoxysilane (APS) in order to promote their affinity for boron species present in aqueous systems. The adsorption capacity of modified zeolites for boron was evaluated in a synthetic boron solution and with groundwater samples for human use. The effect of the pH and zeolite dose was studied in adsorption tests using groundwater. The modified zeolites were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, nitrogen physisorption, and Fourier-transform infrared spectroscopy. Results indicated that the modification of zeolites favors affinity for boron species. The highest adsorption capacity of boron on zeolites was achieved in the synthetic solution. The adsorption capacity of the modified zeolites depended on the pH, the electrical conductivity, the modifying agent, the zeolitic structure, and the dose of adsorbent. The zeolitic structure-modifying agent interaction was decisive for boron adsorption capacity, with LTL-Ni zeolite being the best-performing adsorbent, thanks to its textural properties and nickel’s ability to form complexes with boron species.
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Wu, Di, Yi Huang, Guqing Xiao, Xuan Li, Xia Yao, Zixuan Deng, and Rui Tan. "In situ synthesis of zeolites by geopolymerization with NaOH/KOH mixed solution and their potential application for Cd(II) immobilization in paddy soil." Clay Minerals 56, no. 2 (June 2021): 156–67. http://dx.doi.org/10.1180/clm.2021.29.
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AbstractGeopolymers can be transformed into zeolites under certain synthesis conditions. However, zeolite formation is not frequently reported in KOH-activated geopolymers. This study attempted to explore zeolite synthesis through geopolymerization for a curing time of 24 h using mixed NaOH/KOH alkaline solution as an activator, and then applying the geopolymer-supported zeolites to immobilize Cd(II) in paddy soil. The K2O/M2O–H2O/SiO2 and K2O/M2O–OH–/SiO2 binary zeolite crystallization phase diagrams were obtained. Zeolite A, faujasite and sodalite formed at lower K2O/M2O molar ratios (0–0.2), ferrierite formation was favoured at a K2O/M2O molar ratio of 0.2–0.4 and zeolite K-I and zeolite F-K (both K-zeolites) were observed at a K2O/M2O molar ratio of 0.6. The geopolymer-supported zeolites had micropores and mesopores and specific surface area values of 44.2–74.8 m2 g–1. The material displayed a considerable Cd(II) immobilization efficiency (55.6–58.7% at 4–6 wt.% addition of zeolite).
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Kurniawan, Teguh, Dhimas Satria, Juniafit Bima Saputra, Muhammad Roil Bilad, Nik Abdul Hadi Md Nordin, and Hairus Abdullah. "Conversion of Green Silica from Corn Leaf into Zeolites Na A-X." Indonesian Journal of Science and Technology 7, no. 2 (May 9, 2022): 171–86. http://dx.doi.org/10.17509/ijost.v7i2.45831.
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Combustion of corn leaf as a model of biomass from agricultural waste is a simple way to obtain the energy. It produces a low-value by-product of ash and is rich in silica that can become a precursor for zeolite production. In this study, acid-treated corn leaves combustion was performed to produce high purity silica (SiO2). The diffraction pattern suggested that the extracted silica was amorphous without the impurities phase. Additionally, the nitrogen isotherm indicated that the material was highly mesoporous silica with a total surface area of 200 m2/g. The hydrothermal method was then applied with a composition molar ratio of 1.25SiO2:1Al2O3:5Na2O:250H2O to synthesize zeolites from the silica. The temperature and time effect on the hydrothermal zeolite’s synthesis was investigated. The diffraction pattern shows that high crystalline zeolite Na A-X was produced at temperatures of 100°C and 8 h hydrothermal time. According to nitrogen physisorption analysis, the zeolite Na A-X consisted of micropores with a total surface area of 270 m2/g. The morphology of zeolite Na A-X was cube for the Na-A and octahedral for the Na-X. The hydrothermal temperature and time highly affected the zeolite formed. This research suggested that the ash waste could be valorized through conversion into a high economic value zeolites.
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Marosz, Monika, Bogdan Samojeden, Andrzej Kowalczyk, Małgorzata Rutkowska, Monika Motak, Urbano Díaz, Antonio E. Palomares, and Lucjan Chmielarz. "MCM-22, MCM-36, and ITQ-2 Zeolites with Different Si/Al Molar Ratios as Effective Catalysts of Methanol and Ethanol Dehydration." Materials 13, no. 10 (May 22, 2020): 2399. http://dx.doi.org/10.3390/ma13102399.
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MCM-22, MCM-36, and ITQ-2 zeolites with the intended Si/Al molar ratios of 15, 25, and 50 were synthetized and tested as catalysts for dehydration of methanol to dimethyl ether and dehydration of ethanol to diethyl ether and ethylene. The surface concentration of acid sites was regulated by the synthesis of zeolite precursors with different aluminum content in the zeolite framework, while the influence of porous structure on the overall efficiency of alcohol conversion was analyzed by application of zeolitic materials with different types of porosity—microporous MCM-22 as well as microporous-mesoporous MCM-36 and ITQ-2. The zeolitic samples were characterized with respect to their: chemical composition (ICP-OES), structure (XRD, FT-IR), texture (N2 sorption), and surface acidity (NH3-TPD). Comparison of the catalytic activity of the studied zeolitic catalysts with other reported catalytic systems, including zeolites with the similar Si/Al ratio as well as γ-Al2O3 (one of the commercial catalysts for methanol dehydration), shows a great potential of MCM-22, MCM-36, and ITQ-2 in the reactions of alcohols dehydration.
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Rahayu, Endang Sri, Desi Bentang, and Ghina Fauziyyah. "Penggunaan Kembali Limbah Cair dari Sintesis Zeolit Y sebagai Sumber Silika untuk Sintesis Zeolit Y secara Hidrotermal." Jurnal Teknik Kimia Indonesia 18, no. 2 (February 25, 2020): 53. http://dx.doi.org/10.5614/jtki.2019.18.2.4.
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Abstrak. Penelitian ini dilakukan untuk mempelajari kemungkinan limbah cair atau mother liquor dari sintesis zeolit Y yang masih mengandung silika dapat digunakan kembali sebagai sumber silika untuk sintesis zeolit Y, dengan menambahkan bibit kristal dan alumina ke dalam limbah cair. Sintesis zeolite Y dilakukan secara hidrotermal pada temperatur 93oC dan pH sekitar 13. Rasio molar silika /alumina sekitar 10 mol/mol di dalam starting material diperlukan untuk mendukung terbentuknya zeolit Y. Seberapa banyak turunan atau penggunaan kembali limbah cair sintesis zeolit Y untuk sintesis zeolit Y, dikaji dalam penelitian ini. Hasil sintesis zeolit Y diuji nilai rasio molar SiO2/Al2O3 dengan alat X-Ray Diffractometer (XRD), dan morfologinya dengan alat Scanning Electron Microscopy (SEM). Hasil sintesis zeolite Y menunjukkan hanya mother liquor turunan ke-1 saja yang layak digunakan kembali untuk sintesis zeolite Y karena zeolite P terbentuk secara signifikan ketika digunakan mother liquor turunan ke-2. Penelitian ini juga mengamati bahwa pembentukan zeolite P terjadi ketika konsentrasi SiO2 dalam starting material adalah rendah. Konsentrasi SiO2 yang rendah pada mother liquor turunan ke-1 juga diduga berkontribusi terhadap penurunan rasio SiO2/Al2O3 pada zeolit Y hasil sintesis, yaitu 2.63 mol/mol, dari 3.74 mol/mol ketika menggunakan parent starting material. Peningkatan rasio SiO2/Al2O3 zeolit Y hasil sintesis dapat diupayakan, yang tampak lebih baik dilakukan melalui penaikan jumlah bibit kristal dari pada melalui penaikan waktu reaksi, untuk memperkecil terbentuknya zeolite P. Kata kunci: limbah cair, sumber silika, sintesis, hidrotermal, zeolit Y. Abstract. Reuse of Liquid Waste from Zeolite Y Synthesis as a Silica Source for Hydrothermal Synthesis of Y Zeolite. The objective of this study was to study the possibility of mother liquor of synthesis of zeolite Y which still contains high silica, can be reused as a source of silica for synthesis of zeolite Y, by adding seeds and alumina. The synthesis of zeolite Y was done hydrothermally at temperature of 93oC and at a pH of about 13. The mole ratio of silica / alumina in the starting material at about of 10 mol / mol were needed to achieve an adequate process. How many derivatives or repetitions of the mother liquor can be reused for synthesis of zeolite Y, it will be examined in this study. The result of the synthesized zeolite Y was then characterized of the SiO2 / Al2O3 molar ratio by X-Ray Diffraction (XRD) and the morphology by Scanning Electron Microscopy (SEM). The Results of the synthesis of zeolite Y shows that the only 1st mother liquor appropriate to be reused for synthesis of zeolite Y. The reduction of the SiO2 /Al2O3 molar ratio of synthesized Y zeolite from the 3.74 mol / mol when using parent starting material become 2.63 mol / mol when using mother liquor was observed The formation of zeolite P was also obtained when synthesis zeolite Y using mother liquor with a low concentration of SiO2. The SiO2Al2O3 molar ratio of the synthesized zeolite Y can be raised by inceasing the quantity of seeds in the starting material rather than by increasing reaction time, to minimize the formation of zeolite P. Keywords: mother liquor, silica source, synthesis, hydrothermal, zeolite Y. Graphical Abstract
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Dang, Long Van, Thu Thi Minh Nguyen, Dang Van Do, Son Thanh Le, Trong Dinh Pham, and Anh Thi Mai Le. "Study on the Synthesis of Chabazite Zeolites via Interzeolite Conversion of Faujasites." Journal of Analytical Methods in Chemistry 2021 (March 29, 2021): 1–10. http://dx.doi.org/10.1155/2021/5554568.
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The interzeolite conversion of faujasite (FAU-type) zeolites to chabazite (CHA-type) zeolite in the presence of N,N,N-trimethyladamantammonium and N,N,N-dimethylethylcyclohexylammonium cations was investigated over a large compositional range by carefully controlling the reaction mixture compositions. Highly crystalline CHA zeolites were also obtained by the transformation of several zeolite types including EMT, LTL, LEV, RTH, and MFI frameworks. The formation of CHA zeolite from FAU zeolite precursors was substantially faster than that from zeolite L with a similar composition. High-silica CHA zeolites were also produced successfully using a mixture of TMAda with a number of less expensive organic structure-directing agents. The CHA zeolite materials have been synthesized with high crystallinity and with a Si/Al ratio ranging from 5 to 140. Our data support the importance of structural similarity between the zeolite precursors, nucleation/crystallization processes, and the zeolite product in the interzeolite conversion compared to conventional amorphous aluminosilicate gels. Our synthetic methods could be used to prepare other 8-membered ring zeolites such as AEI and AFX frameworks, potential candidates for selective catalytic reduction of NOx, light olefin production, and CO2 abatement.
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Netzsch, Philip, Romy Ettlinger, and Russell E. Morris. "Controllable surfactant-directed zeolitic-imidazolate-8 growth on swollen 2D zeolites." APL Materials 11, no. 3 (March 1, 2023): 031115. http://dx.doi.org/10.1063/5.0139673.
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To meet society’s need for more and more specialized materials, this work focuses on the preparation of porous metal–organic framework (MOF)–zeolite hybrid materials based on two 2D zeolites, namely, IPC-1P (Institute of Physical Chemistry - 1 Precursor) and the metal–organic framework ZIF-8 (Zeolitic Imidazolate Framework-8). Using the previously well-established assembly–disassembly–organization–reassembly method, the zeolite was (i) synthesized, (ii) hydrolyzed to a layered zeolite, (iii) the interlayer distance was increased using the swelling agent cetyltrimethylammonium chloride, and (iv) nanocrystals of ZIF-8 were grown stepwise on the zeolite surface but predominantly at the edges of the crystallites where the openings to the interlayer region are located. This selective MOF growth and attachment was facilitated by a combination of intercalation of the metal ions and the swelling agent between the zeolite layers. The influence of the solvent and the number of additional steps on the ZIF-8 growth on the zeolite was systematically investigated, and the synthesis protocol was successfully adapted to a further two-dimensional silicate RUB-18 (Ruhr-Universität Bochum - 18). This paves the way toward the controlled preparation of more MOF–zeolite hybrid materials, which might provide interesting properties for future applications.
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Pratiwi, Malisha Azra, Hifnalisa Hifnalisa, and Fikrinda Fikrinda. "Pengaruh Media Perbanyakan Berbasis Bahan Organik terhadap Produksi Inokulan Fungi Mikroriza Arbuskula." Jurnal Ilmiah Mahasiswa Pertanian 7, no. 2 (May 1, 2022): 696–704. http://dx.doi.org/10.17969/jimfp.v7i2.20127.
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Abstrak. Fungi mikoriza arbuskula (FMA) merupakan mikroorganisme yang berperan sebagai pupuk hayati, karena kemampuannya dalam meningkatkan serapan hara, serapan air dan daya tahan tanaman terhadap kekeringan. Media perbanyakan yang sesuai mempengaruhi kualitas inokulan FMA. Tujuan penelitian ini adalah untuk mengetahui pengaruh kombinasi media perbanyakan berbasis kompos terhadap produksi inokulan FMA Acaulospora tuberculata. Penelitian ini menggunakan rancangan acak kelompok non faktorial dengan tiga ulangan. Perlakuan yang diuji adalah zeolit 100% + NPK, zeolit+10% kompos, zeolit+20% kompos, zeolit+10% kompos yang diinokulasi fungi selulolitik (FS) Talaromyces pinophilus strain MR107, zeolit+ 20% kompos yang diinokulasi FS T. pinophilus strain MR107, zeolit +10% kompos yang diinokulasi FS Penicillium sp. isolate SR18, zeolit +20% kompos yang diinokulasi FS Penicillium sp. isolate SR18, zeolit+10% kompos yang diinokulasi FS Purpureocillium lilacinum, dan zeolit+20% kompos yang diinokulasi FS P. lilacinum. Hasil penelitian menunjukkan bahwa media perbanyakan berbasis kompos memberikan pengaruh sangat nyata terhadap jumlah spora FMA dan kolonisasi FMA pada akar tanaman inang. Perlakuan zeolit+20% kompos FS P. lilacinum menghasilkan jumlah spora FMA terbanyak sedangkan media zeolit + 10% kompos yang diinokulasi FS T. pinophilus strain MR107, zeolit + 20% kompos yang diinokulasi FS Penicillium sp. isolate SR18, zeolit + 10% kompos dan zeolit + N P K memberikan pengaruh yang sama terhadap tingkat kolonisasi FMA yang tertinggi. Hasil ini menunjukkan bahwa media kombinasi zeolit dan kompos dengan atau tanpa diperkaya fungi selulolitik efektif sebagai media perbanyakan dalam memproduksi spora FMA.Pengaruh Media Perbanyakan Berbasis Kompos Terhadap Produksi Inokulan Jamur Mikorhiza ArbuskularAbstract. Arbuscular mycorrhizal fungi (AMF) are microorganisms that act as biological fertilizers, because of their ability to increase nutrient uptake, water uptake and plant resistance to drought. Appropriate propagation media affects the quality of AMF inoculants. The purpose of this study was to determine the effect of a combination of compost-based propagation media on the production of Acaulospora tuberculata inoculants. This study used a non-factorial randomized block design with three replications. The treatments tested were zeolite 100% + NPK, zeolite + 10% compost, zeolite + 20% compost, zeolite + 10% compost inoculated with cellulolytic fungi (CS) Talaromyces pinophilus strain MR107, zeolite + 20% compost inoculated with CS T. pinophilus strain MR107, zeolite + 10% compost inoculated with CS Penicillium sp. isolate SR18, zeolite +20% compost inoculated with CS Penicillium sp. isolate SR18, zeolite+10% compost inoculated with CS Purpureocillium lilacinum, and zeolite + 20% compost inoculated with CS P. lilacinum. The results showed that compost-based propagation media had a very significant effect on the number of AMF spores and AMF colonization on host plant roots. Treatment of zeolite+20% compost inoculated with CS P. lilacinum produced the highest number of AMF spores while zeolite + 10% compost inoculated with CS T. pinophilus strain MR107, zeolite + 20% compost inoculated with CS Penicilliumsp. isolat SR18, zeolit +10% kompos dan zeolit + NPK memberikan pengaruh yang sama pada tingkat kolonisasi FMA tertinggi. Hasil ini menunjukkan bahwa kombinasi media zeolit dan kompos dengan atau tanpa pengayaan jamur selulolitik efektif sebagai media perbanyakan spora FMA.
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Maia, A. A. B., R. S. Angélica, and R. F. Neves. "Use of industrial kaolin waste from the Brazilian Amazon region for synthesis of zeolite A." Clay Minerals 46, no. 1 (March 2011): 127–36. http://dx.doi.org/10.1180/claymin.2011.046.1.127.
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AbstractProduction of kaolin for the paper-coating industry in the Brazilian Amazon region generates large amounts of waste, most of which is kaolinite. It is known that such materials can be used to synthesize zeolites. The use of kaolin waste for zeolite synthesis could, in principle, help social and economic development while providing valuable materials for industry. Additionally, there is a significant environmental appeal if such wastes could be used instead of new raw materials.This study focused on the production of zeolite A. Samples of the raw material were first calcined (700ºC/2 h) to obtain metakaolinite for further reaction with NaOH solution. Different parameters were evaluated to optimize the synthesis conditions of zeolite A. The results showed that zeolite A with a large degree of structural order was generally obtained as the only zeolitic product. The following synthesis conditions were used: temperature 110ºC, time 24 h and a Na/Al ratio of 1.36. Hydroxysodalite was also obtained under specific conditions.
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Schulman, Emily, Wei Wu, and Dongxia Liu. "Two-Dimensional Zeolite Materials: Structural and Acidity Properties." Materials 13, no. 8 (April 12, 2020): 1822. http://dx.doi.org/10.3390/ma13081822.
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Zeolites are generally defined as three-dimensional (3D) crystalline microporous aluminosilicates in which silicon (Si4+) and aluminum (Al3+) are coordinated tetrahedrally with oxygen to form large negative lattices and consequent Brønsted acidity. Two-dimensional (2D) zeolite nanosheets with single-unit-cell or near single-unit-cell thickness (~2–3 nm) represent an emerging type of zeolite material. The extremely thin slices of crystals in 2D zeolites produce high external surface areas (up to 50% of total surface area compared to ~2% in micron-sized 3D zeolite) and expose most of their active sites on external surfaces, enabling beneficial effects for the adsorption and reaction performance for processing bulky molecules. This review summarizes the structural properties of 2D layered precursors and 2D zeolite derivatives, as well as the acidity properties of 2D zeolite derivative structures, especially in connection to their 3D conventional zeolite analogues’ structural and compositional properties. The timeline of the synthesis and recognition of 2D zeolites, as well as the structure and composition properties of each 2D zeolite, are discussed initially. The qualitative and quantitative measurements on the acid site type, strength, and accessibility of 2D zeolites are then presented. Future research and development directions to advance understanding of 2D zeolite materials are also discussed.
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Panek, Rafał, Jarosław Madej, Lidia Bandura, and Grzegorz Słowik. "Recycling of Waste Solution after Hydrothermal Conversion of Fly Ash on a Semi-Technical Scale for Zeolite Synthesis." Materials 14, no. 6 (March 15, 2021): 1413. http://dx.doi.org/10.3390/ma14061413.
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Nowadays, using fly ash for zeolites production has become a well-known strategy aimed on sustainable development. During zeolite synthesis in a hydrothermal conversion large amount of post-reaction solution is generated. In this work, the solution was used as a substrate for Na-A and Na-X zeolites synthesis at laboratory and technical scale. Obtained materials were characterized using particle size analysis, X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), transmission electron microscopy (TEM), Fourier transformed infrared spectroscopy (FTIR), and nitrogen adsorption/desorption isotherm. Produced zeolites revealed high purity (>98%) and monomineral zeolitic phase composition. The SiO2 content was in the range 39–42% and 40–38%, whereas Al2O3 content was 23–22% and 25–26% for Na-X and Na-A, respectively. TEM and BET analyses revealed Na-X zeolite pores were almost identical to commercial 13X with SBET in the range 671–734 m2/g. FTIR indicated slight differences between materials obtained at laboratory and technical scale in Si-O-(Si/Al) bridges of the zeolitic skeleton. The results showed good replicability of the laboratory process in the larger scale. The proposed method allows for waste solution reusability with a view to highly pure zeolites production in line with circular economy assumptions.
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Yang, Li Ying, and Yi Qiu Tan. "Compacting Properties of Zeolite Based Warm Asphalt Mixture." Advanced Engineering Forum 5 (July 2012): 299–304. http://dx.doi.org/10.4028/www.scientific.net/aef.5.299.
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Warm asphalt mixture develops rapidly throughout the world in recent years. Zeolite based warm mix is one of the warm mixtures. In this paper, seven kinds of zeolites including six natural zeolites and one synthetic zeolite are selected. As warm mix additives, their physical properties such as density, water content and pore arrangements are tested respectively. To evaluate the compacting properties of zeolites based warm asphalt mixture, AC-20 mixture is designed and compaction is conducted. It shows that zeolites can reduce the compacting temperature for both Marshall and gyratory compaction. Temperature is the main factors which influence the compaction effect. Type of zeolite affects compaction to some extent. Marshall compaction is more sensitive to zeolite than gyratory compaction.
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Erofeev, Vladimir I., Sofiya N. Dzhalilova, Mikhail V. Erofeev, Vasilii S. Ripenko, and Vladimir P. Reschetilowski. "Conversion of the Propane–Butane Fraction into Arenes on MFI Zeolites Modified by Zinc Oxide and Activated by Low-Temperature Plasma." Molecules 25, no. 11 (June 11, 2020): 2704. http://dx.doi.org/10.3390/molecules25112704.
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The effect of modification of MFI zeolite 1–5 wt.% ZnO activated by plasma on acid and catalytic properties in the conversion of the propane–butane fraction into arenes was investigated. The high-silica zeolites with silicate module 45 were synthesized from alkaline alumina–silica gels in the presence of an ‘X-oil’ organic structure-forming additive. The modification of the zeolite with zinc was carried out by impregnating the zeolite granules in the H-form with an aqueous solution of Zn(NO3)2. The obtained zeolites were characterized by X-ray phase analysis and IR spectroscopy. It is shown that the synthesized zeolites belong to the high-silica MFI zeolites. The study of microporous zeolite-containing catalysts during the conversion of C3-C4 alkanes to aromatic hydrocarbons made it possible to establish that the highest yield of aromatic hydrocarbons is observed on zeolite catalysts modified with 1 and 3% ZnO and amount to 63.7 and 64.4% at 600 °C, respectively, which is 7.7–8.4% more than on the original zeolite. The preliminary activation of microporous zeolites modified with 1–5% ZnO and plasma leads to an increase in the yield of aromatic hydrocarbons from the propane–butane fraction; the maximum yield of arenes is observed in zeolite catalysts modified with 1 and 3% ZnO and activated by plasma, amounting to 64.9 and 65.5% at 600 °C, respectively, which is 8.9–9.5% more than on the initial zeolite. The activity of the zeolite catalysts modified by ZnO and activated by plasma show good agreement with their acid properties. Activation of the zeolites modified by 1 and 3% ZnO and plasma leads to an increase in the concentration of the weak acid sites of the catalyst to 707 and 764 mmol/g in comparison with plasma-inactivated 1 and 3% ZnO/ZKE-XM catalysts at 626 and 572 mmol/g, respectively.