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Journal articles on the topic 'Oxidační procesy'

Author: Grafiati

Published: 28 June 2021

Last updated: 2 February 2022

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1

Bilets, D. Yu, D. V. Miroshnichenko, P. V. Karnozhitskiy, and Yu V. Nikolaichuk. "Finding of kinetic characteristics of the process co-gasification of heavy coal tars with lignite and walnut shell." Chemistry, Technology and Application of Substances 3, no. 2 (November 1, 2020): 46–52. http://dx.doi.org/10.23939/ctas2020.02.046.

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Studied of co-gasification of heavy coal tars with lignite and walnut shell in the temperature ranged from 400 to 500 °С, the flow rate of oxidand (air) ranged from 0,0005 to 0,004 m3/min. It is established that the weigth loss of the sample mixtures in the gasification process has a S-shaped. Mathematical and graphical dependences of the influence of oxidant flow rate on the values of reaction rate constants and activation energy of gasification of experimental mixtures were developed.

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2

Yang, Cheng, Tian Yu Zhao, Li Juan Sun, Hong Song Song, and Da Bo Liu. "Process Conditions of Exfoliated Single-Layer Graphite." Advanced Materials Research 430-432 (January 2012): 350–54. http://dx.doi.org/10.4028/www.scientific.net/amr.430-432.350.

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The graphite was exfoliated by concentrated acid treatment, strong oxidants oxidation, high temperature rapid thermal shock process. Investigated in detail that the kind of oxidants, concentrated acid ratio, oxidation time affected on the graphite expansion rate. Experimental results (expansion, micro-structure observation and chemical structure analysis of graphite) showed that the optimum volume ratio of concentrated sulfuric acid and concentrated nitric acid was 4:1; the expansion rate was better that added oxidant KMnO4than added oxidant K2Cr2O7; The best oxidation time (concentrated acid treatment time) was 30~60 min.

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3

Liang, Yu-Feng, Xiaoyang Wang, Conghui Tang, Tao Shen, Jianzhong Liu, and Ning Jiao. "NHPI and palladium cocatalyzed aerobic oxidative acylation of arenes through a radical process." Chemical Communications 52, no. 7 (2016): 1416–19. http://dx.doi.org/10.1039/c5cc08945j.

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4

Gupta, Madhu, Amrita Srivastava, and Sheila Srivastava. "Sodium Periodate as a Selective Oxidant for Diclofenac Sodium in Alkaline Medium: A Quantum Chemical Approach." Bulletin of Chemical Reaction Engineering & Catalysis 15, no. 2 (July 6, 2020): 545–60. http://dx.doi.org/10.9767/bcrec.15.2.7555.545-560.

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Diclofenac sodium is a well known anti-inflammatory drug. It has also been proclaimed to exhibit adverse effects on aquatic animals through sewage and waste water treatment plants. Kinetic and mechanistic studies of the novel oxidation of diclofenac sodium (DFS) by sodium periodate were discussed with an emphasis on structure and reactivity by using kinetic and computational approach. The proposed work had been studied in alkaline medium at 303 K and at a constant ionic strength of 0.60 mol.dm−3. Formation of [2-(2,6-dicloro-phynylamino)-phenyl]-methanol as the oxidation product of DFS is confirmed with the help of structure elucidation. The active species of catalyst, oxidant and oxidation products were recognized by UV and IR spectral studies. Proton inventory studies in H2O−D2O mixtures had been shown the involvement of a single exchangeable proton of OH− ion in the transition state. All quantum chemical calculations were executed at level of density functional theory (DFT) with B3LYP function using 6-31G (d,p) basis atomic set for the validation of structure, reaction and mechanism. Molecular orbital energies, nonlinear optical properties, bond length, bond angles, reactivity, electrophilic and nucleophilic regions were delineated. Influence of various reactants on rate of chemical reaction were also ascertained and elucidated spectro-photometrically. Activation parameters have been assessed using Arrhenius-Eyring plots. A suitable mechanism consistent with observed kinetic results had been implicated and rate law deduced. Copyright © 2020 BCREC Group. All rights reserved

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5

Nurhadi, Mukhamad, Ratna Kusumawardani, Teguh Wirawan, Sumari Sumari, Sin Yuan Lai, and Hadi Nur. "Catalytic Performance of TiO2–Carbon Mesoporous-Derived from Fish Bones in Styrene Oxidation with Aqueous Hydrogen Peroxide as an Oxidant." Bulletin of Chemical Reaction Engineering & Catalysis 16, no. 1 (February 4, 2021): 88–96. http://dx.doi.org/10.9767/bcrec.16.1.9729.88-96.

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The catalytic performance of titania-supported carbon mesoporous-derived from fish bones (TiO2/CFB) has been investigated in styrene oxidation with aqueous H2O2. The preparation steps of (TiO2/CFB) catalyst involved the carbonization of fish bones powder at 500 °C for 2 h. followed by impregnation of titania using titanium(IV) isopropoxide (500 µmol) precursor, and calcined at 350 °C for 3 h. The physical properties of the adsorbents were characterized using Fourier transform infrared, X-ray diffraction (XRD), Scanning electron microscopy with energy dispersive X-ray (SEM-EDX), and nitrogen adsorption-desorption studies. The catalytic test was carried out using styrene oxidation with H2O2 as an oxidant at room temperature for 24 h. Its catalytic activity was compared with Fe2O3/CFB, CuO/CFB, TiO2, and CFB catalysts. It is demonstrated that the catalytic activity of TiO2/CFB catalyst has the highest compared to Fe2O3/CFB, CuO/CFB, TiO2, and CFB catalysts in the oxidation of styrene with styrene conversion ~23% and benzaldehyde selectivity ~90%. Kinetics of TiO2/CFB catalyzed oxidation of styrene has been investigated and mechanism for oxidation of styrene has been proposed. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

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6

Nurhadi, Mukhamad, Ratna Kusumawardani, and Hadi Nur. "Negative Effect of Calcination to Catalytic Performance of Coal Char-loaded TiO2 Catalyst in Styrene Oxidation with Hydrogen Peroxide as Oxidant." Bulletin of Chemical Reaction Engineering & Catalysis 13, no. 1 (April 2, 2018): 113. http://dx.doi.org/10.9767/bcrec.13.1.1171.113-118.

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The research of negative effect of calcination to catalytic performance of coal char-loaded TiO2 catalyst in styrene oxidation with hydrogen peroxide as oxidant has successfully done. The effects of calcination step to catalyst properties were characterized with Fourier Transform Infra Red (FTIR), X-ray Difraction (XRD), nitrogen adsorption, Field Emission Scanning Electron Microscopy (FESEM), and Transmission electron microscopy (TEM). The catalytic performance of the catalysts has been investigated in styrene oxidation with hydrogen peroxide as oxidant. The catalytic study showed the calcination step influenced to catalytic properties and could decrease the catalytic performance of coal char-loaded TiO2 catalyst in styrene oxidation. Copyright © 2018 BCREC Group. All rights reservedReceived: 20th April 2017; Revised: 8th September 2017; Accepted: 8th September 2017; Available online: 22nd January 2018; Published regularly: 2nd April 2018How to Cite: Nurhadi, M., Kusumawardani, R., Nur, H. (2018). Negative Effect of Calcination to Catalytic Performance of Coal Char-loaded TiO2 Catalyst in Styrene Oxidation with Hydrogen Peroxide as Oxidant. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (1): 113-118 (doi:10.9767/bcrec.13.1.1171.113-118)

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7

Liu, Yu, Qin Yu Gao, Lian Xin Liu, and Guang Xia Shi. "Study on Industry Process of the Rubber Anti-Oxidant RD." Applied Mechanics and Materials 79 (July 2011): 99–104. http://dx.doi.org/10.4028/www.scientific.net/amm.79.99.

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This paper studied on the industry synthesis process of anti-oxidant RD ((2,2,4- trimethyl-1,2-dihydro- quinoline polymer (C12H15N)n.n=2-4)) .The content of dimer, trimer and tetramer of RD were taken as the inspection targets, used the orthogonal design method, and take the ratios of keto-amine, the reaction time, the reaction temperatures and the ratios of catalyst acid-amine as inspect factors to optimized reaction condition. The result indicated that the best ratio of keto-amine is 6.5:1, the reaction time is 6 hours, the range of the reaction temperature is 115-120°C, the beat ratio of acid-amine is 0.2: 1 (the proportion is the concentration ratio for mole). Under the optimization conditions, the yield stability of RD.

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8

Liu, Yu, Qinyu Gao, Lianxin Liu, and Guangxia Shi. "Study on the Industrial Process of Rubber Anti-oxidant RD." Journal of the Korean Chemical Society 55, no. 5 (October 20, 2011): 830–34. http://dx.doi.org/10.5012/jkcs.2011.55.5.830.

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9

Chen, Qiaonan, Lan Sheng, Jiahui Du, Guan Xi, and Sean Xiao-An Zhang. "Photooxidation of oxazolidine molecular switches: uncovering an intramolecular ionization facilitated cyclization process." Chemical Communications 54, no. 40 (2018): 5094–97. http://dx.doi.org/10.1039/c8cc00983j.

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10

Wang, Shizong, and Jianlong Wang. "Comparative study on sulfamethoxazole degradation by Fenton and Fe(ii)-activated persulfate process." RSC Adv. 7, no. 77 (2017): 48670–77. http://dx.doi.org/10.1039/c7ra09325j.

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11

López-Galilea, I., S. Andueza, M. P de Peña, and C. Cid. "Antioxidant and pro-oxidant activity of coffee as affected by torrefacto roast." Czech Journal of Food Sciences 22, SI - Chem. Reactions in Foods V (January 1, 2004): S209—S211. http://dx.doi.org/10.17221/10662-cjfs.

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The addition of sugar at the end of the torrefacto roasting process could influence on the antioxidant and pro-oxidant properties of coffee because sugar is one of the main precursors of Maillard reaction. The aim of the work was to study and compare the antioxidant and pro-oxidant properties of some commercial roasted coffees which are selected to represent conventional roasted coffee and torrefacto roasted blends. When the percentage of torrefacto coffee was increased, the antioxidant activity increase and a slight tendency to decrease the pro-oxidant activity were observed. Moreover, a principal component analysis allowed to separate (a) brands by PC1 (46.9%) characterised by colour parameters defined by roast degree, and (b) torrefacto roast blends by PC2 (33.7%) characterised by antioxidant/pro-oxidant activity.

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12

Ma, Y. S., S. T. Huang, and J. G. Lin. "Degradation of 4-nitrophenol using the Fenton process." Water Science and Technology 42, no. 3-4 (August 1, 2000): 155–60. http://dx.doi.org/10.2166/wst.2000.0373.

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In this study, The Fenton process was applied as a pretreatment method to treat industrial wastewater containing 4-nitrophenol (4-NP). The effect of oxidant dosages on the decomposition of 4-NP and the reaction kinetics were investigated. More than 99% of 4-NP was readily decomposed when the reaction was carried out at oxidant concentrations of 5 mM H2O2 and 5 mg/L Fe2+ for 2 hours. The total nitrogenous compounds and the nitrogen gas evolved, accounted for 88% of the initial nitrogen concentration. However, the maximum DOC removal efficiency was 30.6%; and only 1/3 of 4-NP was mineralized to carbon dioxide by the Fenton process. 4-NP degradation profiles fitted well into a pseudo first-order kinetic equation; degradation rate constant (min-1) of 4-NP increased from 4.3×10-3 to 66.1×10-3 with increasing dosages of H2O2 and Fe2+. In addition, the t value was calculated for studying the significance of simulation by the t-test. It was found that the t value was greater than the value for 99% confidence. This result suggested that the 4-NP decomposition profile could be described by the pseudo first-order kinetic equation. Biodegradability of 4-NP before and after the reaction was 0.018 and 0.594, respectively.

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13

Shi, Jun, Jing Wang, Huifen He, Yang Lu, and Zhongxiang Shi. "Rodlike YMn2O5 Powders Derived from Hydrothermal Process Using Oxygen as Oxidant." Materials 13, no. 3 (February 10, 2020): 805. http://dx.doi.org/10.3390/ma13030805.

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A facile approach is proposed herein to fabricate YMn2O5 powders with the hydrothermal method with oxygen as an oxidant. The structure and morphology of the as-synthesized YMn2O5 powders were characterized by XRD, SEM, and high-resolution transmission electron microscopy (HRTEM). The results manifested that the main factors that affected the formation of the rod-like YMn2O5 structures were the stirring time, hydrothermal temperature, and hydrothermal time. The oxidation time in the air had a remarkable effect on the final product by oxidizing Mn2+ ions to Mn3+ ions and Mn4+ ions. The obtained YMn2O5 powder was single crystalline and possessed a nanorod morphology, where the growth direction was along the c axis. The possible formation mechanism involved a dissolution–crystallization mechanism. Under the 397 nm excitation, the Mn4+ ions exhibited an intense orange emission at 596 nm. The energy bandgap of YMn2O5 powders was 1.18 eV.

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14

Lin, Chia-Chang, and Li-Ting Lee. "Degradation of polyvinyl alcohol in aqueous solutions using UV/oxidant process." Journal of Industrial and Engineering Chemistry 21 (January 2015): 569–74. http://dx.doi.org/10.1016/j.jiec.2014.03.020.

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15

Pacholská, Tamara, Ivan Karpíšek, Jana Zuzáková, Vojtěch Kužel, Stanislav Gajdoš, Zuzana Nováková, Dana Vejmelková, Pavla Šmejkalová, and Vojtěch Kouba. "Eliminace mikropolutantů z vod kombinací oxidačních a sorpčních procesů v laboratorním měřítku." Entecho 4, no. 1 (June 2021): 15–20. http://dx.doi.org/10.35933/entecho.2021.003.

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Mikropolutanty v životním prostředí působí negativně na vodní ekosystémy a též představují potenciální riziko pro lidské zdraví. Zásadním zdrojem vnosu mikropolutantů do životního prostředí jsou městské ČOV, jejichž konvenční mechanicko-biologická technologie není na odstraňování mikropolutantů navržena. V této práci jsme testovali účinnost odstranění mikropolutantů řadou oxidačních (např. ozonizace, UV/H2O2, Fentonova reakce, borem dopovaná diamantová elektroda) a sorpčních (např. granulované aktivní uhlí GAU, zeolity) procesů. Účinnost odstranění vybraných léčiv (např. erythromycin, sulfamethoxazol, ibuprofen atd.) a metabolitů pesticidů (např. acetochlor ESA, metazachlor ESA) jsme testovali v jednorázových vsádkových testech. S přihlédnutím k ekonomickým i provozním parametrům byla pro následné testování v reálných podmínkách (poloprovozní měřítko) zvolena kombinace oxidace UV/H2O2 a sorpce na GAU. Mikropolutanty v modelové vodě byly úspěšně odstraněny z 91% (suma léčiv) a cca 100% (suma metabolitů pesticidů) při použití optimální dávky H2O2 5 mg/l a intenzity UV záření 4 kJ/m2 s následnou sorpcí na GAU. Tyto velmi slibné výsledky v současné době ověřujeme v pilotní jednotce pro dočištění reálného odtoku z městské ČOV. Abstract (EN) Micropollutants cause harm to aquatic ecosystems and can also negatively affect human health. Major sources of micropollutants input to aquatic environments are wastewater treatment plants due to their insufficient removal during the conventional mechanical-biological process. This study aimed to evaluate potential WWTP effluent post-treatment processes for the removal of selected pharmaceuticals and pesticides using oxidation (e.g., ozonization, UV/H2O2, Fenton, boron-doped diamond electrode) and sorption (e.g. granular activated carbon, zeolite) processes and their combinations. The removal of selected pharmaceuticals (e.g. erythromycin, sulphamethoxazole, ibuprofen) and pesticides (e.g. acetochlor ESA, metazachlor ESA) was tested in batch assays. The combination of UV/H2O2 and activated carbon adsorption was the most favorable in terms of removal efficiency and economic and operational parameters. This combination achieved the removal efficiencies of pharmaceuticals and pesticides of 91 and 100%, respectively, using an optimum H2O2 dose of 5 mg/L and UV intensity of 4 kJ/m2 followed by granular activated carbon adsorption. These promising results are currently adopted in a pilot-scale study for the post-treatment of a real WWTP effluent.

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Mancinelli, Andrea, Joan Albert, Xavier Ariza, Leoní A. Barrios, Jordi Garcia, Roberto Gómez, and Jaume Granell. "Access to indolines from primary phenylethylamines by an unexpected palladium-catalyzed C–H functionalization process." RSC Advances 9, no. 47 (2019): 27176–82. http://dx.doi.org/10.1039/c9ra05670j.

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17

Lu, Wenjun, Chong Mei, and Yixin Hu. "Visible-Light-Driven Oxidation of N-Alkylamides to Imides Using Oxone/H2O and Catalytic KBr." Synthesis 50, no. 15 (May 16, 2018): 2999–3005. http://dx.doi.org/10.1055/s-0036-1591575.

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Imides are prepared conveniently by visible-light-driven oxidations of various N-alkylamides under mild conditions. The majority of the reactions proceed efficiently by using Oxone as the oxidant in the presence of a catalytic amount of KBr in H2O/CH2Cl2 under irradiation by an 8 W white LED at room temperature. Experimental studies suggest that an imine, obtained from the substrate amide via a radical process, is the key intermediate.

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18

Samo, Saifullah, Ma Shu Yuan, and Bdran Sameh. "The Control of Fuel System for Combustion Piston Type Hopping Robot." Applied Mechanics and Materials 397-400 (September 2013): 1574–79. http://dx.doi.org/10.4028/www.scientific.net/amm.397-400.1574.

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Various hopping robots use the different methods to release energy for hop. The use of fuel with oxidant can provide enough potential energy for hopping by combustion. The fuel control system for combustion type hopping robot is presented. Maximum power of explosion can be obtained for high hop by mixing, fuel & oxidant in correct amount of ratio. The feedback fuel control system is presented which adjusts the ratio of fuel and oxidant to generate the desired pressure inside cylinder by controlling the fuel & oxidant pressures individually. The mixing process of fuel and oxidant takes place inside the cylinder. A simulation model of system in SIMULINK is established by using MATLAB software.

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19

Rahmanisa, Riang Anggraini, and I. Nyoman Widiasa. "Application of the Fenton Process in the Petroleum Refinery Spent Caustic Wastewater Treatment." Reaktor 20, no. 2 (June 30, 2020): 96–102. http://dx.doi.org/10.14710/reaktor.20.2.96-102.

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Spent caustic wastewater is produced from the scrubbing process using a caustic solution to absorb contaminants in the oil stream (hydrocarbon). Indonesia’s Petroleum Oil Refinery produces spent caustic wastewater from LPG and kerosene processing unit. Spent caustic wastewater has the characteristic of a strong odor with very high pH (12-14), containing dangerous pollutants such as phenol, aldehydes, mercaptans, and thiols that can be harmful to the human and environment. The Fenton process is used to treat spent caustic before being discharged to the environment. The Fenton process is one of AOPs (Advanced Oxidation Process) using Fe2+ as a catalyst and H2O2 as an oxidant to oxidize organic contaminants in wastewater. This study aims to determine the operating conditions of the Fenton Process with the target characteristics of treated spent caustic meet the WWTP (Waste Water Treatment Plant) inlet specifications and to make the design process of spent caustic treatment with the Fenton Process capacity of 10 m3/day. By operating at the H2O2/Fe (II) ratio of 1.8, the final target was achieved with COD of 810 ppm, ammonia of 22.84 ppm, sulfide of 60.93 ppm and phenol of 14.56 ppm. Total Capital Investment (TCI) for the design is US$ 2146701.89 whereas Total Manufacturing Cost of US$ 2089740.75.Keywords: spent caustic; refinery wastewater; Fenton process

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20

Seyedpour, S. M., I. Valizadeh, P. Kirmizakis, R. Doherty, and T. Ricken. "Optimization of the Groundwater Remediation Process Using a Coupled Genetic Algorithm-Finite Difference Method." Water 13, no. 3 (February 1, 2021): 383. http://dx.doi.org/10.3390/w13030383.

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In situ chemical oxidation using permanganate as an oxidant is a remediation technique often used to treat contaminated groundwater. In this paper, groundwater flow with a full hydraulic conductivity tensor and remediation process through in situ chemical oxidation are simulated. The numerical approach was verified with a physical sandbox experiment and analytical solution for 2D advection-diffusion with a first-order decay rate constant. The numerical results were in good agreement with the results of physical sandbox model and the analytical solution. The developed model was applied to two different studies, using multi-objective genetic algorithm to optimise remediation design. In order to reach the optimised design, three objectives considering three constraints were defined. The time to reach the desired concentration and remediation cost regarding the number of required oxidant sources in the optimised design was less than any arbitrary design.

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21

Nurfiningsih, Nurfiningsih, Ratnawati Ratnawati, and Aji Prasetyaningrum. "The Impact of Combination of Ozonation and Ultrasonication Process on Morphological and Chemical Properties of κ-Carrageenan." Reaktor 19, no. 2 (August 11, 2019): 49–53. http://dx.doi.org/10.14710/reaktor.19.2.49-53.

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Carrageenan application in the biomedical field is influenced by the size of molecular weight. Depolymerization process is needed for changing the high molecular weight (HMW) fraction of κ- carrageenan into low molecular weight fraction (LMW) of κ- carrageenan. Ozone is a powerful oxidant and considered for depolymerization of κ- carrageenan. This research was conducted as an investigation on the influence of the combination of ozonation and ultrasonication (OZ/US) on the chemical and morphological characteristics of κ-carrageenan. FTIR and Scanning electron microscopy (SEM) was used to determine the change of chemical and morphological characteristics of κ-carrageenan. The result of this study showed that there was no change of chemical properties of κ-carrageenan during OZ/US treatment. The sulfate content was obtained after OZ/US treatment tends to be stable. Nevertheless, the result of SEM analysis showed that there were changes on morphological characteristics of κ-carrageenan after OZ/US treatment. Keywords: ultrasonication, κ-carrageenan, ozonation, morphological, chemical

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22

Cristiano-Torres, Diana Vanessa, Yonnathan Osorio-Pérez, Liliam Alexandra Palomeque-Forero, Luis Ernesto Sandoval-Díaz, and Carlos Alexander Trujillo. "The action of vanadium over Y zeolite in oxidant and dry atmosphere." Applied Catalysis A: General 346, no. 1-2 (August 2008): 104–11. http://dx.doi.org/10.1016/j.apcata.2008.05.006.

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23

Dutta, Buddhadeb, Sreyashi Jana, Susmita Bhunia, Hisashi Honda, and Subratanath Koner. "Heterogeneous Baeyer–Villiger oxidation of cyclic ketones using tert-BuOOH as oxidant." Applied Catalysis A: General 382, no. 1 (June 30, 2010): 90–98. http://dx.doi.org/10.1016/j.apcata.2010.04.029.

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24

Winter, R. W., M. Ignatushchenko, O. A. Ogundahunsi, K. A. Cornell, A. M. Oduola, D. J. Hinrichs, and M. K. Riscoe. "Potentiation of an antimalarial oxidant drug." Antimicrobial Agents and Chemotherapy 41, no. 7 (July 1997): 1449–54. http://dx.doi.org/10.1128/aac.41.7.1449.

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In a previous report we described the synergistic antimalarial interaction between two structurally similar compounds, rufigallol and exifone. To explain this phenomenon, we proposed that exifone is transformed inside the parasitized erythrocyte into a xanthone with potent antimalarial properties. We speculated that the transformation process was induced by the prooxidant activity of rufigallol. On the basis of this model we hypothesized that exifone would act synergistically with other oxidant drugs. In the present study we have found a similar synergistic interaction between exifone and ascorbic acid (vitamin C) against both chloroquine-susceptible and multidrug-resistant strains of Plasmodium falciparum. The prooxidant activity of ascorbic acid against Plasmodium-infected erythrocytes is believed to result from an intraerythrocytic Fenton reaction occurring in the acidic food vacuole of the parasite. The hydroxyl radicals produced during this process are believed to attack exifone, which undergoes cyclodehydration to become 2,3,4,5,6-pentahydroxyxanthone (X5). Evidence presented to support this "xanthone hypothesis" includes the demonstration that the exifone ==> X5 transformation occurs readily in vitro under mildly acidic conditions in the presence of iron, ascorbic acid, and oxygen.

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Kačur, Ján, Milan Durdán, Marek Laciak, and Patrik Flegner. "Impact analysis of the oxidant in the process of underground coal gasification." Measurement 51 (May 2014): 147–55. http://dx.doi.org/10.1016/j.measurement.2014.01.036.

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26

Severeyns, A., D. E. De Vos, and P. A. Jacobs. "Development of a heterogeneous cis-dihydroxylation process with hydrogen peroxide as oxidant." Green Chemistry 4, no. 4 (July 11, 2002): 380–84. http://dx.doi.org/10.1039/b203741f.

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27

Lei, Zi-qiang, and Ren-ren Wang. "Oxidation of alcohols using H2O2 as oxidant catalyzed by AlCl3." Catalysis Communications 9, no. 5 (March 2008): 740–42. http://dx.doi.org/10.1016/j.catcom.2007.08.012.

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28

Liu, Yan Xiu, and Hua Song. "Removal of Thiophene from Simulated Oil by Catalytic Oxidation Using K₂FeO₄/ V₂O₅." Advanced Materials Research 183-185 (January 2011): 1568–72. http://dx.doi.org/10.4028/www.scientific.net/amr.183-185.1568.

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Oxidation extraction of thiophene from simulated oil by using K2FeO4as oxidant and methanol as extractant has been investigated. The effects of different catalyst, oxidant amount, catalyst amount, reaction temperature, reaction time, and extraction conditions were studied. This process is capable of decreasing the sulfur content of simulated oil from 100 mg•L-1to 17.8 mg•L-1at the optimal conditions. The results indicate that such a process could be an alternative to common hydrodesulfurization for deep desulfurization.

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Kamrani, M. S., K. Seifpanahi-Shabani, A. Seyed-Hakimi, G. A. M. Al, Sh Agarwa, and V. K. Gupta. "Degradation of cyanide from gold processing effluent by H2O2, NaClO and Ca(ClO)2 combined with sequential catalytic process." Bulgarian Chemical Communications 51, no. 3 (2019): 384–93. http://dx.doi.org/10.34049/bcc.51.3.5052.

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This work investigates the removal of cyanide as a noxious pollutant in the gold processing effluent (Aq-Dara mine, Takab, Iran) using H2O2, H2O2+Fe(II) (Fenton), H2O2+Cu(II), NaClO and Ca(ClO)2 oxidants. Implementation of purification operation was carried out by varying the parameters including pH, oxidant dosage, temperature and time of the reaction. The results show that the oxidants have the highest efficacy at pH 10-12, while the Fenton process has the highest efficiency at pH 8. The results confirm that Ca(ClO)2 is the best oxidant due to the shorter time, low reaction rate, high degradation of cyanide and low cost. The obtained results of response surface methodology optimization show that cyanide degradation has a direct relation to temperature, amount of oxidant, time and catalyst dosage parameters and has an inverse relation to pH. Also, the cyanide elimination efficiency is more than 99.5% and residual cyanide less than Environmental Protection Agency standards and 40% of the consumed water can be compensated by the effluent treatment and its return to the factory's processing circuit. Keywords: Oxidation Process; Gold Processing Effluents Treatment; Cyanide Degradation; Non-linear Kinetic Modeling, Response Surface Method.

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Kim, Joon-Soo, Woongsik Jang, and Dong Wang. "The Investigation of the Seebeck Effect of the Poly(3,4-Ethylenedioxythiophene)-Tosylate with the Various Concentrations of an Oxidant." Polymers 11, no. 1 (December 24, 2018): 21. http://dx.doi.org/10.3390/polym11010021.

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Poly(3,4-ethylenedioxythiophene)-tosylate (PEDOT-Tos) can be synthesized through an in situ polymerization and doping process with iron(III) p-toluenesulfonate hexahydrate as an oxidant. Both the Seebeck coefficient and the electrical conductivity were modified by varying the concentration of the oxidant. We investigated the effects of varying the concentration of the oxidant on the particle sizes and doping (oxidation) levels of PEDOT-Tos for thermoelectric applications. We demonstrated that an increase in the oxidant enabled an expansion of the particle sizes and the doping levels of the PEDOT-Tos. The modification of the doping levels by the concentration of the oxidant can provide another approach for having an optimal power factor for thermoelectric applications. De-doping of PEDOTs by reduction agents has been generally investigated for changing its oxidation levels. In this study, we investigated the effect of the concentration of the oxidant of PEDOT-Tos on the oxidation levels, the electrical conductivities and the Seebeck coefficients. As loading the oxidant of PEDOT-Tos, the Seebeck coefficient was compromised, while the electrical conductivity increased.

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31

Chavan, S. V., and A. K. Tyagi. "Nanocrystalline GdFeO3 via the gel-combustion process." Journal of Materials Research 20, no. 10 (October 2005): 2654–59. http://dx.doi.org/10.1557/jmr.2005.0337.

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Nanocrystalline GdFeO3 powder was synthesized by a combustion technique, using glycine as the fuel and the corresponding metal nitrates as oxidants. Five different molar ratios of fuel-to-oxidant were chosen to study the effect of fuel content on the phase formation and the powder properties. The powders after calcination were characterized by x-ray diffraction (XRD) and crystallite sizes calculated by x-ray line broadening. The crystallite sizes for the phase pure products after calcination at 600 °C were in the range 40–65 nm. The transmission electron microscopy observations clearly highlight the pronounced crystallinity for the propellant chemistry samples. The nature of the agglomerates was investigated by light scattering studies. The lattice thermal expansion behavior was also studied by high-temperature XRD.

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32

Lu, Jiqing, Mengfei Luo, Hao Lei, and Can Li. "Epoxidation of propylene on NaCl-modified silver catalysts with air as the oxidant." Applied Catalysis A: General 237, no. 1-2 (November 2002): 11–19. http://dx.doi.org/10.1016/s0926-860x(02)00062-5.

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Li, Ming Yu, Hai Bo Wu, Pei Pei Ma, Gang Cao, Lin Song, and Gang Ren. "Removal of Arsenic from Micro-Polluted Water by Enhanced Coagulation Process." Advanced Materials Research 573-574 (October 2012): 594–98. http://dx.doi.org/10.4028/www.scientific.net/amr.573-574.594.

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The removal of arsenic in micro-polluted water by enhanced coagulation with Poly Ferric Metasilicate (PFSS) was studied. The effects of dosage of PFSS , the dosage of oxidant and oxidize time on the removal efficiency of arsenic were discussed. Under the conditions of dosage of PFSS 0.065mmol/L, the residual concentration of arsenic in post-treated water was lower than 0.01 mg/L for raw water with initial concentration of arsenic 0.1 mg/L.

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34

Xiao, Xiao, Minghao Feng, and Xuefeng Jiang. "Transition-metal-free persulfuration to construct unsymmetrical disulfides and mechanistic study of the sulfur redox process." Chemical Communications 51, no. 20 (2015): 4208–11. http://dx.doi.org/10.1039/c4cc09633a.

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A sulfur redox process has been developed between sulfinate and thiosulfate, which efficiently affords diverse unsymmetrical disulfides and provides a new method to modify pharmaceuticals and natural products with this biologically active moiety without extra oxidant or reductant.

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35

Al-Duri, Bushra, Faihan Alsoqyani, and Iain Kings. "Supercritical water oxidation for the destruction of hazardous waste: better than incineration." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 373, no. 2057 (December 28, 2015): 20150013. http://dx.doi.org/10.1098/rsta.2015.0013.

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Supercritical water oxidation (SCWO) is an advanced process mainly employed for the treatment of hazardous stable wastes, otherwise treatable by incineration. It is based on the unique properties of water above its critical point ( T c =675 K, P c =22.2 MPa), making it a superior reaction medium for the destruction of all organics in the presence of oxygen. This work presents preliminary laboratory scale studies on SCWO of nitrogen (N)-containing hazardous hydrocarbons, with a view to enhancing the process performance, using available reagents and non-complex reactor design. This article investigates the destruction of dimethylformamide (DMF), carried out in a continuous (plug flow) reactor system. SCWO of DMF was enhanced by (i) a split-oxidant system, where stoichiometric oxidant was divided between two inlet ports at various ratios and (ii) the addition of isopropyl alcohol (IPA) as a co-fuel, premixed with the feedstock. Testing a range of temperatures, initial DMF concentrations, oxidant ratios, IPA ratios and oxidant split ratios, selected results were presented in terms of % total organic carbon and % N removal. Reaction kinetics were studied and showed a dramatic decrease in the activation energy upon adding IPA. Split-oxidant-feeding enhancement depended on the split ratio and secondary feed position.

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36

Zhao, Jiancan, Hong Fang, Jianlin Han, and Yi Pan. "Iron-catalyzed decarboxylative alkenylation of cycloalkanes with arylvinyl carboxylic acids via a radical process." Beilstein Journal of Organic Chemistry 9 (August 21, 2013): 1718–23. http://dx.doi.org/10.3762/bjoc.9.197.

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A Fe(acac)3-catalyzed decarboxylative coupling of 2-(aryl)vinyl carboxylic acids with cycloalkanes was developed by using DTBP as an oxidant through a radical process. This reaction tolerates a wide range of substrates, and products are obtained in good to excellent yields (71–95%). The reaction also shows excellent stereoselectivity, and only trans-isomers are obtained.

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Ho, S. E., N. Ide, and B. H. S. Lau. "S-allyl cysteine reduces oxidant load in cells involved in the atherogenic process." Phytomedicine 8, no. 1 (January 2001): 39–46. http://dx.doi.org/10.1078/0944-7113-00005.

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38

Bedekar, V., S. V. Chavan, and A. K. Tyagi. "Highly sinter-active nanocrystalline RE2O3 (RE = Gd, Eu, Dy) by a combustion process, and role of oxidant-to-fuel ratio in preparing their different crystallographic modifications." Journal of Materials Research 22, no. 3 (March 2007): 587–94. http://dx.doi.org/10.1557/jmr.2007.0101.

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Highly sinter-active powders of RE2O3 [rare earth (RE) = Gd, Eu, Dy] have been prepared using the corresponding metal nitrates as the oxidants, and glycine and citric acid as the fuels. Two different oxidant-to-fuel ratios, namely stoichiometric ratio and fuel-deficient ratio were used to explore the possibility of preparing different crystallographic modifications. By a careful control of oxidant-to-fuel ratio, nanocrystalline Eu2O3 and Gd2O3 could be prepared in cubic (C-type) as well as monoclinic (B-type) modifications. However, the high-temperature monoclinic modification could not be obtained for Dy2O3 due to a very high C-to-B-type phase transition temperature. The crystallite size, surface area, and sintering behavior were also studied for powders prepared using different oxidant-to-fuel ratios, and the results showed a remarkable correlation between different fuel contents and powder properties. Some of these powders resulted in pellets of nearly theoretical density. The sintered microstructure was studied by scanning electron microscopy.

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Kalis, Harijs, Maksims Marinaki, Uldis Strautins, and Maija Zake. "ON NUMERICAL SIMULATION OF ELECTROMAGNETIC FIELD EFFECTS IN THE COMBUSTION PROCESS." Mathematical Modelling and Analysis 23, no. 2 (April 18, 2018): 327–43. http://dx.doi.org/10.3846/mma.2018.020.

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This paper deals with a simpliﬁed model taking into account the interplay of compressible, laminar, axisymmetric ﬂow and the electrodynamical eﬀects due to Lorentz force’s action on the combustion process in a cylindrical pipe. The combustion process with Arrhenius kinetics is modelled by a single step exothermic chemical reaction of fuel and oxidant. We analyze non-stationary PDEs with 6 unknown functions: the 3 components of velocity, density, concentration of fuel and temperature. For pressure the ideal gas law is used. For the inviscid ﬂow approximation ADI method is used. Some numerical results are presented.

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Li, Xin, Mei Xiang Wan, and Cong Ju Li. "Synthesis and Characterization of Alkyl-Substituted Polyaniline by Using Ammonium Persulfate as both Oxidant and Dopant." Advanced Materials Research 1096 (April 2015): 147–55. http://dx.doi.org/10.4028/www.scientific.net/amr.1096.147.

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Poly (o-toluidine) (POT), poly (m-toluidine) (PMT) and poly (p-toluidine) (PPT) were chemically oxidized by ammonium persulfate (APS) as both oxidant and dopant through a very simple self-assembly process. The structure characterizations by elemental analysis, XPS and FTIR demonstrated that APS is served as both oxidant and dopant due to the proton acid produced during polymerization, which is proven by the decreasing pH value of the reaction solution along with the increase of polymerization time. Besides, the influences of the alkyl-substitution position on the molecular structure, polymerization process, morphology and electrical properties are also discussed.

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Yan, Qi Dong, Jun Xu, and Feng Xu. "Research of Catalytic Oxidation Synthesis of Cyclopentene to Glutaraldehyde." Advanced Materials Research 391-392 (December 2011): 1149–52. http://dx.doi.org/10.4028/www.scientific.net/amr.391-392.1149.

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The paper has studied the process of using H2O2 as oxidant and tungsten acid as catalyst, catalytic oxidation synthesis process of cyclopentene to glutaraldehyde and explored the main influence factors of the reaction, including the reaction time, reaction temperature, catalyst dosage and solvent. Furthermore, the quantitative analysis and qualitative analysis of the product was characterized by gas chromatography. The optimum synthetic condition was as follows: tertiary butanol as solvent, tungsten acid: boron anhydride(mass ratio)=1:1, 30%H2O2 as oxidant, the reaction temperature 35°C, the reaction time 4h, the yield of glutaraldehyde yield was 46%.

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42

Azmat, Rafia, Anum Khursheed, Ailyan Saleem, and Noshab Qamer. "Advanced catalytic oxidation process based on a Ti-permanganate (Mn/Ti-H+) reaction for the treatment of dye wastewater." RSC Advances 9, no. 64 (2019): 37562–72. http://dx.doi.org/10.1039/c9ra03045j.

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The newly developed advanced oxidation process is eco-friendly and cost-effective. The rate of reaction is independent of temperature, dye, oxidant, and catalytic and additive concentrations. Mineralization of dye is achieved in 60 minutes.

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43

Wei, Hua, Mao-Wen Xu, Shu-Juan Bao, Fan Yang, and Hui Chai. "Design and synthesis of carbonized polypyrrole-coated graphene aerogel acting as an efficient metal-free catalyst for oxygen reduction." RSC Adv. 4, no. 33 (2014): 16979–84. http://dx.doi.org/10.1039/c4ra00015c.

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44

Sheppard, T., C. D. Hamill, A. Goguet, D. W. Rooney, and J. M. Thompson. "A low temperature, isothermal gas-phase system for conversion of methane to methanol over Cu–ZSM-5." Chem. Commun. 50, no. 75 (2014): 11053–55. http://dx.doi.org/10.1039/c4cc02832e.

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45

Bagchi, Damayanti, Siddhi Chaudhuri, Samim Sardar, Susobhan Choudhury, Nabarun Polley, Peter Lemmens, and Samir Kumar Pal. "Modulation of stability and functionality of a phyto-antioxidant by weakly interacting metal ions: curcumin in aqueous solution." RSC Advances 5, no. 124 (2015): 102516–24. http://dx.doi.org/10.1039/c5ra21593e.

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46

Young, David J. "Diffusion in Internal Oxidation Reactions." Defect and Diffusion Forum 323-325 (April 2012): 283–88. http://dx.doi.org/10.4028/www.scientific.net/ddf.323-325.283.

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When an alloy component is selectively oxidised but cannot reach the surface quickly enough to form a scale, then internal oxidation results. In this process, a gas phase oxidant dissolves in an alloy and diffuses inwards, reacting with a dilute solute metal to precipitate metal oxide or carbide, etc. Penetration kinetics are parabolic, the rate being controlled by oxidant diffusion and the concentration of reacting metal. Rates are predicted from classical oxidation theory on the basis that the reaction product is exceedingly stable, no solute metal remains in the reacted alloy, and oxidant diffusion is via a solvent metal matrix. This paper is concerned with situations where these approximations fail: the development of low stability precipitates and the growth of elongated precipitates which allow interfacial diffusion of the oxidant. Effects on the rates of internal oxidation are discussed.

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47

Gonçalves, Gonçalo, Elvira Fortunato, J. I. Martins, and Rodrigo Martins. "Effect of Oxidant/ Monomer Ratio on the Electrical Properties of Polypyrrole in Tantalum Capacitors." Materials Science Forum 514-516 (May 2006): 43–47. http://dx.doi.org/10.4028/www.scientific.net/msf.514-516.43.

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In this work, the relation between oxidant/monomer ratio and the electrical conductivity of polypyrrole was studied using different ratios. We achieved a maximum value for electrical conductivity of 7.5 S/cm for a ratio of 2:1. We also developed a chemical dip-coating process to produce the cathode layer in tantalum capacitors. We obtained capacitances of about 80 µF after 8 cycles using the sequence Monomer/Oxidant.

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48

Yan, Qing Zhi, Xin Tai Su, Wen Feng Zhang, and Chang Chun Ge. "Process for Non-Agglomerated Nanometer-Sized Barium Titanate Powders by Sol-Gel Auto-Igniting Synthesis." Key Engineering Materials 280-283 (February 2007): 613–16. http://dx.doi.org/10.4028/www.scientific.net/kem.280-283.613.

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Non-agglomerated nano-sized BaTiO3 powders were prepared by a 3 step decomposition of barium titanyl citric acid chelate derived from Ba(NO3)2-TiO(NO3)2-citric acid-NH4NO3 based complex compound system. The 1st step was the thermal treatment of chelate wet gel at 150°C for 40min to remove water and non-bridging hydroxyl groups and to form expanded gel intermediate. The 2nd step was the decomposition of the organic fuel by igniting expanded gel intermediate at 300°C. The 3rd step was the formation of the high purity BaTiO3 by calcining the decomposed powders at 700°C for 2 hours. The most expanded gel intermediate was found to be a decisive factor for the elimination of hard agglomerate. In addition, the initial oxidant/fuel molar ratio was shown to strongly influence the characteristics of the powders thus obtained. The optimum oxidant/fuel value was 3 for obtaining non-agglomerated pure BaTiO3 powders with a particle size of 50 nm. The agglomerate degree of BaTiO3 powders was determined by particle morphology and uniformity of the green compact microstructure observed by field emission scanning electron microscopy and scanning electron microscope.

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You, Guirong, Dan Xi, Jian Sun, Liqiang Hao, and Chengcai Xia. "Transition-metal- and oxidant-free three-component reaction of quinoline N-oxides, sodium metabisulfite and aryldiazonium tetrafluoroborates via a dual radical coupling process." Organic & Biomolecular Chemistry 17, no. 43 (2019): 9479–88. http://dx.doi.org/10.1039/c9ob02106j.

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50

Mascolo, G., L. Spinosa, V. Lotito, G. Mininni, and G. Bagnuolo. "Lab-scale evaluations on formation of products of incomplete combustion in hazardous waste incineration: influence of process variables." Water Science and Technology 36, no. 11 (December 1, 1997): 219–26. http://dx.doi.org/10.2166/wst.1997.0414.

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Laboratory investigations have been carried out to study the influence of process failure modes on organics emission during the incineration of hazardous sludge. The thermal, temporal and fuel-oxidant mixing failure modes were tested. They were simulated by holding the first combustion temperature at 400°C and varying the after-burning one between 600 and 1100°C, the after-burning residence time between 1 and 3 s and the excess air between 30 and 160%. Results showed that the thermal failure mode is the most important factor controlling the number and concentration of emitted organics leading to the formation of over 70 compounds at after-burning temperature of 600°C. At higher after-burning temperatures emissions are controlled by the fuel-oxidant mixing failure mode and, only when the after-burning is 800°C and the oxygen is 160% over the stoichiometric value, by the temporal failure mode. Based on results obtained some suggestions for reducing emissions of toxic organics in full-scale incinerators are given.

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