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Journal articles on the topic 'Zirconia-based acid catalysts'

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Author: Grafiati

Published: 10 December 2022

Last updated: 29 January 2023

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1

Pothu, Ramyakrishna, Naresh Mameda, Harisekhar Mitta, Rajender Boddula, Raveendra Gundeboyina, Vijayanand Perugopu, Ahmed Bahgat Radwan, Aboubakr M. Abdullah, and Noora Al-Qahtani. "High Dispersion of Platinum Nanoparticles over Functionalized Zirconia for Effective Transformation of Levulinic Acid to Alkyl Levulinate Biofuel Additives in the Vapor Phase." Journal of Composites Science 6, no. 10 (October 10, 2022): 300. http://dx.doi.org/10.3390/jcs6100300.

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In recent years, functionalized metal oxides have been gaining popularity for biomass conversion to fuels and chemicals due to the global energy crisis. This study reports a novel catalyst based on noble metal immobilization on functionalized zirconia that has been successfully used in the production of biofuel alkyl levulinates (ALs) from lignocellulosic biomass-derived levulinic acid (LA) under vapor-phase. The wet impregnation method was used to immobilize Pt-metal nanoparticles on zirconia-based supports (silicotungstic acid zirconia, STA-ZrO2; sulfated zirconia, S-ZrO2; and tetragonal zirconia, t-ZrO2). A variety of physicochemical techniques were used to characterize the prepared catalysts, and these were tested under atmospheric pressure in continuous flow esterification of LA. The order of catalytic activity followed when ethyl levulinate was produced from levulinic acid via esterification: Pt/STA-ZrO2 ≫ Pt/S-ZrO2 ≫ Pt/t-ZrO2. Moreover, it was found that ALs synthesis from LA with different alcohols utilizing Pt/STA-ZrO2 catalyst followed the order ethyl levulinate ≫ methyl levulinate ≫ propyl levulinate≫ butyl levulinate. This work outlines an excellent approach to designing efficient catalysts for biofuels and value-added compounds made from biomass.

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2

Bakkali, Bouchra El, Guido Trautwein, Juan Alcañiz-Monge, and Santiago Reinoso. "Zirconia-supported 11-molybdovanadophosphoric acid catalysts: effect of the preparation method on their catalytic activity and selectivity." Acta Crystallographica Section C Structural Chemistry 74, no. 11 (October 18, 2018): 1334–47. http://dx.doi.org/10.1107/s2053229618013013.

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The oxidation of adamantane with hydrogen peroxide catalyzed by zirconia-supported 11-molybdovanadophosphoric acid is shown to be a suitable green route for the synthesis of adamantanol and adamantanone. This work evaluates how the catalyst activity and selectivity are affected by some of its preparative parameters, such as the method for supporting the catalytically active heteropoly acid over the zirconia matrix or the pretreatments applied to the resulting materials before being used as heterogeneous catalysts. Our results indicate that the most effective catalysts able to maintain their activity after several reaction runs are those prepared by following the sol-gel route, whereas the most selective catalysts are those obtained by impregnation methods. Moreover, the calcination temperature has also been identified as a relevant parameter influencing the performance of catalysts based on supported heteropoly acids. The increasing catalytic activity observed over several consecutive reaction runs has been attributed to the formation of peroxo derivatives of polyoxometalate clusters at the surface of the catalyst and their accumulation after each reaction cycle.

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3

Vasić, Katja, Gordana Hojnik Podrepšek, Željko Knez, and Maja Leitgeb. "Biodiesel Production Using Solid Acid Catalysts Based on Metal Oxides." Catalysts 10, no. 2 (February 17, 2020): 237. http://dx.doi.org/10.3390/catal10020237.

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The development of solid acid catalysts, especially based on metal oxides and different magnetic nanoparticles, gained much awareness recently as a result of the development of different nano-based materials. Solid acid catalysts based on metal oxides are promising for the (trans)esterification reactions of different oils and waste materials for biodiesel production. This review gives a brief overview of recent developments in various solid acid catalysts based on different metal oxides, such as zirconia, zinc, titanium, iron, tungsten, and magnetic materials, where the catalysts are optimized for various reaction parameters, such as the amount of catalyst, molar ratio of oil to alcohol, reaction time, and temperature. Furthermore, yields and conversions for biodiesel production are compared. Such metal-oxide-based solid acid catalysts provide more sustainable, green, and easy-separation synthesis routes with high catalytic activity and reusability than traditionally used catalysts.

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4

Reena, SS, SMZ Shamshuddin, VT Vasantha, and JQ D’Souza. "Synthesis of solketal over zirconia based acid catalysts." Bangladesh Journal of Scientific and Industrial Research 54, no. 1 (March 25, 2019): 31–38. http://dx.doi.org/10.3329/bjsir.v54i1.40728.

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Microwave assisted synthesis of ‘solketal’ over zirconia (ZrO2) and its modified forms (Mo(VI)/ZrO2, W(VI)/ZrO2 and V(V)/ZrO2) coated on honeycomb monoliths is reported. The solid acids were coated on honeycomb monoliths by ‘dip and dry’ method and characterized for their surface acidity, crystalinity, functionality, morphology and elemental analysis by using techniques such as NH3-Temperature programmed desorption (NH3-TPD), powder X-ray diffraction (PXRD), Fourier transform-infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and Inductively coupled plasma-optical emission spectroscopy (ICP-OES). The honeycomb monoliths coated with solid acids were employed as catalysts in the condensation of glycerol with acetone to synthesize solketal under microwave irradiation conditions. The reaction conditions such as molar ratio of the reactants (glycerol: acetone), reaction temperature, reaction time were studied to obtain highest possible yield of solketal with greater selectivity. The catalytic activity of honeycomb catalytic material was compared with the powder forms of the catalysts. 98% yield of solketal with 98% selectivity was achieved over Mo(VI)/ZrO2 coated on a honeycomb monolith in a very shorter reaction time of 8 min at 60 oC under microwave heating. These honeycomb catalytic material were found to be easily reactivable and reusable atleast for 6 reaction cycles. Hence, honeycomb catalysts were found to be efficient, economical and effective in the synthesis of value added chemical such as solketal. A possible mechanism for the formation of solketal is proposed. Bangladesh J. Sci. Ind. Res.54(1), 31-38, 2019

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5

Zhang, Wenwen, Zichun Wang, Jun Huang, and Yijiao Jiang. "Zirconia-Based Solid Acid Catalysts for Biomass Conversion." Energy & Fuels 35, no. 11 (May 19, 2021): 9209–27. http://dx.doi.org/10.1021/acs.energyfuels.1c00709.

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6

Stojkovic, N., M. Vasic, M. Marinkovic, M. Randjelovic, M. Purenovic, P. Putanov, and A. Zarubica. "A comparative study of n-hexane isomerization over solid acids catalysts: Sulfated and phosphated zirconia." Chemical Industry and Chemical Engineering Quarterly 18, no. 2 (2012): 209–20. http://dx.doi.org/10.2298/ciceq110602062s.

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Two series of zirconia based catalysts promoted with either sulfates or phosphates were prepared, calcined at different temperatures (600 and 700?C) and evaluated for the n-hexane isomerization reaction. The catalysts with different concentrations of sulfates or phosphates (4 or 10 wt. %) were characterized by BET, XRD, SEM methods, and total acidity was evaluated by using the Hammett indicators. Their final catalytic performances were correlated with their physical-chemical properties (surface, structural, textural and morphological). It was found that sulfated zirconia catalyst calcined at lower temperature showed the highest initial activity of all tested catalysts as the result of favorable total acidity, mesopore texture and structural properties. Somewhat lower activity of the sulfated catalyst calcined at higher temperature is related to the content of acid groups partially removed during thermal treatment, thus, lower total acidity, and also to less favorable textural and structural features. Negligible activity of phosphated zirconia catalysts is connected with low total acidity despite the positive status of particular property showing the complexity of the active phase/site formation in the catalyst.

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7

Huang, Yin-yan, Bi-ying Zhao, and You-chang Xie. "Preparation of zirconia-based acid catalysts from zirconia aerogel of tetragonal phase." Applied Catalysis A: General 172, no. 2 (September 1998): 327–31. http://dx.doi.org/10.1016/s0926-860x(98)00138-0.

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8

Luo, Wen, Qiongyao Zeng, Akram Ali Nasser Mansoor Al-Haimi, Ming Li, Lingmei Yang, Zhigang Sun, Shiyou Xing, Junying Fu, and Pengmei Lv. "Preparation and Performance of the Lipid Hydrodeoxygenation of a Nickel-Induced Graphene/HZSM-5 Catalyst." Catalysts 12, no. 6 (June 7, 2022): 627. http://dx.doi.org/10.3390/catal12060627.

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Graphene-encapsulated nickel nanoclusters are a feasible strategy to inhibit the nickel deactivation of nickel-based catalysts. In this work, graphene-encapsulated catalysts (Ni@C/HZSM-5) were prepared by a compression forming process, using pseudo-boehmite, Al2O3, and ZrO2 as binders. The pseudo-boehmite was gradually transformed from amorphous to crystalline alumina at high temperatures, which destroyed the nucleation of Ni@C. In contrast, the crystal-stabilized zirconia was more favorable for the nucleation of Ni@C. The extensive dispersion of alumina on the surface of HZSM-5 covers the acid sites of HZSM-5. In contrast, when zirconia was used as the binder, the binder existed in the form of the direct aggregation of ~100 nm zirconia spheres; this distribution form reduced better the damage of the binder to the acid site of the catalyst. Furthermore, the particle size of Ni crystals in the graphene-encapsulated catalysts decreased significantly (mostly <11 nm), and no evident agglomeration of nickel particles appeared. It was found that the stabilization of the metal interface delayed, to an extent, the accumulation rate of carbon deposits and, thus, postponed the deactivation of the acid sites. After 8 h of continuous reaction, the conversion of the traditional catalyst Ni/Z5+Zr dropped significantly to 60%. In contrast, the conversion of Ni@C catalysts prepared with ZrO2 remained above 90%. The regeneration test shows that air roasting could effectively remove carbon deposits and restore the catalyst activity.

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9

Checa, Manuel, Vicente Montes, Jesús Hidalgo-Carrillo, Alberto Marinas, and Francisco Urbano. "Influence of Boron, Tungsten and Molybdenum Modifiers on Zirconia Based Pt Catalyst for Glycerol Valorization." Nanomaterials 9, no. 4 (April 2, 2019): 509. http://dx.doi.org/10.3390/nano9040509.

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The influence of boron, tungsten and molybdenum modifiers on zirconia-based Pt catalyst was studied for glycerol valorization. Zirconia modified supports were prepared by impregnation of ZrO2 with either boric, silicontungstic or phosphomolybdic acids to obtain supports with enhanced Brönsted acidic properties. The modified supports were subsequently impregnated with chloroplatinic acid to obtain Pt-based catalysts. Pt incorporation resulted in the increase in Lewis acidity of the solids, being more significant for the Pt//W/ZrO2 catalyst. Reduced Pt catalysts were tested for the liquid-phase glycerol hydrogenolysis, observing a synergistic effect between catalyst acid sites and metal function that proved to be crucial in glycerol hydrogenolysis. The Pt//W/ZrO2 catalyst was the most active catalyst in this reaction, being the only leading to 1,3-PDO (45% sel., 160 °C) while Pt//Mo/ZrO2 is the best option for 1,2-PDO (49% sel., 180 °C). Reusability studies carried out for Pt//W/ZrO2 showed that catalytic activity dropped after the first use, remaining constant for the second and subsequent ones. Selectivity to reaction products also changes during reuses. Therefore, the selectivity to 1,2 PDO increases in the first reuse in detriment to the selectivity to n-propanol whereas the selectivity to 1,3-PDO remains constant along the uses. This behavior could be associated to the lixiviation of W species and/or catalyst fouling during reaction runs.

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10

García-Pérez, Diana, Maria Consuelo Alvarez-Galvan, Jose M. Campos-Martin, and Jose L. G. Fierro. "Influence of the Reduction Temperature and the Nature of the Support on the Performance of Zirconia and Alumina-Supported Pt Catalysts for n-Dodecane Hydroisomerization." Catalysts 11, no. 1 (January 11, 2021): 88. http://dx.doi.org/10.3390/catal11010088.

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Catalysts based on zirconia- and alumina-supported tungsten oxides (15 wt % W) with a small loading of platinum (0.3 wt % Pt) were selected to study the influence of the reduction temperature and the nature of the support on the hydroisomerization of n-dodecane. The reduction temperature has a major influence on metal dispersion, which impacts the catalytic activity. In addition, alumina and zirconia supports show different catalytic properties (mainly acid site strength and surface area), which play an important role in the conversion. The NH3-TPD profiles indicate that the acidity in alumina-based catalysts is clearly higher than that in their zirconia counterparts; this acidity can be attributed to a stronger interaction of the WOx species with alumina. The PtW/Al catalyst was found to exhibit the best catalytic performance for the hydroisomerization of n-dodecane based on its higher acidity, which was ascribed to its larger surface area relative to that of its zirconia counterparts. The selectivity for different hydrocarbons (C7–10, C11 and i-C12) was very similar for all the catalysts studied, with branched C12 hydrocarbons being the main products obtained (~80%). The temperature of 350 °C was clearly the best reduction temperature for all the catalysts studied in a trickled-bed-mode reactor.

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11

García-Pérez, Diana, Maria Consuelo Alvarez-Galvan, Jose M. Campos-Martin, and Jose L. G. Fierro. "Influence of the Reduction Temperature and the Nature of the Support on the Performance of Zirconia and Alumina-Supported Pt Catalysts for n-Dodecane Hydroisomerization." Catalysts 11, no. 1 (January 11, 2021): 88. http://dx.doi.org/10.3390/catal11010088.

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Catalysts based on zirconia- and alumina-supported tungsten oxides (15 wt % W) with a small loading of platinum (0.3 wt % Pt) were selected to study the influence of the reduction temperature and the nature of the support on the hydroisomerization of n-dodecane. The reduction temperature has a major influence on metal dispersion, which impacts the catalytic activity. In addition, alumina and zirconia supports show different catalytic properties (mainly acid site strength and surface area), which play an important role in the conversion. The NH3-TPD profiles indicate that the acidity in alumina-based catalysts is clearly higher than that in their zirconia counterparts; this acidity can be attributed to a stronger interaction of the WOx species with alumina. The PtW/Al catalyst was found to exhibit the best catalytic performance for the hydroisomerization of n-dodecane based on its higher acidity, which was ascribed to its larger surface area relative to that of its zirconia counterparts. The selectivity for different hydrocarbons (C7–10, C11 and i-C12) was very similar for all the catalysts studied, with branched C12 hydrocarbons being the main products obtained (~80%). The temperature of 350 °C was clearly the best reduction temperature for all the catalysts studied in a trickled-bed-mode reactor.

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12

Ruppert, Agnieszka M., Pierre Agulhon, Jacek Grams, Malgorzata Wąchała, Joanna Wojciechowska, Dariusz Świerczyński, Thomas Cacciaguerra, Nathalie Tanchoux, and Francoise Quignard. "Synthesis of TiO2–ZrO2 Mixed Oxides via the Alginate Route: Application in the Ru Catalytic Hydrogenation of Levulinic Acid to Gamma-Valerolactone." Energies 12, no. 24 (December 10, 2019): 4706. http://dx.doi.org/10.3390/en12244706.

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In this work, high surface area mono- and binary oxide materials based on zirconia and titania synthetized via the alginate route were applied as supports of ruthenium catalysts used in levulinic acid hydrogenation towards γ–valerolactone. The physicochemical properties of the catalysts were investigated using surface (like time-of-flight secondary ion mass spectrometry (ToF-SIMS), transmission electron microscopy (TEM)) and bulk techniques (temperature-programmed reduction (TPR), X-ray diffraction (XRD)). The obtained results exhibited that the proposed synthesis method allows for modification of the shape, morphology, and surface properties of the studied materials. These catalysts were tested in levulinic acid hydrogenation, in which catalytic support is known to be crucial. The results revealed that the titania-supported catalyst was the most active in the reaction mentioned above, while the highest mechanical stability was observed for zirconia-supported materials.

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13

SONG, XUEMIN, and ABDELHAMID SAYARI. "Sulfated Zirconia-Based Strong Solid-Acid Catalysts: Recent Progress." Catalysis Reviews 38, no. 3 (August 1996): 329–412. http://dx.doi.org/10.1080/01614949608006462.

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14

Serrao, Reena Saritha, S. Z. Mohamed Shamshuddin, and Joyce D'souza. "Catalytic Synthesis of Levulinate Esters over Zirconia and its Modified Forms Coated on Honeycomb Monoliths: Green Synthesis." Asian Journal of Chemistry 31, no. 9 (July 31, 2019): 1993–99. http://dx.doi.org/10.14233/ajchem.2019.22102.

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A series of solid acid catalysts such as ZrO2, Mo(VI)/ZrO2 and W(VI)/ZrO2 have been coated on honeycomb monoliths as well as synthesized in the powder forms and used as catalytic materials for synthesis of ethyl levulinate from levulinic acid and ethanol. These solid acids were characterized by BET, NH3-TPD/n-butyl amine back titration, FTIR, PXRD and SEM techniques. Effects of various reaction parameters towards the reaction performance were studied. The performance of the catalyst was tested based on nature of the catalyst (honeycomb coated or powder form), reaction time (1 to 5 h), molar ratio (1:1 to 1:12 levulinic acid to ethanol) and reusability of the catalytic material. An excellent yield (86-88 %) of ethyl levulinate was obtained under optimized conditions. An attempt is made to correlate the activity of the catalysts in this esterification reaction with their surface characteristics. The honeycomb monoliths coated with zirconia and its modified forms were found to be ecofriendly, cost-effective and reusable catalytic materials compared to their powder forms.

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15

Smolikov, M. D., O. V. Dzhikiya, L. I. Bikmetova, K. V. Kazantsev, I. V. Muromtsev, and A. S. Belyi. "The use of fluorinated alumina as a support of the sulfated zirconia catalyst for isomerization of hexane." Kataliz v promyshlennosti 21, no. 3 (May 17, 2021): 170–76. http://dx.doi.org/10.18412/1816-0387-2021-3-170-176.

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The study considers the effect of fluorine doping of the alumina matrix used for the synthesis of supported sulfated zirconia catalysts. Hydrofluoric acid served as a fluorinating agent. The addition of fluorine was shown to affect the textural characteristics of the Al2O3 matrix and hence the surface area of sulfated zirconia catalysts based on the doped systems. It was found that the introduction of fluorine into the catalysts increases their activity (the conversion of hexane) and the yield of high-octane isomer 2,2-dimethylbutane.

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16

Bergamaschi, V. S., F. M. S. Carvalho, W. R. Santos, and C. Rodrigues. "Synthesis and Characterization of Ni-Cu/ZrO₂ and Co-Cu/ ZrO₂ Catalysts Used for Ethanol Steam Reforming." Materials Science Forum 530-531 (November 2006): 619–24. http://dx.doi.org/10.4028/www.scientific.net/msf.530-531.619.

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Zirconia has received much attention as catalysts for its high surface area and acid-base property. The textural and acid-base properties of ZrO2 depend on both, the synthesis procedure and the calcinations temperature. The aim of the present study is the preparation and characterization of nickel/cupper/zirconia and cobalt/cupper/zirconia microspheres using hydrolysis process. This process is based on homogeneous hydrolysis of droplets of a concentrated ZrO2(NO3)2-urea solution after adding hexamethyletetramine. Gelation was conduced successfully and the gel spheres were dried at 80 °C. The dried gel spheres were thermally treated at 550 °C. Characterization of the samples was performed using X-ray diffraction (XRD), BET nitrogen adsorption, scanning electron microscopy (SEM), thermogravimetric (TGA) and UV-Vis spectroscopy. The performance of the microspheres was investigated as catalysts in steam reforming of ethanol. Theses catalysts exhibit a good selectivity for hydrogen.

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17

Rutkowska, Iwona A., and Pawel J. Kulesza. "Electrocatalytic oxidation of ethanol in acid medium: Enhancement of activity of vulcan-supported Platinum-based nanoparticles upon immobilization within nanostructured zirconia matrices." Functional Materials Letters 07, no. 06 (December 2014): 1440005. http://dx.doi.org/10.1142/s1793604714400050.

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Composite electrocatalytic materials that utilize carbon (Vulcan) supported Pt or PtRu nanoparticles dispersed within thin films of zirconia ( ZrO 2) are considered here for oxidation of such a biofuel as ethanol in acid medium. The systems were characterized using electrochemical techniques as well as transmission electron microscopy. The enhancement of activity was clearly evident upon comparison of the respective voltammetric and chronoamperometric current densities recorded (at room temperature in 0.5 mol dm-3 H 2 SO 4 containing 0.5 mol dm-3 ethanol) using the Vulcan supported Pt and PtRu catalysts in the presence and absence of zirconia. In all cases, the noble metal loading was the same, 100 μg cm-2. Apparently, the existence of large population of hydroxyl groups (originating from zirconia) in the vicinity of Pt -based catalyst, in addition to possible specific interactions between zirconia and the ruthenium component of PtRu , facilitated the oxidative removal (from Pt ) of the passivating (e.g., CO ) reaction intermediates (adsorbates). By utilizing carbon supported, rather than bare or unsupported, Pt or PtRu nanoparticles (dispersed within the semiconducting zirconia), the overall charge distribution at the electrocatalytic interface was improved.

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18

Reddy, Padigapati S., Putla Sudarsanam, Gangadhara Raju, and Benjaram M. Reddy. "Synthesis of bio-additives: Acetylation of glycerol over zirconia-based solid acid catalysts." Catalysis Communications 11, no. 15 (September 2010): 1224–28. http://dx.doi.org/10.1016/j.catcom.2010.07.006.

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19

Cui, Yuanyuan, Chao Wen, Xi Chen, and Wei-Lin Dai. "Highly selective one-pot continuous synthesis of 2-methoxyethanol via hydrogenation of dimethyl oxalate on Cu/ZrO2 catalysts with balanced acid sites." RSC Adv. 4, no. 59 (2014): 31162–65. http://dx.doi.org/10.1039/c4ra05014b.

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The distribution of 2-methoxyethanol and ethylene glycol can be controlled by regulating the surface acidity of copper based zirconia catalysts for hydrogenation of dimethyl oxalate. The yield of 2-methoxyethanol can reach 68% due to the synergistic effect of the surface acid site and active copper site.

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20

Dahl, Gregor Thomas, Jan-Dominik Krueger, Sebastian Döring, Horst Weller, and Tobias Vossmeyer. "Seeded Growth Synthesis of Zirconia@Gold Particles in Aqueous Solution." Nanomaterials 10, no. 6 (June 19, 2020): 1197. http://dx.doi.org/10.3390/nano10061197.

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Metal-ceramic composite particles are of increasing interest due to their potential applications in photonic metamaterials as well as next-generation catalysts. The zirconia-gold system has received little attention due to the lack of controllable preparation methods. Well-known methods for the deposition of gold nanoshells on silica spheres, however, should be adaptable for similar zirconia-based materials. Here, we present a novel synthetic approach to the well-controlled deposition of gold on the surface of sol-gel derived zirconia mesoparticles by a stepwise method involving the immobilization of gold nanoparticles and repeated seeded-growth steps. We show that the immobilization efficiency is strongly enhanced by acidification with hydrochloric acid and additional employment of aminomethylphosphonic acid as coupling agent. The optimum conditions are identified and the subsequent incremental growth by seeded reduction of gold is demonstrated. The results shed light on the parameters governing the preparation of zirconia@gold composite particles and our synthetic approach provides a promising tool for future developments in complex nanomaterials design.

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Nayebzadeh, Hamed, Abbas Rohani, Aliakbar Sistani, Ali Hassanpour, and Jabbar Gardy. "Modelling and Optimisation of the Sol-Gel Conditions for Synthesis of Semi-Hexagonal Titania-Based Nano-Catalyst for Esterification Reaction." Catalysts 12, no. 2 (February 20, 2022): 239. http://dx.doi.org/10.3390/catal12020239.

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Design and fabrication of a catalyst with the highest activity can be achieved by optimising the synthesis conditions. In this study, the sol-gel synthesis conditions of citric acid concentration, gelling temperature, complex time, and calcination temperature were studied for the preparation of a novel semi-hexagonal calcium/titania-zirconia nano-catalyst used in the esterification reaction. After synthesis of around 24 samples at various conditions, their activity was tested in the esterification reaction and the results were analysed by multi-layer perceptron (MLP) and support vector machine (SVM) models. Both models predicted the actual data with high coefficients of determination, and indicated that the calcination temperature has the most influence on the activity of the prepared semi-hexagonal calcium/titania-zirconia nano-catalyst for the esterification reaction. Moreover, the genetic algorithm (GA) was utilised for optimising the preparation conditions based on the SVM model, due to its higher generalisation capability for prediction. The prepared nano-catalysts under the optimum conditions of 1.42 acid ratio, gelling temperature of 72 °C, complex time of 2.65 h, and calcination temperature of 487 °C showed good crystalline structure and metal–metal and metal–oxygen cation bonding. Finally, the fabricated catalyst had a high surface area (276.5 m2/g) with 3.5 nm pore diameter and almost uniform particle size (80–110 nm) distribution, leading to a high conversion of 97.6% in the esterification reaction, with good catalytic stability up to five times.

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22

Melián-Rodríguez, Saravanamurugan, Meier, Kegnæs, and Riisager. "Ru-Catalyzed Oxidative Cleavage of Guaiacyl Glycerol--Guaiacyl Ether-a Representative -O-4 Lignin Model Compound." Catalysts 9, no. 10 (October 3, 2019): 832. http://dx.doi.org/10.3390/catal9100832.

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The introduction of efficient and selective catalytic methods for aerobic oxidation of lignin and lignin model compounds to aromatics can extend the role of lignin applications in biorefineries. The current study focussed on the catalytic oxidative transformation of guaiacyl glycerol--guaiacyl ether (GGGE)–a -O-4 lignin model compound to produce basic aromatic compounds (guaiacol, vanillin and vanillic acid) using metal-supported catalysts. Ru/Al2O3, prepared with ruthenium(IV) oxide hydrate, showed the highest yields of the desired products (60%) in acetonitrile in a batch reactor at 160 C and 5-bar of 20% oxygen in argon. Alternative catalysts containing other transition metals (Ag, Fe, Mn, Co and Cu) supported on alumina, and ruthenium catalysts based on alternative supports (silica, spinel, HY zeolite and zirconia) gave significantly lower activities compared to Ru/Al2O3 at identical reaction conditions. Moreover, the Ru/Al2O3 catalyst was successfully reused in five consecutive reaction runs with only a minor decrease in catalytic performance.

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23

Rutkowska, Iwona A. "Enhancement of Oxidation of Formic Acid in Acid Medium on Zirconia-Supported Phosphotungstate-Decorated Noble Metal (Pd, Pt) Nanoparticles." Australian Journal of Chemistry 69, no. 4 (2016): 394. http://dx.doi.org/10.1071/ch15721.

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Palladium and platinum nanoparticles have been modified at sub-monolayer level with Keggin-type phosphododecatungstate (by spontaneous adsorption of H3PW12O40) and considered as catalysts for the electrooxidation of formic acid in sulfuric acid electrolyte. The presence of phosphotungstate adsorbates has been confirmed using Fourier transform infrared spectroscopy (by reflectance). The enhancement effect (described in terms of the oxidation current increases) is even more pronounced when the catalytic centres have been supported on nanostructured ZrO2. In the case of Pd catalysts, a large population of hydroxyl groups and a high mobility of interfacial protons (on zirconia) seem to favour the direct oxidation path to CO2, whereas in the case of Pt-based systems, the enhancement effect is related to the oxidative removal of otherwise passivating CO adsorbates (indirect oxidation path). The role of polytungstate adsorbates on Pd or Pt nanoparticles relates to their ability to interact competitively with the CO adsorbates at noble metal catalytic sites (‘third-body’ effect).

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24

Omota, F., A. C. Dimian, and A. Bliek. "Fatty acid esterification by reactive distillation: Part 2—kinetics-based design for sulphated zirconia catalysts." Chemical Engineering Science 58, no. 14 (July 2003): 3175–85. http://dx.doi.org/10.1016/s0009-2509(03)00154-4.

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Aleem, S. A., N. Asikin-Mijan, A. S. Hussain, C. H. Voon, A. Dolfi, S. Sivasangar, and Y. H. Taufiq-Yap. "Catalytic ketonization of palmitic acid over a series of transition metal oxides supported on zirconia oxide-based catalysts." RSC Advances 11, no. 51 (2021): 31972–82. http://dx.doi.org/10.1039/d0ra10963k.

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Dhawan, Himanshi, James Woodford, Natalia Semagina, and Marc Secanell. "Impact of Different Supports on the Performance of Ir Oxide Based Catalysts Synthesized Using Incipient Wetness Method." ECS Meeting Abstracts MA2022-02, no. 50 (October 9, 2022): 2598. http://dx.doi.org/10.1149/ma2022-02502598mtgabs.

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Development of an active and durable catalyst for oxygen evolution reaction (OER) is a pivotal part of designing an efficient PEM water electrolyser. Iridium is one of the best available catalysts because of its corrosion resistance and activity [1]. Use of Ir is however, limited by its scarcity, limited durability and high cost. Its deposition on a support is a popular way to improve the available surface area, activity and stability [2]. For applications in acidic water electrolysis, supports with the highest chemical resistance and conductivity are preferred. While different methods have been studied to impregnate a support with catalyst nanoparticles, such as Adams’s fusion method and polyol method, their scalability remains questionable due to intensive resource requirements. In this work, Ir oxide based supported catalysts have been synthesized using the incipient wetness method (IWM), one of the most commonly used method of catalyst synthesis in the industry due to its ease of scalability, limited resource requirement and the opportunity to explore the effect of strong metal support interactions. This method however has not been discussed in literature. In this study, Ir oxide (IrOx) (Ir loading on support = 20 wt. percent) was dispersed on commercial supports (ZrO2, Nb2O5, Ta2O5, ATO) using H2IrCl6.xH2O precursor (99.9% trace metal basis, Sigma Aldrich). The catalysts were calcined at 400oC for 2 h in a muffle furnace to produce Ir oxide based catalysts. Electrochemical measurements were carried out on a standard rotating-disk electrode (RDE) system (PINE Research MSR Rotator), and a three-electrode electrochemical cell in 1.0 M sulfuric acid electrolyte (H2SO4 optima grade, Fisher Scientific). The performance of the aforementioned supported Ir oxide catalyst was compared among themselves, and to benchmark commercial catalysts (Umicore Ir Black and IrOx TKK) using metrics such as mass normalized activity (A/g-1 Ir), ECSA normalized activity (mA/cm2 Ir ECSA), Tafel slope (mV/dec) and charge transfer resistance (Rct) measured during the electrochemical test. It was observed that the activity of IrOx/ZrO2 (415 A/gIr, 5.2 mA/cm2 Ir ECSA) was the best among all the 4 impregnated catalysts, and was in fact, more than an order of magnitude greater than that of IrOx/ATO (30 A/gIr, 0.3 mA/cm2 Ir ECSA) at a potential of 1.53 VRHE. A significant drop in the Tafel slope measured in the potential range of 1.45-1.55 VRHE was observed upon changing the support from ATO (80 mV/dec) to ZrO2 (60 mV/dec) hinting towards a change in the reaction mechanism. IrOx/ATO was used as a baseline due to prevalent recognition of ATO as an excellent support for OER catalysts in the literature. Upon comparison with commercial benchmark catalysts it was observed that the Ir ECSA normalized activity of IrOx/Nb2O5, IrOx/Ta2O5, IrOx/ZrO2 surpasses both Umicore Ir black ( 2.23 mA/cm2 Ir ECSA) and IrOx TKK (1.23 mA/cm2 Ir ECSA) with IrOx/ZrO2 providing the highest activity. While Yttria-stabilized zirconia (YSZ) has been a popular choice as an electrolyte and anode for high temperature SOFC due to its non-reducing nature, high thermal stability and mechanical strength, and acceptable oxygen ion conductivity [3], its application in PEM water electrolysis as catalyst support has not been discussed. In this work, we focus on finding the causes for superior performance of ZrO2 as a support for Ir oxide based OER reaction in acidic conditions through the lens of electrocatalysis. References: [1] X. Li, X. Hao, A. Abudula, and G. Guan, “Nanostructured catalysts for electrochemical water splitting: Current state and prospects,” Journal of Materials Chemistry A, vol. 4, no. 31, pp. 11973–12000, 2016, doi: 10.1039/c6ta02334g. [2] H. Dhawan, M. Secanell, and N. Semagina, “State-of-the-art iridium-based catalysts for acidic water electrolysis: a minireview of wet-chemistry synthesis methods,” Jan. 01, 2021. https://www.ingentaconnect.com/content/matthey/jmtr/pre-prints/content-jm_jmtr_semagapr21 (accessed Mar. 26, 2021). [3] T. K. Maiti et al., “Zirconia- and ceria-based electrolytes for fuel cell applications: critical advancements toward sustainable and clean energy production,” Environ Sci Pollut Res, vol. 29, no. 43, pp. 64489–64512, Sep. 2022, doi: 10.1007/s11356-022-22087-9. Figure 1

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Tatar, Dalibor, Jelena Kojčinović, Berislav Marković, Aleksandar Széchenyi, Aleksandar Miletić, Sándor Balázs Nagy, Szilveszter Ziegenheim, et al. "Sol-Gel Synthesis of Ceria-Zirconia-Based High-Entropy Oxides as High-Promotion Catalysts for the Synthesis of 1,2-Diketones from Aldehyde." Molecules 26, no. 20 (October 10, 2021): 6115. http://dx.doi.org/10.3390/molecules26206115.

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Efficient Lewis-acid-catalyzed direct conversion of aldehydes to 1,2-diketones in the liquid phase was enabled by using newly designed and developed ceria–zirconia-based high-entropy oxides (HEOs) as the actual catalysts. The synergistic effect of various cations incorporated in the same oxide structure (framework) was partially responsible for the efficiency of multicationic materials compared to the corresponding single-cation oxide forms. Furthermore, a clear, linear relationship between the Lewis acidity and the catalytic activity of the HEOs was observed. Due to the developed strategy, exclusively diketone-selective, recyclable, versatile heterogeneous catalytic transformation of aldehydes can be realized under mild reaction conditions.

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Neves, Patrícia, Patrícia A. Russo, Auguste Fernandes, Margarida M. Antunes, João Farinha, Martyn Pillinger, Maria Filipa Ribeiro, José E. Castanheiro, and Anabela A. Valente. "Mesoporous zirconia-based mixed oxides as versatile acid catalysts for producing bio-additives from furfuryl alcohol and glycerol." Applied Catalysis A: General 487 (October 2014): 148–57. http://dx.doi.org/10.1016/j.apcata.2014.08.042.

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Stošić, Dušan, Simona Bennici, Jean-Luc Couturier, Jean-Luc Dubois, and Aline Auroux. "Influence of surface acid–base properties of zirconia and titania based catalysts on the product selectivity in gas phase dehydration of glycerol." Catalysis Communications 17 (January 2012): 23–28. http://dx.doi.org/10.1016/j.catcom.2011.10.004.

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Ksila, Wafa, Mohamed Kadri Younes, Abdelhamid Ghorbel, and Alain Rives. "Characterization and catalytic reactivity of xerogel catalysts based on mesoporous zirconia doped with telluric acid prepared by sol–gel method: mechanistic study of acetic acid esterification with benzyl alcohol." Journal of Sol-Gel Science and Technology 99, no. 2 (July 8, 2021): 376–90. http://dx.doi.org/10.1007/s10971-021-05580-4.

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Yasufuku, Daichi, Mayumi Nagayama, Kazunari Sasaki, and Akari Hayashi. "(PEFC&E 2022 Student Poster Award Winner - 2nd Place) Investigation of a Correlation Between IV Performance and Cathode Structure for MEAs Using Mesoporous Carbon Supports." ECS Meeting Abstracts MA2022-02, no. 42 (October 9, 2022): 1557. http://dx.doi.org/10.1149/ma2022-02421557mtgabs.

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Introduction Polymer Electrolyte Fuel Cell (PEFC) is a promising energy technology for a future decarbonized society. PEFC is composed of porous electrode catalyst layers, which largely determines current-voltage (IV) performance. However, the optimal structure of porous catalyst layers is still unknown. Carbon supports are the main component to build up such porous structure. Mesoporous carbon (MC) supports are recently paid more attention to since they are used in Toyota’s fuel cell vehicles, MIRAI. We are also studying MC whose diameter is about 10 nm. Therefore, we are interested in a correlation between IV performance and the structure of catalyst layers based on MC supports. The aim of this study is to clarify the optimal structure of cathode catalyst layers for high IV performance. In this study, we synthesized two types of MC, MC bulk and fibers, and evaluated the IV performance and cathode structure of MC based cathode catalyst layers. Experimental MC bulk was prepared based on self-organization of Pluronic F127 and carbon precursors (resorcinol, formaldehyde, and triethyl orthoacetate). They were mixed in the acid solution, and then the supernatant was removed after centrifugation. The remaining portion was heated in the oven for polymerization of carbon precursors. The resulting material was heated by stepwise in the oven under the nitrogen atmosphere in order to decompose Pluronic F127 and carbonized precursors. MC fibers were made by electrospinning of the similar precursor solution mentioned in the above, but for electrospinning phloroglucinol instead of resorcinol was in use, and PVA was added. Then, after MC bulk and fibers were milled by hands or zirconia balls, Pt nanoparticles were deposited on MC supports by using Pt(acac)2 as a precursor. MEAs with 1cm2 electrodes were fabricated by spray-printing of catalyst dispersions on the Nafion film. Prepared MC based catalysts were used for the cathode, and 46.5% Pt/KB (TEC10E50E) was used for the anode. Results and discussion IV performance of MEAs using MC based cathodes was evaluated and compared to that of a standard MEA. MEA with MC bulk support showed slightly lower IV performance than that of standard MEA. By analyzing each overvoltage separately, ohmic overvoltage was found to be a biggest problem, and low concentration overvoltage was realized as an advantage. In order to find out the reason of low concentration overvoltage, the structure of cathode layers was evaluated using FIB-SEM. The 300 cross-sectional SEM images were obtained by slicing cathodes every 10 nm, and the cathode was reconstructed into a three dimensional image. As a result, the size of MC support was found to be much larger than that of KB. When pore diameter distribution was evaluated based on the reconstructed image, as shown in Figure 1, rather large pores expressed in red in the figure was observed for MC bulk based cathode probably owing to large MC particles. The low concentration most likely comes from the existence of such large pores. In this structural analysis, the analysis of mesopores is not included, and so in reality mesopores might have contributed to lowering concentration overvoltage. Similar analyses were done for MC fiber based cathodes. We have found that the IV performance and structure of cathodes is rather influenced by the milling processes, which will be discussed in detail. Figure 1

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Tosoni, Sergio, Hsin-Yi Tiffany Chen, Antonio Ruiz Puigdollers, and Gianfranco Pacchioni. "TiO 2 and ZrO 2 in biomass conversion: why catalyst reduction helps." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 376, no. 2110 (November 27, 2017): 20170056. http://dx.doi.org/10.1098/rsta.2017.0056.

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Biomass refers to plant-based materials that are not used for food or feed. As an energy source, lignocellulosic biomass (lignin, cellulose and hemicellulose) can be converted into various forms of biofuel using thermal, chemical and biochemical methods. Chemical conversion implies the use of solid catalysts, usually oxide materials. In this context, reducible oxides are considered to be more active than non-reducible oxides. But why? Using density functional theory DFT + U calculations with the inclusion of dispersion forces, we describe the properties of anatase TiO 2 , a reducible oxide, and tetragonal ZrO 2 , a non-reducible oxide, the (101) surfaces in this context. In particular, we focus on the role of surface reduction, either by direct creation of oxygen vacancies via O 2 desorption, or by treatment in hydrogen. We show that the presence of reduced centres on the surface of titania or zirconia (either Ti 3+ or Zr 3+ ions, or oxygen vacancies) results in lower barriers and more stable intermediates in two key reactions in biomass catalytic conversion: ketonization of acetic acid (studied on ZrO 2 ) and deoxygenation of phenol (studied on TiO 2 ). We discuss the role of Ru nanoparticles in these processes, and in particular in favouring H 2 dissociation and hydrogen spillover, which results in hydroxylated surfaces. We suggest that H 2 O desorption from the hydroxylated surfaces may be a relevant mechanism for the regeneration of oxygen vacancies, in particular on low-coordinated sites of oxide nanoparticles. Finally, we discuss the role of nanostructuring in favouring oxide reduction, by discussing the properties of ZrO 2 nanoparticles of diameter of about 2 nm. This article is part of a discussion meeting issue ‘Providing sustainable catalytic solutions for a rapidly changing world’.

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Rangganita, F. R., L. Hermida, A. Angraeni, and D. Khoirunnisa. "Reusability Study of Sulfated Zirconia Functionalized SBA-15 Catalyst for Biolubricant Oil Production from Oleic Acid." Journal of Engineering and Scientific Research 1, no. 1 (June 13, 2019): 46. http://dx.doi.org/10.23960/jesr.v1i1.10.

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Sulfated zirconia functionalized SBA-15 catalsyt (SZr-SBA-15) was prepared byreacting SBA-15 with Zirkoniumoxychloride and urea at 90oC to form ZrO2-SBA-15. Then, ZrO2-SBA-15 was reacted with H2SO4 at room temperature to produceSZr-SBA-15 catalsyt.. The catalyst was characterized in terms of adsorptiondesorption nitrogen analysis, SEM-EDX and FTIR. Based on SEM-EDX andadsorption-desorption nitrogen analysis results, it was found that Zr had beenincorporated in SBA-15. By using the SZr-SBA-15 catalyst, esterification reactionof oleic acid with TMP to produce biolubricant oil of Trimethylolpropanetrioleatachieved 85% oleic acid conversion and selectivity of 63,7%. Reusability study ofSZr-SBA-15 catalyst was carried out for 3 rounds of reaction. It was found that thecatalyst could be used up to 3 rounds without significant decrease in activityKeywords: biolubricant oil, catalyst reusability, sba-15, sulfated zirconia.

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Pandey, Rajesh K., Sharda P. Dagade, Mohan K. Dongare, and Pradeep Kumar. "Synthesis of Carbamates Using Yttria-Zirconia Based Lewis Acid Catalyst." Synthetic Communications 33, no. 23 (December 1, 2003): 4019–27. http://dx.doi.org/10.1081/scc-120026337.

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Lin, Jinchi, Haiyan Song, Xiaoru Shen, Binju Wang, Shunji Xie, Weiping Deng, Deyin Wu, Qinghong Zhang, and Ye Wang. "Zirconia-supported rhenium oxide as an efficient catalyst for the synthesis of biomass-based adipic acid ester." Chemical Communications 55, no. 74 (2019): 11017–20. http://dx.doi.org/10.1039/c9cc05413h.

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K. Patil, Meghshyam, Avvari N. Prasad, and Benjaram M. Reddy. "Zirconia-Based Solid Acids: Green and Heterogeneous Catalysts for Organic Synthesis." Current Organic Chemistry 15, no. 23 (December 1, 2011): 3961–85. http://dx.doi.org/10.2174/138527211798072430.

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Yang, Su, Xiaoxuan Guo, Xiaomei Pan, Liuyu Gu, Xueping Liu, Lijing Gao, and Guomin Xiao. "Synthesis of Brominated Alkanes via Heterogeneous Catalytic Distillation over Al2O3/SO42−/ZrO2." Catalysts 11, no. 12 (November 30, 2021): 1464. http://dx.doi.org/10.3390/catal11121464.

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Concentrated sulfuric acid is generally used as a catalyst for producing brominated alkanes in traditional methods, but is highly corrosive and difficult to separate. This work reports the preparation of bromopropane from n-propanol based on a reactive distillation strategy combined with alumina-modified sulfated zirconia (Al2O3/SO42−/ZrO2) as a heterogenous catalyst. As expected, under the optimum reaction conditions (110 °C), the yield of bromopropane was 96.18% without side reactions due to the reactive distillation strategy. Meanwhile, the microscopic morphology and performance of Al2O3/SO42−/ZrO2 were evaluated by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Brunner–Emmet–Teller (BET), Fourier transform infrared spectroscopy (FT–IR), and other characterization methods. The results confirmed that the morphology of zirconia sulfate is effectively regulated by the modification method of alumina, and more edges and angles provide more catalytic acid sites for the reaction. Furthermore, Al2O3/SO42−/ZrO2 exhibited high stability and remarkable reusability due to the strong chemical bond Zr–Al–Zr. This work provides a practical method for the preparation of bromopropane and can be further extended to the preparation of other bromoalkanes.

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Pandey, Rajesh K., Anis N. Deshmukh, and Pradeep Kumar. "Synthesis of β‐Keto Esters Promoted by Yttria‐Zirconia Based Lewis Acid Catalyst." Synthetic Communications 34, no. 6 (December 31, 2004): 1117–23. http://dx.doi.org/10.1081/scc-120028644.

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Kumar, Pradeep, Rajesh Kumar Pandey, Mandar S. Bodas, and Mohan K. Dongare. "Yttria-Zirconia Based Lewis Acid: An Efficient and Chemoselective Catalyst for Acylation Reactions." Synlett 2001, no. 02 (December 31, 2001): 0206–9. http://dx.doi.org/10.1055/s-2001-10778.

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Patil, Meghshyam K., Avvari N. Prasad, and Benjaram M. Reddy. "ChemInform Abstract: Zirconia-based Solid Acids: Green and Heterogeneous Catalysts for Organic Synthesis." ChemInform 43, no. 12 (February 23, 2012): no. http://dx.doi.org/10.1002/chin.201212212.

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Kumar, Pradeep, Rajesh Kumar Pandey, Mandar S. Bodas, and Mohan K. Dongare. "ChemInform Abstract: Yttria-Zirconia Based Lewis Acid: An Efficient and Chemoselective Catalyst for Acylation Reactions." ChemInform 32, no. 22 (May 26, 2010): no. http://dx.doi.org/10.1002/chin.200122054.

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Piovano, Federico A., Soledad G. Aspromonte, Carina V. Bergamini, Paula Giménez, and Alicia V. Boix. "CATALYTIC HYDROTHERMAL CONVERSION OF BIO-DERIVED SUGARS FOR LACTIC ACID PRODUCTION USING SOL-GEL SYNTHESIZED ZIRCONIA." Latin American Applied Research - An international journal 53, no. 1 (January 1, 2023): 1–6. http://dx.doi.org/10.52292/j.laar.2023.1145.

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The hydrothermal conversion of a multiple sugars solution (xylose, arabinose and glucose) was studied using high surface ZrO2-based catalysts to produce lactic acid. The catalysts were synthesized by template-assisted sol-gel method and alternative template removal procedures. Samples obtained by template extraction with solvent reported a specific surface area of 323 m2/g, a pore volume of 0.21 cm3/g and a total amount of acid sites of 359 µmol/g. An experimental design was performed to model lactic acid and by-products obtaining around the selected catalyst. The response surface methodology (RSM) was used to optimize the main operating conditions. A mass selectivity of 35.1 % towards lactic acid was found at 183 °C and 212 min. In addition, the reaction mechanisms involved were proposed based on intermediates and degradation compounds detected by HPLC analysis.

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PALS, G. C. G., A. KESHAVARAJA, K. SARAVANAN, and P. KUMAR. "ChemInform Abstract: Efficient Synthesis of Acetals Promoted by a Yttria-Zirconia Based Strong Lewis Acid Catalyst." ChemInform 28, no. 3 (August 25, 2010): no. http://dx.doi.org/10.1002/chin.199703195.

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Pandey, Rajesh K., Sharda P. Dagade, Rajesh K. Upadhyay, Mohan K. Dongare, and Pradeep Kumar. "A facile procedure for tert-butoxycarbonylation of amines promoted by yttria-zirconia based strong Lewis acid catalyst." Arkivoc 2002, no. 7 (June 18, 2002): 28–33. http://dx.doi.org/10.3998/ark.5550190.0003.704.

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Ramalingam, S., and Pradeep Kumar. "Multi-component carbon–carbon bond forming Mannich reaction catalyzed by yttria–zirconia based Lewis acid." Catalysis Communications 9, no. 14 (August 2008): 2445–48. http://dx.doi.org/10.1016/j.catcom.2008.06.011.

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Kumar, Pradeep, and Rajesh Kumar Pandey. "A Facile and Selective Procedure for Transesterification of β-Keto Esters Promoted by Yttria-Zirconia Based Lewis Acid Catalyst." Synlett 2000, no. 2 (February 2000): 251–53. http://dx.doi.org/10.1055/s-2000-6496.

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Barton, David G., Stuart L. Soled, George D. Meitzner, Gustavo A. Fuentes, and Enrique Iglesia. "Structural and Catalytic Characterization of Solid Acids Based on Zirconia Modified by Tungsten Oxide." Journal of Catalysis 181, no. 1 (January 1999): 57–72. http://dx.doi.org/10.1006/jcat.1998.2269.

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Shyamsundar, M., and SZM Shamshuddin. "Effective synthesis of n-butyl salicylate over wash coated cordierite honeycomb by zirconia and its mixed oxides: a kinetic study." Bangladesh Journal of Scientific and Industrial Research 53, no. 1 (March 11, 2018): 63–76. http://dx.doi.org/10.3329/bjsir.v53i1.35912.

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Cordierite honeycombs were coated with solid acid catalysts such as ZrO2 (Z), Mo(VI)/ZrO2 (MZ) and Pt-SO4 2-/ZrO2 (PSZ) were prepared and characterized for their physico-chemical properties. These catalytic materials were characterized for their total surface acidity, crystallinity, functionality, elemental analysis and morphology by using techniques such as NH3 -TPD, PXRD, FTIR, ICP-OES, SEM and TEM respectively. These honeycomb catalysts were used for the liquid phase transesterification reaction of methyl salicylate (MS) with n-butanol (n-BA). Optimization of reaction conditions such as reaction temperature, reaction time, amount of catalysts and molar ratio of the reactants were carried out to obtain maximum yield of transester (n-butyl salicylate). n-butyl salicylate is obtained as major product and di-butyl ether is obtained as minor product. Highest total transester 70 % obtained by MZ and 80 % n-butyl salicylate and 10 % selectivity of di-butyl ether obtained in the presence of 0.4 g of honeycomb coated catalysts at a molar ratio of MS: n-BA 2:1, reaction temperature 403 K and reaction time 4 h. The energy of activation (16.81 and 14.92 kJ mol-1) and temperature coefficient (1.36 and 1.12) values of the MZ and PSZ were obtained from the kinetic studies. Pre-adsorption studies showed that the transesterification reaction methyl salicylate with n-butyl alcohol over honeycomb catalysts follows Langmuir-Hinshelwood mechanism. A reaction mechanism for transesterification is proposed based on the kinetic data. Reactivation and reusability studies of the honeycomb coated as well as powder form of catalysts up to 6 reaction cycles were also studied.Bangladesh J. Sci. Ind. Res.53(1), 63-76, 2018

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Ramalingam, S., and Pradeep Kumar. "Yttria-Zirconia–Based Lewis Acid Catalysis of the Biginelli Reaction: An Efficient One-Pot Synthesis of 3,4-Dihydropyrimidin-2-(1H)-ones." Synthetic Communications 39, no. 7 (March 4, 2009): 1299–309. http://dx.doi.org/10.1080/00397910802519174.

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Kumar, Pradeep, and Rajesh Kumar Pandey. "ChemInform Abstract: A Facile and Selective Procedure for Transesterification of β-Keto Esters Promoted by Yttria-Zirconia Based Lewis Acid Catalyst." ChemInform 31, no. 20 (June 8, 2010): no. http://dx.doi.org/10.1002/chin.200020070.

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