Article
Chemistry, Applied
Vahide Nuran Mutlu, Selahattin Yilmaz
Summary: The glycosidation of glucose with n-butanol was studied using sulphated Zr and tungstophosphoric acid incorporated SBA-15 catalysts, showing improved acidity and higher yields of butyl glucoside. The TPA-SBA-15 catalyst demonstrated the highest activity and selectivity, with stable and reusable performance. Further studies on reaction temperature and catalyst amount were conducted to optimize the reaction parameters.
Article
Chemistry, Organic
Yangwu Tian, Xiaqun Guo, Meichao Li, Chunmei Li, Xinquan Hu, Liqun Jin, Nan Sun, Baoxiang Hu, Zhenlu Shen
Summary: In this research, a novel catalyst 1-Me-AZADO was designed and immobilized on SBA-15 support, showing high catalytic efficiency for selective oxidation of alcohols to carbonyl compounds under Anelli's conditions. Moreover, this immobilized catalyst can be conveniently recovered and reused multiple times without significant loss of catalytic activity.
Article
Chemistry, Physical
Xiaolu Chen, Jing Wang, Yue Yu, Hong Chen, Xiao Wu, Shuang Gao
Summary: In this study, the transition metal iron substituted polyoxometalates cluster was immobilized on NH2 functionalized SBA-15, resulting in PMo11Fe/SBA composite materials with improved catalytic activities and recyclability.
Article
Chemistry, Applied
Wenlan Cai, Xiaoyan Ni, Fanyong Meng, Lin Sun, Runwei Wang, Sen Lin
Summary: The acid-free synthesis of Ga-containing SBA-15 mesoporous materials allows for tuning their morphological and acidic properties. Ga-SBA-15 exhibits high acid amount and adjustable morphology due to the presence of dispersed bending particles. The improved interparticle-type mesoporosity of Ga-SBA-15 provides highly accessible active sites for large molecules. Ga-SBA-15 also shows a shift from Bro center dot nsted-type acidity to Lewis-type acidity.
MICROPOROUS AND MESOPOROUS MATERIALS
(2022)
Article
Chemistry, Applied
Edgar Tututi-Rios, Horacio Gonzalez, Denis A. Cabrera-Munguia, Aida Gutierrez-Alejandre, Jose L. Rico
Summary: Through the sol-gel method, Sn-SBA-15 catalysts modified with -PrSO3H groups were synthesized, which significantly improved the acid properties of the catalysts and increased the conversion rate of the esterification reaction between oleic acid and methanol.
Article
Chemistry, Physical
Castelo Bandane Vilanculo, Marcio Jose da Silva
Summary: This study investigated the catalytic activity of different acids in epoxidation reactions of terpene alcohols, with H3PMo12O40 showing the highest activity and selectivity towards nerol epoxide. The results suggest that Molybdenum and protons in H3PMo12O40 are the main active sites in this reaction.
MOLECULAR CATALYSIS
(2021)
Article
Chemistry, Physical
Shuxin Mao, Svenja Budweg, Anke Spannenberg, Xiaodong Wen, Yong Yang, Yong-Wang Li, Kathrin Junge, Matthias Beller
Summary: The combination of Fe(OTf)(2) with N-methyl bis(picolylamine) (Me-bpa) L7 enables the epoxidation of linear olefins, including terminal, internal, and cyclic ones, using hydrogen peroxide as a terminal oxidant under mild conditions. Improved yields of epoxides up to 75% have been achieved in the presence of picolinic acid as an additive.
Article
Chemistry, Physical
G. Dhinagaran, S. Prashanna Suvaitha, M. Muthukumaran, K. Venkatachalam
Summary: The chemoselective catalytic oxidation of olefin derivatives containing alcoholic and olefinic groups using Co-Salen immobilized on SBA-15 was studied. The catalyst showed high selectivity and efficiency in the oxidation reactions, proving its applicability for selective oxidation of olefin derivatives. The conversion and selectivity remained stable over multiple cycles, indicating the stability of the catalyst for potential use in selective oxidation of multifunctional olefin derivatives.
Article
Chemistry, Physical
Dianwen Hu, Xiaojing Song, Hao Zhang, Xinyu Chang, Chen Zhao, Mingjun Jia
Summary: Catalytic epoxidation of styrene with molecular oxygen using transition metal monosubstituted heteropolyacid compounds encapsulated in UiO-66 frameworks shows high catalytic activity and selectivity, with Co-HPA@UiO-66 exhibiting the best performance under mild conditions. The hybrid composite catalyst efficiently converts styrene derivatives to epoxides through the activation of in-situ generated acylperoxy radical intermediate.
MOLECULAR CATALYSIS
(2021)
Article
Polymer Science
Mei-Mei Yang, Hui-Ling Su, De-Hang Yang, Zhi-Yong Chen, Li -Ping Wang, Guang Li
Summary: The aminoated SBA-15 (SBA-15-NH2) was obtained by condensing the hydroxyl group on the surface of SBA-15 with the ethoxy group of 3-aminopropyl triethoxysilane (KH550) coupling agent. Two types of SBA-15-based catalysts (SBA-15-Flu and SBA-15-RB) were then created by loading fluorescein acyl chloride (Flu-Cl) or rhodamine B acyl chloride (RB-Cl) onto the SBA-15 surface. These catalysts were used in the metal-free ATRP of methyl methacrylate (MMA) under 365 nm UV light. The structure of the catalysts was confirmed using various spectroscopy techniques, and their catalytic performance was evaluated through polymerization experiments.
EUROPEAN POLYMER JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Yuanzheng Huang, Ying Jia, Ruomeng Hou, Zhiyong Huang, Keke Shen, Guofeng Jin, Li'an Hou
Summary: TiO2/SBA-15 nanocomposites were synthesized via an in situ hydrothermal method and utilized for VUV photocatalytic degradation of UDMH, showing higher efficiency compared to UV photocatalysis. The optimized TS-2 catalyst exhibited superior photocatalytic activity and reusability under VUV light.
Article
Biochemistry & Molecular Biology
Marcin Kujbida, Agnieszka Wroblewska, Grzegorz Lewandowski, Piotr Miadlicki, Beata Michalkiewicz
Summary: The study compared the activity of W-SBA-15 catalyst to Ti-SBA-15 catalyst in the epoxidation of 1,5,9-cyclododecatriene (CDT). It was found that W-SBA-15 catalyst was 20 times more active than Ti-SBA-15 catalyst. The highest CDT conversion achieved was 86 mol% after a 4-hour epoxidation process. Using the semi-batch method did not significantly improve the value functions of the process, but a faster H2O2 dosing rate resulted in a 9 mol% higher CDT conversion compared to the batch method.
Article
Biochemistry & Molecular Biology
Jose Castanheiro
Summary: Camphene was hydtated over SBA-15 supported with sulfonic acid and tungstophosphoric acid. Isoborneol was the main product, with camphene hydrate and borneol as byproducts. The catalytic activity increased with the amount of tungstophosforic acid immobilized until reaching a maximum, but decreased with further increase. The catalytic stability of PW4-SBA-15-SO3H was observed during consecutive batch runs.
Article
Agricultural Engineering
Oscar Oyola-Rivera, Jiayue He, George W. Huber, James A. Dumesic, Nelson Cardona-Martinez
Summary: This study investigated the catalytic conversion of cellulose to levoglucosenone (LGO) using a combination of dilute sulfuric acid and propylsulfonic acid functionalized SBA-15 (PS-SBA-15) in tetrahydrofuran (THF). The addition of small amounts of liquid acid catalyst such as sulfuric acid was found to complement the use of solid acid catalyst for cellulose conversion, leading to an increase in LGO yield. The main role of the solid Bronsted acid catalyst was to dehydrate the generated levoglucosan (LGA) into LGO, demonstrating a more environmentally friendly approach for LGO production.
BIOMASS & BIOENERGY
(2022)
Article
Chemistry, Physical
Joanna Wisniewska, Izabela Sobczak, Maria Ziolek
Summary: This study investigated the effects of calcium and niobium on the activity of gold catalysts in methanol oxidation under different conditions. It was found that the presence of calcium and niobium had a synergistic effect on the activity of the gold catalyst, while niobium directed the selectivity of the reaction. The oxidation states and concentration of catalyst components remained unchanged during the methanol oxidation reaction.
CATALYSIS SCIENCE & TECHNOLOGY
(2021)
Article
Chemistry, Applied
Qingyuan Zheng, Jack H. Williams, Scott Elgersma, Mick D. Mantle, Andrew J. Sederman, G. Leendert Bezemer, Constant M. Guedon, Lynn F. Gladden
Summary: In this study, a pilot-scale fixed-bed reactor compatible with NMR/MRI was developed for Fischer-Tropsch synthesis. Multiple magnetic resonance techniques were applied to quantitatively characterize different product species within catalyst pellets, providing valuable information for catalyst and reactor optimization.
Article
Chemistry, Applied
Lisa Ramisch, Sebastian Pfaff, Sabrina M. Gericke, Edvin Lundgren, Johan Zetterberg
Summary: We present a combination of optical operando techniques that allow simultaneous measurement of adsorbed species on catalyst surfaces, monitoring of surface oxide formation, and imaging of the gas phase above the catalyst surface. The experimental setup was validated by studying CO oxidation on Pd(100) at different pressures, revealing the effects of pressure on the heterogeneous catalytic reaction.
Article
Chemistry, Applied
Marta Paniagua, Gabriel Morales, Juan A. Melero, Daniel Garcia-Salgado
Summary: The influence of common impurities in levulinic acid on the catalytic performance of different acid catalysts for bio-jet fuel production was studied. It was found that furfural had the greatest detrimental effect on catalyst performance, while propyl-sulfonic acid-modified SBA-15 and sulfonic acid resin Amberlyst-70 showed good regeneration ability.
Article
Chemistry, Applied
Jesus Tapiador, Pedro Leo, Guillermo Calleja, Gisela Orcajo
Summary: This study presents a new MOF material, Zn-URJC-13, with acid and basic sites, permanent porosity, and high affinity to CO2 molecules. The Zn-URJC-13 catalyst exhibits efficient performance in CO2 cycloaddition reactions and can be reused multiple times.
Article
Chemistry, Applied
Dan Zhao, Vita A. Kondratenko, Dmitry E. Doronkin, Shanlei Han, Jan-Dierk Grunwaldt, Uwe Rodemerck, David Linke, Evgenii V. Kondratenko
Summary: This study demonstrates the potential of cheap and commercially available Zr or Ti-based supports and ZnO to serve as active and selective catalysts for propane dehydrogenation (PDH). The catalytically active species formed in situ under PDH conditions consist of isolated ZnOx. ZnOx on the surface of LaZrOx shows the highest rate of propene formation.
Article
Chemistry, Applied
Hanbyeol Kim, Jung Rae Kim, Young-Kwon Park, Jeong-Myeong Ha, Jungho Jae
Summary: In this study, metal phosphates were used as catalysts for biomass conversion to produce sustainable aromatics through DielsAlder cycloaddition reactions. The effects of synthesis method, activation method, and P/Ti molar ratio on the structure and acid properties of titanium phosphate catalysts were systematically studied. The mesoporous titanium phosphate catalyst synthesized by hydrothermal method at 180℃ for 12 h followed by ethanol refluxing at 60℃ for 24 h at a molar P/Ti ratio of 1 showed the highest surface area and acid site density.
Article
Chemistry, Applied
Yasin Khani, Sumin Pyo, Kwang-Eun Jeong, Chul-Ung Kim, Moonis Ali Khan, Byong-Hun Jeon, Kun-Yi Andrew Lin, Siyoung Q. Choi, Young-Kwon Park
Summary: A protonated form of Zeolite Socony Mobil-5 (H-ZSM-5) catalyst was synthesized through a hydrothermal method using different sources of silica. The effect of loading the catalyst with yttrium, samarium, and gadolinium on the acidic properties was investigated. Among the metal-loaded catalysts, the Sm/LHZ catalyst showed the best performance in the methanol to propylene conversion due to its high amount of weak and intermediate acid sites, while the Gd-LHZ catalyst increased the selectivity towards ethane and propane.
Article
Chemistry, Applied
Michael Franc, Ivana Cisarova, Jan Vesely
Summary: The present study investigates an enantioselective cyclization of enals with imidazolone derivatives catalyzed by a combination of achiral Pd(0) complex and chiral secondary amine. Corresponding spirocyclic imidazolones were produced in high yields with moderate diastereoselectivity and excellent enantioselectivity. The developed co-operative catalytic methodology provides a highly substituted spirocyclic scaffold with four stereogenic centers under mild conditions.
Article
Chemistry, Applied
Mauro Alvarez, Jennifer Cueto, David P. Serrano, Pablo Marin, Salvador Ordonez
Summary: This study focuses on improving the formulation and preparation methods of catalysts for the production of dimethyl carbonate. By using suitable catalyst preparation methods and copper salt precursors, the researchers successfully produced catalysts with optimal performance for dimethyl carbonate formation.
Article
Chemistry, Applied
Claudia J. Keijzer, Luc C. J. Smulders, Dennie Wezendonk, Jan Willem de Rijk, Petra E. de Jongh
Summary: This study investigates the catalytic behavior of alpha-alumina supported silver catalysts in the presence of chloride. It is found that the particle size of silver can affect the selectivity of the catalyst, but different strategies lead to different results. In this size range, the selectivity of ethylene oxide is correlated to the Ag : Al2O3 surface ratio.
Article
Chemistry, Applied
Takeshi Aihara, Wataru Aoki, Michikazu Hara, Keigo Kamata
Summary: The development of acid-base bifunctional catalysts is important for promoting specific chemical transformations. In this study, Ti-based perovskite oxides were synthesized and used as catalysts for two C-C bond-forming reactions (cyanosilylation and Knoevenagel condensation). The highly pure SrTiO3 nanoparticles with a high specific surface area exhibited the highest catalytic performance, and could be easily recovered and reused.
Article
Chemistry, Applied
Olga Gorlova, Petra Pribylova, Eliska Vyskocilova, Katerina Peroutkova, Jan Kohout, Iva Paterova
Summary: This study investigates the Baeyer-Villiger oxidation of beta-cyclocitral using tin-modified mixed oxides as catalysts. The optimal reaction conditions and the effects of various factors on the reaction course and selectivity were determined. The results show that tin-modified mixed oxides exhibit high activity and selectivity in the oxidation reaction.
Article
Chemistry, Applied
M. I. Avila, M. M. Alonso-Doncel, L. Briones, G. Gomez-Pozuelo, J. M. Escola, D. P. Serrano, A. Peral, J. A. Botas
Summary: The catalytic fast pyrolysis of lignin using ion-exchanged zeolite catalysts showed significant improvements in bio-oil quality and the production of aromatic hydrocarbons and oxygenated compounds.
Article
Chemistry, Applied
Enrico Catizzone, Giorgia Ferrarelli, Paolo Bruno, Girolamo Giordano, Massimo Migliori
Summary: The acid-catalysed alcohol conversion reaction is a promising route for de-fossilization strategies. Research on pure alcohol conversion and simultaneous dehydration of mixed alcohols have shown different product compositions, with the type and distribution of acid sites affecting the reaction mechanism.
Article
Chemistry, Applied
Alireza Ranjbari, Juho Kim, Jihee Yu, Jiyun Kim, Mireu Park, Nayoung Kim, Kristof Demeestere, Philippe M. Heynderickx
Summary: This study investigated a novel kinetic model for the adsorption and photocatalytic degradation of methyl orange using commercial ZnO and reduced ZnO photocatalysts. The results provided new insights into the interaction of catalysts with molecules of different charges and compared with a previous study on methylene blue. The presence of oxygen vacancies in ZnO and their effects on adsorption and photocatalytic degradation were analyzed, and the photocatalytic degradation rate of reduced ZnO was found to increase significantly.