Article
Chemistry, Multidisciplinary
Diego D. Perera-Solis, Vladimir L. Zholobenko, Andrew Whiting, Hugh Christopher Greenwell
Summary: This study investigated the ketonic decarboxylation of dodecanoic acid using MgO as a catalyst, showing that the ketone yield increases with reaction temperature. It was found that temperature is the main factor controlling the reaction yield, rather than surface area or particle size.
Article
Chemistry, Physical
Sasha Yang, Binbin Qian, Yuan Wang, Kenji Taira, Qiaoqiao Zhou, Karen Wilson, Adam F. Lee, Lian Zhang
Summary: In this study, the reductive thermal processing of iron oxide catalyst derived from fly ash waste was investigated. The resulting catalyst showed enhanced activity for the ketonization reaction of acetic acid due to the introduction of surface oxygen vacancies and acid-base sites.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Engineering, Chemical
Jacob H. Miller, Glenn R. Hafenstine, Hannah H. Nguyen, Derek R. Vardon
Summary: This study presents a kinetic study of ketonization of carboxylic acids (VFAs) and validates the derived kinetic parameters in a reactor simulation. The results indicate that the ketonization rate is positively correlated with acid pressure at low pressures, transitioning to zero order at higher pressures. Additionally, the presence of ketonization coproduct water inhibits the reaction rate, but ketones or CO2 do not.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Biotechnology & Applied Microbiology
Gheorghita Mitran, Shaojiang Chen, Wenyu Huang, Dong-Kyun Seo
Summary: La-based zeolites have been studied for acetic acid conversion, with Bronsted acid sites promoting cyclohexyl acetate and acetone selectivity, while Lewis acidity favors acetone transformation into isobutene. The sample with the highest Bronsted acidity, La-H-13X, showed the highest activity for both reactions, indicating the importance of Bronsted acidity in the studied reactions.
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
(2021)
Article
Energy & Fuels
Ahmed M. I. Elkhaiary, Bartosz Rozmyslowicz, Jher Hau Yeap, Michael H. Studer, Jeremy S. Luterbacher
Summary: The acetate fraction, a compound found in many plant species, can be easily extracted as acetic acid. This study developed a reaction network for the conversion of acetic acid into cycloalkenes and aromatics suitable for use as an aviation fuel additive. The proposed model and parameters provide insights into the reaction network and optimal operation conditions.
Article
Engineering, Chemical
Sabrina Zaidi, N. Asikin-Mijan, A. S. Hussain, Mohd Sufri Mastuli, Fahad A. Alharthi, Abdulaziz Ali Alghamdi, Y. H. Taufiq-Yap
Summary: Various synthesis methods have been reported for the preparation of lanthanum-modified zirconia (La/ZrO2) catalysts, with deep-deposition-ultrasonication (DPU) and deposition-precipitation (DP) methods yielding smaller particles compared to other methods. The La/ZrO2-DP catalyst exhibited the best performance in ketonization reactions, with high conversion rates and selectivity for fatty acids.
JOURNAL OF THE TAIWAN INSTITUTE OF CHEMICAL ENGINEERS
(2021)
Article
Chemistry, Multidisciplinary
Tejas Goculdas, Siddharth Deshpande, Weiqing Zheng, Raymond J. Gorte, Sunitha Sadula, Dionisios G. Vlachos
Summary: By exploring various alkaline earth metals and mixed metal oxides, we found that MgO achieves a yield of approximately 90% in cross-ketonization reaction by minimizing decarboxylation side reaction. We illustrated the role of molecular structure and complex formation over alkaline-earth metal oxides in reducing side reactions. Catalyst deactivation was overcome by regeneration over multiple runs. This research demonstrates the effectiveness of heterogeneous catalysts for developing renewable surfactants through cross ketonization.
Article
Chemistry, Physical
Bert Boekaerts, Ward Lorenz, Joost Van Aelst, Bert F. Sels
Summary: This study investigated the kinetics of fatty acid ketonization using two different TiO2 catalysts. The results showed that the rutile catalyst, with higher Lewis acid density, had higher activity but was more strongly inhibited by ketone, water, and carbon dioxide compared to anatase. Kinetic models were developed to understand the rate-determining step in the ketonization mechanism, which was found to be the C-C coupling of adsorbed species. The study also found that the substrate chain length, solvent, and liquid phase purging had an impact on the ketonization kinetics, suggesting potential for future improvements.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Chemistry, Physical
Jiao Huang, Liwen Li, Xiaoxia Wu, Yonghua Guo, Zijun Yang, Hua Wang, Qingfeng Ge, Xinli Zhu
Summary: Studying reactions on specific surfaces of metal oxides can provide insights into the structure-activity relationships. Anatase TiO2 with different exposed facets were synthesized and tested for the catalytic ketonization of propionic acid. The results suggest that the surface geometry of the metal oxide plays a crucial role in the reaction, with the (001) facet being the most active.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Fan Lin, Wenda Hu, Nicholas R. Jaegers, Feng Gao, Jian Zhi Hu, Huamin Wang, Yong Wang
Summary: The effects of water on the carboxylic acid ketonization reaction over solid Lewis-acid catalysts were investigated using various analytical techniques. The presence of water vapor in the feed gas was found to decrease the reaction rate by increasing the activation barrier of acetic acid adsorption on anatase TiO2 catalyst. Water was found to associate with the adsorbed intermediates on the catalyst surface and alter their reactivity for the ketonization reaction. The presence of water vapor also affected the species present on the catalyst surface and led to lower ketonization activity.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Engineering, Chemical
Pablo Lozano, Ana I. Simon, Lucia Garcia, Joaquin Ruiz, Miriam Oliva, Jesus Arauzo
Summary: This study investigated the effect of catalyst loading on the Aqueous Phase Reforming of bio-oil aqueous fraction using a specific catalyst. Results showed that increasing catalyst loading led to higher gas production with higher alkanes content. Acetol exhibited the highest reactivity, while the conversion of acetic acid was very low.
Article
Chemistry, Multidisciplinary
Elnaz Jamalzade, Koorosh Kashkooli, Liam Griffin, G. Peter van Walsum, Thomas J. Schwartz
Summary: Biomass has attracted significant attention as a feedstock for producing energy and chemicals as a replacement for crude oil. This study combines chemical and biological processing to produce long-chain ketones with low oxygen content. By converting lignocellulosic biomass into medium-chain-length carboxylic acids and further oligomerizing them using chemical catalysis, the resulting molecules fall within the C10-C20 range and have potential as additives for existing hydrocarbon jet fuels. The study also evaluated various catalysts for the conversion of ethyl esters recovered from fermentation into long-chain ketones, with Pd/CeZrOx proving to be the most active. Additionally, a reaction network involving direct ester ketonization, dehydration, and hydrogenation was proposed based on experimental measurements and thermodynamic calculations.
REACTION CHEMISTRY & ENGINEERING
(2021)
Article
Energy & Fuels
Balaji Sridharan, Homer C. Genuino, Daniela Jardan, Erwin Wilbers, Henk H. van de Bovenkamp, Jozef G. M. Winkelman, Robbie H. Venderbosch, Hero J. Heeres
Summary: The combination of molten salts and pyrolysis is considered a promising route for producing renewable biofuels. By using molten salts to convert woody biomass into liquid hydrocarbon products, researchers have achieved a low oxygen content. The experimental studies showed positive results, indicating the potential of this method.
Article
Materials Science, Ceramics
Wafa Ksila, Mohamed Kadri Younes, Abdelhamid Ghorbel, Alain Rives
Summary: Our research focused on the preparation of new zirconia-doped telluric acid catalysts using the sol-gel method, and investigated the optimization of various preparation parameters on the catalyst. The results showed that the addition of HNO3 significantly improved the acidity of the catalyst, while doping zirconia with telluric acid enhanced both the acidity and catalytic performance of the catalyst. However, calcination of the catalyst led to a loss in acidity and a decrease in catalytic activity.
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
(2021)
Article
Chemistry, Physical
Runze Ma, Christopher R. O'Connor, Gregory Collinge, Sarah I. Allec, Mal-Soon Lee, Zdenek Dohnalek
Summary: The dynamics of acetic acid on anatase TiO2(101) were investigated using scanning tunneling microscopy experiments and density functional theory calculations. The study showed the simultaneous diffusion of bidentate acetate and a bridging hydroxyl, as well as the transient formation of molecular monodentate acetic acid. The diffusion rate was found to be strongly dependent on the position of hydroxyl and adjacent acetate(s). A three-step diffusion process involving acetate and hydroxyl recombination, acetic acid rotation, and acetic acid dissociation was proposed. This study provides insights into the importance of bidentate acetate dynamics in the formation of monodentate species, which drive selective ketonization.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)