Article
Chemistry, Physical
Kihun Nam, Hae Won Ryu, Min Yeong Gim, Do Heui Kim
Summary: This study demonstrates that physically mixed NiO can act as an excellent catalyst promotor for MDA, significantly enhancing the yield and stability by promoting the dispersion of MoCx active sites and suppressing coke formation.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2021)
Article
Energy & Fuels
Mengmeng Huang, Jianpeng Li, Qiang Liu, Meng Zhang, Zhongyi Liu, Beibei Gao
Summary: Hollow HZSM-5 zeolite catalysts with different cavity sizes and tunable shell thickness were prepared and exhibited higher conversion and selectivity in methane dehydroaromatization reaction compared to conventional solid catalyst.
Article
Biochemistry & Molecular Biology
Jing Hu, Yangyang Li, Shujie Wu, Xiaohui Wang, Cai Xia, Xinyu Zhao, Jinglin Liu
Summary: The methane dehydro-aromatization reaction (MDA) is a promising process for methane valorization. However, using zeolite catalysts can lead to rapid deactivation due to coke formation. Controlling the distribution of molybdenum sites on the zeolite surface is crucial for inhibiting coke formation and improving stability. MoO3 nanobelts can be used as alternative precursors to prepare MDA catalysts.
Article
Chemistry, Multidisciplinary
Ning Wang, Xinglong Dong, Lingmei Liu, Dali Cai, Qingpeng Cheng, Jianjian Wang, Yilin Hou, Abdul-Hamid Emwas, Jorge Gascon, Yu Han
Summary: The crystal size of HZSM-5 determines the form and location of MoCx species; MoCx sites are preferentially deactivated on nano-sized HZSM-5; Properly protecting MoCx particles can enhance their activity.
CELL REPORTS PHYSICAL SCIENCE
(2021)
Article
Engineering, Chemical
Xinzhuang Zhang, Yunda Han, Dapeng Li, Zhanguo Zhang, Xiaoxun Ma
Summary: This study investigated the attrition behavior of a Mo/HZSM-5 catalyst in non-oxidative aromatization of methane under different temperatures, running times, and process conditions. Carbon deposition on the catalyst was found to enhance its attrition resistance at high temperatures. The attrition of catalyst particles and carbon deposits were found to have an impact on catalytic performance.
CHINESE JOURNAL OF CHEMICAL ENGINEERING
(2021)
Article
Chemistry, Multidisciplinary
Maria Teresa Portilla, Francisco J. Llopis, Manuel Moliner, Cristina Martinez
Summary: Methane aromatization is an interesting technology with potential, but faces limitations due to thermodynamics and catalyst properties. Mo/H-ZSM-5 is a widely studied catalyst for this process.
APPLIED SCIENCES-BASEL
(2021)
Article
Energy & Fuels
Yong Hyun Lim, Hae Won Ryu, Kihun Nam, Yeseul Hwang, Jangeon Roh, Do Heui Kim
Summary: The direct non-oxidative aromatization of shale gas is a promising technique for utilizing abundant gas resources without traditional energy-intensive gas fractionation processes. However, the separate precarburization process required to activate catalysts hinders the practical application of this technique. In this study, shale gas was investigated as a precarburizing feed to unify the precarburizing gas and main reactant. The use of shale gas reduced the precarburization time and enhanced the catalytic performance, with the precarburization temperature playing a significant role.
Article
Chemistry, Physical
Heidy Ramirez-Mendoza, Mafalda Valdez Lancinha Pereira, Tom Van Gerven, Cecile Lutz, Ignacio Julian
Summary: This study explored the use of ultrasound-assisted ion-exchange technique to enhance the dispersion of molybdenum in Mo/ZSM-5 catalyst, improving its fixation on the zeolite framework. Despite the improved metal dispersion, the catalytic activity did not significantly increase compared to the traditional method.
Article
Chemistry, Multidisciplinary
Jing Hu, Chunxue Yang, Dawei Wang, Bing Liu, Qingxu Guan, Peijun Dong, Shengyan Wang, Jinglin Liu
Summary: In this study, a Mo-based MCM-49 catalyst was successfully prepared using a citric acid-ammonium molybdate co-impregnation method to improve the dispersion of metallic Mo. Through a series of characterization results, it was found that the introduction of citric acid changed the coordination state of Mo and improved the catalytic activity by affecting the distribution of active sites. The experimental results showed that the catalyst prepared under specific conditions exhibited high methane conversion and aromatics yield, and demonstrated good catalytic stability.
Article
Materials Science, Multidisciplinary
Nagaraju Pasupulety, Abdurrahim A. Al-Zahrani, Mohammad A. Daous, Hafedh Driss, Lachezar A. Petrov
Summary: In this study, the influence of second metals (M = Ce or Pd or Nb) on Mo2C active phase reduction and surface MoOx species transformation in M-Mo2C/HZSM-5 catalysts for methane dehydroaromatization was investigated. It was found that Pd-Mo2C/HZSM-5 catalyst showed the highest benzene yield due to limited Mo2C active phase reduction and promoted coke burning, while Ce-Mo2C/HZSM-5 catalyst exhibited decreased methane conversion. Additionally, Nb-Mo2C/HZSM-5 catalyst produced superior coke via CH4 decomposition, resulting in a lower benzene yield compared to Pd-Mo2C/HZSM-5 and Mo2C/HZSM-5 catalysts after 10 hours of reaction at 700 degrees C.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Chemistry, Physical
Ming Cheng, Hugo Cruchade, Ludovic Pinard, Eddy Dib, Honghai Liu, Jiujiang Wang, Xinmei Liu, Zi-Feng Yan, Zhengxing Qin, Svetlana Mintova
Summary: Molybdenum-modified HZSM-5 catalysts are widely used for methane dehydroaromatization but suffer from rapid deactivation due to coke formation. This study proposes a new synthesis approach to improve the performance and stability of the catalysts by removing the crystal core. The results show that removing the crystal core effectively mitigates catalyst deactivation by relocating the coke from micropores to macropores, and the alkaline treatment further enhances the catalyst properties.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Chemistry, Physical
Angeles Lopez-Martin, Alfonso Caballero, Gerardo Colon
Summary: The reduction temperature has a crucial effect on the catalytic performance of Mo/HZSM-5 catalyst for methane dehydroaromatiztion reaction. The optimum performance is achieved at 550 degrees C, which may be attributed to the higher fraction of reduced Mo species.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Review
Chemistry, Applied
Dongyang Liu, Liyuan Cao, Guohao Zhang, Liang Zhao, Jinsen Gao, Chunming Xu
Summary: This paper reviews the research progress of aromatization for light alkanes on HZSM-5 zeolites and its metal-containing catalysts, focusing on the introduction of metal species and dehydrogenation mechanisms to enhance the selectivity of BTX. The interaction of Zn or Ga with HZSM-5 zeolite forms Lewis acid sites, promoting the dehydrogenation of alkanes and intermediate products to increase BTX selectivity.
FUEL PROCESSING TECHNOLOGY
(2021)
Article
Chemistry, Applied
Xianliang Meng, Mingzhi Dai, Yang Zhou, Jiaxin Wu, Pengcheng Li, Bangming Yang, Ruizhi Chu, Xiao Li, Weisong Li, Guoguang Wu, Chenxiao Wang
Summary: In order to improve the performance and stability of catalytic methanol aromatization, a Zn-modified HZSM-5/SAPO34 composite molecular sieve was synthesized using hydrothermal synthesis. The introduction of in-situ Zn changed the morphology of the molecular sieve, leading to a polycrystalline stacked bloom-like structure and abundant micro-pore channels. The introduction of secondary external Zn increased the amount of weak strong acidic sites and improved the BTX selectivity.
MICROPOROUS AND MESOPOROUS MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Bing Zhu, Haibo Li, Xue Wang, Subing Fan, Junmin Lv, Tian-sheng Zhao
Summary: The [Zn,Mo]/HZ-5 catalysts were prepared using the impregnation method, and the effect of Mo content on catalytic performance was investigated. The catalysts were characterized by various techniques, and it was found that coaromatization process had higher aromatics yield and better stability. The modification with Mo species regulated the acidity of Zn/HZ-5 and increased the amount of Zn(OH)(+) species, resulting in improved dehydroaromatization ability and higher aromatics yield. The carbon deposit and deactivation behaviors were also studied, and under the optimized conditions of 470°C and WHSV = 1.0 h(-1), the BTEX yield reached a maximum of 64.0%.
REACTION CHEMISTRY & ENGINEERING
(2023)
Article
Chemistry, Physical
Ming-Yi Chen, Ngoc Thanh Thuy Tran, Ahmed Abubakar Alao, Wen-Dung Hsu
Summary: This study demonstrates the significance of surface Pt atom arrangement for the efficiency of ORR in PEMFCs and reveals the correlation between Pt-Pt average distance and O2 dissociation barrier. Furthermore, the study discovers a robust correlation between the level of the catalyst's d-band center and O2 adsorption energy. High-entropy alloy substrates provide potential for controlling Pt arrangement and O2 dissociation barrier.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Eduardo C. Atayde Jr, Babasaheb M. Matsagar, Yu-Cheng Wang, Kevin C. -W. Wu
Summary: This study presents the first application of an acidic MOF, Sulfated MOF-808, in catalyzing the HAA reactions of furan oligomers for the production of biofuel precursors. The catalyst showed high yield, selectivity, and recyclability, making it versatile for different starting materials.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Maria do Carmo Rangel, Francieli Martins Mayer, Soraia Jesus de Oliveira, Sergio Gustavo Marchetti, Fabricio Luiz Faita, Doris Ruiz, Giovanni Saboia, Mariana Kieling Dagostini, Jonder Morais, Maria do Carmo Martins Alves
Summary: This study developed a new catalyst by investigating the effect of magnesium on the catalytic properties of hematite in ethylbenzene dehydrogenation. The catalyst showed important differences in activity, selectivity, and stability, making it a promising candidate for commercial applications.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Yanjun Li, Qian Wang, Hui Tian, Mingyuan Zhu, Yuanyuan Liu
Summary: A novel strategy using microwave-assisted precipitation was proposed to prepare defective CsH3PMo11VO40 catalyst for the oxidation of methacrolein to methacrylic acid. Microwave treatment accelerates crystallization, increases vanadyl species content, and forms defective Keggin structures, thereby enhancing the oxidation capacity of the catalyst.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Rajeshwari Athavale, Sailee Gardi, Fatima Choudhary, Dayanand Patil, Nandkishor Chandan, Paresh More
Summary: In this study, a novel acidic ionic liquid catalyst was prepared and used for the synthesis of bis-indolyl methane derivatives. The catalyst exhibited short reaction times, easy purification, and reusability.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Masatomo Hattori, Takato Hattori, Masakuni Ozawa
Summary: Cu-added gamma-Al2O3 catalysts were prepared with varying Cu loadings and the effects of copper oxidation states on catalytic activity were investigated. The results showed that the addition of copper increased the catalyst activity, but excessive copper loading decreased catalytic activity. XRD and TEM analysis indicated the formation of a solid solution of copper oxide species on the surface of gamma-Al2O3. XAS and TPR data demonstrated variations in copper oxidation states among the catalysts.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Liwei Fang, Shiyang Niu, Shengsen Wang, Yiqing Lu, Yuanhui Cheng
Summary: In this study, PtNi alloy on nitrogen-doped carbon and SnO2 dual-support was designed to modulate the metal-support interaction, resulting in improved catalytic activity and stability for oxygen reduction reaction. The SnO2/PtNi/NC catalyst exhibited a strongly coupled interface, enhanced electron transfer, and higher half-wave potential compared to PtNi/NC and commercial Pt/C.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Shohei Harada, Duanxing Li, Kenta Iyoki, Masaru Ogura
Summary: This study investigates the catalytic performance of a composite catalyst composed of ZnZrOX and H-zeolite for the hydrogenation of CO2. The deactivation of the composite catalyst is influenced by ion exchange of Zn2+ and/or coke, with their effects differing based on the zeolite structure. Separating the grains of the composite catalyst can prevent deactivation.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Laura Proano, Christopher W. Jones
Summary: In this study, NiGa alloy particles supported on CeO2, ZrO2, and ZrO2-CeO2 solid solutions were prepared and characterized. The nature of the support was found to have a significant influence on the catalyst's activity and selectivity, with the crystalline structure of ZrO2 having the greatest impact. Pure ZrO2 showed the highest methanol selectivity and CO2 conversion at high Zr:Ce ratios. In equimolar and Ce-rich conditions, basic sites and oxygen vacancies were found to be the key parameters affecting methanol production.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Liyan Zhang, Yinze Yang, Leilei Zhou, Fengyu Zhao, Haiyang Cheng
Summary: 1,6-Hexamethylenediamine was successfully synthesized via the reductive amination of 1,6-hexanediol using a Ru/PRL(x)-Al2O3 catalyst. The highly dispersed and anchored Ru species, formed by 1,10-phenanthroline (PRL), played a crucial role in the catalytic reaction. The formation of new acid-base pairs, electron deficient Ru species, and smaller nanoparticles contributed to the improved catalytic performances of the Ru/PRL-Al2O3 catalyst.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Anita Horvath, Miklos Nemeth, Andrea Beck, Gyorgy Safran, Valeria La Parola, Leonarda Francesca Liotta, Gregor Zerjav, Matevz Roskaric, Albin Pintar
Summary: This study investigates the catalytic and structural changes caused by the addition of 0.25 wt% indium in a 3% Ni/CeO2-Al2O3 catalyst prepared by impregnation method. The results show that the addition of indium can decrease the activity of the catalyst, but it improves its stability and reduces coking.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Ankush Kularkar, Vaibhav Vilas Khedekar, Sachin D. Chaudhari, Mudavath Ravi, Sadhana S. Rayalu, Penumaka Nagababu
Summary: Efficiently addressing the challenges of photocatalytic CO2 reduction to CH3OH is crucial. This study developed Zn-BTC MOF and its composites with CaIn2S4, achieving highly efficient and robust photocatalytic CO2 reduction to CH3OH under ambient conditions, using H2O2 as the hydrogen source. Among the composites, ZMCIS4 demonstrated excellent performance with a CH3OH evolution of 49100 μmol/g.cat and a quantum efficiency of approximately 78.41%. The enhanced performance was attributed to the production of nascent hydrogen atoms (H center dot) through the photo-splitting of H2O2 on the ZMCIS surface.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Dan Liu, Yudong Li, Chengyu Wang, Haiyue Yang, Rong Wang, Shujun Li, Xiaohui Yang
Summary: In this study, a self-supporting three-dimensional porous Co3O4 nanobelt array decorated on nickel foam (P-Co3O4 -NBA@NF) electrode with numerous active sites was successfully constructed for the oxidation of 5-Hydroxymethylfurfural (HMF) to 2,5-furan dicarboxylic acid (FDCA). The P-Co3O4 -NBA@NF electrode demonstrated high conversion efficiency, selectivity, and Faraday efficiency, as well as remarkable long-term stability. This research provides a promising electrocatalyst for biomass conversion.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Yimin Li, Enggah Kurniawan, Fumiya Sato, Takayoshi Hara, Yasuhiro Yamada, Satoshi Sato
Summary: In this study, several silica-alumina catalysts modified with Ag were examined for the dehydration of 1,3-butanediol to 1,3-butadiene. Among them, an amorphous silica-alumina catalyst (SAL-3) modified with Ag showed the highest improvement in catalytic activity and stability when operated in H2 flow. The generation of reversible acid sites was found to be the reason behind the enhanced activity and stability of this Ag/SAL-3 catalyst. The effects of various parameters on the catalytic activity of Ag/SAL-3, such as reaction temperature, contact time, Ag content, and carrier gas, were investigated.
APPLIED CATALYSIS A-GENERAL
(2024)