Article
Engineering, Chemical
Pengfei Chu, Hu Liu, Kai Cai, Yunduo Liu, Ying Li, Yue Wang, Shengping Wang, Shouying Huang, Xinbin Ma
Summary: This study systematically investigated the effect of pseudoboehmite on the mechanical strength and catalytic performance of extruded MOR catalyst. The interlayer water content of pseudoboehmite was found to influence the peptization process, leading to differences in mechanical strength and pore structure. The performance of the extruded MOR catalyst in DME carbonylation was discussed based on textural parameters and acidic properties. Furthermore, diffusion experiments were conducted to quantitatively analyze the influence of pseudoboehmite on mass transfer performance. These results provide important guidance for the development of shaped zeolite catalysts in industry.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Andreas Billion, Jonas Schulte, Andreas Vogel, Felix Hilfinger, Ingo Krossing
Summary: A novel continuous route for synthesizing oxymethylene dimethyl ethers (OMEn) by the reaction of molecular formaldehyde and dimethyl ether is presented. Acidic, porous, and thermally stable zeolites proved to be effective catalysts for this reaction. The results contribute to a better understanding of the complex reaction network in the OMEn synthesis and provide important insights for establishing an energy efficient and sustainable OMEn production process.
Article
Engineering, Chemical
Pei He, Jianhao Wang, Ying Li, Shouying Huang, Mei-Yan Wang, Yue Wang, Jing Lv, Xinbin Ma
Summary: Microporous zeolites are commonly used as industrial catalysts, with Bronsted acidity playing a crucial role in their performance and stability. This study demonstrates an efficient synthesis method for MOR zeolite, which maintains specific acidity while shortening the synthesis period. The ultrafast synthesis method shows no negative impact on the textural and acidic properties of zeolites, resulting in improved catalytic activity and stability for MOR.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2021)
Article
Energy & Fuels
Xiao-Bo Feng, Feng Chen, Zi-Meng He, Xiao-Yan Zhao, Jing-Pei Cao
Summary: This study investigates the performance of T zeolite in the dimethyl ether (DME) carbonylation reaction and proposes a method to improve catalytic stability. The results show that the catalytic stability can be largely improved by selectively shielding specific acid sites. In addition, it is found that coke and methyl acetate formation are catalyzed by different acid sites. The transition-state shape selectivity for methyl acetate formation is also influenced by the pore structure.
Article
Chemistry, Multidisciplinary
Zhiping Xiong, Guodong Qi, Ensheng Zhan, Yueying Chu, Jun Xu, Jiake Wei, Na Ta, Aijing Hao, Yan Zhou, Feng Deng, Wenjie Shen
Summary: Mordenite is an effective catalyst for the carbonylation of dimethyl ether to methyl acetate, and the activity is determined by the number of Bronsted acid sites in its 8-member-ring pore. Experimental evidence shows that the specific activity of the T3 site is 4 times higher than that of the T4 site at 473 K. This study provides insights into the unique reaction mechanism at the T3 site.
Article
Engineering, Chemical
Li-Yun Zhang, Xiao-Bo Feng, Zi-Meng He, Feng Chen, Chang Su, Xiao-Yan Zhao, Jing-Pei Cao, Yu-Rong He
Summary: In this study, a series of Fe-doped MOR zeolites were designed using oxalic acid as the complexing reagent by a template-free method, leading to significantly enhanced stability and selectivity in DME carbonylation. Contrary to conventional understanding, the decrease in B8-MR is beneficial for the reaction.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Energy & Fuels
Yan-Ting Zhang, Ni-Ni Zhang, Sheng-Li Chen, Hui Dang, Tao Wu
Summary: The catalysts based on selectively dealuminated Beta zeolites showed higher BTX selectivity and lower coke formation rate compared to those based on conventionally dealuminated Beta zeolites.
Article
Chemistry, Inorganic & Nuclear
Lijun Luo, Libo Zheng, Xuejia Zhang, Fengzhi Jiang, Lihong Xia, Jianhui Dai, Demei Meng
Summary: The modified T-H beta (25, 50) zeolites showed significantly higher adsorption capacity for BPA compared to HY and HZSM-5, due to their larger pore size and hydrophobic nature. The acid treatment-calcination method proved to be effective in modifying H beta for the removal of hydrophobic organic pollutants.
JOURNAL OF SOLID STATE CHEMISTRY
(2022)
Article
Chemistry, Physical
Benjamin Niethammer, Ulrich Arnold, Jorg Sauer
Summary: The influence of zeolite framework type on the conversion of DME to hydrocarbons was investigated, and remarkable differences in catalytic performance were observed among *MRE, MFI, and TON zeolite catalysts. The *MRE zeolite showed exceptionally high yield of olefins and a substantial ratio of products in the C5-C11 chain length range. By adjusting the reaction parameters, the optimal combination of selectivity and deactivation resistance for each material was identified. The olefin-rich DTH product of the *MRE zeolite offers potential for further conversion to valuable low-emission fuels.
APPLIED CATALYSIS A-GENERAL
(2023)
Article
Chemistry, Applied
Xiu Bai, Jin Zhang, Chong Liu, Shutao Xu, Yingxu Wei, Zhongmin Liu
Summary: The acidity of zeolites, which is crucial for catalytic reactions, is closely related to the presence of framework aluminum. Dealumination, achieved through high-temperature hydrothermal treatment, increases the Si/Al ratio of zeolites and generates new aluminum species, affecting the pore structure and catalytic performance of zeolites. In this study, different aluminum species in H-MOR zeolite were identified during high-temperature hydrothermal treatment using 27Al MQ MAS NMR. The transformation process of framework aluminum into amorphous non-framework aluminum was revealed, along with the formation of pentahedrally and hexahedrally coordinated aluminum species.
MICROPOROUS AND MESOPOROUS MATERIALS
(2023)
Article
Engineering, Chemical
Yaqiong Zhi, Yaquan Wang, Wenrong Liu, Jiaxin Lu, Mingxue Shi, Shuhui Wu, Lingzhen Bu, Mengyao Yang, Zhiqiang Wang, Juncai Sang, Niandong Guo, Kailiang Chu, Yitong Huang, Liping Qu
Summary: A series of binder-free mordenite (MOR) zeolites were successfully prepared using shaped precursors containing aluminosilicate and MOR seeds. Different morphologies of MOR seeds were synthesized using CTAB as a crystal growth inhibitor and pore filler, and their effects on the performance of binder-free MOR were studied. The synthesized binder-free MOR exhibited high activity, 100% selectivity, and high stability in the dimethyl ether carbonylation reaction, attributed to the larger surface area and more mesopores.
ASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING
(2023)
Article
Chemistry, Multidisciplinary
Rongsheng Liu, Benhan Fan, Wenna Zhang, Linying Wang, Liang Qi, Yingli Wang, Shutao Xu, Zhengxi Yu, Yingxu Wei, Zhongmin Liu
Summary: Selective relocation of aluminum atoms in mordenite framework can generate and intensify active sites in zeolite, improving selectivity and lifetime of catalytic reactions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Multidisciplinary Sciences
Puneet Kumar Chaudhary, Racha Arundhathi, Mahesh W. Kasture, Chanchal Samanta, Rakesh Vankayala, Chiranjeevi Thota
Summary: Crystalline beta zeolite molecular sieve with a SiO2/Al2O3 molar ratio of 28.5 was synthesized by hydrothermal crystallization and used for methanol dehydration. The micro-mesoporous beta zeolite exhibited good activity between 280 and 450°C. Dimethyl ether (DME) was the predominant product at all reaction temperatures, with a maximum selectivity of 47.9% at 300°C and a methanol turnover frequency (TOFMeOH) of 741.9 h(-1). The crystallinity, porosity, and acidity of beta zeolite were found to change in the reaction environment. Amorphous carbon deposition occurred, leading to a decrease in crystallinity to some extent. Pore broadening was observed at elevated temperatures. Regeneration cycle testing showed stable activity of beta zeolite over a 280-hour time-on-stream period.
ROYAL SOCIETY OPEN SCIENCE
(2023)
Article
Chemistry, Applied
Shanfan Lin, Yuchun Zhi, Wenna Zhang, Xiaoshuai Yuan, Chengwei Zhang, Mao Ye, Shutao Xu, Yingxu Wei, Zhongmin Liu
Summary: Using a colorimetric analysis method, the production of formaldehyde (HCHO) in methanol-to-olefins (MTO) and dimethyl ether (DME)-to-olefins (DTO) reactions over SAPO-34 was quantitatively monitored. It was found that HCHO was present in both slight and conspicuous amounts at the initial and deactivation stages of the reactions, as well as when co-fed with water or high-pressure H2. The study also revealed the weaker hydrogen transfer ability of DME compared to methanol, leading to a more prominent olefins-based cycle and suppression of reactant-induced hydrogen transfer and deactivation in DTO.
CHINESE JOURNAL OF CATALYSIS
(2023)
Article
Energy & Fuels
Tianlong Liu, Fei Ning, Qi Li, Zhonghong Li, Xiaobo Feng, Xiaoyan Zhao
Summary: Chemical etching with acids is a common method for post-treating zeolites, but it has negative effects on their structure and acidity. This study presents a new method using a buffer solution and AlF3 to treat HZSM-5 zeolite for one-step dealumination and alumination. The treated zeolites maintain high crystallinity and acidity, with the formation of secondary mesopores. The AlF3-modified zeolites exhibit higher catalytic activity in reforming lignite pyrolytic volatiles into light aromatics, suppressing coke deposition and yielding desired products.
Article
Energy & Fuels
Teguh Kurniawan, Anton Irawan, Hafid Alwan, Raden Hernanto, Wahyudi Wahyudi, Abdul Rozak Kodarif, Yazid Bindar
Summary: A novel method has been developed to estimate the coke reactivity index (CRI) using a kinetic approach. The method accurately predicts CRI based on three main coal properties and shows good agreement with experimental data. Additionally, the method successfully predicts the coke strength after reaction (CSR) and analyzes the sensitivity of coal properties to CRI.
INTERNATIONAL JOURNAL OF COAL PREPARATION AND UTILIZATION
(2022)
Review
Energy & Fuels
Oki Muraza
Summary: Sustainable energy and fuels for personal vehicles are becoming increasingly important. Transitioning from gasoline to biomass-derived liquid fuels, then to compressed natural gas, hydrogen fuel, and electric vehicles has been key in minimizing carbon pollution. Challenges remain in each generation of fuels, requiring better catalysts and energy storage materials.
Article
Engineering, Chemical
Galal A. Nasser, Ali A. Al-Qadri, Anas Karrar Jamil, Idris A. Bakare, Mohammed A. Sanhoob, Oki Muraza, Zain H. Yamani, Toshiyuki Yokoi, Qasim Saleem, Donya Alsewdan
Summary: The study investigated a series of chabazite-based catalysts that facilitate the methanol to olefins reaction, comparing the effects of different treatment methods on their reaction performance. The results showed that the catalyst modified by steam and acid treatment exhibited better stability in the MTO process.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2021)
Article
Chemistry, Multidisciplinary
Y. Zhu, K. Miyake, Y. Shu, K. Moroto, Y. Hirota, Y. Uchida, S. Tanaka, T. Zheng, M. Katayama, Y. Inada, E. Morallon, D. Cazorla-Amoros, C. Y. Kong, N. Nishiyama
Summary: Zeolite-templated carbons with curved and single-layer graphene frameworks have uniform micropores and high surface areas. The Co/N-doped ZTC synthesized in this work shows excellent catalytic performance on the oxygen reduction reaction due to the presence of single atomic Co species. This synthetic concept of fabricating single atomic transition metals coordinated with heteroatoms in ZTCs contributes to the advancement of material design for single atomic catalyst-supported porous materials.
MATERIALS TODAY CHEMISTRY
(2021)
Article
Chemistry, Applied
Galal A. Nasser, Mohammed A. Sanhoob, Idris A. Bakare, Nabil Alyassir, Mayank Vyas, Zuhair Malibari, Zain H. Yamani, Oki Muraza
Summary: OSDA-free aluminosilicate chabazite (CHA) catalysts incorporated with metals (MeCHA) by in-situ method were successfully synthesized using a green template-free method in a fluoride medium. The detailed characterizations of the catalysts showed that MeCHA preserved the inherent properties of the parent chabazite zeolite, with acidity strength dependent on the type of metal incorporated. MeCHA zeolites incorporated with Ni, B, Mg, and Fe exhibited good activity and better selectivity in the conversion of methanol to olefins compared to parent CHA.
MICROPOROUS AND MESOPOROUS MATERIALS
(2021)
Review
Chemistry, Applied
Ahmad Galadima, Ahmad Masudi, Oki Muraza
Summary: This paper evaluates the potential of cellulose-to-glucose reaction and transformation into fuels/chemicals, and analyzes the roles of catalysts such as ionic liquids, sulfonated mesoporous carbon systems, and Fe-modified zeolites in the process. It also discusses the parameters and catalyst-stability challenges of the upgrading process, and provides new directions for further research.
MICROPOROUS AND MESOPOROUS MATERIALS
(2022)
Review
Chemistry, Multidisciplinary
Ali. A. Al-Qadri, Galal A. Nasser, Ahmad Galadima, Oki Muraza
Summary: Liquified petroleum gas (LPG) is widely used due to its high heating value and clean combustibility. The synthesis of LPG from syngas can be achieved through direct, indirect, or semi-direct methods. Factors affecting the process performance include reaction temperature and pressure. The catalyst, particularly the type of zeolite used, plays a crucial role in the process.
Article
Chemistry, Multidisciplinary
Mohammed A. Sanhoob, Emad N. Shafei, Abuzar Khan, Galal A. Nasser, Idris Bakare, Oki Muraza, Mohammed Z. Al-Bahar, Ali N. Al-Jishi, Hameed H. Al-Badairy, Aniz C. Ummer
Summary: This study focuses on tuning the synthesis conditions of MFI zeolites to improve catalytic properties by optimizing mesoporosity, the balance between Bronsted and Lewis sites, and zeolite particle sizes. Different silicon sources and synthesis temperatures have significant effects on the structure and functionality of MFI zeolites, which in turn impact the shape selectivity of catalytic cracking reactions.
Article
Chemistry, Multidisciplinary
Emad N. Shafei, Ahmad Masudi, Zain H. Yamani, Oki Muraza
Summary: Nanozeolite-Y was modified using different methods and the effects on the zeolite acid sites were analyzed. It was found that the modification methods caused changes in the acidity of the zeolite, altering the acid sites. Additionally, the catalytic evaluation revealed that the evolution and product transformation of nanozeolite-Y led to catalyst deactivation.
Article
Nanoscience & Nanotechnology
M. Nasiruzzaman Shaikh, Mahmoud M. Abdelnaby, Abbas S. Hakeem, Galal A. Nasser, Zain H. Yamani
Summary: Developing efficient, robust, and highly recyclable catalysts for industrially important hydrogenation reactions is a major challenge. The Co3O4/N-Gr/Fe3O4 magnetic heterostructure, prepared from ZIF-67-derived nitrogen-doped graphitic carbon on Fe3O4 support, showed enhanced catalytic selectivity and durability. The construct demonstrated stable and reusable catalyst performance for selective hydrogenation reactions and exhibited robust nature through multiple cycles of separation and reuse.
ACS APPLIED NANO MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Galal A. Nasser, M. H. M. Ahmed, Mochamad A. Firdaus, Mohammed A. Sanhoob, Idris A. Bakare, E. N. Al-Shafei, M. Z. Al-Bahar, A. N. Al-Jishi, Z. H. Yamani, Ki-Hyouk Choi, Oki Muraza
Summary: Nano BEA zeolite catalysts were synthesized and modified by desilication and Co ion-exchange, altering the acidity of the catalysts. The conversion and yield of light olefins increased with higher reaction temperatures in the range of 400 to 600 degrees Celsius.
Article
Engineering, Environmental
Emad N. Al-Shafei, D. Robert Brown, Sai P. Katikaneni, Hameed Al-Badairy, Oki Muraza
Summary: The study investigated propane dehydrogenation assisted by CO2 using zirconia and titania catalysts. The increase of CO2 ratio led to higher propylene selectivity, while increasing the CO/H-2 ratio was important for olefins yield and catalytic stability. The presence of CO2 played an important role in enhancing propane dehydrogenation.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
