Article
Chemistry, Physical
Jun Ke, Wen-De Hu, Yu-Jue Du, Yang-Dong Wang, Chuan-Ming Wang, Zai-Ku Xie
Summary: Through microkinetic simulations, this study reveals that the MTO conversion in H-SAPO-34 zeolite mainly occurs through the olefin-based cycle under different reaction conditions. By controlling the reaction conditions, the contribution ratio of the aromatic-based and olefin-based cycles can be adjusted, which is essential for catalyst and process optimization.
Article
Engineering, Chemical
Yu-Ling Zhang, Xue-Gang Li, Wen-De Xiao
Summary: This study investigates the transformation mechanism of C3-C6 olefins on SAPO-34 catalyst without methanol co-feeding. A reaction network is constructed and validated, providing accurate predictions of product distribution.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Multidisciplinary Sciences
Liu Yang, Chang Wang, Lina Zhang, Weili Dai, Yueying Chu, Jun Xu, Guangjun Wu, Mingbin Gao, Wenjuan Liu, Zhaochao Xu, Pengfei Wang, Naijia Guan, Michael Dyballa, Mao Ye, Feng Deng, Weibin Fan, Landong Li
Summary: Studying the dynamic changes of SAPO-34 framework during MTO conversion, researchers found that pre-coking and water co-feeding can efficiently suppress T-O-T bond breakage during long-term continuous regenerations, thus promoting catalytic efficiency and long-term stability in commercial MTO processes.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Hongbo Jiang, Linzhi Yuan, Defei Li, Yushi Chen
Summary: This study developed a 14-lump MTO kinetic model based on SAPO-34 catalyst, and combined it with the hydrodynamic model of the fast fluidized bed reactor in the industrial SMTO process. Selective deactivation and activity difference between spent and regenerated catalysts were considered. The validated model showed good agreement with actual values, and the sensitivity analysis indicated its usefulness in guiding industrial production operations.
Article
Chemistry, Applied
Baorong Wang, Peixin Rui, Xinheng Cai, Xianqing Xie, Weilin Liao, Yibin Luo, Xingtian Shu
Summary: This study investigates the co-feeding of methanol from stripper units to enhance the ethylene selectivity in the conventional FCC process. The results show that the use of SAPO-34 catalyst under specific conditions can significantly improve the yield of ethylene and light olefins.
MICROPOROUS AND MESOPOROUS MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Shinya Kokuryo, Kazuya Tamura, Koji Miyake, Yoshiaki Uchida, Atsushi Mizusawa, Tadashi Kubo, Norikazu Nishiyama
Summary: Zr-doped SAPO-34 was synthesized to enhance the catalytic activity, highlighting the significance of Lewis acidity. The highly-dispersed Zr species in Zr-doped SAPO-34 contributed to the higher catalytic activity compared to pristine or Zr-loaded SAPO-34, indicating the strong impact of highly-dispersed Zr species on the performance of SAPO-34.
NEW JOURNAL OF CHEMISTRY
(2022)
Article
Engineering, Chemical
Huaiqing An, Hua Li, Jibin Zhou, Jinling Zhang, Tao Zhang, Mao Ye, Zhongmin Liu
Summary: This study investigated the kinetics of steam regeneration of spent SAPO-34 catalyst, showing that increasing regeneration temperature can improve catalyst performance and prolong its lifetime. Within an appropriate temperature range, steam regeneration can alter the composition of residual coke on the catalyst, promoting the production of light olefins.
CHINESE JOURNAL OF CHEMICAL ENGINEERING
(2021)
Article
Chemistry, Applied
Yadong Bai, Qinghu Zeng, Jinghui Sun, Qingfeng Song, Lei Tang, Wenwen Zhang, Zhiping Liu, Dahai Pan
Summary: In this study, bi-phases composite zeolites (SSC) consisting of SAPO-5 and SAPO-34 were successfully prepared and exhibited excellent hierarchical pore structure and catalytic performance during methanol to olefin (MTO) reaction, showing prolonged catalytic life and increased selectivity for light olefins.
JOURNAL OF POROUS MATERIALS
(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
Engineering, Chemical
Diego Zapater, Javier Lasobras, Jaime Soler, Javier Herguido, Miguel Menendez
Summary: The deactivation profile of an SAPO-34-based catalyst was studied in a fixed-bed reactor, revealing the need for further research on the deactivation mechanism of SAPO-34.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2021)
Article
Chemistry, Multidisciplinary
Weili Dai, Landong Li, Chang Wang, Liu Yang, Mingbin Gao, Xue Shao, Guangjun Wu, Naijia Guan, Zhaochao Xu, Mao Ye
Summary: This study presents a strategy of combining precoking and steaming to construct active naphthalenic species within SAPO-34 catalyst, achieving both high olefin selectivity and prolonged catalyst lifetime in methanol-to-olefin conversion. The spatiotemporal distribution and evolution of the naphthalenic species during the precoking and steaming processes were elucidated. This strategy shows promising prospects for commercial SAPO-34 catalyst in the methanol-to-olefin industry.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Engineering, Chemical
Fen-e Gao, Jing-yao Liu
Summary: Experimental study shows that Zn2+ modified H-SAPO-34 (Zn@H-SAPO-34) promotes the formation of aromatic species in the initial stage of methanol to olefin (MTO) reaction. This research investigated the possible reaction pathways of diene formation on H-SAPO-34 with and without Zn doping using density functional theory (DFT). It was found that the synergistic effect of Bronsted acid sites (BAS) and Lewis acid sites (LAS) on Zn@H-SAPO-34 enhances the formation activity of diene.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Chemistry, Applied
Chao Sun, Aijuan Zhao, Yaquan Wang, Ziyang Wang, Jingjing Zhao, Taotao Zhao, Wenrong Liu, Mingxue Shi, Jiaxin Lu, Shuhui Wu, Lingzhen Bu
Summary: The hierarchical SAPO-34 aggregates were synthesized with the assistance of organosilane TPED and using morpholine as the template. Different amounts of TPED led to varying morphologies, compositions, and acid properties of the resulting aggregates. The addition of TPED played a pivotal role in the formation of hierarchical SAPO-34 aggregates, which exhibited significant improvement in methanol to olefin reaction compared to conventional SAPO-34.
MICROPOROUS AND MESOPOROUS MATERIALS
(2021)
Article
Engineering, Chemical
Bijan Hejazi, Neda Shabany
Summary: A two-phase model based on SAPO-34 catalyst particles was developed for simulating a bubbling fluidized bed reactor and catalyst regenerator. The model showed good agreement with experimental data and was successfully used for design and optimization of the MTO process. The development of this model provides convenience for the analysis of the MTO process.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2022)
Article
Chemistry, Multidisciplinary
Runze Jin, Haobin Hu, Jiaofei Wang, Zhuangzhuang Zhang, Chengyi Dai, Xiaoxun Ma
Summary: Dividing the traditional methanol to aromatics reaction into two steps using SAPO-34 and Zn/ZSM-5 as catalysts can significantly improve the aromatic selectivity through optimized loading methods and ratios.
NEW JOURNAL OF CHEMISTRY
(2022)
Article
Chemistry, Physical
Wenjun Dong, Jiamin Yuan, Jingyi Tan, Xiaomin Tang, Wentao Liu, Anmin Zheng, Wei Chen
Summary: Kinetic quantum sieving (KQS) based on pore size and chemical affinity quantum sieving (CAQS) based on adsorption site are two common methods for separating hydrogen isotope mixtures using porous materials. This study investigates the effectiveness of alkali earth metals (Be, Mg, and Ca) doped into UiO-67 in promoting H2/D2 separation. Density functional theory calculations reveal that Be doping shows superior H2/D2 separation performance compared to other alkali earth metal dopants and unsaturated metal sites in metal-organic frameworks based on CAQS. The predicted D2/H2 selectivity of Be-doped UiO-67 at 77 K is even higher than the best experimental result, indicating its strong H2/D2 separation performance.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Yuanlong Han, Jiamin Yuan, Mengjiao Xing, Jian Cao, Zhiqiang Chen, Ling Zhang, Zhichao Tao, Zhiqiang Liu, Anmin Zheng, Xiaodong Wen, Yong Yang, Yongwang Li
Summary: Shape-selective catalysis plays a crucial role in the hydroisomerization of n-alkanes. This study investigates the impact of zeolite channel size on the product distribution and reaction pathway by preparing and characterizing 1D zeolites with variable pore sizes. The results reveal that the reaction activity and product selectivity are highly correlated with the zeolitic channel size, with a 0.3 angstrom difference critical for isomer selectivity. Larger channel sizes offer less steric constraints but lead to more severe cracking. Therefore, optimizing the channel dimension within a certain range is important for the development of efficient isomerization catalysts.
NEW JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Physical
Wei Rao, Xiaomin Tang, Kaifeng Lin, Xianzhu Xu, Hongqiang Xia, Yanqiu Jiang, Zhiqiang Liu, Anmin Zheng
Summary: In this study, it is found that zeolites with continuum intersecting channels play a crucial role in diffusion processes, with the ability to switch diffusion pathways under different loadings. This discovery has potential applications in separating products and byproducts in heterogeneous catalysis.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Jiaqi Shi, Junyi Hu, Qinming Wu, Wei Chen, Zhuoya Dong, Anmin Zheng, Yanhang Ma, Xiangju Meng, Feng-Shou Xiao
Summary: We have successfully synthesized a novel six-membered ring molecular sieve, ZJM-9, with fully open micropores through a reconstruction route. Unlike traditional six-membered ring molecular sieves, ZJM-9 exhibits a lower desorption temperature and efficient selective dehydration performance, which may offer an opportunity for saving more energy in dehydration processes.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Multidisciplinary Sciences
Jiamin Yuan, Mingbin Gao, Zhiqiang Liu, Xiaomin Tang, Yu Tian, Gang Ma, Mao Ye, Anmin Zheng
Summary: The ultrafast transport of adsorbates in confined spaces is a goal pursued by scientists. However, diffusion will be generally slower in nano-channels, as confined spaces inhibit motion. Here, researchers demonstrate that the movement of long-chain molecules increases with a decrease in pore size, indicating that confined spaces promote transport. Inspired by a hyperloop running on a railway, they establish a superfast pathway for molecules in zeolites with nano-channels. This unique hyperloop-like diffusion offers insights into molecule diffusion under confinement and has potential applications in selecting efficient catalysts for rapid transport in the industrial field.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Zhili Wang, Dong Xiao, Kuizhi Chen, Caiyi Lou, Lixin Liang, Shutao Xu, Guangjin Hou
Summary: Increasing research has revealed the complexity of active sites in zeolite catalysts, making it challenging to effectively characterize them, especially for a molecular-level understanding. Trimethylphosphine (TMP) is found to have strong catalytic meanings as proven by NMR-assisted 31P-27Al internuclear distance measurement and comprehensive 2D heteronuclear correlation (HETCOR) NMR experiments. The TMP-binding site is identified as special Al-OH groups, originating from partially bonded framework Al(IV)-2 species.
Article
Nanoscience & Nanotechnology
Peng Zhang, Xiaoxu Wang, Xianfeng Yi, Qi Ou, Changjiu Xia, Xinxin Peng, Xiaoxin Zhang, Anmin Zheng, Yibin Luo, Xingtian Shu
Summary: In this study, pure-silicon zeolites were synthesized to investigate their catalytic performance in the vapor-phase Beckmann rearrangement of cyclohexanone oxime. Among the various zeolites tested, S-1 zeolite with plentiful silanol nests exhibited superior catalytic performance, attributed to its diverse silanol distribution.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Zihao Wang, Tongtong Meng, Jiani Xu, Yanfeng Shen, Yida Zhou, Yuhan Liu, Dong Fan, Xinmei Liu, Shutao Xu, Zhengxing Qin
Summary: NH4F etching was used as a chemical scissors to cut zeolites into nanosized crystals with higher solubility for subsequent synthesis toward nanosized dimensions. The tailor-made seeds reduced the size of the synthetic products, when compared to the synthesis seeded by the uncut sample and without seeding.
CRYSTAL GROWTH & DESIGN
(2023)
Article
Chemistry, Inorganic & Nuclear
Vinicius Martins, Bryan E. G. Lucier, Zhiqang Liu, Heng Liang, Anmin Zheng, Victor V. Terskikh, Wanli Zhang, Bligh E. Desveaux, Yining Huang
Summary: One- and two-dimensional NMR experiments and computational methods were used to investigate the adsorption locations, dynamics, and interactions of CO2 and H2O in the ultramicroporous ZnAtzOx MOF. This experimental methodology can be applied to explore humid carbon capture and storage applications in other MOFs.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Ye Ma, Junyi Hu, Kai Fan, Wei Chen, Shichao Han, Qinming Wu, Yanhang Ma, Anmin Zheng, Eduard Kunkes, Trees De Baerdemaeker, Andrei-Nicolae Parvulescu, Nils Bottke, Toshiyuki Yokoi, Dirk E. De Vos, Xiangju Meng, Feng-Shou Xiao
Summary: Through modifying classic organic templates and designing a new organic template with high compatibility to ITR zeolite, the Ge-free synthesis of ITR structures including pure silica, aluminosilicate, and borosilicate ITR zeolites is achieved for the first time. These materials exhibit high crystallinity and over 95% ITR content. The obtained aluminosilicate ITR zeolite shows excellent propylene selectivity and long lifetime in the methanol-to-propylene reaction compared to conventional aluminosilicate ZSM-5 zeolite. The design strategy of organic templates offers a new opportunity for rational syntheses of novel zeolites and highly efficient zeolite catalyst development in the future.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Inorganic & Nuclear
Xiaosi Zhang, Miao Yang, Ye Wang, Caiyi Lou, Shutao Xu, Peng Tian, Zhongmin Liu
Summary: Seed-assisted synthesis has great potential in modifying inorganic microporous materials and enhancing synthesis efficiency. However, the understanding of this mechanism is still insufficient, especially in the case of silicoaluminophosphate (SAPO) molecular sieve systems. In this study, the seed-assisted synthesis of SAPO-34 was investigated using various seeds with different structures, compositions, and morphologies. The findings reveal that double 6-ring (d6r) units and complex Si environments are key features for an effective SAPO seed, and heteronuclear seeds can improve the catalytic performance of SAPO-34 in methanol-to-olefins (MTO) reactions.
INORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Multidisciplinary
Xianfeng Yi, Wei Chen, Yao Xiao, Fengqing Liu, Xin Yu, Anmin Zheng
Summary: Understanding the variations of chemical bonds is crucial for chemical processes, but visualizing them experimentally remains a challenge. In this study, different hydrogen-bonding configurations were manipulated by regulating the proton-donating ability of proton donors, and the electronic properties of proton donors and acceptors were simultaneously monitored using advanced 2D NMR spectroscopic technique. The evolution of hydrogen bonds was visualized in diverse acid-base interaction complexes during proton transfer, providing new insights into the nature and evolution of hydrogen bonds.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Inorganic & Nuclear
Benhan Fan, Dali Zhu, Linying Wang, Shutao Xu, Yingxu Wei, Zhongmin Liu
Summary: The water-induced dealumination mechanism of zeolites under hydrothermal conditions was investigated. It was found that the hydrolysis of the Al-O bond by water molecules caused dealumination. The hydrolysis generated framework-associated Al species and extra-framework aluminum (EFAL) species that stabilized the zeolite framework through electrostatic interaction with the Bronsted acid sites (BASs).
INORGANIC CHEMISTRY FRONTIERS
(2022)
Review
Chemistry, Multidisciplinary
Wei Chen, Xianfeng Yi, Zhiqiang Liu, Xiaomin Tang, Anmin Zheng
Summary: This paper reviews the stabilization of carbocations in zeolites and summarizes advanced characterization methods for capturing carbocations. It clarifies the relationship between the activity and stability of carbocations in zeolite-catalyzed reactions.
CHEMICAL SOCIETY REVIEWS
(2022)
Article
Chemistry, Physical
Nan Chen, Jin Zhang, Yating Gu, Wenna Zhang, Kaipeng Cao, Wenhao Cui, Shutao Xu, Dong Fan, Peng Tian, Zhongmin Liu
Summary: This study designed a series of bulky gemini-type bis(methylpyrrolidinium) dications as efficient OSDAs for MOR zeolite, improving the distribution of acid sites in the side pockets of MOR and enhancing the catalytic activity in the DME carbonylation reaction.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)