Article
Chemistry, Multidisciplinary
Dongliang Wang, Junqiang Zhang, Peng Dong, Guixian Li, Xueying Fan, Yong Yang
Summary: The article proposes a short process to improve the economic efficiency of toluene methylation by enhancing PX selectivity. The new process considers various factors and optimizes the toluene methylation process, achieving high raw material utilization rates and economic value.
Article
Engineering, Chemical
He Han, Anfeng Zhang, Limin Ren, Xiaowa Nie, Min Liu, Yi Liu, Chuan Shi, Hong Yang, Chunshan Song, Xinwen Guo
Summary: A coke resistant (Pt + Ni)/ZSM-5 zeolite catalyst is developed for shape-selective alkylation of toluene with methanol to produce para-xylene, providing excellent stability and high para-selectivity by tuning the pore structure and acid properties of the zeolite, as well as inhibiting coke formation through the co-existence of Pt and Ni species.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Chemistry, Physical
Bangfen Wang, Ni Wang, Yuhai Sun, Hailin Xiao, Mingli Fu, Shuhua Li, Hong Liang, Zhiwei Qiao, Daiqi Ye
Summary: This study applied a dielectric barrier discharge plasma to modify the performance of Pt/CeO2 catalyst for toluene oxidation. Different plasma discharge times were used and it was found that discharge time significantly affected the catalytic activity of Pt/CeO2 catalyst. The Pt/CeO2-PT3 (30 min) and Pt/CeO2-PT6 (3 h) catalysts showed improved catalytic activity, while the Pt/CeO2-PT5 (2 h) catalyst exhibited decreased activity due to surface carbon deposition.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Aysel Niftaliyeva, Ali Karaduman, Nazar Hussain Kalwar, Ahmet Avci, Erol Pehlivan
Summary: Metallic and bimetallic nanoparticles of Ag, Ni, Cu were synthesized using metal nitrate salts and loaded into ZSM-5 zeolite framework. Characterization revealed preservation of zeolite structure with modified metal NPs, leading to partial blockage of micropores. The catalytic activity of Ag NP-modified ZSM-5 showed increased toluene methylation and p-xylene selectivity, with high stability and reusability demonstrated.
RESEARCH ON CHEMICAL INTERMEDIATES
(2022)
Article
Chemistry, Multidisciplinary
Wu Wen, Tianci Xiao, Beibei Feng, Chaoqun Zhou, Jian Li, Hao Ma, Zhongyue Zhou, Ying Zhang, Jiuzhong Yang, Zhandong Wang, Fei Qi, Jun Bao, Chengyuan Liu, Yang Pan
Summary: In situ synchrotron radiation photoionization mass spectrometry experiments reveal that increased formaldehyde generation over Ga2O3 species plays a key role in promoting the production of aromatic compounds.
COMMUNICATIONS CHEMISTRY
(2022)
Article
Chemistry, Applied
Xuemin Li, Shang-Tien Tsai, Kevin C-W Wu, Owen J. Curnow, Jungkyu Choi, Alex C. K. Yip
Summary: By using different structure-directing agents and crystallization methods, it is possible to adjust the particle size of zeolites, obtain zeolites with different morphologies, and evaluate their selectivity in toluene methylation reactions.
MICROPOROUS AND MESOPOROUS MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Yan Zhao, Xinhui Ma, Dongmei Ren, Yunsheng Xia
Summary: The effect of nano-scale and micron-scale P2O5-ZSM-5 on para-selectivity was investigated, and the results showed that P2O5-ZSM-5 aggregates exhibited the highest para-selectivity.
JOURNAL OF NANOPARTICLE RESEARCH
(2022)
Article
Chemistry, Applied
Tingjun Fu, Lihan Jia, Guoqiang Hou, Zhong Li
Summary: Dealuminization of aluminium-containing ZSM-5 creates silanol nests, improving catalytic activity. However, the damaged microporous structure leads to catalyst deactivation. In this study, highly stable alkylation on ZSM-5 is achieved through deboronation treatment. The formation of silanol nests promotes toluene adsorption and inhibits methanol self-reaction, resulting in efficient alkylation. The microporous structure of deboronized ZSM-5 is well-maintained, leading to improved catalytic stability compared to traditional dealuminized ZSM-5.
MICROPOROUS AND MESOPOROUS MATERIALS
(2023)
Article
Chemistry, Physical
Lucie Desmurs, Claudia Cammarano, Olinda Gimello, Anne Galarneau, Vasile Hulea
Summary: This study investigates the strategy of introducing mesopores to ZSM-5 catalysts for improving the selectivity of para-xylene production through toluene alkylation. The results show that although the mesoporous ZSM-5 catalysts did not enhance the para-xylene selectivity, they exhibited less deactivation compared to the parent ZSM-5. Therefore, combining mesopore introduction with other shape-selective strategies, such as passivating the external surface acidity, could be an interesting research direction.
Article
Engineering, Chemical
Feng Xiong, Chen Ji, Shengzhi Gan, Peng Liang, Yi Huang, Jin Shang, Baoyu Liu, Jinxiang Dong
Summary: Mesoscopically structured ZSM-5 nanosheets were prepared as highly active catalysts for the alkylation between toluene with methanol. The Bronsted acid sites of ZSM-5 nanosheets were mainly distributed on the external surface in aluminum-rich zeolites, and high alkalinity was required for silica-rich systems to dissolve silica species in order to finish the self-assemble process, leading to ZSM-5 nanosheets with high alkalinity presenting enhanced catalytic performance. Moreover, the optimized ZSM-5-50-2.5 showed good effectiveness and stability in the alkylation reaction between toluene and methanol.
Article
Chemistry, Physical
Zhe Hong, Xiaoxia Wang, Fangtao Huang, Lei Miao, Yanqing Huang, Zhirong Zhu
Summary: Modification of Cs/X with highly dispersed Pt nanoparticles improved reaction activity and durability in the side-chain alkylation of toluene with methanol. The high catalytic performance is attributed to Pt species promoting C-H bond activation in the methyl group of toluene and inhibiting the formation of coke.
CATALYSIS SCIENCE & TECHNOLOGY
(2021)
Article
Chemistry, Physical
Shizheng Zhang, Han Liu, Lin Deng, Gongde Wu, Jie Wan, Yanjun Liu, Xiankun Yu, Xiaojun Yang
Summary: In this study, Cu-Mn oxide catalysts supported on ZSM-5 zeolite were modified by acid leaching and used for the catalytic oxidation of toluene. The acid modification improved the pore structure, surface area, and the formation of Mn4+ and Cu2+ species, resulting in excellent performance of the catalyst in the decomposition of toluene.
Article
Multidisciplinary Sciences
Qingteng Chen, Jian Liu, Bo Yang
Summary: This study identifies the key steps in the methylation of toluene to produce p-xylene over a zeolite catalyst, with methylation being found as the rate-determining step. The research also highlights that the diffusion of m-xylene along the channel is more challenging than its isomerization to p-xylene, further enhancing the selectivity of p-xylene formation.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Meng Li, Fulin Yang, Jinfa Chang, Alex Schechter, Ligang Feng
Summary: Hydrogen energy has the advantages of cleanliness, high efficiency, and renewability, making it a potential energy storage carrier. Electrocatalytic water splitting is a promising method for hydrogen generation, but the slow kinetics of the oxygen evolution reaction (OER) hinders its practical application. In this study, the methanol oxidation reaction (MOR) with a lower theoretical potential was proposed as a replacement for OER in hydrogen generation. A bifunctional catalyst consisting of ultrafine Pt nanoparticles supported on MoP-NC nanospheres (Pt/MoP-NC) was developed, and it exhibited high performance in methanol electrocatalysis and hydrogen evolution reaction.
ACTA PHYSICO-CHIMICA SINICA
(2023)
Article
Chemistry, Physical
Lei Li, Yuanhao Jin, Meijie Wei, Renqi Wang, Zhaoyang Fei
Summary: Hollow structural MnCoOx catalysts were prepared using metal-organic frameworks as sacrificial templates. The hollow MnCoOx nanocages showed higher performance in toluene oxidation compared to MnCoOx nanoparticles synthesized by co-precipitation. The addition of Pt species greatly boosted the catalytic performance of hollow Pt/MnCoOx-H nanocages, indicating a synergistic effect between Pt and the support.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Biology
Yuyan Wang, Akhgar Ghassabian, Bo Gu, Yelena Afanasyeva, Yiwei Li, Leonardo Trasande, Mengling Liu
Summary: This paper introduces a new method, semiparametric partial-linear single-index DL quantile regression, to study the effects of time-dependent exposure mixtures on different quantiles of outcome. Through simulations and application studies, the performance and value of this method are demonstrated.
Article
Biology
Peng Jin, Wenbin Lu, Yu Chen, Mengling Liu
Summary: This paper proposes a semiparametric change-plane model and a doubly robust test statistic for detecting and assessing subgroups with differential treatment effects under a continuous treatment. The proposed method handles various types of outcomes and provides extensions with nonparametric estimation approaches. Extensive simulation studies evaluate the performance of the proposed method.
Article
Agricultural Engineering
Fan Wang, Chenglong Wen, Mohong Lu, Peng Zhang, Jie Zhu, Mingshi Li, Yuhua Shan, Chunshan Song
Summary: Mo2N@NC/SBA-15 catalysts with high stability and dispersion were prepared using MoCl5 and dicyandiamide as Mo and C/N sources, respectively. During the carbonization process under H2 at an elevated temperature, Mo2N was formed in situ while dicyandiamide was converted to N-doped carbon (NC). The presence of N-doped carbon species around Mo2N NPs inhibited the aggregation of Mo2N NPs, resulting in the generation of ultrafine Mo2N nanoparticles. Mo2N@NC/SBA-15 catalysts exhibited high hydro-deoxygenation activity and aromatic compound selectivity. The selectivity towards aromatic products reached 92% and guaiacol conversion reached 99% at 380 degrees C and 2 MPa.
BIOMASS & BIOENERGY
(2023)
Article
Energy & Fuels
Pawnprapa Pitakjakpipop, Chunshan Song
Summary: This study examined the effects of different supports on the activity and selectivity of nickel phosphide catalysts in anisole hydrodeoxygenation. Ni2P/CeO2 showed the highest activity among the synthesized supports and common materials. Ni2P/TiO2-CeO2 exhibited superior reactivity and higher cyclohexane selectivity compared to Ni2P/CeO2. The choice of support also influenced the product distributions and HDO pathways. Both Ni2P/CeO2 and Ni2P/TiO2-CeO2 are promising catalysts for tunable production of benzene and cyclohexane, respectively.
Article
Energy & Fuels
Ajuan Zhou, Jiaxing Zhang, Hong Yang, Shujie Shang, Anfeng Zhang, Chunshan Song, Xinwen Guo
Summary: This study explores the rational design of Pt/ZSM-5 bifunctional catalysts for alkylating benzene with ethane. It reveals that the Si/Al ratio of ZSM-5 regulates the dispersion and particle size of Pt, and the interaction between H+ of ZSM-5 and Pt plays a crucial role in controlling the product distribution in the reaction.
Article
Chemistry, Applied
Yu Tang, Yi Cui, Gaosheng Ren, Ke Ma, Xiaoxun Ma, Chengyi Dai, Chunshan Song
Summary: In this study, copper-mordenite zeolite (Cu-MOR) and non-thermal plasma were used to efficiently convert methane and water into methanol and hydrogen at low temperature without CO2 formation. The reaction mechanism involves the excitation of methane under plasma conditions, followed by adsorption on the Cu-2-(μ-O)(2+) active sites and facilitated formation of methanol through co-adsorption of water. However, prolonged reaction time led to the reduction of Cu-2-(μ-O)(2+) and carbon deposition on the catalyst surface, causing a decrease in catalytic activity. Nevertheless, the presence of oxygen rejuvenated the catalyst and prevented carbon deposition, maintaining the catalytic activity.
FUEL PROCESSING TECHNOLOGY
(2023)
Article
Engineering, Chemical
Fei Yuan, Guanghui Zhang, Mingrui Wang, Jie Zhu, Miao Zhang, Fanshu Ding, Zening Cheng, Chunshan Song, Xinwen Guo
Summary: This study reports a series of Fe-Co bimetallic catalysts derived from Fe-Co-Mg layered double hydroxides (LDHs) with different Fe/Co ratios for converting CO2 to light olefins. The best catalyst, FeCo-9:1-LDH, showed a high selectivity of C-2-C-4(=) over 36% at a CO2 conversion higher than 40%. The catalyst can be carburized to Co-modified iron carbide (Fe5C2), which exhibits higher CO2 conversion and C-2-C-4(=) selectivity compared to the catalyst prepared by impregnating Co and Fe onto MgO support.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Chemistry, Physical
Liangyu Li, Jiawei Tang, Zhengqin Liu, Yiren Wang, Yong Jiang, Gang Sha
Summary: The micro-alloying effects of Ni on the microstructure evolution and mechanical properties of an Al-Zn-Mg-Cu-Sc-Zr alloy were thoroughly investigated using electron/atom microscopic characterization and first-principles calculations. A trace addition of 0.2 wt% Ni can induce a new primary phase of Al3(Ni, Cu) and refine the grain size to 23 μm. It was found that Ni promotes the precipitation of the eta phase, improves its thermal stability, and enhances the GB binding by segregating to Al GBs. The Ni micro-alloyed Al-Zn-Mg-Cu-Sc-Zr alloys exhibit high strength and thermal stability with acceptable plasticity, even with a low Cu/Mg atomic ratio (approximately 0.22), compared to most 7055 Al alloys.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Respiratory System
Alexis L. Sharpe, Joan Reibman, Beno W. Oppenheimer, Roberta M. Goldring, Mengling Liu, Yongzhao Shao, Isaac Bohart, Benjamin Kwok, Tatiana Weinstein, Doreen Addrizzo-Harris, Daniel H. Sterman, Kenneth I. Berger
Summary: This study used an augmented cardiopulmonary exercise test to evaluate small airway function during and following exercise in asthma patients with normal spirometry. Abnormalities in small airway function during exercise and small airway hyperreactivity following exercise were found in these patients, suggesting a relationship between small airway abnormalities and exertional symptoms.
Article
Computer Science, Interdisciplinary Applications
Liang Liang, Minliang Liu, John Elefteriades, Wei Sun
Summary: This study introduces PyTorch-FEA, a new library of finite-element analysis code and methods, for solving forward and inverse problems in solid mechanics. PyTorch-FEA shows significant improvements in computational time and accuracy compared to commercial FEA software, especially when combined with deep neural networks in inverse methods.
COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE
(2023)
Article
Energy & Fuels
Mengmeng Zhang, Shuang Wang, Xiaowa Nie, Fanshu Ding, Chunshan Song, Xinwen Guo
Summary: Converting CO2 into chemicals and fuels is an effective solution to address CO2 emissions. This study investigated the reaction mechanism of hydrocarbons formation from CO2 hydrogenation on CHI-Fe5C2 (111) surface using DFT calculations. It was found that introducing a second transition metal could effectively tune the product selectivity.
Article
Physics, Applied
Yuxiang Gong, Shiyu He, Jianning Zhang, Yiren Wang, Yong Jiang
Summary: In this study, the nucleation of (O, X)-core (X = La, Ce, and Hf) nano-clusters in multi-element micro-alloyed nanostructured ferritic alloys (NFAs) was investigated using first-principles calculations. It was found that the (O-O) pair was the most basic core structure of all types of nano-clusters. Yttrium had the strongest affinity with the (O-O) pairs and played a crucial role in initiating the nucleation of nano-clusters. The availability of different micro-alloying solute species around the (O-O) pairs strongly influenced the nucleation and composition of nano-clusters in NFAs.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Yi Liu, Yuxiang Gong, Yiren Wang, Yong Jiang, Chunlei Shen, Xiaosong Zhou, Xinggui Long
Summary: The surface structures and relative stabilities of low-miller-index surfaces of & gamma;-TiH and & gamma;-TiH2 have been investigated as a direct function of environmental conditions. It was observed that the dominant surface termination of & gamma;-TiH changes with increasing p(H2), while & gamma;-TiH2 is stable only when p(H2) exceeds a certain threshold. The surface phase diagrams and surface energies of & gamma;-TiH and & gamma;-TiH2 were also determined.
JOURNAL OF MATERIALS SCIENCE
(2023)
Article
Physics, Fluids & Plasmas
Yiren Wang, Busra Demir, Hashem Mohammad, Ersin Emre Oren, M. P. Anantram
Summary: DNA exists in a solvent environment, and the solvent conditions play a vital role in determining DNA structure and conductance. Modeling studies show that counterions in dry DNA affect electron transmission, but in solution, their role is negligible.
Article
Energy & Fuels
Jiaxing Zhang, Fei Yuan, Anfeng Zhang, Guanghui Zhang, Limin Ren, Chunshan Song, Xinwen Guo
Summary: This study developed a tandem catalyst Fe-Co/HZSM-5 for the direct conversion of CO2 into gasoline fuel. The use of HZSM-5 nanosheets with short diffusion channels and appropriate acid property improved the selectivity and yield of gasoline fuel, while preventing catalyst deactivation.