ACS Sustainable Chemistry & Engineering
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2022
·
IF 9.224
Chao Miao,Kaixuan Shang,Lixing Liang,Shumei Chen,Jing Ouyang
In this work, a Ni-based catalyst supported on a core–shell structure catalytic carrier material (Ni/ZSM-5@MCM-41) based on kaolinite tailings is reported, which exhibits excellent CO2 methanation performance at atmospheric pressure. At 400 °C, CO2 conversion and CH4 selectivity reach 80 and 97% with the space velocity of 12,000 mL gcat–1 h–1, respectively, and it can maintain good stability during the 80 h stability test. Compared with traditional Ni/ZSM-5 and Ni/MCM-41 catalysts, Ni/ZSM-5@MCM-41 has more substantial confinement effects on the active components, and the active components are more evenly dispersed on surface of the carrier. In addition, it is confirmed by the in situ diffuse reflectance infrared Fourier transform spectroscopy technique that CO2 methanation over the Ni/ZSM-5@MCM-41 catalyst follows the path of formate and CO as intermediates.
研究领域:
催化
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化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2025
·
IF 4.3
Kairui Zhang,Qiong Tang,Lei Liu,Jinxiang Dong
The alkylation reaction of benzene with n- butene can not only significantly improve the utilization rate of n- butene, but also solve the shortage problem of phenol and methyl ethyl ketone, and alleviate the surplus problem of acetone. This study demonstrates a strategic approach to engineering hierarchical ZSM-5 zeolites with controlled aluminum distributions for enhanced benzene-butene alkylation catalysis. Through aluminum precursor selection (aluminum isopropoxide, sulfate, and sodium aluminate) coupled with resin-templated synthesis, the framework Al speciation and mesopore architecture in ZSM-5 could be regulated. Advanced characterization revealed that aluminum source chemistry governs Brønsted/Lewis acid ratios, Al spatial positioning (sinusoidal/straight channels), and mesopore volume. The synthetic hierarchical ZSM-5 zeolites exhibited significant difference in catalytic performance toward benzene-butene alkylation, the Al atoms in HZ5-AIP zeolite with the largest pore size mainly in straight and sinusoidal channels, achieving 99 % conversion of n -butene (210 °C, 3 MPa, benzene/butene molar ratio = 5:1, WHSV Bu = 6 h −1 ).
研究领域:
催化化学
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材料科学
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石油化工
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2021
·
IF 13.273
Yi Yang,Yinuo Wang,Chenyang Zheng,Haowen Lin,Ruikun Xu,Huiqi Zhu,Lulu Bao,Xuhui Xu
High-efficiency phosphate removal from wastewater is crucial for protecting environmental stability. In this work, a lanthanum carbonate grafted ZSM-5 adsorbent (LC-ZSM-5) was prepared and optimized by a Box-Behnken design. The higher temperature, molar ratio of urea to lanthanum and initial lanthanum concentration are beneficial for LC-ZSM-5 synthesis, and the adsorption capacity of LC-ZSM-5 under optimistic conditions was 91.2 mg-PO 4 3- /g. The growth mechanism indicates that the LC particles grow larger with synthesis time and finally agglomerate, and 12 h is the best synthesis time. The thermodynamic results show that phosphate adsorption over LC-ZSM-5 is a spontaneously exothermic and combined physicochemical adsorption process. Kinetic studies suggest that higher temperatures help increase the phosphate adsorption rate, and chemical adsorption plays an important role during adsorption with an activation energy E a of 42.7 kJ/mol. The adsorption mechanism of the phosphate uptake process includes electrostatic attraction and ligand exchange, through which LC is changed to lanthanum phosphate (LP) during adsorption. Finally, the regeneration study revealed that LC-ZSM-5 still exhibited a high adsorption capacity after 5 cycles, showing its satisfactory regeneration ability and potential industrial application.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
ChemCatChem
·
2020
·Vol. 12
·期 15
·3880-3889
·
IF 4.853
Xingling Zhao,Jun Xu,Yueying Chu,Guodong Qi,Qiang Wang,Wei Gao,Shenhui Li,Ningdong Feng,Feng Deng
Graphical Methane activation : Different types of Ga-CH 3 species were observed in methane activation on Ga-modified ZSM-5 zeolite, evidencing different pathways for heterolytic cleavage of C−H bond of methane. Two-dimensional solid-state NMR experiments provided detailed information on the location and local environment of the Ga-CH 3 species. Methane activation on Ga-modified ZSM-5 zeolites (Ga/ZSM-5) was studied by solid-state NMR spectroscopy. Two types of Ga species, namely highly dispersed oxides and cationic Ga species, were determined by 71 Ga QCPMG NMR. The activation of methane on Ga/ZSM-5 was explored by using 13 C and 1 H MAS NMR. Four types of Ga-CH 3 species along with Ga-OH groups were observed on Ga/ZSM-5, evidencing different pathways for heterolytic cleavage of C−H bond of methane. Two-dimensional (2D) 1 H- 1 H correlation NMR experiments provide detailed information on the location and local environment of the Ga-CH 3 species by correlating the protons in Ga-CH 3 with those in Ga-OH and other hydroxyls on zeolite. The structures of different Ga-CH 3 species were further determined by 2D 1 H- 13 C heteronuclear correlation NMR experiments, which were supported by theoretical calculations. The activation routes of C−H bond in methane were proposed on Ga/ZSM-5 zeolite.
研究领域:
化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Sustainable Energy & Fuels
·
2024
·Vol. 9
·期 1
·152-171
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IF 5
Haoyu Liu,Wenbo Luo,Ke Wang,Yanlin Wang,Hong Yuan
The bolaform surfactant C6H13-N+(CH3)2-C6H12-N+(CH3)2-C6H12-O-C6H4-C6H4-O-C6H12-N+(CH3)2-C6H12-N+(CH3)2-C6H13 (BCPH-6-6-6) was synthesized and used to guide the synthesis of hierarchical ZSM-5 nanosheets (HZN) for use as zeolite catalysts. The number of acidic sites and the Al distribution in the zeolite pores were varied by changing the amounts of sodium sulfate and Al in the initial gel. The X-ray diffraction, Fourier transform infrared spectroscopy, scanning electronic microscopy, NH3 temperature programmed desorption, 27Al magic angle spinning nuclear magnetic resonance spectroscopy and N2 adsorption/desorption were used to characterize these materials. These zeolites each had a well-developed hierarchical system and specific surface areas as high as 631 m2 g−1, indicating that the BCPH-6-6-6 formed lamellar micelles based on π–π stacking. Interconnected hierarchical pore structures were retained after the templating agent was removed. The HZN sample exhibited a 90° rotational intergrowth structure and retained a large number of lamellae. The same material had a high concentration of acidic sites and contained Al in a tetrahedral coordination framework. The catalytic cracking of oleic acid using this zeolite gave light olefin yields up to 52.2% at 500 °C, exceeding the performance of conventional ZSM-5 (38.9%), and the catalyst remained active for up to 60 h. At 450 °C, the BTX selectivity of 6.72% obtained with this material also exceeded that from the conventional ZSM-5. These results were attributed to the connected hierarchical pores of the HZN, which promoted diffusion and provided higher carbon resistance.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2015
·
IF 4.321
Dongjing Liu,Weiguo Zhou,Jiang Wu
x Ce y Mn/ZSM-5 sorbents were prepared using sol–gel method and employed for H 2 S removal in the temperature range of 600–800 °C. The sorbents exhibited high performance in sulfur removal due to the cooperative effect of CeO 2 and MnO x . The presence of H 2 was unfavorable for sulfidation and obviously shortened the breakthrough time and reduced the sulfur capacity. However, the existence of CO had little impact on the sulfur-removal performance. The characterization results revealed that the ZSM-5 structure remained intact during preparation and sulfidation process. And active species, such as CeO 2 and Mn 2 O 3 , were well dispersed on ZSM-5, which would suppress the mechanical disintegration and improve the thermal stability of x Ce y Mn/ZSM-5.
研究领域:
环境催化
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能源化学工程
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材料科学
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无机功能材料
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气体净化技术
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2025
·
IF 13.2
Tianwei Wu,Zhenyu Du,Hao Wang
Reducing energy consumption in the desorption process of chemical absorption-based carbon capture is crucial for achieving efficient industrial-scale post-combustion carbon capture. Despite advancements in solvent improvement, catalyst application, and process optimization, there remains a significant gap between the energy consumption level and its theoretical limit. This study proposed an innovative surface treatment-seeding-hydrothermal synthesis method for loading ZSM-5 zeolite acidic catalysts onto the surface of industrial packing to enhance both the reaction kinetics and mass transfer during desorption, thereby reducing desorption energy consumption. The effectiveness of the loaded catalyst was verified in the temperature range of 86–106 °C, showing 7.84 %-37.25 % improvement in desorption amounts compared to commercial catalysts of equal volume. The optimal synthesis parameters for the loading process were investigated using various characterization techniques. It was observed that controlling the synthesis time and the number of layers to induce surface roughness, in conjunction with utilizing gels with a higher silica-to-alumina ratio, significantly enhanced the desorption performance of the supported catalytic packings based on the optimized parameters, supported catalytic packings prepared with industrial packings were tested in a simulated cyclic desorption tower. The results showed that, compared to the blank packing, desorption amounts increased by 24.30 %, 78.57 %, and 53.50 %, while relative energy consumption decreased by 19.66 %, 44.03 %, and 35.57 %, respectively.
研究领域:
化学工程
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ChemCatChem
·
2021
·Vol. 13
·期 13
·3027-3036
·
IF 5.686
Zhijian Wan,Youkun Tao,Hengzhi You,Xiang Zhang,Jing Shao
Graphical Ammonia decomposition : Ni nanoparticles with a mean size of ∼2.3 nm anchored on Na-ZSM-5 nanocrystals were prepared as a catalyst to effectively crack ammonia for CO x -free H 2 production. Ammonia has been increasingly recognised as an effective hydrogen carrier to produce clean hydrogen free of CO x emissions. This study reports the development of Ni-based catalysts to efficiently crack ammonia into hydrogen and nitrogen. A series of catalysts with different Ni loadings supported on Na-ZSM-5 zeolite nanocrystals were prepared with the assistance of 1,10-phenanthroline ligand. The coordination of Ni and the ligand led to the formation of uniform Ni nanoparticles with a mean size of ∼2.3 nm. These small Ni nanoparticles of the catalyst enabled a high activity in ammonia decomposition evaluated using a fixed-bed reactor. Using the zeolite support in its pristine sodium form provided the catalyst with desired basicity. This promotes a strong metal-support interaction, leading the catalyst to have high stability. The catalyst with 5 wt% Ni loading exhibited a high TOF of 3.51 s −1 with no performance degradation at 650 °C for 50 h.
研究领域:
材料科学
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催化化学
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能源化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2021
·
IF 4.311
Tingting Qi,Yingying Kang,Moses Arowo,Yong Luo,Guang-Wen Chu,Liangliang Zhang,Hai-Kui Zou,Baochang Sun,Jian-Feng Chen
In this study, hierarchical ZSM-5 zeolites are hydrothermally prepared using rotating packed bed (RPB) in premixing process (gelation stage). The impact mechanisms of RPB on the zeolite growth process are investigated. It is found that the zeolite precursor obtained by RPB contains abundant bubbles, and aluminosilicate aggregates in the precursor are broken and dispersed uniformly, which is beneficial for the uniform and fast growth of zeolite. Additionally, the effects of various RPB-premix process parameters, including rotation speed, premixing time, and liquid feed rate on the particle sizes of ZSM-5 are systematically investigated. The prepared ZSM-5 zeolites by RPB-premix route exhibit smaller particle sizes, narrower particle size distributions, larger specific surface areas, richer pore structure, and more acid amount compared with those by traditional premix treatment. Therefore, this study provides a novel approach for the synthesis of high-performance ZSM-5 zeolites.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2020
·
IF 7.632
Wen Li,Kuncan Wang,Guowu Zhan,Jiale Huang,Qingbiao Li
The chemical transformation of CO2 to value-added chemicals and fuels remains a daunting research challenge, requiring the development of more efficient catalysts. The present work offers highly active integrated nanocatalysts for CO2 hydrogenation to dimethyl ether (DME) through tandem catalysis, that is, Pd/ZnO converts CO2 to methanol, and bio-ZSM-5 further catalyzes methanol dehydration to DME. Notably, the hierarchically porous bio-ZSM-5 with high pore connectivity was prepared by using low-cost rice husk and luffa sponge as biotemplates. The formation of bio-ZSM-5 involved three consecutive steps, including (i) diffusion of precursor species, (ii) confined crystal growth, and (iii) calcination treatment to remove the residual biomass. Interestingly, the obtained bio-ZSM-5 possesses abundant hierarchical porosity, including the intrinsic micropores from ZSM-5 frameworks, the mesopores from intracrystalline void space or pinholes in the intergrown zeolite layers, and the macroscopic channels from the original biomass architecture. It was found that the tetrapropylammonium hydroxide amount and Si/Al ratio were two critical factors affecting the crystallinity and porosity of the bio-ZSM-5. The silicon content in biomass (8.3 wt % in rice husk and 0.016 wt % in luffa sponge) also played a crucial role in the synthesis of bio-ZSM-5. Different spatial configurations of Pd/ZnO and bio-ZSM-5 significantly affected the DME yield, wherein spatial distances between the bio-ZSM-5 and Pd/ZnO components were adjusted by controlling the size of Pd/ZnO or the integration manners. The current results indicated that the closest proximity of the bifunctional catalyst was unfavorable for DME production (selectivity < 3%), because of which low-valent Zn cations from Pd/ZnO could displace the Brønsted acid sites on bio-ZSM-5 by ion exchange, and the powder mixing in the mortar was the best combination configuration of Pd/ZnO and bio-ZSM-5, promoting the CO2 conversion (10.8%) with a DME selectivity of 31% under the reaction of 300 °C and 30 bar. Furthermore, as compared to the traditional ZSM-5 based catalyst, the obtained Pd/ZnO/bio-ZSM-5 bifunctional catalysts showed excellent long-term stability in 60 h on stream with a less amount of coke formed in the spent catalysts.
研究领域:
催化化学
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材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2021
·
IF 3.171
Xiao Zhao,Xuan Shi,Zhongshun Chen,Long Xu,Chengyi Dai,Yazhou Zhang,Xinwen Guo,Dongyuan Yang,Xiaoxun Ma
A series of ZnO-ZrO 2 solid solutions with different Zn contents were synthesized by the urea co-precipitation method, which were coupled with H-ZSM-5 zeolite to form bifunctional catalysts. As a new benzene alkylation reagent, syngas was used instead of methanol to realize the efficient conversion of syngas and benzene into toluene and xylene. A suitable ratio of ZnO-ZrO 2 led to the significant improvement in the catalytic performance, and a suitable amount of acid helped to increase the selectivity of toluene/xylene and reduce the selectivity of the by-products ethylbenzene and C 9 + aromatics. The highest benzene conversion of 89.2% and toluene/xylene selectivity of 88.7% were achieved over 10% ZnO-ZrO 2 &H-ZSM-5 (Si/Al = 23) at a pressure of 3 MPa and a temperature of 450 °C. In addition, the effect of the zeolite framework structure on product distribution was examined. Similar to the molecular dynamics of aromatic hydrocarbons , H-ZSM-5 zeolites comprise 10-membered-ring pores, which are beneficial to the activation of benzene; hence, the conversion of benzene is higher. H-ZSM-35 and H-MOR zeolites exhibited small eight-membered-ring channels, which were not conducive to the passage of benzene; hence, the by-product ethylbenzene exhibits a higher selectivity. The distance between the active centers of the bifunctional catalysts was the main factor affecting the catalytic performance, and the powder mixing method was more conducive to the conversion of syngas and benzene.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2022
·
IF 5.876
Kongyan Yang,Feng Zhou,Huixia Ma,Chuntao Liu,Fangwei Ma,Guang Wu
A series of nanocrystalline ZSM-5 zeolites with abundant intercrystalline mesopores was fabricated by a hydrothermal crystallization method without any mesopore template. The ZSM-5 zeolite was characterized by XRD , XRF , N 2 adsorption, NMR, SEM, TEM and NH 3 -TPD and used for the catalytic fast pyrolysis (CFP) of cellulose . The external surface area of the nanocrystalline ZSM-5 zeolite reached 146.6 m 2 /g, larger than the external surface area of conventional ZSM-5 (57.9 m 2 /g). The product yields of the CFP reaction were studied over different Si/Al ratios of nanocrystalline ZSM-5, and the aromatic yield of nanocrystalline ZSM-5 was generally higher than the aromatic yield of conventional ZSM-5. The relationship between the surface area, acid amounts and product yields was established by drawing a linear fitting curve. The results show that both pore structure and acidity have important effects on aromatic yield and coke yield. Aromatics are generated in micropores, and the increase in external surface area caused by reducing the particle size improves the pyrolysis of cellulose to generate bio-oil vapours, which further diffuse into micropores to generate aromatics.
研究领域:
化学工程
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）