FUEL
·
2025
·
IF 7.5
Guopei Zhang,Cong Wang,Xiaoyang Zhang,Yong Dong,Zhaomin Li,Leteng Lin
A novel Cu 2 LaO 4 /ZSM-5 sorbent was synthesized using the sol–gel method, and the role of H 2 S in enhancing Hg⁰ removal was investigated through experimental and theoretical approaches. Mercury removal performance was evaluated in a fixed-bed reactor under simulated syngas conditions, revealing that H 2 S significantly promoted removal efficiency, achieving 95.6 % at 200 °C. In contrast, H 2 and CO inhibited Hg 0 removal by depleting surface oxygen species. The addition of H 2 S mitigated these effects, facilitating Hg 0 adsorption and oxidation via a Langmuir–Hinshelwood mechanism. Density functional theory (DFT) calculations confirmed strong chemisorption of Hg 0 and H 2 S on the Cu 2 LaO 4 surface, with adsorption energies of −123.71 kJ/mol and −168.98 kJ/mol, respectively. The reaction to form HgS had a manageable energy barrier of 25.80 kJ/mol and an exothermic enthalpy of −196.82 kJ/mol, with HgS formation as the rate-limiting step. This study highlights the effectiveness of Cu 2 LaO 4 /ZSM-5 for mercury capture and its potential application in industrial syngas purification.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2021
·
IF 5.541
Jianjun Xiao,Minjiao Yang,Qingfeng Che,Yingquan Chen,Xu Chen,Haiping Yang,Pietro Bartocci,Francesco Fantozzi,Hanping Chen
The effect of potassium in biomass on the catalytic activity of ZSM-5 zeolite in the fast pyrolysis of biomass was investigated using 2-methylfuran (2-MF) as the typical model compound. The mechanism of action of potassium was explored in detail, along with the physicochemical properties of ZSM-5, including crystallinity, pore structure, and surface acidity. The physicochemical properties of ZSM-5 deteriorated to varying degrees after being tainted with different potassium sources (KOH, K 2 CO 3 , KAc, and KCl). Compared with neutral KCl and strong alkali KOH, K 2 CO 3 , and KAc, with weaker alkalinity but larger crystal structure, exerted a larger influence on ZSM-5. Changes in ZSM-5 tainted with K 2 CO 3 were the greatest, and crystallinity, surface area, acidity, and the corresponding yields of valuable aromatic hydrocarbons and gas products, all declined significantly, compared with raw ZSM-5. When the amount of K(CO 3 2− ) on ZSM-5 was less than 0.5 wt%, only minor (<10 %) changes were observed in crystallinity and surface area, but total acidity decreased by over 30 percent. The conversion of 2-MF was increased using ZSM-5 tainted with less than 0.5 wt% K(CO 3 2- ) and less liquid oxygenated compounds and more CO 2 were produced. Appropriate total acidity, adjusted by a tiny amount of K 2 CO 3 , could promote deoxygenation to CO 2. However, the decarbonylation reaction was inhibited, causing a negative effect on monocyclic aromatic hydrocarbons, which was attributed to the large-scale loss of both acidity and physical structure of ZSM-5 caused by more than 1.0 wt% K(CO 3 2- ).
研究领域:
化学工程
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2021
·Vol. 11
·期 35
·21235-21247
·
IF 3.361
Guang Xiong,Feifei Meng,Jiaxu Liu,Liping Liu,Leping Zhao
An innovative hydrothermal method has been successfully applied to the synthesis of hierarchical ZSM-5/beta composite zeolites with different mass ratios. Firstly, the ZSM-5 zeolites were coated with amorphous silica and aluminum species by a spray drying process. Then, the precursor powder was hydrothermally crystallized for only 1–2 days with the addition of tetraethyl ammonium hydroxide (TEAOH). The obtained products were characterized by XRD, SEM, TEM, N2 physical adsorption–desorption, 27Al MAS NMR, ICP, pyridine-IR and NH3-TPD techniques. The characterization results imply that the ZSM-5/beta composite zeolites exhibit hierarchical-pores, higher external surface areas and larger mesopore volumes as compared to those of the pure ZSM-5 and beta zeolite. Moreover, the pore structure and acid sites of the ZSM-5/beta composite can be adjusted by changing the mass ratio of ZSM-5/beta. Finally, the ZSM-5/beta composite catalysts exhibit good catalytic performances in the cracking of 1,3,5-triisopropylbenzene (1,3,5-TIPB).
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PETROLEUM SCIENCE AND TECHNOLOGY
·
2017
·
IF 0.655
Lanyu Xing,Zhenhao Wei,Zhenhao Wen,Xuedong Zhu
Hierarchical and conventional ZSM-5 zeolites were synthesized through steam-assisted crystallization approach using acid-treatment kaolin clay as the silica and aluminium sources. The samples were characterized by XRD, SEM, NH3-TPD, N2-physisorption and TG techniques. The results showed that hierarchical ZSM-5 had rich mesopores and bigger specific surface. In conversion of methanol to aromatics, hierarchical and conventional ZSM-5 zeolites showed higher selectivity for aromatics compared with commercial ZSM-5. Under the conditions of 450 °C, 0.15 MPa, the synthesized hierarchical ZSM-5 showed longest lifetime of 380 h, which was 2 and 6 times than those of conventional and commercial ZSM-5, respectively.
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
MATERIALS CHEMISTRY AND PHYSICS
·
2017
·
IF 2.084
Yisong Wang,Tao Du,Ziyang Qiu,Yanli Song,Shuai Che,Xin Fang
Mesoporous ZSM-5 zeolite as the adsorbent supporting material was synthesized from rice husk ash (RHA), and then impregnated with polyethylenimine (PEI) for amine functional modification. A series of adsorbents (ZSM-5-PEI-X) with different PEI loading ratios were characterized by XRD , FTIR , TGA/DTG, nitrogen adsorption-desorption, SEM and EDX techniques. The measurement of the adsorption capacity at different temperatures was indicated that ZSM-5-PEI-30 had the highest adsorption capacity at 120 °C (1.96 mmol/g). The experimental data were fitted by adsorption kinetic models and isotherm models, indicated that fractional-order model and the Dual-site langmuir model can be used to describe the adsorption mechanism and predict the adsorption performance. The high CO 2 adsorption selectivity and regeneration stability suggested that this adsorbent is a potential candidate in the adsorption and separation of CO 2 in industrial flue gas .
研究领域:
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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2020
·
IF 4.939
Zhaowei Li,Xiaosong Yang,Yingxiang Han,Long Rong
The conversion of biomass to produce high-valued chemical aromatic intermediates such as benzene (B), toluene (T), ethylbenzene (E), xylene (X), naphthalene (N) has attached booming interests. Herein, in order to obtain BTEXN aromatics on the hydrocracking of Jatropha oil, several LaNiMo/ZSM-5 catalysts (La loading from 0.5 to 15 wt%) by alkali treatment and metal impregnation methods were synthesized and investigated. Fundamentally, we found the alkali treatment engendered more mesoporosity to ZSM-5 and resulted in higher catalytic activity . It bears emphasis that further metal impregnated catalyst NiMo/ZSM-5 could improve the aromatics yield due to the increase of metal active sites and acidity sites. Besides, we noted that La loading had positive effects on coke reduction, catalytic stability and catalyst lifetime. To sum up, results confirmed the favorable 1 wt% La–NiMo/ZSM-5 had maximum 75 wt% BTEXN yield, longer catalyst lifetime for 100 h and decreased carbon deposits by 1.11%.
研究领域:
化学工程
·
催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 1
·49611
·
IF 2.52
Zongqi Zhang,Yuanfeng Wu,Lijing Gao,Guomin Xiao
This work aims at investigating the special application of ZSM-5/polydimethylsiloxane (PDMS) membrane being used for pervaporation separation of levulinic acid aqueous solutions. The effects of temperature, downstream pressure, feed concentration, and raw material ratio on the separation performance are investigated by self-made flat-sheet films. When the flow rate of feed pump remained at 0.4 ml/min (10 wt% levulinic acid), a levulinic acid permeation flux of 334.13 g/(m 2 h) and a separation factor of 2.382 at 75°C are observed over the composite membrane doped with 10 wt% ZSM-5. In addition, the acid resistance is enhanced after the PDMS membranes are doped with ZSM-5. Besides, the functionalized process also makes the membranes increase in its hydrophobicity. The results demonstrate that the ZSM-5/PDMS-based membranes show profound prospects for separating levulinic acid aqueous solution.
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
JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
·
2019
·Vol. 52
·期 1
·69-74
·
IF 0.627
Miao Xue,Mei-Hua Zhu,Cai-Jun Zhong,Yu-Qin Li,Na Hu,Izumi Kumakiri,Xiang Shu Chen,Hidetoshi Kita
A high performance ZSM-5 zeolite membrane is applied to remove H2O from the esterification of acetic acid and isopentanol by pervaporation. The influences of reaction conditions on the isoamyl acetate yield are studied in detail. Compared with the traditional esterification of acetic acid and isopentanol, the esterification with “membrane extractor” has a well isoamyl acetate yield at low reaction temperature. With the reaction temperature, acetic acid/isopentanol molar ratio and effective membrane surface area to esterification mixture ratio volume of 100°C, 3.0/1.0, 2.0 wt% NaHSO4, and 0.26 cm2/cm3, respectively, the isoamyl acetate yields was 98.39%, the membrane flux and separation factor (H2O to organic) were 0.21 kg·m−2·h−1 and 1040, respectively. Further, the ZSM-5 zeolite membrane shows good long–term stability and reproducibility for the pervaporation-esterification, the isoamyl acetate yields of the esterification-pervaporation for intermittent 8 times or continuous 160 h still remained at 97.73% and 98.30%, respectively. In addition, the ZSM-5 zeolite membrane still retained the typical MFI diffraction peaks and morphology by XRD and SEM characterization after long-term PV–esterification .
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS RESEARCH
·
2022
·Vol. 37
·期 2
·543-553
·
IF 2.909
Jia Yanfei,Wei Jianwen,Yuan Yuan,Geng Linlin,Chen Siqi,Liao Lei
A stable and effective amine-modified adsorbent for CO 2 capture was prepared with the impregnation method using the ZSM-5/SBA-16 (ZS) as support and the tetraethylenepentamine (TEPA) as modifier. The CO 2 adsorption performance was investigated by thermal gravimetric analysis (TGA) in mixed gases (15% CO 2 and 85% N 2 ) at 30–90 °C. At 60 °C, the ZS displayed the highest CO 2 adsorption capacity of 2.80 mmol g −1 at 60% TEPA loading. The adsorption kinetics analysis showed that the adsorption process of amine-modified ZS was dominated by both physical and chemical adsorptions. After five cycles of adsorption/desorption, ZS-T-60 kept better stability with the equilibrium adsorption capacity of the composite material was 2.486 mmol g −1 , which was 11.1% lower than the original adsorption capacity. The composite material ZS showed good CO 2 capture ability, indicating the promising future of these adsorbents for CO 2 adsorption from actual flue gas after desulfurization. Graphical abstract
研究领域:
材料科学
·
环境科学
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产品关联
DOI
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 50
·29618-29626
·
IF 3.119
Yanming Jia,Qinghua Shi,Junwen Wang,Chuanmin Ding,Kan Zhang
Hierarchical nano-ZSM-5 zeolites (Z5-X) with different grain sizes were synthesized by varying amounts of 3-glycidoxypropyltrimethoxysilane (KH-560) in the hydrothermal synthesis strategy. Moreover, the conventional ZSM-5zeolite(Z5), which was prepared without KH-560, was used as the reference sample. The crystalline phases, morphologies, porous characteristics, Si/Al molar ratios and acidic properties of all fresh catalysts were characterized using the X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR), scanning electron microscopy (SEM), N2 adsorption–desorption, inductively coupled plasma atomic emission spectroscopy (ICP) and temperature programmed desorption of ammonia (NH3-TPD) techniques. Results show that the grain size and strong acid amount of zeolite decreased with the increasing amount of KH-560. The micropore surface areas and the corresponding volume of Z5-X changed less compared with Z5. Consequently, the high shape-selectivity of zeolite was preserved well under the addition of KH-560. However, the mesopore surface areas and the corresponding volume increased significantly with the increasing amount of KH-560. Benefiting from the abundant hierarchical structure, the Z5-X catalysts exhibited a larger coke capacity than the Z5 catalyst. The coke depositions of all the deactivated catalysts were characterized by the thermogravimetric technique (TG), and the results are indicative of the decreased average rate of coke deposition with an increasing amount of KH-560, which could result from the gradually reduced strong acid amount and the nano-sized crystallites. The catalytic performance of methanol-to-aromatics (MTA) indicates that the Z5-0.12 catalyst exhibited higher catalytic activity and selectivity of BTX as the reaction was prolonged, which could result from the synergistic effect among the proper strong acid amount, the smaller zeolite grain size, and the abundant hierarchical structure.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL
·
2023
·
IF 7.4
Lin-Cong He,Hua-Hui Xu,Xing-Yue Leng,Ling-Yun Jin,Ai-Ping Jia,Meng-Fei Luo,Jian Chen
Selective catalytic oxidation of nitrogen containing volatile organic compounds (NVOCs) is very meaningful but still remains big challenge because it is very difficult to balance the oxidation activity and N 2 selectivity of available catalysts. In order to develop excellent catalysts with high N 2 selectivity in wide temperature window ( △T ) during NVOCs oxidation, CeO 2 modified CuO/ZSM-5 catalysts with different CeO 2 addition order were prepared for diethylamine (DEA) oxidation. Detailed characterizations of catalysts such as XRD, XPS, H 2 -TPR and NH 3 -TPD were conducted, it is found that addition of CeO 2 obviously changes the geometrical and electronic states of CuO active sites in the catalyst, and CeO 2 addition order affects the Ce 3+ ratio on the catalyst surface. Promotion of CeO 2 species enables the generation of more highly active Cu species (Cu + species and finely dispersed CuO clusters) for DEA oxidation; and synergistic catalysis of the Ce 3+ species, active Cu species and acid sites in ZSM-5 leads to the high N 2 selectivity in wide temperature window ( △T ). Compared to the CeO 2 /CuO/ZSM-5 and CuO-CeO 2 /ZSM-5 catalysts, the CuO/CeO 2 /ZSM-5 catalyst exhibits moderate high oxidation activity with T 99 of 230 °C and the widest △T of 150 °C for high N 2 selectivity. Our primary results in this work provide the efficient strategy for improving catalyst employed for NVOCs selective oxidation.
研究领域:
催化化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
SOLID STATE SCIENCES
·
2016
·
IF 2.041
Haoliang Xue,Zhuangzhang He,Yun Zhao,Qingze Jiao,Qin Wu,Hansheng Li
ZSM-5/KIT-1 composites were synthesized using an ionic liquid as a template. The structures and morphologies of as-obtained products were characterized using an infrared spectroscopy, X-ray diffractometer, N 2 adsorption/desorption, scanning electron microscopy and transmission electron microscopy . The resultant zeolites show a fully crystalline microporous MFI zeolite framework and a three-dimensional network of short worm-like channels. Mesopores and microspores of 4.2 and 0.8 nm in diameter coexist in the zeolite composites. Moreover, the ratio of ZSM-5 and KIT-1 could be simply adjusted by controlling the pre-crystalline time. We believe that the strategy for fabricating ZSM-5/KIT-1 through a simple method could potentially promote the large-scale production of zeolite composites.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）