MICROPOROUS AND MESOPOROUS MATERIALS
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2022
·
IF 5.876
Xiuli Shao,Siqi Wang,Youhui Zhou,Xuan Zhang,Haizhou Tian,Zheng Wang,Zhong-Yong Yuan,Huanting Wang
The ZSM-5 zeolite nanosheets are highly desired materials for catalytic reactions and membrane separation . Their synthesis depends on specially designed complex surfactants ; however, the high-cost limits their large-scale industrial production. Herein, the tailored synthesis of coffin-shaped multilamellar ZSM-5 composed of orderly stacked 2D nanosheets is carried out using cetyltrimethylammonium bromide (CTAB) as a structure-directing agent (SDA) in the presence of silicalite-1 seed sol. The morphology and b -axis thickness of nanosheets is controlled by adjusting the amount of silicalite-1 seed sol, CTAB/TEOS ratio, SiO 2 /Al 2 O 3 ratio, and synthesis time. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis indicate that the hydrophobic tail of CTAB acts as an inhibitor, effectively preventing the continuous growth along b -direction with an average thickness of 20–100 nm. This work highlights the role of silicalite-1 seed sol and CTAB in the orderly stacked sheets growth process. This crystallization strategy opens a facile and inexpensive approach for multilamellar ZSM-5 zeolite fabrication with 2D-nanosheets structures, and their practical applications in catalytic conversions of bulky molecules.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
Catalysis Science & Technology
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2018
·Vol. 9
·期 3
·659-671
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IF 5.365
Yanliang Zhai,Shaolong Zhang,Yunshan Shang,Yu Song,Wenxuan Wang,Tong Ma,Luoming Zhang,Yanjun Gong,Jun Xu,Feng Deng
Herein, a specific core–shell MFI zeolite was designed for the methanol to propylene (MTP) reaction. The core–shell structure of Al-ZSM-5@B-ZSM-5 and Al-ZSM-5@silicalite-1 were easily obtained via a two-step procedure, in which Al-ZSM-5 aggregate acted as the core and B-ZSM-5 or silicalite-1 as the shell. Their core–shell structures, acidity distribution and pore properties were characterized systemically, and new insights were gained into the synergetic effect of acid property and diffusion on the MTP reaction. The Al-ZSM-5@B-ZSM-5 zeolite exhibited a superior catalytic performance with a lifetime of 350 h (WHSV = 3 h−1), propylene selectivity of 49% and high turnover number of 4.3 × 106, while for the Al-ZSM-5 core, the corresponding values were 210 h, 43% and 5.2 × 105, respectively. Al-ZSM-5@silicalite-1 displayed the second best performance with the values of 250 h, 45% and 2.9 × 106, respectively. Gradient strong acid reduction from the core to the shell via the epitaxial growth of the silicalite-1 or B-ZSM-5 shell combined with an appropriate strong/weak acid ratio plays a vital role in inhibiting the hydrogen transfer reaction and thus gives a low consumption of propylene and low coke deposition. For the hydrogen transfer reaction of alkenes to form alkanes and aromatics, strong acid sites are required. Moreover, the acid sites originally existing on the external surface of the Al-ZSM-5 core were converted into internal acid sites due to the formation of an interface zone in the core–shell zeolite, possessing micropore characteristics, which in turn improve the shape selectivity and suppress coke deposition. Especially, the Al-ZSM-5@B-ZSM-5 zeolite displayed more weak acid sites and few strong acid sites on its shell surface, which are beneficial for the low formation of external coke and also account for the highest utilization of acid sites in the MTP reaction, high propylene selectivity and long lifetime.
研究领域:
催化
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化学工程
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材料科学
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产品关联
DOI
高影响因子
FUEL
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2016
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IF 3.611
Dongjing Liu,Weiguo Zhou,Jiang Wu
The high-temperature H 2 S removal was conducted over x La y Cu/ZSM-5 sorbents prepared via citric acid method. The sorbents showed good desulphurization performance, the maximal sulfur capacity of 2240.5 μmol S/g over 5La5Cu/ZSM-5 was achieved at 700 °C. The presence of H 2 obviously shortened the breakthrough time and reduced the sulfur capacity. However, the presence of CO had little influence on the desulphurization behavior. The sulfidation activity of La 2 O 3 can be significantly enhanced by introduction of Cu due to the intimate mixing of La 2 O 3 and CuO, the formation of La 2 CuO 4 compound.
研究领域:
材料科学
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环境化学
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能源工程
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催化化学
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
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2015
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IF 2.352
Xiaodong Wang,Xiaoxia Gao,Mei Dong,Hongbin Zhao,Wei Huang
Nano hierarchical mesoporous ZSM-5 catalysts were prepared with cationic dimethyldiallyl ammonium chloride acrylamide copolymer (PDDA) as a soft second template. Using ZSM-5 catalyst as a matrix, Zn/ZSM-5 catalysts were also obtained by the wet impregnation method. The effect of the PDDA amount and Zn loadings on the properties of the catalysts, including crystallinity , morphology, textural properties, acid nature and catalytic activity in MTG reaction, was investigated by XRD , FESEM , TEM, Nitrogen adsorption–desorption isotherms and NH 3 -TPD method, respectively. The MTG reaction was performed in a fixed bed reactor , and the result revealed that the nano hierarchical ZSM-5 catalyst prepared with a PDDA/Si molar ratio of 0.070 possesses longer stable phase of 70 h with a liquid hydrocarbon selectivity of 29.8%. Zn/ZSM-5 catalyst with a Zn/ZSM-5 ratio of 0.07 wt.% shows the highest liquid hydrocarbon selectivity, reaching 62.5%.
研究领域:
化学工程
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催化科学
✓ 已验证
DOI
高影响因子
Catalysts
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2020
·Vol. 10
·期 3
·311
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IF 3.52
Jing Shao,Shuyuan Cheng,Zhaoxu Li,Bichun Huang
A ZSM-5 zeolite with a hierarchical pore structure was synthesized by the desilication-recrystallization method using tetraethyl ammonium hydroxide (TEAOH) and cetyltrimethylammonium bromide (CTAB) as the desilication and structure-directing agents, respectively. The MnOx/ZSM-5 catalyst was synthesized by the ethanol dispersion method and applied for the low-temperature selective catalytic reduction of NOxwith NH3. The results showed that NOxconversion of the hierarchical MnOx/ZSM-5 catalyst could reach 100% at about 120 °C and could be maintained in the temperature range of 120–240 °C with N2selectivity over 90%. Furthermore, the hierarchical MnOx/ZSM-5catalyst presented better SO2resistance performance than the traditional catalyst in the presence of 100 ppm SO2at 120 °C. XRD, SEM, TEM, XPS, BET, NH3-TPD, and TG were applied to characterize the structural properties of the MnOx/ZSM-5 catalysts. These results showed that the MnOx/ZSM-5 catalyst had micropores (0.78 nm) and mesopores (3.2 nm) leading to a larger specific surface area, which improved the mass transfer of reactants and products while reducing the formation of sulfates. The better catalytic performance over hierarchical MnOx/ZSM-5 catalyst could be attributed to the higher concentration of Mn4+and chemisorbed oxygen species and higher surface acidity. The improved SO2resistance was related to the catalyst’s hierarchical pore structure.Keywords:hierarchical pore structure;MnOx/ZSM-5;NH3-SCR;SO2resistance
研究领域:
环境科学
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催化材料
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2019
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IF 3.375
Siqian Zhang,Cheng Zhang,Qiang Wang,Wha-Seung Ahn
A series of ZSM-5 catalysts were synthesized using fly ash from power plants and red mud from aluminum production in different weight ratios. The ZSM-5 was subsequently coimpregnated with Co and Mn and tested for the low-temperature selective catalytic reduction of NOx by NH3 (NH3-SCR). These catalysts were characterized by XRD, N2-adsorption isotherms, SEM, XPS, and H2-TPR. Among all the prepared catalysts, 5 wt % Co 10 wt % Mn/ZSM-5 had shown the best catalytic activity, with 98.8% conversion of NOx and 90.7% selectivity toward N2 at 150 °C. This is comparable to the performance of a similar ZSM-5 catalyst prepared using chemical reagents. The high ratio of Mn4+/(Mn4+ + Mn3+ + Mn2+) in the catalyst improved the NOx conversion, whereas the moderate redox property imparted by Co3+ led to high N2 selectivity. This catalyst also showed strong resistance against poisoning in 100 ppm SO2 and 5% H2O. This work demonstrates that effective NOx removal treatment with high N2 selectivity and sufficient stability for either cement plants or incinerators can be achieved by using a porous catalyst/support material produced from industrial solid wastes.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMISTRY OF MATERIALS
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2025
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IF 7
Jiaxing Zhang,Ajuan Zhou,Fang Hao,Kexin Yang,Yiren Yu,Yucai Qin,Xiongfu Zhang,Limin Ren,Anfeng Zhang,Guanghui Zhang,Chunshan Song,Xinwen Guo
The green synthesis of b-axis-oriented ZSM-5 nanosheets (NSs) is essential for facilitating their industrial production. Here, a set of cost-effective and eco-friendly additives is introduced for the tailored synthesis of thin ZSM-5 NSs with a b-axis thickness of 40 nm with the assistance of small seeds. Through a comprehensive exploration of synthesis methods and electron microscopy analysis, this work elucidates the pivotal roles of seeds and additives in controlling the crystal size and steering anisotropic growth kinetics during the crystallization process. The shortened straight channels of the thin ZSM-5 NSs along the b-axis significantly enhance the rapid transport of molecules within the micropores, thus manifesting a distinct catalytic advantage in the alkylation of benzene with methanol and methanol-to-propylene (MTP) conversion. Notably, the utilization of fluorine-free additives in the synthesis of thin ZSM-5 NSs marks an important step forward in zeolite materials, bridging the gap between laboratory experimentation and industrial scale-up.
研究领域:
材料科学
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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
Nanomaterials
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2025
·Vol. 15
·期 9
·639
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IF 4.3
Mingbo Guo,Yijun Wang,Lei Zhang,Junran Lu,Chang Gong,Wanning Zhang,Yuxi Fang,Xinyuan Zhu,Shunai Che
Zeolite is increasingly recognized for its enhancement of low-frequency acoustic performance in microspeakers. The aging characteristics of zeolite have been regarded as the critical factor for the commercial viability of mobile phones products, but the mechanism remains ambiguous. Here, the low-frequency acoustic performance of hierarchically structured ZSM-5 was investigated through aging with water and acetic acid (AA). It was discovered that water vapor augmented the resonance offset as it enhanced the structure of the zeolite, resulting in a lower water content. The resonance offset of ZSM-5 significantly decreased after the adsorption of AA vapor, as excessive AA was adsorbed through both physical and chemical adsorption, causing partial destruction of supermicropore and mesopores. The performance of ZMS-5 stored with vapor of AA and water mixture did not significantly deteriorate, indicating that water effectively protected the pores of zeolite to prevent excessive adsorption of AA. This was attributed to the fact that water was adsorbed by Brønsted acid sites of ZSM-5 more preferentially than AA, thereby avoiding excessive adsorption of AA.
研究领域:
材料科学
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声学工程
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产品关联
DOI
PubMed
高影响因子
SOLID STATE SCIENCES
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2017
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IF 1.811
Yisong Wang,Tao Du,Yanli Song,Shuai Che,Xin Fang,Lifeng Zhou
ZSM-5 type zeolite with mesoporous structure was prepared and then amine-functionalized with tetraethylenepentamine (TEPA) by wet impregnation method to form a series of CO 2 adsorbents (ZTx). The structural properties of ZSM-5 and ZTx were characterized by XRD , FTIR , TGA/DTG, nitrogen adsorption/desorption, SEM and EDX techniques. The adsorption capacity of the adsorbents with different amine loading was measured at a temperature from 40 to 100 °C and the adsorption capacity of ZT7 was 1.80 mmol/g at 100 °C. The adsorption process and mechanism were studied by fitting the experimental data used the three adsorption kinetic models, and a complex physical and chemical mixing process was produced as the amine entered the surface and pore size of the zeolite. The high adsorption selectivity at 10% CO 2 concentration and the stability of the five adsorption desorption cycles indicated that ZT7 is a suitable and promising CO 2 adsorbent for the purification of 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
CHEMICAL ENGINEERING JOURNAL
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2025
·
IF 13.2
Yibo Tang,Jiayin Liang,Jiabing Chen,Mengheng Wang,Xinying Liu,Xiaojun Lu
Na- and Mn-promoted Co 2 C-based catalysts have demonstrated promise for the one-step conversion of syngas to olefins via Fischer-Tropsch synthesis to olefins (FTO). However, their consistently low activity limits their industrial applications. Here, we designed a compound catalyst comprising a CoMn composite catalyst and ZSM-5 zeolite, achieving 4.9 times the activity compared to the sole Co 2 C catalyst without compromising olefin selectivity. CO– and H 2 -TPD studies, in-situ DRIFT experiment, and DFT calculation revealed that the surface acidity of ZSM-5 modulated the strong electron effect of Na, subsequently strengthening H 2 adsorption on the Co 2 C catalyst surface. The H-assisted CO dissociation was therefore promoted and the catalyst activity was boosted. Meanwhile, Co 2 C as active site was unaffected, maintaining high selectivity to olefins. Constructing an interface between Co 2 C and ZSM-5 in the compound catalyst is proven to be a successful strategy for enhancing the activity of Co 2 C-based catalysts for FTO.
研究领域:
催化化学
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材料科学
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能源化学
✓ 已验证
产品关联
DOI
高影响因子
NANO
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2024
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IF 1
Xuecong Ma,Linlin Geng,Yu Li,Jianwen Wei,Lei Liao,Dunqiu Wang
Micro/mesoporous materials are low-cost functional materials with the potential for CO 2 adsorption. Modifying micro/mesoporous materials is significant for enhancing CO 2 adsorption and their high-value utilization. Herein, the micro/mesoporous material of composite molecular sieve ZSM-5/MCM-48 (ZM) was synthesized by a two-step crystallization method using cetyltrimethylammonium bromide as a template, tetraethyl orthosilicate as a silicon source and ZSM-5 seed as part of silicon aluminum source. Tetraethylenepentamine (TEPA) and polyethyleneimine (PEI) were used as impregnation modifiers to modify ZM with amine groups. The results showed that with the increase of amine loadings, both ZM-T60 (Impregnated with TEPA) and ZM-P60 (Impregnated with PEI) functionalized adsorbents exhibited the best adsorption capacities of 4 . 9 7 mmol ⋅ g − 1 and 3 . 2 8 mmol ⋅ g − 1 at 60, respectively, when the loading of ZM sample was 60%. The adsorption kinetic analysis showed that the adsorption of CO 2 by ZM-T60 and ZM-P60 was a chemisorption-dominated process accompanied by physical adsorption. After 10 adsorption/desorption cycles, the CO 2 adsorption capacity of ZM-T60 and ZM-P60 decreased by 8.7% and 2.6%, respectively. This work demonstrates that impregnation modification of the composite molecular sieve to achieve efficient CO 2 adsorption has practical application significance.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
DOI
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2022
·Vol. 38
·期 4
·1083-1088
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IF 2.726
Xiao Peiwen,Li Hui,Wang Pingmei,Liu Bolun,Jing Wendan,He Lipeng,Wang Runwei,Han Xue,Zhang Zongtao,Qiu Shilun,Luo Jianhui
Herein, we propose a novel approach to reduce the viscosity of heavy oil by functional hierarchical CTMS-ZSM-5-PTMS zeolites. CTMS-ZSM-5-PTMS zeolites synthesized by asymmetric modification and selective alkali etching can reduce the viscosity of heavy oil through adsorbing asphaltenes. This method can reduce the viscosity of heavy oil from hundreds of thousands mPa·s to about ten thousand mPa·s. The work provides an economical and environmentally friendly candidate for heavy oil viscosity reduction under low-temperature conditions.
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
危险品化学品经营许可证（带存储）