CATALYSIS COMMUNICATIONS
·
2018
·
IF 3.463
Qinqin Wang,Mingyuan Zhu,Haiyang Zhang,Caixia Xu,Bin Dai,Jinli Zhang
Zr-modified ZSM-5 zeolite was successfully prepared, and Zn/Zr-ZSM-5 was employed as a catalyst for the acetylene hydration reaction. High catalytic activity, above 96% C 2 H 2 conversion, was achieved at 260 °C with a feed reactant ratio of H 2 O/C 2 H 4 = 4 and a GHSV of 90 h −1 . To understand the influence of zirconium addition in the zeolite, Fourier-transform infrared spectroscopy, X-ray diffraction, surface texture analysis (BET method), transmission electron microscopy, temperature programmed desorption of NH 3 , temperature programmed reduction by hydrogen and X-ray photoelectron spectroscopy techniques were used. The incorporation of zirconium in the zeolite enhanced Zn metal dispersion and metal–support interactions. Moreover, an enhanced concentration of weak acid sites and active catalytic sites were found to be responsible for the high catalytic activity of Zn/Zr-ZSM-5 for the acetylene hydration.
研究领域:
催化化学
·
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
Haochen Qi,Chuang Xing,Weiguo Huang,Mingquan Li,Yujia Jiang,Xu Sun,Heyang Liu,Peng Lu,Jiangang Chen,Shuyao Chen
Fischer-Tropsch (FT) synthesis as a strongly exothermic reaction has diffusely manufactured clean fuels from syngas. However, it is difficult to obtain the concentrated product distributions. Here, we design ZSM-5 encapsulated cobalt particles on the thermal conductivity of the SiC matrix. The Co@NaZSM-5/SiC capsule catalyst with hierarchical structure is ingeniously assembled through a solvent-free synthesis route. Due to the joint functions of acidic zeolite , SiC thermal conductivity and macropores, the olefin selectivity enhances to 32.3% on the Co@NaZSM-5/SiC catalyst. Moreover, the ratio of O 5-11 /C 5-11 approaches 49.1% suggesting the elevated middle olefin proportion. The H + ion-exchanged Co@HZSM-5/SiC capsule catalyst shows a high isoparaffin selectivity of 27.3%, since the olefin isomerization reaction is accelerated over strong acid sites. Besides, Co 2 C phase is readily formed during the FT reaction, which is an activity center for olefin synthesis. The capsule catalyst with the proper acidity, thermal conductivity, and hierarchical structure is a promising prospect for tuning production distribution in FT reaction.
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
ChemCatChem
·
2018
·Vol. 10
·期 24
·5619-5626
·
IF 4.674
Xing Yu,Cunhui Zhou,Xinqing Chen,Peng Gao,Minghuang Qiu,Wenjie Xue,Chengguang Yang,Hanqin Zhao,Hongjiang Liu,Ziyu Liu,Yuhan Sun
Graphical CatalyZSM-5 : Well crystallized hollow fibers assembled by c -axis oriented ZSM-5 crystals were successfully synthesized via a facile one-pot solvent-free route, using quartz fiber as silicon substrate and NH 4 HCO 3 as the growing inhibitor on the crystal faces. The obtained ZSM-5 hollow fibers gave a hierarchical structures composed by micro-, meso- and macropores exhibiting excellent performance in methanol to gasoline (MTG) reaction with higher C 5+ selectivity and longer lifetime due to the improved mass transfer inside the unique hollow fiber structure. Well crystallized hollow fibers assembled by c -axis oriented ZSM-5 crystals were successfully synthesized via a facile one-pot solvent-free route, using quartz fiber as silicon substrate and NH 4 HCO 3 as the growing inhibitor on the crystal faces. The immigration of silica inside the quartz fibers formed the hollow morphology and the shell of hollow fiber was composed by the ZSM-5 crystals. In addition, the length of c -axis of ZSM-5 could be controlled by the amount of NH 4 HCO 3 , which selectively inhibited the growth on (010) surface. The obtained ZSM-5 hollow fibers gave a hierarchical structures composed by micro-, meso- and macropores. Catalytic tests for methanol to gasoline (MTG) revealed that the resultant ZSM-5 hollow fiber exhibited excellent performance with higher C 5+ selectivity and longer lifetime due to the improved mass transfer inside the unique hollow fiber structure.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2020
·Vol. 22
·期 5
·1630-1638
·
IF 9.48
Bin Zhang,Mark Douthwaite,Qiang Liu,Chao Zhang,Qifan Wu,Ruhui Shi,Peixuan Wu,Ke Liu,Zhuangqing Wang,Weiwei Lin,Haiyang Cheng,Ding Ma,Fengyu Zhao,Graham J. Hutchings
A novel method for the synthesis of MFI zeolites has been developed, which does not require any crystal seeds or solvent. The adaptability of this method was also evidenced; a series of ZSM-5 zeolites with differing Si/Al ratios (18∼∞) were synthesized, which to date, has been a challenge in the field of solvent-free synthesis. The materials were probed by in situ DRIFTS and 2D 27Al–19F HETCOR NMR spectroscopy, the results from which indicated that fluorine-containing species play a crucial role in the crystallization of ZSM-5. During the crystallization process F− anions coordinate with Al3+ cations, resulting in the formation of 6-coordinated “F–Al–O–Si” species. It is these intermediate species which drive the formation of tetrahedral [AlO4]− units in the zeolitic framework. The effectiveness of these materials as catalyst supports was subsequently assessed in the hydrogenation of levulinic acid and glucose, which exhibited a comparable performance to commercial ZSM-5. The simple, efficient and low-cost method presented herein provides an alternative approach for the green scaled-up synthesis of zeolites.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2019
·
IF 14.229
Jiaqin He,Dongyun Chen,Najun Li,Qingfeng Xu,Hua Li,Jinghui He,Jianmei Lu
Mesoporous ZSM-5 zeolite-supported PdCu alloy nanoparticle catalysts are synthesized via a facile and environmentally friendly method. The mesoporous structure is formed through the loss of carbon black particles encapsulated by zeolite crystals during calcination. The ZSM-5-supported PdCu nanoparticles are shown to possess mesoporous structure, evenly distributed PdCu alloy nanoparticles, and excellent catalytic performance in toluene oxidation. The mesoporous structure of the ZSM-5-supported PdCu nanoparticles provides a large specific surface area and pore size, resulting in numerous accessible active sites. The alloying of Pd with Cu both increases the catalytic performance of the catalyst and lowers its cost. Overall, the catalyst with a Pd/Cu ratio of 8:2 showed the highest catalytic activity of the fabricated materials, achieving 100 % toluene conversion at 160 °C. The mechanism of toluene oxidation over these catalysts can be explained by the Mars–van Krevelen model.
研究领域:
催化化学
·
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
Huijie Xie,Wei Xu,Saiai Ran,Xiaolong Li,Bin Li,Yanyan Li,Lei Wang
Green synthesis of zeolite has been made much progress due to solvent-free grinding methods. Although solid-state synthesis is a simple green process with a high yield, its kinetics of the solid-phase crystallization process is still slow and the precursor materials are not uniformly heated throughout the reactor resulting into the poor uniformity of the particles. Herein, we report a high-efficiency organotemplate-free synthesis of ZSM-5 combining solid state grinding and steam-assisted crystallization. Solid state grinding (SSG) of aluminosilicate precursor avoids usage of solvent and steam-assisted conversion (SAC) in an organic-template-free condition grants a fast crystallization rate of ZSM-5. More importantly, the vapor fulfilled in the reactor ensures uniform heating of solid feedstock for crystallization of ZSM-5, leading the high crystallinity and the uniform particle size distribution . This combination can guarantee 100% relative crystallinity of ZSM-5 in 12 h, compared to that of 80% crystallinity from sole solid state at the same crystallization temperature (180 °C). Furthermore, this combination can achieve 83% relative crystallinity of ZSM-5 at 160 °C, compared to that of 37% crystallinity from the solid state alone. Highly dispersed ZSM-5 zeolite with adjustable SiO 2 /Al 2 O 3 ratio is prepared by steam-assisted crystallization of grinding solid raw materials. The catalytic activity of ZSM-5 catalyst from this combination strategy for the acetalization of cyclohexanone is superior to that of the solid-state method alone. This sustainable and green synthesis method provides a potential way for the preparation of zeolites in an industrial scale.
研究领域:
材料科学
·
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2017
·
IF 3.471
Yunwu Zheng,Fei Wang,Xiaoqin Yang,Yuanbo Huang,Can Liu,Zhifeng Zheng,Jiyou Gu
The main objective of this work was to study aromatics production via the catalytic pyrolysis upgrading of biomass using metal-loaded modified H-ZSM-5. M-ZSM-5 catalysts were prepared through the impregnation method with Zn, Ga, Ni, Co, Mg and Cu. The prepared M-ZSM-5 catalysts were evaluated by x-ray diffraction, thermal desorption spectroscopy and scanning electron microscopy. The properties, composition and product distribution of bio-oil were also analysed. Results showed that the M-ZSM-5 catalysts yielded a higher amount of non-condensable gas at the expense of the liquid yields. The Ga-ZSM-5 catalysts produced the highest yields of bio-oil (25.76 wt%), but the lowest amount of coke (22.08 wt%) compared with the unmodified ZSM-5 catalyst (33.38 wt%). The content of the single-ring aromatics prepared by using the Zn-ZSM-5 catalysts was the highest at 90.28 wt%, whereas that of the polycyclic aromatic hydrocarbon prepared by the Ni-ZSM-5 catalysts was the highest at 31.36 wt%. Moreover, the selectivity of the single-ring aromatic hydrocarbons, such as C7 and C8, were significantly affected by the use of the M-ZSM-5 catalysts. The Zn-ZSM-5 catalysts were the most selective for toluene and xylenes with contents of 36.52 wt% and 35.32 wt%, respectively, whereas the Co-based catalysts were the most selective for indene. The Ni-based catalysts can obviously improve the selectivities of benzene production and C10+ polycyclic aromatic hydrocarbons. Zn-ZSM-5 was the most effective catalyst that can be used in the production of aromatic hydrocarbons.
研究领域:
能源化学
·
催化材料科学
✓ 已验证
DOI
高影响因子
FUEL
·
2024
·
IF 6.7
Zekun Guan,Guangxun Sun,Chao Feng,Junxi Li,Minmin Wang,Mengdi Guo,Bin Liu,Yuan Pan,Chenguang Liu,Yongming Chai,Yunqi Liu
The production of cleaner gasoline requires reducing sulfur and olefin content in fluid catalytic cracking (FCC) gasoline. Herein, Ni/ZSM-5@Ni/ZnO catalysts were synthesized by uniformly coating Ni/ZnO on the surface of Ni/ZSM-5 by electrostatic induced crystallization strategy for FCC gasoline desulfurization-aromatization tandem reactions. The desulfurization activity of Ni/ZSM-5@Ni/ZnO has superior desulfurization activity due to the smaller size of ZnO, higher O vacancy content, and more uniform dispersion of Ni and ZnO relative to the physically mixed Ni/ZSM-5-Ni/ZnO. In addition, coating Ni/ZnO on the surface of Ni/ZSM-5 can reduce the Brønsted acid content of Ni/ZSM-5, increase the Lewis/Brønsted acid value of the catalyst, which inhibits the excessive cracking of FCC gasoline, and improves the liquid yield and aromatics selectivity. After 8 h of reaction, the desulfurization rate, aromatics generation rate and olefin conversion rate of Ni/ZSM-5@Ni/ZnO were 85.58 %, 25.22 % and 49.08 % respectively, which were higher than those of physically mixed Ni/ZSM-5-Ni/ZnO catalysts by 25.34 %, 15.95, and 12.98 %, respectively. Meanwhile, the unique structure of Ni/ZSM-5@Ni/ZnO reduces carbon deposition and delays catalyst deactivation. Density functional theory calculations show that Ni/ZSM-5@Ni/ZnO was more favorable for thiophene desulfurization and has a better ability to adsorb and activate H 2 . This study provides a new idea for the development of catalysts for clean gasoline production.
研究领域:
催化化学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2025
·
IF 7.5
Yan Tan,Xiao Liu,Yujia Zhang,Yiyang Rong,Xueying Wu,Ting Liu,Zizhen Ma,Huawei Zhang
In the current study, catalytic oxidation technology is among the most widely used methods for removing chlorinated volatile organic compounds (CVOCs). This article details the preparation of the Ag-Mn@ZSM-5 catalyst, which was prepared via the hydrothermal approach, followed by the incorporation of nano-Ag. The focus of the study is the catalytic oxidation of chlorobenzene (CB). Experimental results indicate that the hydrothermally synthesized nano-silver modified Ag-Mn@ZSM-5 catalyst, exhibiting a T90 of 290 °C, demonstrates superior performance compared to the Ag-Mn/ZSM-5 catalyst prepared via the traditional impregnation method, which has a T90 of 365 °C. As the operating airspeed increased from 7000 h −1 to 42000 h −1 , the removal efficiency of CB consistently remained above 90%, with stability maintained over a duration of 30 h. Furthermore, the catalyst exhibited excellent water resistance during a 12 h switching water test. Based on the characterization results, after loading Ag, the ratio of Mn 4+ and Mn 3+ on the surface of the Ag-Mn@ZSM-5 catalyst increases, the reducibility is enhanced, and the surface adsorbed oxygen species is increased, which is conducive to improving the catalytic activity. In addition, the Ag-Mn@ZSM-5 catalyst possesses an optimal pore structure, the proportion of mesoporous is 79.06%, suitable redox capacity, abundant acidic sites, and features a compact crystal stacking structure, which results in remarkable stability, catalytic activity, and space velocity resistance of the catalyst. These advantageous properties facilitate the adsorption and deep oxidation of CB. This study presents promising prospects for industrial applications and aims to offer innovative strategies for the treatment of chlorine-containing waste gases.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2020
·
IF 4.551
Tingting Qi,Jing Shi,Xishuo Wang,Kun Dong,Yong Luo,Jiawei Teng,Guang-Wen Chu,Hai-Kui Zou,Baochang Sun
Hierarchical (micro/mesopore) ZSM-5 zeolites were hydrothermally synthesized in a rotating packed bed (RPB) which substantially enhances micromixing for the high viscosity reaction system. Herein, the effects of four operating processes with different micromixing intensity on nucleation/crystal growth process as well as physicochemical properties of ZSM-5 zeolites were investigated. Results indicate that enhancing micromixing by RPB in the zeolite synthesis could facilitate the formation of Al sites and shorten the nucleation and crystallization period. ZSM-5 samples prepared by RPB exhibit hierarchical structure, smaller average particle size, more uniform particle size distributions , larger specific surface areas, higher catalytic stability as well as more acid sites than those obtained by (stirring tank reactor) STR. While adopting the ZSM-5 samples prepared by RPB for catalyzing C4-olefin cracking reaction, the conversion of C4-olefin and yield of propylene are higher than those obtained by STR.
研究领域:
材料科学
·
化学工程
·
催化反应
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2015
·
IF 9.312
Liang Wang,Jian Zhang,Xianfeng Yi,Anmin Zheng,Feng Deng,Chunyu Chen,Yanyan Ji,Fujian Liu,Xiangju Meng,Feng-Shou Xiao
Zeolite-based catalysts have been widely used in the conversion of biomass recently, but the catalytic yields of the desired products are strongly limited by the relatively small micropores of zeolite. Here, we reported a hierarchically porous ZSM-5 zeolite with micropore and b-axis-aligned mesopore-supported Ru nanoparticles (Ru/HZSM-5-OM) that are highly efficient for the hydrodeoxygenation of both small and bulky phenolic biomolecules to the corresponding alkanes. Compared with the conventional ZSM-5 zeolite-supported Ru catalyst, the high catalytic activities and alkane selectivities over Ru/HZSM-5-OM are attributed to the abundant exposed acidic sites in HZSM-5-OM with open mesopores. This feature is potentially important for future phenolic bio-oil upgrading.
研究领域:
催化化学
·
生物质能
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL RESEARCH
·
2022
·
IF 1.097
Ying Wang,Fei Du,Chunyan Wang,Jiaqiang Zhao,Haizhu Sun,Chuanyin Sun
High-performance hierarchical cheese-like C-ZSM-5 nanocrystals are successfully prepared by acid–base treatment and are evaluated for oxidative desulfurization of dibenzothiophene. The acid–base treatment can generate a large number of Si-OH bonds and an open-mesoporous structure, which is conducive for the dispersion of TiO2 and also for the transport of dibenzothiophene and its oxidation products simultaneously. The catalytic results indicate that the hierarchical cheese-like C-ZSM-5 nanocrystals are highly active catalysts for the oxidative desulfurization of dibenzothiophene due to open mesoporosity. Complete conversion was obtained within 80 min at 338 K. The excellent performance is due to the large number of active framework sites and open mesopores generated by post-processing.
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）