ACS Sustainable Chemistry & Engineering
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2023
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IF 8.4
Changcheng Wei,Jinzhe Li,Zhongmin Liu
The utilization of renewable biomass using γ-valerolactone (GVL) as a platform is a sustainable and important route for the production of valuable chemicals. Herein, the selective transformation of GVL to 1,3-butadiene over zeolite catalysts under ambient pressure and continuous flow conditions was reported. Effects of zeolite topologies, acid density, reaction temperature, and contact time on the GVL conversion were systematically investigated. A 1,3-butadiene selectivity of 71% and GVL conversion of 100% were achieved over the NaZSM-35 catalyst at 400 °C. Further investigations revealed that the GVL-to-butadiene reaction might proceed by the following reaction route: GVL was first converted to pentenoic acid (PEA) and then dehydrated into acylium ions, further converting to 1,3-butadiene by decarbonylation. This work provided a promising route for the sustainable and selective production of 1,3-butadiene from renewable materials.
研究领域:
催化化学
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可再生资源利用
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绿色化学
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
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2022
·Vol. 24
·期 39
·6987-6995
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IF 3.756
Shujie Dai,Yangchun Tan,Yuhan Yang,Longfeng Zhu,Baogang Liu,Yanyan Du,Xuebo Cao
Organotemplate-free synthesis of zeolites assisted with zeolite seeds has been a hot topic in the past decade. Herein, we for the first time show an organotemplate-free synthesis of Al-rich S-ZSM-35 and S-ZSM-22 zeolites with the addition of ZSM-57 zeolite seeds. Notably, the adjustment of SiO2/Al2O3 and Na2O/SiO2 ratios in the starting gel to suitable values is an important factor in preparing the pure Al-rich S-ZSM-35 (Si/Al ratio at about 5) and S-ZSM-22 (Si/Al ratio at about 20) zeolites. The key to success is that the targeted ZSM-35 and ZSM-22 zeolite products have partly the same composite building units as the ZSM-57 zeolite seeds. The obtained Al-rich S-ZSM-35 and S-ZSM-22 zeolites show good crystallinity, typical crystal morphology, large BET surface area, and fully 4-coordinated aluminum species. In addition, as a typical example, the Al-rich S-ZSM-22 zeolite was evaluated by n-dodecane hydroisomerization reaction, which exhibits outstanding performance due to its Al-rich features (Si/Al ratio at about 20) compared with the conventional ZSM-22 zeolite (Si/Al ratio at about 30).
研究领域:
材料科学
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催化化学
✓ 已验证
DOI
高影响因子
FUEL
·
2025
·
IF 7.5
Xiaodan Zhang,Yongjun Zhang,Hongjing Han,Yanan Zhang,Haiying Wang,Jiayu Zhang,Xinyu Liu,Yanguang Chen
Great progress has been made in the catalytic cracking of shale oil by introducing metals into zeolites for regulating acidity to tailor the distribution of olefin products. However, the interaction between the loaded bimetals and their synergistic effect with the acid sites of the zeolite remains controversial. In this work, catalysts of highly stable Fe-La bimetals confined in ZSM-35 zeolite (Fe-La-ZSM-35) were constructed with appropriate acidic properties. Real shale oil and n -heptane as a representative reactant were chosen to explore the catalytic cracking performance of these materials. The Fe-La species formed metal sites bonded to the zeolitic framework in the confined microenvironment of ZSM-35, which established strong interactions. Comparing Fe-La-ZSM-35 with Fe/La-ZSM-35 synthesized by the impregnation method revealed that the direct doping method could better incorporate La and Fe species within the zeolite, resulting in stronger interactions between the bimetals and framework aluminum to form a large number of medium-strong Lewis acid sites (Fe-OH). The ratio of Brønsted acid sites to Lewis acid sites decreased from 1.56 in Fe/La-ZSM-35 to 0.45 in Fe-La-ZSM-35. Furthermore, the electron cloud density at the active Fe-OH site increased due to electron transfer from La to Fe, which promoted the adsorption of carbocations, improved stabilisation of carbocations and bimolecular reactions were inhibited. And the C 3 -C 4 bonds of n -heptane molecules were more easily attacked due to the weak acidity of these acid sites, resulting in propylene being the main product as the reaction C 7 H 16 → C 4 H 10 + C 3 H 6 was dominant during the catalytic cracking of n -heptane. The propylene yield of Fe-La-ZSM-35 increased to 35.35% compared with La-ZSM-35 (22.62%) and Fe/La-ZSM-35 (26.16%) at 600°C. During three reaction-regeneration cycles, n -heptane conversion and propylene selectivity were as high as 89.33% and 30.85%. For real light shale oil, the catalyst achieved a propylene yield and selectivity of 19.24% and 31.0%, demonstrating excellent feedstock generalizability. In addition, Fe-La-ZSM-35 exhibited excellent stability, indicating considerable potential for use in the catalytic cracking of real oil.
研究领域:
化学工程
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催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2018
·
IF 3.649
Guanglu Tang,Mingrui Li,Bin Wang,Yunming Fang,Tianwei Tan
The n -butanol to hydrocarbon (BTH) reaction can produce a series of valuable chemicals and clean fuel precursors. The BTH reaction over different zeolite catalysts (ZSM-5, ZSM-22, Meso-ZSM-22, and ZSM-35) with an emphasis on the production of liquid branched olefins which can be used as precursors for clean gasoline was investigated in this paper. It was found that the structure and acidity of zeolite significantly influences the product distribution in BTH reaction. ZSM-5 zeolite with medium micropore size and large intersections, which are not present in ZSM-22, led to aromatic-rich products and had a long lifetime. ZSM-22 and Meso-ZSM-22 zeolites with unidirectional 10-ring structure achieved a high selectivity to isobutylene and C5+ branched hydrocarbons. Moreover, the Meso-ZSM-22 obtained by desilication with a higher acidity density and improved diffusion property resulted in more liquid organic products than the parent ZSM-22. ZSM-35 exhibited a high product-shape-selectivity for producing isobutylene because of its unique irregular sheet structure and is not suitable for liquid olefin production.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2021
·
IF 5.455
Linjie Guan,Chengming Huang,Dingmei Han,Linhua Zhu,Yi Mei,Dedong He,Yun Zu
Three zeolites ZSM-5, ZSM-35 and ZSM-22 are applied in n -butane cracking to reveal the influence of regional differences in Brønsted acid sites on reaction pathways. The Brønsted acid sites located in the channels of ZSM-5 exhibit a higher catalytic activity and yields to light olefins (especially the ethylene), which can be attributed to more relative contribution of bimolecular pathway. In comparison, more Brønsted acid sites are situated on the external surface or micropore mouths of ZSM-35 and ZSM-22, which are beneficial to propylene production. Note-worthily, almost no propane production on the two zeolites implies the predomination of monomolecular pathway. In situ FTIR technique further discloses that the difference in the reaction pathways is tailored by adsorption configurations of n -butane at two types of Brønsted acid sites. Under comparable conditions, the ZSM-5 performs a relatively good catalytic stability through bimolecular pathway. Furthermore, the correlation between deactivation rate and light olefins reveals that the enhancement of propylene selectivity accelerates the deactivation of ZSM-35 and ZSM-22. While, promotion on the ethylene selectivity is a significant inducement for the deactivation of ZSM-5.
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
危险品化学品经营许可证（带存储）