Catalysis Science & Technology
·
2019
·Vol. 9
·期 11
·2812-2827
·
IF 5.726
Suyao Liu,Yurong He,Huaike Zhang,Zhiqiang Chen,Enjing Lv,Jie Ren,Yifeng Yun,Xiaodong Wen,Yong-Wang Li
Ga-Doped ZSM-22 zeolites were synthesized successfully via a hydrothermal method by directly incorporating Ga species into the zeolite framework. It appeared that the as-prepared Ga-substituted zeolites possessed high crystallinity, uniform morphology and open pore structure. The XRD, FTIR, XPS as well as 71Ga and 29Si MAS NMR results confirmed the presence of Ga species in the framework of zeolites and the formation of the Ga–OH–Si group, thus leading to a significant decrease of Brønsted acidity because of the lower acidity of the Ga–OH–Si bridge hydroxyl compared to that of the Si–OH–Al group. These characteristics ensured that the Pt-loading [Al, Ga]-ZSM-22 catalyst exhibited lower cracking activity and higher selectivity (about 78.2% at 90.5% of conversion) in the n-dodecane isomerization than the parent Pt/ZSM-22 catalyst, due to the more balanced bifunctionality between acid sites and metal sites. DFT calculations revealed that Al and Ga incorporation was mostly prevalent at the T2, T3 and T4 sites, while Fe heteroatom substitution occurred equivalently in four sites. Bader charge analysis suggested that the acidity decreased in the order of Al-ZSM-22 > Ga-ZSM-22 > Fe-ZSM-22, and the cracking activity exhibited the order of Al-ZSM-22 ≫ Ga-ZSM-22 > Fe-ZSM-22. Therefore, it could be concluded that the isomerization was facilitated by the combination of the heteroatom location and the acidity strength. Remarkably, no significant decline of crystallinity and special surface area of Ga-doped zeolites was observed after the high temperature calcination, revealing higher stability of Ga than Fe in the zeolite framework.
研究领域:
催化化学
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材料科学
·
理论化学
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产品关联
DOI
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 51
·28909-28917
·
IF 2.936
Haoran Li,Chenglian Liu,Yan Wang,Jiajun Zheng,Binbin Fan,Ruifeng Li
ZSM-48 and ZSM-22 zeolites with similar Si/Al molar ratio have been treated with alkali to modify the pore structures and acidity, and alkali treated ZSM-22 and ZSM-48 samples have been characterized by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), N2 adsorption/desorption, Nuclear Magnetic Resonance (NMR), NH3-Temperature Programmed Desorption (NH3-TPD) and Pyridine-Fourier Transform Infrared Spectroscopy (Py-FTIR). Characterization results indicate that NaOH treatment could improve the mesoporous structure for both ZSM-22 and ZSM-48. NaOH treatment modifies the acidity of ZSM-22 and ZSM-48 diversely. The n-hexane hydroisomerization performances of Pt supported protonic form ZSM-22 and ZSM-48 (Pt/HZSM-22 and Pt/HZSM-48) bifunctional catalysts have been evaluated in a fixed bed reactor. Catalytic results indicate that catalytic activity and selectivity depend on both pore structure and acidity of zeolites. In comparison of Pt/HZSM-22 and Pt/HZSM-48, Pt/HZSM-22 shows better n-hexane hydroisomerization performance at relatively low temperature (<300 °C), meanwhile, at relatively high temperature (>300 °C) Pt/HZSM-48 exhibits better catalytic performance. Moreover, alkali treated Pt/HZSM-48 could produce more di-branched isomer compared with alkali treated Pt/HZSM-22.
研究领域:
催化
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化学工程
·
材料科学
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产品关联
DOI
PubMed
高影响因子
FUEL
·
2024
·
IF 6.7
Jinhui Song,Tianfu Zhang,Mengjiao Xing,Junfeng Zhou,Lu Tang,Jiaxin Xie,Zimin Peng,Wenyao Gu,Jianyu Tang,Suyao Liu,Tong Chang,Yi Liu,Yiwen Fang
With the potential application of biomass-derived feedstock upgradation to sustainable aviation fuels, it is essential to enhance the hydroisomerization performance of ZSM-22 zeolite while improving its resistance to residual oxygen-containing compounds. As the defect sites in the ZSM-22 zeolite, the abundant Si-OH groups are closely related to the catalytic performance and stability, serving as the main attack sites for the generated water. In this work, liquid-mediated defect-healing treatment is performed to heal Si-OH to Si-O-Si, leading to the enhancement of the crystallinity and pore connectivity without affecting the Si/Al, micropore volume, and morphology and preventing the micropores blockage and dealumination caused by conventional silylation and silication procedures. The outcome of the declined Si-OH groups is the reduction of the Lewis acid site without altering the Brønsted acidity. In the n-dodecane hydroisomerization, the catalyst obtained by the liquid-mediated defect-healing treatment route shows an increased conversion and isomer yield compared to the parent and healed catalysts prepared by other healing methods. This is mainly due to enhanced confinement of the micropore void, resulting in decreased apparent activation energy and reduced yield to multi-branched isomers prone to cracking. Furthermore, the healed catalyst exhibits improved resistance and structure stability in the hydroisomerization of feedstocks containing butanol. The work provides a prospective application of ZSM-22 zeolite in the hydroisomerization for complex and severe reactants through the essential Si-OH healing method.
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
Catalysis Science & Technology
·
2018
·Vol. 8
·期 24
·6407-6419
·
IF 5.365
Pengyu Niu,Hongjuan Xi,Jun Ren,Minggui Lin,Qiang Wang,Xiaoyan Chen,Pengfei Wang,Litao Jia,Bo Hou,Debao Li
A core–shell ZSM-22 (Z@S) was synthesized via epitaxial growth. The characterization results of Z@S validated that the acid sites located on the external surface of core ZSM-22 were passivated by the epitaxial shell of highly siliceous ZSM-22 and the acid strength of ZSM-22 remained unchanged. For comparison, highly siliceous and boron-containing ZSM-22 were also synthesized and characterized. In n-dodecane hydroisomerization, highly siliceous ZSM-22 almost without acid sites at the external surface achieved a much higher iso-dodecane selectivity than boron-containing ZSM-22 with weak acid sites. Z@S with strong acid sites and passivated surface acidity showed high activity and favored pore mouth catalysis but exhibited a lowered iso-dodecane selectivity. The reduced external surface acid sites enhanced the diffusion of n-alkane into the micropores, leading to severe cracking reaction caused by acid sites on the internal surface. Further modifying Z@S via micropore blockage could greatly inhibit cracking reaction inside the micropores and confine isomerization at the pore mouth of ZSM-22. This new ZSM-22 catalyst achieved higher activity and a higher iso-dodecane yield than catalysts with weak acidity.
研究领域:
催化化学
·
材料科学
·
石油化工
·
纳米结构材料
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表面化学
✓ 已验证
DOI
高影响因子
MOLECULES
·
2025
·Vol. 30
·期 16
·3319
·
IF 4.6
Tong Chang,Renhui Deng,Jiaxin Xie,Jianyu Tang,Wenyao Gu,Zimin Peng,Suyao Liu
The abundant Si-OH groups serving as the defect sites in the ZSM-22 zeolite framework are not only closely associated with physicochemical properties and catalytic performance but are also the primary sites for attack by water molecules, thereby restricting applications involving or producing water. In the present study, a liquid-mediated healing process was used to convert the Si-OH groups in ZSM-22 zeolite into Si-O-Si bonds. The systematic investigation of the treatment solution’s composition and the hydrothermal conditions revealed that the crystallinity of ZSM-22 zeolite can be effectively enhanced following optimal healing treatment. Furthermore, the healed ZSM-22 zeolite exhibited enhanced ordering degree and pore connectivity without significant changes to the Si/Al and morphology. Moreover, the decline in Si-OH groups reduced the Lewis acid sites without altering the Brønsted acidity, which led to a slight decrease in the dispersion of Pt particles. In n-decane hydroisomerization, compared to the parent ZSM-22 zeolite catalyst, the healed catalyst demonstrates higher reactant conversion and increased isomer yield, attributing to its enhanced confinement within the micropore voids, which leads to a reduced yield of multi-branched isomers susceptible to cracking. This study presents a potential application of ZSM-22 zeolite in hydroisomerization for complex and challenging feedstocks.
研究领域:
催化化学
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材料科学
·
化学工程
·
石油化工
·
沸石化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOMASS & BIOENERGY
·
2022
·
IF 5.774
Wenlu Zhang,Chunrong Wang,Beining Luo,Peihang He,Lei Zhang,Guoqiang Wu
With the aim of developing efficient heterogeneous catalysts for production of clean biodiesel through the transesterification process, a novel Mo catalyst supported on the outer surface of ZSM-22 ( x Mo/ZSM-22) was developed and synthesized successfully with the wet impregnation method. The characterization results showed that the Mo(VI) oxide species were highly dispersed on the surface of catalysts under the Mo-loading not higher than 5%, and the aggregation of the MoO 3 nanoparticles were detected above the Mo-loading of 5%. Meanwhile, the maximum acid intensity was also exhibited in the 5Mo/ZSM-22 catalyst. As a result, the catalytic performance of Mo/ZSM-22 catalysts in the transesterification of waste cooking soybean oil (WCSO) was significantly improved compared with the untreated ZSM-22 catalyst. Especially, the 5Mo/ZSM-22 showed the good activity (X WCSO of 59.29%, S Biodiesel of 99.86%), which was mainly due to the well dispersed Mo species and the larger acidity. Additionally, the 5Mo/ZSM-22 catalyst exhibits good stability and the high biodiesel selectivity , and the fuel properties of the as-synthesized biodiesel meet ASTM D6751 standards. This work provides a useful synthesis strategy of transesterification catalysts for the preparation of biodiesel.
研究领域:
化学工程
·
催化
·
可再生能源
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环境科学
✓ 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
CRYSTAL GROWTH & DESIGN
·
2018
·
IF 3.972
Pengyu Niu,Ping Liu,Hongjuan Xi,Minggui Lin,Jungang Wang,Xiaoyan Chen,Litao Jia,Pengfei Wang,Bo Hou,Debao Li
The crystallization mechanism of pure-silica ZSM-22 was investigated in the presence of seeds. Seed crystals played a significant role in the nucleation and crystal growth. Experimental findings revealed that the seed crystals acted as a substrate for crystal crystallization, and nucleation only occurred via the interaction between the organic structure-directing agent (OSDA), 1,6-hexanediamine, and seed crystal surface. Oligomeric silicate species in the liquid phase as nutrients directly crystallized on the crystals. The crystal growth occurred via layer-by-layer construction on the external surface of the seed crystals. The major chemical process occurring in the crystallization process was (i) dissolution of the large seed crystals into many thin needle-like crystals, (ii) dissolution of silica particles to form oligomeric silicate species, (iii) interaction between template molecules and the crystal framework which promoted nucleation, and (iv) formation of fully crystalline pure-silica ZSM-22 via layer growth. The morphology of pure-silica ZSM-22 can be controlled by the interaction between OSDA and the crystal framework which affected crystal growth in the a- and b-orientation.
研究领域:
材料科学
·
无机化学
·
沸石合成
·
晶体生长
✓ 已验证
DOI
高影响因子
Science China-Technological Sciences
·
2024
·Vol. 67
·期 8
·2413-2426
·
IF 4.4
Cheng LeiLei,Chen RuiZhe,Zhu WeiQiang,Tian ShaoNan,Gu Jing,Yuan HaoRan,Chen Yong
The hydrogenolysis/hydrocracking of waste polyethylene (PE) has recently been intensively studied, with the general pursuit of low-temperature reaction conditions, increased oil-phase yield, and narrower carbon chain distribution. Before this, we utilized a ball-milled ZSM-22 catalyst loaded with Ru nanoparticles (NPs), which exhibited excellent hydroconversion performance. It deconstructed PE into >80 wt.% oil products under low temperatures and short reaction times. Herein, we investigated the influence of varying temperature/pressure parameters on the degree of specific hydrocracking/internal hydrogenolysis/terminal hydrogenolysis reactions. From the comprehensive energy efficiency perspective, including stirring, reaction, and product separation, as well as taking into account the degree of product isomerization and catalyst lifespan, we analyzed the optimization of parameters. This research abandons the notion that lower temperatures are better and proposes a more comprehensive evaluation framework for low-consumption hydroconversion of PE to produce high-value products.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2023
·
IF 22.1
Cederick Cyril Amoo,Joshua Iseoluwa Orege,Qingjie Ge,Jian Sun
Fuel production is an option for valorizing CO 2 , yet deficient catalysts meeting the standard fuel production has impeded progress of this promising technology. Herein, liquid fuel synthesis is rationalized over a catalyst consisting ‘C′, ‘Na’, and ‘Fe’, as in NaFe@C, configured with ZSM-22 and ZSM-5 in CO 2 hydrogenation. While the ‘Na’ and ‘C′ functioned as structural promoters on Fe to enhance CO 2 conversion and olefins synthesis, the characteristics of the zeolites facilitated oligomerization of lighter hydrocarbons. A high C 5 + selectivity was obtained over the HZSM-22 composite in CO 2 hydrogenation dominated by olefins and isoparaffins. Model reactions for exemplar oligomerization activity over the zeolites revealed ZSM-5 as highly active with selectivity towards isoparaffins and aromatic. The ‘Na’ cations induce Lewis’s acid sites (LAS) which suppresses hydrocracking during chain growth. This consistency, revealed between the model and CO 2 hydrogenation unlocks a door to zeolite usage in CO 2 hydrogenation to clean heavy hydrocarbons.
研究领域:
催化化学
·
能源科学
·
材料科学
✓ 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
CATALYSIS LETTERS
·
2025
·Vol. 155
·期 12
·1-12
·
IF 2.4
Ge Pengyu,Liu Xiyu,Li Xincheng,Fan Mingming,Zhang Pingbo
In this study, highly crystalline ZSM-22 zeolite with a TON topology was synthesized via a seed–template co-assisted hydrothermal method and subsequently modified with low-concentration NH₄Cl to introduce Brønsted acid sites. The characterization of the catalyst revealed its well-defined rod-like crystals (2–5 μm), one-dimensional straight channels (0.46 × 0.57 nm), microporous surface area of 210 m 2 ·g −1 , Brønsted-to-Lewis (B/L) acid ratio of 0.45, and excellent thermal stability. Under optimized reaction conditions (270 °C, 3 h, 6 wt% catalyst), the catalyst achieved a 95.01% conversion of oleic acid and a 77.72% yield of isostearic acid. The confinement effect of the 1D channels effectively suppressed undesired side reactions, offering significantly enhanced selectivity compared to commercial zeolites such as ZSM-5. Thermogravimetric analysis demonstrated that calcination at 550 °C successfully removed coke deposits and restored catalyst activity. After five regeneration cycles, the conversion and yield remained at 89.50% and 72.80%, respectively, with less than 6% loss. These findings provide theoretical and technical guidance for the high-value catalytic transformation of biomass-derived fatty acids. Graphical H-ZSM-22 catalyst with good reusability
研究领域:
催化化学
·
材料科学
·
绿色化学
·
生物质转化
·
石油化工工程
✓ 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）