MOLECULES
·
2021
·Vol. 26
·期 5
·1462
·
IF 4.412
Hao Xu,Jie Zhu,Xiong Wang,Chao Shen,Shengshen Meng,Kai Zheng,Chao Lei,Longfeng Zhu
Developing sustainable routes for the synthesis of zeolites is still a vital and challenging task in zeolite scientific community. One of the typical examples is sustainable synthesis of aluminosilicate EU-1 zeolite, which is not very efficient and environmental-unfriendly under hydrothermal condition due to the use of a large amount of water as solvent. Herein, we report a sustainable synthesis route for aluminosilicate EU-1 zeolite without the use of solvent for the first time. The physicochemical properties of the obtained EU-1 zeolite are characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry-differential thermal analysis (TG-DTA), N2sorption, inductively coupled plasma (ICP) analysis, and solid nuclear magnetic resonance (NMR), which show the product has high crystallinity, uniform morphology, large BET surface area, and four-coordinated aluminum species. Moreover, the impact of synthesis conditions is investigated in detail. The sustainable synthesis of aluminosilicate EU-1 zeolite under solvent-freeKeywords:zeolite;aluminosilicate EU-1;sustainable route;solvent-free
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2023
·
IF 4.7
Youbing Zhu,Xiangfei Ding,Jian Chen,Hongyan Wang,Hui Wang
One-dimensional microporous zeolite, EU-1, has tighter restriction for bulky intermediates, exhibiting more favorable selectivity of propylene than ZSM-5 in catalytic cracking. However, the diffusion limitation accelerates coke generation, passivates acid sites and deactivates the zeolite. In this study, a strategy was proposed to etch amorphous species between EU-1 nanocrystals using NH 4 F solution to improve the diffusion property. It was found that the etching process occurred on the crystal surface and mesopores were introduced. Catalytic performance evaluation in n-hexane cracking demonstrated that the maximum propylene selectivity over parent EU-1 was 33.6 wt% ( vs . 5.7 wt% for ZSM-5). The n-hexane conversion was increased by 24 wt% over EU-1 etched in 20 wt% NH 4 F solution. Moreover, the introduction of mesopores provides accommodation space for coke. This study developed hierarchical EU-1 zeolite with favorable diffusion ability and reported a feasible strategy to improve the catalytic performance of EU-1 for propylene production.
研究领域:
化学工程
·
催化科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2024
·
IF 4.1
Youbing Zhu,Ketao Shi,Tao Zhang,Nianming Jiao,Hui Wang
One-dimensional microporous zeolite, EU-1, exhibits more favorable selectivity of propylene in cracking of petroleum components. However, it faced the problem of low catalytic activity for the poor utilization of active sites. In this work, dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (TPOAC) was used to functionalize protozeolitic units and inhibit the excessive growth of crystals by the long hydrophobic alkyl chain. The introduction of TPOAC decreased the crystal sizes into nanoscale, enhanced the mesoporous volume of EU-1 zeolite, and exposed more external acid sites. Moreover, TPOAC could interact with Al species, and in this case, fewer Al atoms were incorporated into the zeolite framework, reducing the acid strength and amount. Intelligent gravitation analyzer test indicated that the zeolite prepared with the presence of 0.30 g TPOAC exhibited the largest accessible volumes in n-hexane adsorption, and the highest accessibility of acid sites, which synergistically promoted cracking of n-hexane for the production of light olefins.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2023
·Vol. 13
·期 10
·3060-3068
·
IF 5
Guanghua Liang,Jianyi Chen,Tao Dou,Zhijie Wu,Xiaofeng Li,Yuanshuai Liu
EU-1 zeolite is employed as an active component of a catalyst for isomerization or hydroisomerization of C8 aromatics (i.e., xylenes, ethylbenzene) in petrochemical processes to increase the para-xylene yield. However, conventional manufacturing of EU-1-based catalysts involves the production of mother liquors for zeolite synthesis which usually contain plentiful unreacted raw materials, or the negative impact of incorporated binders in mass transfer during reactions over shaped catalysts. Herein, we developed a novel route to prepare the monolithic EU-1 zeolite, and used it as an active component of a catalyst for hydroisomerization of ethylbenzene with meta-xylene. Recrystallization of the shaped zeolite precursors composed of incompletely crystallized zeolites with amorphous silica and alumina powders as binders in recycled mother liquor led to formation of the monolithic EU-1 zeolite. Transformation of binder species to a full-zeolitic phase was corroborated comprehensively by characterization methods. Compared with the conventionally fabricated counterpart, the monolithic EU-1 zeolite possessed similar mechanical strength, high crystallinity, and high acidity and, in particular, enhanced mesoporosity, which led to improved catalytic performances in hydroisomerization reactions. Our developed synthetic strategy provides an effective way to produce the monolithic EU-1 zeolite, but is also a reference for the sustainable production of other types of zeolitic materials for energy-related applications.
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
MAIN GROUP CHEMISTRY
·
2020
·Vol. 19
·期 2
·117-124
·
IF 0.845
Zhao Xue-Yan,Shi Yan-Shu,Pang Mao-Lin,Zhang Wei-Na,Li Yun-Hui
The controllable synthesis of MOF materials is of great significance for its application. At present, the regulation of MOF morphology is mainly limited to those composed of transition metal elements, such as IRMOF, ZIF-8, HKUST-1, UiO-66, and MIL-MOFs etc, and few reports about the fabrication of micro/nano sized lanthanide MOFs could be found in literature. In this paper, micron sized Eu-1,4-NDC-fcu-MOF octahedral particles were obtained via a modified solvothermal method by using methylamine as a modulator. The luminous efficiency of Eu3+ was greatly improved due to the efficient energy transfer from the 1,4-NDC ligand to rare earth ion. The resultant Eu-1,4-NDC-fcu-MOFs particles could be used to detect benzidine in ethanol solution effectively, and as the concentration of benzidine increased, the fluorescence intensity of Eu-1,4-NDC-fcu-MOFs gradually decreased. Due to the good stability, high luminescent intensity and excellent sensitivity, this work further demonstrates that Ln-MOF are ideal fluorescent probes to identify specific molecules.
研究领域:
材料科学
·
化学工程
·
分析化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）