CHEMICAL ENGINEERING JOURNAL
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2017
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IF 6.216
Wenwu Zhou,Yasong Zhou,Qiang Wei,Sijia Ding,Shujiao Jiang,Qing Zhang,Meifang Liu
Mesoporous Y composites which exhibit both crystallized micropores and large mesopores with narrow mesopore diameter distributions and controlled pore diameters were successfully synthesized. The composite is synthesized through an elaborate design of the SiO 2 @cationic surfactant cetyltrimethylammonium bromide (SiO 2 @CTAB) micelle swelled by an appropriate amount of 1,3,5-trimenthylbenzene (TMB); it is subsequently fabricated from the condensing of the Y zeolite precursors, which contain Y zeolite seeds, on the mesoscale micelle followed by a hydrothermal crystallization process. The effect of synthesis conditions such as the amounts of CTAB, TMB and TEOS added to the synthesis system on the physicochemical properties of the obtained products was examined. The as-synthesized materials were carefully characterized by employing XRD, N 2 adsorption–desorption, SEM, TEM and pyridine-adsorbed FTIR techniques. The mesoporous Y zeolite exhibited both the typical diffraction characteristics of Y zeolites in the wide-angle XRD pattern, and the typical diffraction characteristics of a narrowly dispersed mesopore structure in the small-angle XRD pattern is successfully synthesized for the first time. Finally, the adsorption capacity for DBT and 4,6-DMDBT by samples with different mesopore diameters were assessed by a batch method. Sample MY-0.5C-0.35T-0.9B showed the highest capacity for adsorbing DBT in model diesel, and sample MY-0.5C-0.35T-1.5B showed the highest capacity for adsorbing 4,6-DMDBT in model diesel. Most importantly, sample MY-0.5C-0.35T-1.5B showed the highest adsorptive rate for both DBT and 4,6-DMDBT, which is at least 10 times faster than that of sample MY-0C-0.35T-0B because of the elimination of the diffusion limitation.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
Frontiers in Chemistry
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2022
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IF 5.545
Huang Meng,Huang Wenbin,Li Anqi,Yang Han,Jia Yijing,Yu Zhiqing,Xu Zhusong,Wang Xiaohan,Zhou Yasong,Wei Qiang
Experiments were carried out to research the different contents of Ga2O3 modification effects on the hydrodesulfurization (HDS) performance of 4,6-dimethyldibenzothiophene (4,6-DMDBT) catalyzed by the stepwise impregnation method. Characterization techniques such as XRD, BET, HRTEM, NH3-TPD, and Py-FTIR were performed to determine the effects of each modification of the catalyst by Ga on the properties of the prepared supports and catalysts. The catalytic effect of gallium is reflected in the fact that the empty d-orbitals of Ga elements participate in the formation of molecular orbitals in the active center and change their orbital properties, thus generating a direct desulfurization active phase suitable for complex sulfides for endpoint adsorption. The characterization results indicated that the introduction of Ga2O3 with appropriate content (2 wt.%) promoted Ni and Mo species to disperse uniformly and doping of more Ni atoms into the MoS2 crystals, which also increased the average stacking number and the length of MoS2. As a result, more NiMoS active phases were favored to form in the system. The specific surface area and the amounts of acid sites were increased, facilitating the adsorption of reactant molecules and the HDS reactions. The HDS results also suggested the effects of Ga modification play a very important role in the catalytic performance of the corresponding catalysts. The catalyst Ga–Ni–Mo/Al2O3 exhibited the highest conversion rate towards 4,6-DMDBT HDS when the amount of Ga2O3 loading was 2 wt.% with an LHSV of 2.5 h−1 at 290°C and Ga modification also can effectively improve the direct desulfurization (DDS) route selectivity in varying degrees.
研究领域:
催化化学
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材料科学
✓ 已验证
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2019
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IF 14.229
Wenwu Zhou,Li Yang,Lang Liu,Zhiping Chen,Anning Zhou,Yating Zhang,Xinfu He,Faxiang Shi,Zegao Zhao
Highly ordered mesoporous TiO 2 -Al 2 O 3 composites with different TiO 2 mass contents (MA-xTi) were successfully synthesized via an improved solvent evaporation-induced self-assembly method and the corresponding NiMo supported hydrodesulfurization (HDS) catalysts were prepared via wetness incipient co-impregnation method. The materials were characterized by means of XRD, ICP-OES, N 2 physical adsorption-desorption, SEM, TEM, Py-FTIR, H 2 -TPR, HRTEM and XPS and the catalytic activities for 4,6-dimethyldibenzothiophene (4,6-DMDBT) HDS over the prepared NiMo/MA-xTi series catalysts were investigated. The results show that the crystal forms, crystal morphologies, pore structures, pore arrangements and acidity properties of the MA-xTi samples varied with the incorporation and increase of TiO 2 species; the interaction between the active metals and the support materials (MSI) can be modulated by the incorporation of TiO 2 species, and TiO 2 incorporation also can promote the formation of the so-called “Type II” NiMoS active phase via changing the morphology of Ni promoted MoS 2 slabs, promoting the sulfidation of both Ni and Mo species and enhancing the proportion of NiMoS phase. The catalytic evaluation results show that the enhancement in the overall HDS activity of the NiMo/MA-xTi series catalysts were mainly contributed by the enhancement in the hydrogenation desulfurization (HYDS) activity. Catalyst NiMo/MA-20Ti exhibited the superior catalytic performance due to its highly ordered mesopore arrangement, proper acidity, moderate MSI, moderate stacking and high proportion of NiMoS phase which leads to more highly active “Type II” active sites.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子