共查询到20条相似文献,搜索用时 109 毫秒
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首先综述了介孔氧化铝的合成方法、合成过程和合成机理,并重点介绍不同铝源合成氧化铝的研究进展。其次,从有序介孔氧化铝在催化剂、吸附剂方面的应用出发,提出了当前有序氧化铝制备研究所存在的问题和发展方向。 相似文献
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《应用化工》2022,(Z2):130-133
为了解介孔材料在卷烟中应用的安全性,论文以介孔氧化铝为研究对象,将其添加到卷烟滤嘴中,按照CORESTA(国际烟草科学研究合作中心)标准方法,通过中性红细胞毒性试验、细菌回复突变试验(Ames试验)以及体外微核试验,对介孔氧化铝的卷烟应用安全性进行了毒理学评价。同时,通过卷烟感官质量评吸评估了介孔氧化铝对卷烟吸味的影响。结果表明,在卷烟滤棒中添加介孔氧化铝后,与对照卷烟相比,不会增加主流烟气总粒相物的遗传毒性,细胞毒性会略有降低,说明介孔氧化铝在卷烟中应用是安全的。卷烟感官质量评价证明介孔氧化铝对卷烟吸味无负面影响,还可以降低烟气刺激性。 相似文献
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The framework and/or textural porosity of mesoporous aluminas (MA), which have great potential for use in applications such
as adsorbents and catalytic supports, is dependent on the conditions used in their preparation. The nanoporosity of MA affects
their adsorption capacity and catalytic activity, and the bulk morphology of an MA is related to the development of the framework
and/or textural porosity. An MA with a well-developed framework pore was found to have a smooth surface, while an MA with
a well-developed textural pore had a coarse and aggregated morphology. 相似文献
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In situ X‐ray diffraction (XRD) investigations of the structural changes of Cs1H3PVMo11O40 Keggin type heteropolyacid catalysts show that during the methacrolein (MA) to methacrylic acid (MAA) oxidation reaction
the crystallites of the HPA disintegrate to small crystallites of about 10 nm in size. When turning the MA supply repeatedly
on and off the observed broadening of the diffraction lines appears and disappears in a rather reversible and reproducible
way indicating that the disintegration of the crystallites must be attributed to the catalytic interaction between MA and
the HPA catalyst. The reported effect shows some similarities to the formation of the so‐called quasiliquid phase by the interaction
of H3PW12O40 with polar organic molecules like pyridine or methanol. Presented results suggest that under the conditions of the catalytic
reaction MA molecules penetrate into the intracrystalline pore system of the HPA and thus the participation of a quasiliquid
phase in the catalytic reaction.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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二甲醚(DME)羰基化制乙酸甲酯(MA),MA加氢合成乙醇工艺是一种新颖、绿色且经济的乙醇合成路线,催化剂成型对实现该工艺工业化具有重要意义。本论文选用拟薄水铝石及硅溶胶为黏结剂,对丝光沸石分子筛(MOR)进行挤条成型,制备了一系列不同黏结剂种类与含量的成型MOR催化剂。通过强度测试以及Weibull函数统计分析,探究了黏结剂对成型MOR的强度以及强度可靠性的影响;X射线衍射、N2物理吸附、NH3程序升温脱附、吡啶吸附原位红外等表征结合活性评价,探究了黏结剂对MOR的物理结构、酸性以及催化性能的作用。结果表明:黏结剂的引入不会影响MOR的晶体结构,且以拟薄水铝石为黏结剂时,催化剂力学性能及DME羰基化催化性能最佳。通过建立MA时空收率、TOF与微孔比表面积之间的定量关系,确定黏结剂不影响MOR内单位活性位点催化能力,产物时空收率与催化剂微孔比表面积呈线性正相关。 相似文献
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Shouying HUANG Xiong XIONG Pei HE Jianhao WANG Ying LI Hongkai LIU Jing LYU Xinbin MA 《化工学报》1951,71(10):4642-4651
The carbonylation of dimethyl ether (DME) to produce methyl acetate (MA) and the hydrogenation of MA to ethanol is a novel, green and economical ethanol synthesis route. The formation of the catalyst is of great significance to the industrialization of this process. In this paper, pseudo-boehmite and silica sol are used as binders, and mordenite molecular sieve (MOR) is extruded to prepare a series of molded MOR catalysts with different binder types and contents. By using strength evaluation and Weibull distribution analysis, we investigated the mechanical stability and reliability of the extruded MOR. Afterwards, XRD, N2-physisorption, NH3-TPD and IR spectra of pyridine adsorption were employed to explore the influence of binder on textural properties, acidity and catalytic performance. The results showed that the crystal structure of MOR was maintained after addition of binder. When the pseudo-boehmite was used as a binder, the catalyst showed the best mechanical property and catalytic activity. By establishing the quantitative relationships among the yield, TOF and structure parameter, it is found that the space time yield of MA was linearly related to the specific surface area of micropores. Meanwhile, the almost constant TOF indicated that the binders did not affect the catalytic capacity of each activesites in MOR for carbonylation of dimethyl ether. 相似文献
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Xiaocheng Chen Juan Guo Zhengwen Fu Heyong He Yingcai Long 《Journal of Porous Materials》2013,20(5):1271-1281
The methylamine (MA) modified FAU zeolites with 5.8 and 80 of silica alumina molar ratio were successfully prepared by the treatment of original FAU zeolites with MA. The obtained materials were investigated with diffuse reflectance infrared Fourier transform spectroscopy, X-ray diffraction, magic-angle spinning nuclear magnetic resonance, thermogravimetry, temperature-programmed desorption of CO2 and NH3 (CO2-TPD and NH3-TPD), nitrogen content analysis, and specific surface area analysis. The formations and thermal stabilities of different Si–N–C groups in the MA modified FAU zeolites were confirmed. The changing of aluminium species due to the interaction of MA and framework/extraframework aluminium (FAL/EFAL) in the modified samples was discovered. The acidity and basicity of the MA modified FAU zeolites were correlated to the hybrid aluminium species and variation of Si–N–C groups, respectively. The catalytic behaviors of the MA modified FAU zeolites were explored by Knoevenagel condensation reaction of benzaldehyde and malonic acid. 相似文献
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合成气经二甲醚(DME)羰基化合成乙酸甲酯(MA),MA进一步加氢制备乙醇是一种新型高效的煤基合成气制备乙醇路线。采用温和的后处理方法改性DME羰基化分子筛,进一步提高DME羰基化效率,对其工业应用具有重要意义。本研究利用四乙基氢氧化铵(TEAOH)对HMOR分子筛改性处理,探讨了有机碱改性处理对HMOR分子筛的结构和DME羰基化催化性能的影响。研究发现,TEAOH浓度为0.3 mol/L时,HMOR分子筛介孔孔容增大约26%,外比表面积增大约10%,DME的转化率增幅达68%。TEAOH水解产生的OH-能够温和脱除HMOR分子筛中的骨架硅,获得介-微多级孔结构,提高DME羰基化反应过程中的传质速率。此外,水解的TEA+在分子筛表面富集,抑制了OH-的过度脱硅,保护分子筛基本骨架结构不被更深层次破坏。 相似文献