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介孔材料Al-SBA-15的合成研究进展 总被引:1,自引:0,他引:1
Al掺杂的介孔SBA-15材料不仅保持了介孔SBA-15材料原有的结构特征,还赋予了材料新的催化活性位,成为近年来介孔材料领域最为活跃的研究对象之一。本文详细阐述了近十几年来Al-SBA-15介孔材料的研究进展,比较了各合成方法之间的区别,并讨论了Si/Al摩尔比、合成方法和反应条件等因素对Al原子嵌入SBA-15介孔骨架的效率以及介孔材料的有序性、稳定性和酸性的影响。同时总结出加深对合成机理的研究,优化合成过程,使用较简单且高效的方法制备具有完全晶化骨架和较高Al含量的介孔Al-SBA-15是未来介孔Al-SBA-15合成研究的新方向。 相似文献
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以SBA-15介孔分子筛为载体,采用浸渍法制备了Nb-SBA-15介孔分子筛,采用X射线衍射、BET、Fourier变换红外光谱、热重–差热分析和吡啶吸附红外光谱分析等测试手段对其进行分析,用喹啉的十二烷溶液为模型化合物,采用静态吸附法在间歇式反应器中对其吸附脱氮性能进行评价。结果表明:Nb-SBA-15分子筛具有高度有序的二维六方介孔结构,并且具有一定的酸性,焙烧温度为300℃,铌酸负载量(质量比)为10%时,Nb-SBA-15具有最高的吸附脱氮率,为65.19%。 相似文献
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采用水热直接合成法合成了n(Si)∶n(Al)为10、25和50的Al-SBA-15介孔分子筛。用X射线衍射对材料进行了表征,结果表明,Al-SBA-15保持了母体SBA-15高度有序的六方介孔结构。并研究其在苯酚与甲基叔丁基醚的烷基化反应中的催化性能,结果表明,Al-SBA-15(25)催化剂具有较高的苯酚转化率和2,4-二叔丁基苯酚选择性,最佳工艺条件为:反应温度160 ℃,n(甲基叔丁基醚)∶n(苯酚)=1.5∶1,空速1.5 h-1。在此条件下,苯酚转化率为73.2%,2,4-二叔丁基苯酚选择性为57.9%,催化剂Al-SBA-15(25)可稳定运行约80 h。 相似文献
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Y分子筛/介孔Al-SBA-15复合材料与脱铝Y分子筛的表征和重油加氢裂化性能 总被引:1,自引:1,他引:0
采用两步法和水热-化学方法制备了具有高水热稳定性的Y分子筛/介孔Al-SBA-15复合材料和含有介孔的脱铝Y分子筛,用浸渍法制备了加氢裂化催化剂,并利用XRD、N2 吸附、SEM、XRF和TEM等分析手段对Y分子筛/介孔Al-SBA-15复合材料、含有介孔的脱铝Y分子筛及其催化剂的物化性质进行了对比分析。相同条件下催化剂的重油加氢裂化性能对比评价结果表明,以Y分子筛/介孔Al-SBA-15复合材料为载体的加氢裂化催化剂的中间馏分油收率和中油选择性高达66.21%和84.5%,比以脱铝Y分子筛为载体的催化剂分别提高了5.68%和5.7%。 相似文献
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介孔分子筛SBA-15通过化学改性,可将一些官能团引入到其骨架中改善催化性能,其中以铝改性效果最好,铝改性后的SBA-15介孔分子筛的水热稳定性及酸性明显提高。介绍了A1-SBA-15介孔分子筛的合成及应用现状,展望了介孔分子筛A1-SBA-15未来的发展方向。 相似文献
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对分子筛的发展历程、SBA-15介孔分子筛的合成方法、近年来以SBA-15介孔分子筛作主体合成主-客体复合材料的研究情况、SBA-15分子筛及其复合材料的应用进行了综述,并对SBA-15介孔分子筛在未来的发展进行了展望. 相似文献
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Al-SBA-15 was prepared by one-step hydrothermal synthesis method, and was characterized by X-ray diffraction, N2-adsorption, transmission electron microscope and Fourier infrared spectra of chemisorbed pyridine (Py-IR). The results showed that Al-SBA-15 had well-ordered hexagonal mesopores. As compared with Si-SBA-15, Al-SBA-15 had thicker pore wall, higher surface area, and stronger Lewis acidity. Due to the stronger Lewis acidity, Mn/Al-SBA-15 catalyst prepared by impregnation showed better activity than Mn/Si-SBA-15 in the selective catalytic reduction of NO by NH3. 相似文献
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Hyung Won Lee Suek Joo Choi Sung Hoon Park Jong-Ki Jeon Sang-Chul Jung Sang Chai Kim Young-Kwon Park 《Nanoscale research letters》2014,9(1):376
The catalytic co-pyrolysis of a seaweed biomass, Laminaria japonica, and a typical polymer material, polypropylene, was studied for the first time. A mesoporous material Al-SBA-15 was used as a catalyst. Pyrolysis experiments were conducted using a fixed-bed reactor and pyrolysis gas chromatography/mass spectrometry (Py-GC/MS). BET surface area, N2 adsorption-desorption isotherms, and NH3 temperature programmed desorption were measured to examine the catalyst characteristics. When only L. japonica was pyrolyzed, catalytic reforming slightly increased the gas yield and decreased the oil yield. The H2O content in bio-oil was increased by catalytic reforming from 42.03 to 50.32 wt% due to the dehydration reaction occurring on the acid sites inside the large pores of Al-SBA-15. Acids, oxygenates, mono-aromatics, poly aromatic hydrocarbons, and phenolics were the main components of the bio-oil obtained from the pyrolysis of L. japonica. Upon catalytic reforming over Al-SBA-15, the main oxygenate species 1,4-anhydro-d-galactitol and 1,5-anhydro-d-manitol were completely removed. When L. japonica was co-pyrolyzed with polypropylene, the H2O content in bio-oil was decreased dramatically (8.93 wt% in the case of catalytic co-pyrolysis), contributing to the improvement of the oil quality. A huge increase in the content of gasoline-range and diesel-range hydrocarbons in bio-oil was the most remarkable change that resulted from the co-pyrolysis with polypropylene, suggesting its potential as a transport fuel. The content of mono-aromatics with high economic value was also increased significantly by catalytic co-pyrolysis. 相似文献
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异丙醇铝作为铝源通过直接法制备Al-SBA-15介孔分子筛,经1 mol/L硫酸浸渍,得到固体超强酸SO42-/Al-SBA-15,利用X-射线粉末衍射、透射电镜和N2吸附-脱附实验对其进行表征.合成偏苯三酸三辛酯中SO42-/Al-SBA-15的催化活性高于SBA-15、Al-SBA-15,在210℃,偏苯三酸酐和2-乙基己醇的摩尔比为1∶4,催化剂用量为总反应原料质量的4%,反应6h,偏苯三酸三辛酯的酯化率为96.7%.催化剂重复使用六次,酯化率仍为94.4%. 相似文献
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制备了一系列Si/Al比(均为摩尔比,下同)从15到50的Al-SBA-15固体酸催化剂,并将其应用于硬脂酸与三乙醇胺的酯化反应中。结果表明,Si/Al比为25的Al-SBA-15固体酸催化剂的催化活性和选择性较高,反应6 h酯胺的酸值可降至1.78 mg KOH/g,单双酯总质量分数可达84.79%;该催化剂重复使用6次,催化活性没有明显降低,说明该催化剂具有高的稳定性。采用XRD、N2吸附脱附、透射电镜和吸附吡啶的红外光谱对催化剂的结构、比表面积和表面酸性进行了表征,结果表明,Si/Al比为25的Al-SBA-15催化剂保持了SBA-15的结构,具有大的比表面积和均一的孔径,在催化剂表面同时存在Lewis酸和Brnsted酸。 相似文献
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在强酸性和水热条件下以硅酸钠(Na2SiO3·9H2O)为硅源合成表面含磺酸基的介孔分子筛催化剂SBA-15-SO3H。XRD结果表明,该分子筛具有规则的六方立柱形介孔结构。SBA-15-SO3H用于叔丁醇和乙醇合成乙基叔丁基醚(ETBE)的醚化反应研究,分别考察了反应温度、原料配比和反应时间等因素对醚化反应的影响。最佳操作条件为:温度120 ℃,n(乙醇)∶n(叔丁醇)=2∶1,反应时间5 h,m(催化剂) ∶m(原料)=1∶10。在此条件下,叔丁醇的转化率为62.83%。 相似文献