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沸石分子筛催化合成异丙苯工艺研究 总被引:3,自引:0,他引:3
介绍了沸石分子筛催化合成异丙苯工艺技术在吉化染料厂原苯酚丙酮车间(现为中国石油吉林石化公司双苯厂)异丙苯单元的工业实验情况。结果表明,采用沸石分子筛催化剂生产异丙苯,与固体磷酸催化剂相比,具有收率高、产品质量好、操作费用低、无腐蚀等优点。沸石分子筛催化剂及其工艺用于吉化股份有限公司染料厂原异丙苯单元的技术改造是完全可行的。 相似文献
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以正硅酸乙酯(TEOS)为硅源,十六烷基三甲基溴化铵(CTABr)为模板剂,三氯化铝为铝源在室温条件下合成了介孔硅铝分子筛A1-MCM-41。采用红外光谱(IR)、X射线衍射(XRD)、低温氮吸附等温线等方法对分子筛进行了结构表征。评价结果表明,A1-MCM-41分子筛对桥式四氢双环戊二烯(endo-TCD)具有良好的催化异构化性能。 相似文献
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笔者通过对合成舍钛分子筛的影响因素如模板剂、钛源、硅源、碱源等系统分析,并对舍钛分子筛在选择氧化反应的催化性能方面加以评价,为乙苯氧化脱氢制苯乙烯催化荆设计及研制提出了新思路。 相似文献
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在碱性环境中,采用水热合成法制备得到了不同硅钒比的钒硅中孔分子筛V-MCM-41,利用XRD,IR,TG等表征方法考察了钒的搀杂量与其结构和性能之间的关系,该催化剂对苯乙烯氧化反应具有较好的催化活性,在一定的反应条件下,以H2O2溶液(30%)为氧化剂,以乙腈为溶剂,V-MCM-41(Si/V=25)能使苯乙烯的转化率达到95%以上,产物(苯甲醛+苯甲酸)的选择性不低于90%。 相似文献
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Fe-HMS的合成、表征及催化苯酚羟基化 总被引:1,自引:1,他引:0
以正硅酸乙酯(TEOS)、三氯化铁为原料,十二胺(DDA)为模板剂,采用溶胶-凝胶法合成了铁改性六方介孔硅分子筛(Fe-HMS),利用XRD、FTIR、UV-vis、ESR、TG-DTA、ESEM、TEM及N2吸附-脱附技术对材料结构进行了表征,同时以苯酚羟基化反应为探针考察了Fe-HMS的催化性能。结果表明,Fe-HMS材料由细小的球状纳米粒子组成,材料具有稳定的六方介孔结构,铁已进入六方介孔硅(HMS)载体的骨架;在苯酚羟基化反应中材料显示出较高的催化活性,苯酚的转化率最高可达46.9%,催化剂经450℃焙烧2 h即可再生,重复使用7次苯酚转化率仍可达36.4%。 相似文献
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采用溶胶-凝胶法,以十二胺为模板剂、三氯化铁为铁源,制备了铁改性HMS分子筛(Fe-HMS),利用XRD、TG-DTA、FT-IR、UV-Vis、ESR、ESEM、EDS及N2吸附-脱附测试技术对材料进行了表征.结果表明Fe-HMS材料由圴匀细小的球状纳米粒子组成,分子筛具有良好的介孔结构和热稳定性,铁已进入载体的骨架;分子筛脱模时的热分解及氧化燃烧温度显著降低,红外谱图中802 cm-1及465 cm-1吸收峰强度减弱,而紫外-可见光的吸收性能明显增强,对200~550 nm波段光的吸收达到95%. 相似文献
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钛、银原位改性六方介孔硅HMS材料的表征及性能 总被引:1,自引:1,他引:0
以正硅酸乙酯(TEOS)、钛酸四丁酯及硝酸银为原料,十二胺(DDA)为模板剂,采用溶胶-凝胶法制备了钛、银共改性六方介孔硅分子筛(Ti/Ag-HMS),利用XRD、XPS、uV.Vis、ESEM、EDS、HRTEM、TG-DTA及N2吸附-脱附技术对材料进行了表征.结果表明,Ti/Ag-HMS材料具有"蠕虫状"孔道的六方介孔结构,平均孔径为3.46 mm;钛、银已进入材料的骨架并以Ti4+及Ag0价态存在,金属物种旱纳米级高分散状态;钛、银的引入使材料表现出优越的紫外光吸收性能,同时使材料脱模的热化学分解与氧化燃烧反应进程加快,材料的热稳定性能良好. 相似文献
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Synthesis, Characterization, and Catalytic Properties of Chromium-Containing Hexagonal Mesoporous Aluminophosphate Molecular Sieves 总被引:2,自引:0,他引:2
Chromium-containing hexagonal mesoporous aluminophosphate molecular sieve materials were synthesized, characterized and evaluated for the oxidation of cyclohexane under mild conditions. The catalysts showed remarkable activity for the chosen reaction with very high substrate conversion and excellent product selectivity. In addition, recycling studies over the spent catalysts as well as studies on quenched solutions under the reaction conditions indicated no or very meager loss in activity; thus, the materials behaved truly as heterogeneous catalysts. This observation was well supported by ICP-AES analysis of the filtrates obtained from the washed catalysts where no leaching of active chromium species was detected. Furthermore, the reaction carried out using these filtrates confirmed the absence of active metal ions as it exhibited only a marginal activity. 相似文献
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Preparation of Spherical Hexagonal Mesoporous Silica 总被引:1,自引:0,他引:1
A series of hexagonal mesoporous silica (HMS) have been synthesized by the neutral assemble pathway in water-alcohol cosolvent systems, using dodecylamine (DDA) and tetraethyl orthosilicate (TEOS) as the starting materials. These materials were characterized with powder X-ray diffraction, nitrogen sorption measurement, differential thermal analysis, and transmission electron microscopy. The XRD patterns of these samples exhibited a strong intense reflection at low angle, suggesting the excellent mesostructures of the samples. The particle size of HMS decreased and the morphology of HMS exhibited high textural porosity as the HMS was prepared with high addition rate of TEOS. The particle size of HMS prepared without aging was smaller than that aged for 18 h, due to the reaction time of TEOS was not enough to form complete particles. Addition of NaCl and HCl hindered the formation of HMS mesoporous structure. In contrast, addition of 1-butanol did not affect the formation of HMS mesoporous structure. The sphereical HMS silica with uniform size has been synthesized by adjusting DDA and TEOS concentrations. The shape of HMS became larger and more spherical as the concentrate on of DDA decreased. The stirring rate of the reaction mixture had no effect on either the shape or the size of the spheroid HMS silicas. However, the particles started to crack at higher stirring rates. 相似文献
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通过St(o)ber法制备粒径约100 nm的SiO2纳米粒子,并以非离子表面活性剂嵌段共聚物为模板剂在纳米粒子表面再合成介孔SiO2层.在磷酸盐诱导剂的作用下可使核/壳结构的纳米粒子快速沉淀出来.再通过煅烧除去表面活性剂获得粒径均匀的球形介孔纳米载体.通过动态光散射(DLS)、扫描电镜(SEM)、透射电镜(TEM)、X射线衍射(XRD)、比表面积测定(BET)和氮气吸附脱附测定等技术对材料进行表征.纳米载体的平均有效粒径约为183 nm,介孔孔道为5.5 nm,具有良好的分散性(PDI:0.076),比表面积高达158.6 m2/g,孔容积0.22 cm3/g.结果表明,该法可以简单快速地制备纳米载体. 相似文献