文献类型：期刊文献

中文题名：Pt和Al_2O_3改性SO_4^(2-)/ZrO_2正己烷异构化反应性能

英文题名：n-Hexane Isomerization over Pt and Al_2O_3-Promoted SO_4^(2-)/ZrO_2

作者：周晓龙[1];余国贤[1];金亚清[1];唐超[1];李承烈[1]

机构：[1]华东理工大学石油加工研究所,上海200237

年份：2007

卷号：33

期号：3

起止页码：309

中文期刊名：华东理工大学学报（自然科学版）

外文期刊名：Journal of East China University of Science and Technology

收录：CSTPCD;;EI(收录号：20072910703767);Scopus;北大核心:【北大核心2004】；CSCD:【CSCD2011_2012】；

基金：国际重点合作项目计划(2004CB720603)

语种：中文

中文关键词：正己烷;异构化;Pt和氧化铝改性SO42-/ZrO2

外文关键词：n-hexane; isomerization; Pt and Al-promoted SO4^2-/ZrO2

摘要：在保持其他制备条件,如pH、干燥条件、焙烧温度、Pt的浸渍条件以及Al2O3和Pt的含量相同的情况下,通过Al的不同引入方法,即共沉淀法(CP)、成型法(SH)、悬浮法(SU)和混和法(MI),制备了4种Pt-SO42-/ZrO2-Al2O3(PSZA)催化剂。使用N2吸附和微库仑仪分析了催化剂的组织结构和硫含量。分别使用X射线光散射仪(XRD)、H2程序升温还原(TPR)及NH3程序升温解析(TPD)研究了催化剂的晶相结构、氧化还原性质和表面酸性质。在固定床反应器上考察了反应温度对催化剂正己烷异构化反应的影响和异构化产物分布。成型法催化剂仅探测到四方晶相,表明该种Al的引入方法延缓了四方相转为单斜相;并且成型法催化剂具有一个强的最低的TPR还原峰温度,表明Al的成型引入法增强了硫的还原。催化考评结果表明成型法催化剂具有最高的催化性能。催化剂的物化表征结果表明了催化活性同催化剂的氧化还原性质关联较好,而同硫含量、酸强度及强酸位数量关联性不好。实验结果表明Al的引入方式对于PSZA催化剂在正己烷异构化中具有高催化活性非常关键。
Four Pt-SO4^2-/ZrO2-Al2O3 （PSZA）samples were prepared by different introduction methods of Al, that is, co-precipitation introduction method （CP）, shaping introduction method （SH）, suspension introduction method （SU） and mixing introduction method （MI）, with the same other preparation conditions, such as, precipitation pH, dry conditions, calcination temperatures, Pt impregnation conditions, and Al2O3 and Pt contents. Tissue structure of the samples and their sulfur content were measured by N2 adsorption and a microcoulometer, respectively. Crystalline structures, redox properties and surface acid properties of the catalysts in different Al introduction methods were studied by X-ray diffraction （XRD）, H2-temperature-programmed reduction （TPR） and temperature-programmed desorption （TPD） of NH3, respectively. Effect of reaction temperature on n-C6 isomerization over the catalysts and the isomerization product distribution for the catalysts were investigated in a flow-type fixed-bed reactor. For the SH15 sample, only the tetragonal phase was detected, which showed that the Al introduction method of SH15 retarded the transformation from the tetragonal phase to the monoclinic phase. Compared with the other catalysts, SH15 has a strong peak at lowest temperature, showing an enhancement of sulfate reduction by the shaping introduction method. For the catalysts from four Al introduction methods, SH15 has the best catalytic performance due to its highest conversion and selectivity. The physico-chemical characterizations of the samples revealed that the catalytic activity is directly correlated with redox property rather than sulfur content, acid strength and the total number of strong acid sites. The results show that Al introduction method is a crucial step for catalytic activity of Pt and Al-promoted SZ catalyst in n-hexane isomerization.