摘要
以正硅酸乙酯为硅源、异丙基氧锆为锆源、十六烷基三乙基溴化铵(CTEABr)为模板剂,采用原位合成法在强酸性条件下合成出具有立方相结构的SBA-1和Zr-SBA-1。采用共浸渍法制备出SBA-1和Zr-SBA-1负载Pt-H_3PW_(12)O_(40)催化剂2%Pt-30%HPA/SBA-1和2%Pt-30%HPA/Zr-SBA-1。利用XRD、FT-IR和N_2吸附-脱附手段对样品进行了表征。在微型固定床反应装置上考察了催化剂对正戊烷的异构化催化性能。并对3种不同结构的SiO_2载体(SBA-1、MCM-41、SiO_2)负载Pt-HPA催化剂的异构化催化性能进行了对比。结果表明,2%Pt-30%HPA/SBA-1催化剂表现出最高的异构化催化活性,正戊烷异构化反应终点(120 min)时,正戊烷转化率和异戊烷选择性分别为65%和96%。当向SBA-1骨架中掺杂Zr元素以后,2%Pt-30%HPA/Zr-SBA-1催化剂的异构化催化活性急剧下降,且Zr的掺杂量对催化剂活性没有显著影响。3种不同结构SiO_2载体的比表面积大小与其相应的负载Pt-HPA催化剂异构化催化活性高低顺序一致,载体比表面积大小是影响催化剂异构化催化活性高低的重要因素。
SBA-1 and Zr-SBA-1 mesoporous molecular sieves with cubic phase were synthesized in-situ under strong acid condition with tetraethyl orthosilicate as Si source, isopropyl zirconium oxide as Zr source and cetyltriethyl ammonium bromide as template. SBA-1 and Zr-SBA-1 supported Pt-H3PW12O40 （2%Pt-30%HPA/SBA-1 and 2%Pt-30%HPA/Zr-SBA-1） catalysts were prepared by co-impregnation method. XRD, FT-IR and N2 adsorption-desorption were used to characterize the relevant samples. The catalytic isomerization activities of the prepared catalysts were investigated by means of micro-type fixed bed reactor. The isomerization performance of the Pt-HPA catalysts supported on three kinds of SiO2 with different skeletal structures （SBA-1, MCM-41, SiO2 ） were compared and analyzed. The experimental results showed that the 2 %Pt-30 % HPA/SBA-1 possessed the highest catalytic activity in n-pentane isomerization, in which the n-pentane conversion and iso-pentane selectivity were 65% and 96%, respectively, at the end point of the reaction （120 min）. When the Zr was doped into the skeletal structure of SBA 1, the catalytic activity of 2%Pt-30%HPA/Zr-SBA-1 decreased evidently. But nearly no obvious effect of the doping amount of Zr on the catalytic activity was found. The sequence of the catalytic isomerization activity of the supported 2%Pt-30% HPA catalysts with different SiO2 supports was the same as that of the specific surface areas of SiO2 supports. It was inferred that the specific surface area of the support was an important factor to the catalytic isomerization activity of relevant supported catalyst.
出处
《石油学报（石油加工）》
EI
CAS
CSCD
北大核心
2011年第4期532-536,共5页
Acta Petrolei Sinica(Petroleum Processing Section)
基金
河南工业大学博士基金项目(2009BS039)资助
