硅源与硅含量对合成的SAPO分子筛催化正十二烷异构化性能的影响  

Effects of Si Source and Si Content on the Calystic Performance of Pt/SAPO-11 for Hydroisomerization of n-Dodecane

作　　者：汪哲明[1] 田志坚 林励吾 马静萌[1] 

机构地区：[1]中国石油化工股份有限公司上海石油化工研究院,上海201208 [2]大连化学物理研究所天然气转化与应用研究室,大连116023 [3]催化基础国家重点实验室,大连116023

出　　处：《化学反应工程与工艺》2008年第3期199-203,共5页Chemical Reaction Engineering and Technology

摘　　要：利用非水法合成了 SAPO-11分子筛。并采用 X 射线衍射(XRD)、能量色散型 X 荧光光谱仪(XRF)、扫描电子显微镜(SEM)和氨-程序升温脱附实验(NH_3-TPD)等手段表征了催化剂的物化性能.考察了硅源与硅铝比对 SAPO-11分子筛的正十二烷异构化性能的影响.结果表明,非水法合成的SAPO-11分子筛的颗粒与水热合成的分子筛接近,但其微晶尺寸明显小于后者.采用非水合成法时,单体硅源以及较低的硅铝比(物质的量之比小于或等于0.2)有利于合成品粒小的 SAPO-11分子筛。在所有合成催化剂中,以正硅酸乙酯为硅源,SiO_2与 Al_2O_3物质的量之比为0.05的条件下.通过非水法制备的SAPO-11分子筛为载体制备的 Pt/SAPO-11催化剂,因具有较小的微品尺寸与适宜的酸而具有较高的正十二烷异构化收率(89.8%).The SAPO-11 molecular sieves were synthesized by aqueous and nonaqueous methods. The effects of Si sources and Si contents on the acidity and crystal size of SAPO-11 were investigated by the methods of X-ray diffraction （XRD）, X-ray fluorescence （XRF）, scanning electron microscopy （SEM）, ammonia temperature-programmed desorption （NHa-TPD） and pyridine-IR. The catalytic activities of Pt/SAPO-11 were evaluated by hydroisomerization of n-dodecane. The results showed that the sample synthesized with monomeric Si source （tetraethoxysilicane） possessed not only higher Si contents also higher acidity, compared with the sample synthesized with polymerie Si source （Silica gel）. The monomeric Si sources and low ratio of SiO2 to Al2O3 （less than 0.2） was favorable to reduce microcrystal size of SAPO-11. The Pt/SAPO-11 catalyst synthesized by nonaqueous method, using tetraethoxysilicane as Si source and with 0. 05 ratio of SiO2 to Al2O3, exhibited the highest hydroisomerization activity（89. 8%） among all the catalysts due to the small microcrystal size and mild acidity.

关 键 词：非水合成 硅源 磷酸硅铝分子筛 临氢异构化 

分 类 号：TQ426.94[化学工程]