Pt-SiW/DUSY催化剂上正庚烷临氢异构化反应的研究

STUDIES ON THE HYDROISOMERIZATION OF n-HEPTANE OVER Pt-SiW/DUSY CATALYSTS

用浸渍法制备了脱铝USY(记为DUSY)负载12-硅钨酸(SiW)和贵金属Pt的双功能催化剂。采用XRD和IR对催化剂进行了表征,并采用常压固定床反应器,考察了催化剂的正庚烷临氢异构化反应性能,与USY同时负载SiW和Pt的催化剂进行比较。结果表明,DUSY负载SiW和Pt双功能催化剂表现出较高的异构化反应活性和选择性,而以纯USY为载体的催化剂反应活性很低。当DUSY催化剂Pt负载量为1.0%(质量分数)和硅钨酸负载量为15%(质量分数),反应温度为230℃时,正庚烷转化率达到72.1%,异构化产物选择性为83.0%。

The dealuminated USY supported 12-silicotungstic acid and platinum catalysts were prepared by impregnation and characterized by XRD and IR techniques. Their catalytic behaviors were measured in the hydroisomerization of n-heptane in an atmospheric fixed-bed microreactor. Comparative investigation was also carried out over USY supported catalysts. The dealuminated USY supported 12-silicotungstic acid and Pt catalysts exhibited very high catalytic activity in this reaction with considerable selectivity to isomerized products, while only a very low activity was found for the USY supported catalyst. Over the dealuminated USY supported catalyst with the Pt loading of 1.0% （mass fraction） and H4W12O40 loading of 15% （mass fraction）, at the reaction temperature of 230℃, the conversion of n-heptane was enhanced up to 72.1% with the selectivity to isomerized products of 83.0 %.