正十六烷在Pt/SAPO-11上的临氢异构反应

Hydroisomerization of n-hexadecane on Pt/SAPO-11 catalyst

制备了Pt/SAPO-11双功能催化剂,采用XRD、NH3吸附-脱附等分析方法对制备的催化剂进行表征,对正十六烷在Pt/SAPO-11双功能催化剂上的临氢异构反应进行了研究,考察了氢分压、反应温度、氢烃体积比和液态空速等反应条件对催化剂性能的影响,探讨了催化剂的焙烧温度和还原温度对催化剂性能的影响。表征结果显示,Pt/SAPO-11双功能催化剂的孔结构对性能影响较小,而催化剂的弱酸性有利于异构选择性。实验结果表明,氢分压高对于烷烃临氢异构反应活性有不利的影响,而反应温度的选择需兼顾异构活性及选择性,氢烃体积比对反应无明显影响;催化剂的焙烧温度、还原温度对催化剂的活性和异构选择性有较大影响,在适当的温度范围内制备的催化剂有较好的活性和选择性。

Pt/SAPO-11 bifunctional catalysts have been prepared and characterized by XRD and NH3 adsorption-desorption.Hydroisomerization of n-hexadecane on Pt/SAPO-11 has been investigated.The effects of hydrogen pressure,reaction temperature,volume ratio of hydrogen to alkane and LHSV on catalytic performance have been studied.The relationship of catalyst performance and preparation conditions,such as calcination temperature and reduction temperature has been discussed.It is found that the pore structure of Pt/SAPO-11 has little effect to the performance of the catalyst.The weak acidity of the catalyst is favorable to achieve high hydroisomerization selectivity.It is shown that the high hydrogen pressure has an adverse effect on the hydroisomerization activity of alkane,the reaction temperature is determined under condition that both selectivity and activity of isomerization are taken into consideration,and the ratio of hydrogen to alkane has nearly no effect on the reaction.The temperatures of calcination and reduction of catalysts have great effect on the reaction activity and hydroisomerization selectivity.In the preferential temperature range,the catalysts produced thereby have better activity and selectivity.