钙助剂对PtZn/SBA-15丙烷脱氢催化剂性能的影响

摘要

考察了碱土金属钙助剂对PtZn/SBA-15催化剂丙烷脱氢性能的影响,通过XRD,BET,TG,NH3-TPD,TEM等表征手段对影响原因进行了分析.表征结果显示,锌和钙助剂的添加能够使PtZnCa/SBA-15催化剂中的铂粒子分散均匀,粒径减小,部分进入分子筛孔道内部;反应中产生的积碳主要沉积在载体表面,未覆盖催化剂活性中心.实验结果表明,PtznCa/SBA-15催化剂具有良好的丙烷脱氢性能,在反应温度为600℃的条件下,稳定反应70 h以上,丙烷转化率为40％左右,丙烯选择性约为96％.%The effects of calcium on the performance of PtZn/SBA-15 catalysts were investigated.The catalysts and carrier were characterized by XRD,BET,TG,NH3-TPD,and TEM.The results showed that part of the active components can enter the mesoporous channels of the SBA-15 carrier.And the coke produced in the reaction mainly deposits in the surface of the carrier.The experimental results showed that the PtZnCa/SBA-15 catalyst had good performance in the dehydrogenation of propane.After 70 h on stream,the propane conversion rate remains about 40％,the propylene selectivity remains about 96％ under the reaction temperature at 600 ℃.