Pt-S2O28-/ZrO2-A12O3(Pt-SZA-X) solid superacid catalysts were prepared by microemulsion method and characterized by XRD,BET,FT-IR,TPR and TEM.The effects of calcination temperatures on the isomerization performance were studied by using n-pentane isomerization as a probe reaction.It was found that the calcination temperature has less influence on the reduction temperature of the Pt-SZA-X,but the S content over catalyst decreased with increasing calcination temperature.The O =S =O structure formed at calcination temperature range of 600 to 650 ℃ and the combination between of S and catalyst support was relatively stable.The pure monoclinic phase of ZrO2 were observed with sample calcined at 650 ℃.When the calcination temperature is higher than 650 ℃,the specific surface area decreases rapidly and the loss of S6+ on the surface of catalyst is seriously.Among the catalysts obtained at various calcination temperatures,the catalyst calcined at 650 ℃ has appropriate amount of superacid sites and surface area and the highest isomerization activity.At reaction temperature of 230 ℃,pressure of 2.0 MPa,hydrogen/hydrocarbon molar ratio of 4 ∶ 1 and mass hourly space velocity of 1.0 h-1,the isopentane yield is 60.8％.%过微乳液法负载Pt制备了Pt-S2O2-8/ZrO2-Al2O3 (Pt-SZA-X)催化剂,并采用XRD、BET、FT-IR、TPR、TEM等手段对催化剂进行了表征.以正戊烷异构化反应为探针,考察了焙烧温度对催化剂异构化性能的影响.结果表明,焙烧温度对Pt-SZA-X的还原温度影响不大,但催化剂表面S含量随着焙烧温度的升高而下降；焙烧温度为600～650℃时形成O-S=O结构,此时S与催化剂载体结合比较稳定；焙烧温度为650℃时,可得到单一的ZrO2四方晶相,焙烧温度高于650℃时,比表面积迅速降低,催化剂表面S6+流失严重.在不同温度下焙烧得到的催化剂中,经650℃焙烧的催化剂具有适宜的超强酸位和比表面积,异构化活性最高.在反应温度为230℃、反应压力2.0 MPa、氢烃物质的量比4∶1、质量空速1.0h-1时,催化异戊烷产率达到60.8％.
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