氧化铝载体孔结构对长链正构烷烃(C_(16)～C_(19))脱氢Pt-Sn-K/Al_2O_3催化剂性能的影响

通过N_2吸附-脱附法对4种Al_2O_3载体进行孔结构表征,采用等体积真空浸渍法制备Pt质量分数0.5%的Pt-Sn-K/Al_2O_3催化剂,以直链烷烃C_(16)~C_(19)脱氢反应为探针,考察Al_2O_3载体孔结构对催化剂脱氢性能的影响。结果表明,催化剂载体的孔容、平均孔径和比表面积之间存在相互制约的关系。载体孔容和平均孔径大,则其比表面积相对较小。对于直链烷烃C_(16)~C_(19)脱氢催化剂,较大孔容、孔径和一定比表面积的Al_2O_3载体为最佳,孔容和孔径较小的催化剂脱氢活性和稳定性较差。

Effects of pore structure of alumina supports on the performance of Pt-Sn-K/Al2O3 catalysts for long chain n-paraffin (C16-C19) dehydrogenation

The pore structure of alumina supports were characterized by nitrogen adsorption-desorption method.Pt-Sn-K/Al₂O₃ catalysts with Pt mass fraction of 0.5% were prepared by using vacuum impregnation method.The influence of the pore structure of Al₂O₃ supports on the catalytic performance of the catalysts was investigated by using long chain n-paraffinC₁₆-C₁₉ dehydrogenation as the probe reaction.The results showed that the pore volume,average pore size and specific surface area of the supports had the mutual restriction.When the pore volume and size of the support were large,its surface area was relatively small.Al₂O₃ supports with larger pore volume and pore size, and a certain surface area were suitable for the catalysts for long chain n-paraffinC₁₆-C₁₉ dehydrogenation.The catalysts with smaller pore volume and pore size possessed the relatively low dehydrogenation activity and stability.