【摘要】 制备了一系列金属离子改性的SO42-/ZrO2固体超强酸(SZ)。用N2吸附比表面积测定、X射线衍射、透射电子显微镜、扫描电子显微镜、差热分析等方法对固体超强酸进行表征。以正己烷的裂解为探针反应,考察了固体超强酸催化剂的催化活性和乙烯选择性。实验结果表明,不同金属离子改性的SZ均为纳米粒子(粒径小于40nm),但其催化剂的催化活性不同。金属离子和SO42-的共同作用使得ZrO2由四方晶形向单斜晶形转化的温度升高,晶粒粒度减小,比表面积增大,催化活性提高。催化剂催化正己烷裂解的活性由高到低的顺序为:N i/SZ>A l/SZ>Sn/SZ>SZ>Ag/SZ。更多还原

【Abstract】 A series of sulfated zirconia—SO^2-₄/ZrO₂（SZ）modified by doping metal ions,such as Ni²⁺,Al³⁺,Sn⁴⁺,were prepared by impregnation of zirconium hydroxide in H₂SO₄ and different metal ion solutions.The solid nanosuperacids were characterized by BET,XRD,TEM,SEM,DTA and chemical method.Activities and ethylene selectivities of catalysts were evaluated using cracking of n-hexane as probe reaction.SO^2-₄/ZrO₂ modified by doping different metal ions behaved differently and all catalysts particles were in nano-size（<40nm）.Joint effects of metal ions and SO^2-₄ increased crystal transition temperature of ZrO₂ from tetragonal to monoclinic.At the same time,crystallite size was decreased and specific surface area increased significantly.Activity of SO^2-₄/ZrO₂ catalysts modified by various metal ions in n-hexane cracking was in order of Ni/SZ>Al/SZ>Sn/SZ>SZ>Ag/SZ.更多还原