Al-ITQ-13分子筛的酸处理及其在苯-甲醇烷基化中的应用

Treatment of Al-ITQ-13 molecular sieve by acid and application in alkylation of benzene with methanol

以硅溶胶、九水硝酸铝、氧化锗为原料直接合成了Al-ITQ-13分子筛原粉,并利用0. 01 mol/L的盐酸对分子筛原粉进行脱锗处理。利用XRD、SEM、N2吸附-脱附、NH3-TPD、ICP-OES和IR等方法对酸处理前后的分子筛进行表征,并将其应用于苯-甲醇烷基化反应中,考察其催化性能。结果表明,在酸处理温度为120℃时,分子筛的骨架不受影响,比表面积和孔体积最大,脱锗率为22. 72%,苯的转化率为59. 3%,比处理前提高了7. 1%。

Al-ITQ-13 molecular sieve raw powder is directly synthesized from silica gel,aluminum nitrate nonahydrate and germanium oxide,then treated with 0.01 mol·L-1 hydrochloric acid.The samples are characterized by means of XRD,SEM,N2 adsorption-desorption,NH3-TPD,ICP-OES and IR,and their catalytic performances are evaluated in the alkylation of benzene with methanol.It is verified that the backbone of molecular sieve will not be affected,and the specific surface area and pore volume of the treated molecular sieve will reach the largest when the molecular sieve raw powder is treated by hydrochloric acid at 120℃.By using the treated molecular sieve,the removal rate of germanium can reach about 22.72%and the conversation of benzene can reach 59.3%which is 7.1 percentage points higher than that by using untreated samples.