由MCM-22沸石结构前驱体合成介孔材料及其催化性能的研究

实验以两步晶化法,利用MCM-22沸石结构前驱体合成一种含介孔的催化材料,用XRD、N_2吸附-脱附、~(27)Al MAS NMR、NH_3-TPD对试样进行了表征。实验结果表明其孔径约为3.3 nm,比表面积为740～870m~2/g,其氢型试样除含有弱酸中心外,还含有强酸中心,总酸量为0.71～0.76 mmol/g。在115℃条件下,试样用于催化2,4-二叔丁基苯酚与叔丁基醇烷基化反应时,2,4-二叔丁基苯酚的转化率约为22%,2,4,6-三叔丁基苯酚的选择性约为49%,其催化活性高于微孔沸石Hβ和常规介孔分子筛HMCM-41。

SYNTHESIS AND CATALYTIC PERFORMANCES OF MESOPOROUS MATERIAL FROM PRECURSOR OF MCM-22 ZEOLITE

Mesoporous catalytic materials were synthesized by a two-step crystallization process with the precursor of MCM-22 zeolite and characterized by XRD, N_2 physical adsorption-desorption, ~(27)Al MAS NMR, and NH_3 - TPD methods. The results demonstrated that the pore diameter of the sample was 3. 3 nm and surface area was 740 - 870 m~2/g. H-form samples had both strong and weak acid sites, with the total acid amount of about 0. 71 -0. 76 mmol/g. The samples were used to catalyze the alkylation of 2,4-tert-butylphenol with tert-butylalcohol at 115℃ , with the conversion of 2,4-ditert-butylphenol and the selectivity to 2,4,6-tritert-butylphenol being about 22% and 49%, respectively. The catalytic activity was higher than microporous zeolite Hβ and traditional mesoporous molecular sieve A1MCM-41.