不同类型碱对AlMCM-41分子筛合成及催化性能的影响

Effect of Different Alkalis on the Synthesis and Catalysis Performance of AlMCM-41 Molecular Sieve

用无机碱NaOH和有机碱TEAOH合成了不同硅铝比的AlMCM -4 1介孔分子筛 ,通过XRD、SEM、TEM、NH3-TPD、吡啶吸附和N2 等温吸附进行了表征。研究表明 ,使用TEAOH适合于合成低硅铝比的AlMCM -4 1分子筛 ,而使用NaOH合成高硅铝比的AlMCM -4 1分子筛 ,所得产物的有序程度较高。由TEAOH合成的AlMCM -4 1分子筛的比表面积、孔径、总酸量和B酸量均略大于由NaOH合成的试样 ,而且对异丙苯裂解和苯与

AlMCM-41 mesoporous molecular sieves with various Si/Al mol ratios were synthesized by using inorganic and organic alkalis,NaOH and tetracthyl ammonium bydroxide (TEAOH),and were characterized by XRD,SEM,TEM,TPDA,IR spectra of pyridine adsorption and N 2 isothermal adsorption.TEAOH is suitable for the synthesis of AlMCM-41 with lower Si/Al mol ratio,while NaOH is suitable for preparing ordered mesoporous AlMCM-41 with higher Si/Al mol ratio.In comparison with the samples prepared by NaOH,the mesoporous materials prepared by TEAOH have larger surface,larger pore diameter,more total acid content and Brnsted acidity,and also show higher catalytic acitivity for cracking of cumene and alkylation of benzene with 1-dodecene