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采用低温晶化法一步合成了纳米硅铝介孔分子筛(记为Z-1),并通过XRD、BET、N2吸/脱附曲线和TEM等手段对其结构性质进行了表征.结果表明:所合成的分子筛具有类似MCM-41的六方结构,较好的介孔特征,孔分布狭窄,纳米级晶粒(40～50nm).用氨气程序升温脱附(NH3-TPD)法测试了其酸强度;并采用脉冲法,以异丙苯和1,3,5-三异丙苯的催化裂化为探针反应,考察了该分子筛的催化裂化性能和水热稳定性.Z-1与后嫁接法制得的AlMCM-41相比,呈现出较高的催化活性、选择性和蒸气稳定性.
The nanosilica-mesoporous mesoporous molecular sieves (denoted as Z-1) were synthesized by one-step crystallization at low temperature, and their structural properties were characterized by XRD, BET, N2 adsorption / desorption curves and TEM etc. The results show that The synthesized molecular sieve has a hexagonal structure similar to MCM-41, with good mesopore characteristics, narrow pore distribution and nanometer scale grains (40-50nm). Its acidity was tested by NH3-TPD method The catalytic cracking performance and hydrothermal stability of the molecular sieve were investigated by pulse method with the catalytic cracking of cumene and 1,3,5-triisopropylbenzene as the probe reaction. Compared with the AlMCM-41 obtained by the method, the catalyst exhibited higher catalytic activity, selectivity and vapor stability.