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采用HCl溶液和/或水热处理HEU-1分子筛,利用X射线衍射、N2吸附-脱附、X射线荧光光谱、NH3程序升温脱附、吡啶吸附傅里叶变换红外光谱和铝固体核磁共振等对脱铝处理的HEU-1分子筛进行了表征,并考察了脱铝HEU-1分子筛上正己烷的催化裂解性能.结果表明,采用HCl溶液处理HEU-1分子筛,能有效脱除非骨架铝,可调变样品的弱酸中心;而水热处理HEU-1分子筛,能有效脱除骨架铝,可调变样品的强酸中心.水热处理和HCl溶液处理有效结合可以达到同时调变HEU-1分子筛的酸类型和酸密度的目的.脱铝HEU-1分子筛上正己烷催化裂解反应结果表明,氢转移反应被明显抑制,丙烯选择性提高.600°C水热处理后再用HCl溶液处理的HEU-1分子筛于625°C反应时丙烯选择性由未改性的21.9%提高到35.2%,活性稳定性也由不足10h提高到40h.
HEH-1 zeolites were treated with HCl solution and / or hydrothermally. The structures were characterized by X-ray diffraction, N2 adsorption-desorption, X-ray fluorescence spectroscopy, NH3 temperature programmed desorption, pyridine adsorption Fourier transform infrared spectroscopy and aluminum solid-state NMR The dealumination of HEU-1 zeolite was characterized and the catalytic cracking performance of n-hexane on the dealuminated HEU-1 zeolite was investigated.The results showed that the treatment of HEU-1 molecular sieve with HCl solution can effectively remove the non-framework aluminum, The hydrothermal treatment of HEU-1 molecular sieve can effectively remove skeleton aluminum, and can adjust the strong acid center of the sample.HRP and HCl solution can be effectively combined to adjust the acid type of HEU-1 molecular sieve The results showed that the hydrogen transfer reaction was obviously inhibited and the selectivity of propylene increased.After the hydrothermal treatment at 600 ° C, the HEU-1 molecular sieve treated with HCl solution in 625 The selectivity of propylene increased from 21.9% unmodified to 35.2% at ° C, and the stability of activity increased from less than 10h to 40h.