摘要
盐类和分子筛混合加热,即使盐类的离子直径比分子筛有效孔径稍大,盐类仍可在分子筛内孔和内表面实现分散.例如,Cl^-直径为3.6(?)比3A分子筛孔径大,I^-直径为4.4(?)比3A和4A分子筛孔径大,加热这些碱全属氯化物或碘化物与分子筛的混合物,Cl^-和I^-离子仍可“挤”过通过实现分散。这可由离子和孔道的非刚性来解释。但如果盐类离子比分子筛孔径大得多,例如,邻苯二甲酸氢钾的负离子直径为7.9(?)比3A、4A和5A分子筛孔径大得多,即使加热也不能实现分散,表现出离子筛效应,但对于13X分子筛(孔径为8-9(?))仍可实现分散。
A salt can jostle into zeolite internal pores by heating the mixture of the salt and a zeolite even though the salt ion is a little larger than the zeolite channel. For example, Cl^-(3.6(?)) can disperse into 3A zeolite pores and I^-(4.4(?)) can go into 3A and 4A zeolite pores. This may be explained by nonrigility of atoms of salts and zeolite channels. However, C_6H_4(CO_2H) CO_2^-(7.9(?)) couldn't disperse into 3A, 4A and 5A zeolite internal pores because it is greatly larger than the channels of 3A, 4A and 5A zeolites, but it could disperse into 13X zeolite pores(8-9(?)).
基金
国家自然科学基金
