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研究了ZSM-5沸石合成过程中(类)碱金属阳离子对沸石成胶、成核及晶化过程的影响。修正了高硅晶化平衡模型;探讨了M~+离子对此配料胶体的胶粒组成和结构的影响。发现M~+离子通过沸石配料表观pH值及本身物化性质控制沸石成核。实验结果表明,因Na~+,NH_4~+离子的竞争作用,在ZSM-5与沸石合成中发生二次成核。K~+离子的存在促进了ZSM-5沸石向α-SiO_2的转变,它是水溶液结构、ZSM-5沸石结构破坏阳离子
The effects of alkali metal cations on the gelation, nucleation and crystallization of zeolites during the synthesis of zeolite ZSM-5 were investigated. The high-silica crystallization equilibrium model was modified. The effect of M ~ + ions on the micelle composition and structure of the colloidal silica was discussed. It is found that the M ~ + ions control the zeolite nucleation through the apparent pH value of the zeolite and its own physico-chemical properties. The experimental results show that secondary nucleation occurs during the synthesis of ZSM-5 and zeolite due to competition between Na ~ + and NH_4 ~ + ions. The presence of K ~ + ions promoted the transformation of ZSM-5 zeolite into α-SiO_2, which is an aqueous solution. The structure of ZSM-5 zeolite destroys the cation