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A method is presented for the synthesis of zeolite ZSM-2 by adding zeolite X as seeds in the synthetic mixture containing both lithium and sodium. At the presence of zeolite X seeds, highly crystalline zeolite ZSM-2 with com-position of (0.3—0.7)Li2O·(0.7—0.3)Na2O·Al2O3·(2.5—4.0)SiO2·nH2O can be obtained in a wide range of SiO2/Al2O3 ratios from 2.5 to 16, and the optimum Li2O/(Li2O+Na2O) fraction is between 0.3 and 0.7. The ZSM-2 products were characterized by XRD, SEM, IR, 29Si MAS NMR and DTA/TG analysis etc. By 29Si MAS NMR spectroscopy, it was found that ZSM-2 contained nearly equal FAU and EMT phase, and the Si/Al ratios in FAU were slightly lower than those in EMT domains in most cases. The lithium form zeolite ZSM-2 has comparable N2 adsorption capacity with LiX.
A method is presented for the synthesis of zeolite ZSM-2 by adding zeolite X as seeds in the synthetic mixture containing both lithium and sodium. At the presence of zeolite X seeds, highly crystalline zeolite ZSM-2 with com-position of (0.3- 0.7) Li2O · (0.7-0.3) Na2O · Al2O3 · (2.5-4.0) SiO2 · nH2O can be obtained in a wide range of SiO2 / Al2O3 ratios from 2.5 to 16, and the optimum Li2O / (Li2O + Na2O) fraction is between 0.3 and 0.7. The ZSM-2 products were characterized by XRD, SEM, IR, 29Si MAS NMR and DTA / TG analysis etc. By 29Si MAS NMR spectroscopy, it was found that ZSM-2 contained nearly equal FAU and EMT phase, and the Si / Al ratios in FAU were slightly lower than those in EMT domains in most cases. The lithium form zeolite ZSM-2 has comparable N2 adsorption capacity with LiX.