Lithosite (-LIT) type aluminosilicate zeolites were successfully synthesized, for the first time, by solvothermal treatment of low-silica zeolite powders. The starting materials comprised H-Y zeolite samples having different SiO _2/Al _2O _3 ratios, together with NH _3 ~+-exchanged chabazite and NH _3 ~+-exchanged phillipsite. The low-silica zeolite powders were dispersed in alcohol containing dissolved KOH, and the mixture was solvothermally treated at 200-250 °C for 15-120 h without stirring. The crystal structure of the obtained sample was analyzed by the Rietveld method which indicated it to be single phase -LIT zeolite (monoclinic, space group P2 _1, a = 1.513 nm, b = 1.023 nm, c = 0.842 nm, β = 89.99°). The scanning electron microscopy images show that the obtained product consists of blade-like particles. The SiO _2/Al _2O _3 ratios of the -LIT samples varied from 4.0 to 6.7 based on the composition of the starting materials. The zeolite pores were hydrophilic in nature; however, potassium cations contained in the micropores were hardly exchanged at room temperature. Furthermore, Co-substituted -LIT zeolite was also successfully synthesized by a similar method as that used for -LIT-type aluminosilicate zeolite, using Co ~(2+)-exchanged H-Y zeolite as the starting material.
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