Thesis (M.Eng.)--Chulalongkorn University, 2001

The optimum conditions of synthesis of zeolite beta from lignite fly ash were investigated. The parameters studied were stirring and aging temperature, TEAOH/SiO[subscript 2] mole ratio and Si/Al atomic ratio. The temeratures of stirring stage effected on the crystallinity of zeolite beta synthesized from lignite fly ash. During the crystallization, the temperature of aging with stirring and crystallization without stirring stage should be the same temperature since changing of the temperature effected on distribution of crystal size. The optimum aging and crystallization temperature were 140 ํC. The optimum TEAOH/SiO[subscript 2] mole ratio was 0.5 and Si/Al atomic ratio was 50. This condition gave the highest crystallinity of zeolite beta synthesized from lignite fly ash (about 98% crystallinity) and BET surface area about 630 m[superscript 2]/g and uniform crystal size of 0.25 micrometre. At this condition, the characteristics of zeolite beta synthesized from lignite fly ash are not much different from commercial zeolite beta which has BET surface area and average crystal size about 0.5 micrometre and 700 m[superscript 2]/g, respect ively. Furt hemore, result of methanol conversion reaction is not quite different. However, there were Fe[subscript 2][O[sbscript 700 %[superscript 2] respectively. Furthemore, result of methanol conversion reaction is not quite different. However, there were Fe[subscript 2]O[subscript 3] and other metal oxides presented in obtained crystal which effect to the product selectivity of methanol conversion reaction.