摘要
以天然沸石作为硅铝源合成分子筛有着原料丰富、成本低廉等特点.近年来,用天然沸石作为原料合成分子筛的工作已有报道.但合成体系均为碱性介质,并有模板剂.Guth等在非碱体系合成了ZSN-5分子筛.李赫咺等采用直接法,以水玻璃和硫酸铝为原科,成功地合成了ZSM-5分子筛,但在非碱体系和直接法用天然沸石合成ZSM-5分子筛的工作尚未见报道.作者以天然沸石矿为原料,首次采用水热晶化法在非碱体系和直接法合成出ZSM-5分子筛,并对其结构和性能进行了考察.
By using natural zeolite clinoptilolite as precursor, ZSM-5 molecular sieves were hydrothermally sythesized in both alkaline and non-alkaline media in the presence of template tetrapropylammonium bromide, and in alkaline medium in the absence of template. The structure and the crystal morphology of the synthesized ZSM-5 were studied by means of XRD, SEM and IR techniques. The results of XRD and SEM show that the synthetic samples are pure phase of ZSM-5 molecular sieve and they have good adsorption properties and good catalytic performance. IR study proves that the samples have both Bronsted acid center and Lewis acid center.
