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以四乙基氢氧化铵为模板剂,研究了低模硅比条件下β沸石的合成规律.发现晶种和模板剂之间存在明显的协同导向作用.但碱源对晶种和模板剂的导向作用以及β沸石产物有明显影响.以NaOH为碱源时,晶种的作用主要是缩短晶化诱导期,而模板剂的作用主要是提高晶体生长速率.以氨水为碱源时,晶种和模板剂对缩短诱导期和提高晶体生长速率都有贡献.总的来说,以NaOH为碱源时凝胶的晶化速率较快.但是β沸石产物的硅铝比很低,且晶粒度较大,团聚体比较紧密.相比之下,以氨水为碱源有利于提高β沸石的硅铝比.同时,所合成的β沸石晶粒度小,外表面积大,团聚体中介孔较多.
With tetraethylammonium hydroxide as a template, the synthesis of β zeolite with low ratio of silicon to silicon was studied, and it was found that there was a clear synergistic orientation between the seed crystal and the template. However, Orientation and β zeolite products have a significant impact.With NaOH as the alkali source, the role of seeds is to shorten the crystallization induction period, and the role of the template is mainly to improve the crystal growth rate.With ammonia as the source, the seed And templating agents both contribute to shortening the induction period and increasing the crystal growth rate.Generally, the crystallization rate of the gel is faster with NaOH as the base source.But the silica-alumina ratio of the zeolite beta is very low, In contrast, the use of ammonia as the alkaline source is beneficial to improve the Si-Al ratio of zeolite beta.At the same time, the β zeolite synthesized has small grain size, large surface area and more aggregate pores many.