采用毛细管式微通道反应器,研究了清液合成体系中流动法条件下亚微-纳米级NaA和Silicalite-1沸石分子筛的合成,考察了合成温度、陈化时间、停留时间等条件对其粒径分布和形貌的影响.通过XRD、TEM、DLS进行表征,分析结果表明:降低合成温度,增加陈化时间和减少停留时间都能使分子筛产品的粒径变小.经优化的合成条件分别是:当合成温度为70℃、陈化时间为72h、停留时间为5.8h时,可获得平均粒径约为100nm的NaA分子筛,且晶粒均匀呈椭球形;合成温度为98℃、陈化时间为24h、停留时间为10b时,可获得平均粒径约为80nm的Silicalite-1分子筛.该方法比常规合成釜内静态法制备的沸石粒子小而均匀,且合成过程简单、连续.
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