以粉煤灰为原料,采用两步法合成了亚微米NaA型沸石(Na12[Al12Si12O48].27H2O)。研究了晶化时间和NaOH溶液浓度对合成亚微米NaA型沸石的纯度、结晶度和粒度的影响。结果表明:晶化时间将影响NaA型沸石的纯度和结晶度;NaOH溶液浓度主要影响产物的粒径大小和粒度分布范围。通过优化合成条件,在5mol/L和6.67mol/LNaOH溶液浓度的条件下,由粉煤灰制备的硅铝凝胶,在100℃分别晶化4h和3h可合成骨架结构完好,结晶度高的亚微米NaA型沸石。合成的亚微米NaA型沸石的平均粒径分别为450nm和250nm,粒径分布范围(sizespan,SP)分别为3.84和2.44。合成产物的NH4+和Cu2+离子交换容量随着晶粒的减小而显著增加。

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