粉煤灰酸法提取氧化铝的残渣制备4A分子筛

摘要

Acid insoluble ash residue was obtained from fly ash acid –dissolving extracting alumi-na.4A-zeolite was prepared with the acid insoluble ash by alkaline -hydrothermal method .The paper also studies the preparation conditions and the product properties .The results indicate that the optimum conditions:ratio of silicon to aluminum in raw material 1.5, NaOH/fly ash acid resi-due =1 .2 , calcination temperature 600 ℃, crystal temperature 100℃, Liquid-solid ratio15 and crystal time 8 h.The products structural characterization tested by XRD , SEM, IR, TG-DSC, BET and Cation exchange capacity .Comparison with standard 4A-zeolite, the results showed that the synthetic product is the 4A-zeolite, and it has good thermal stability and high adsorption ca-pacity .%利用粉煤灰酸法提取氧化铝的残渣为原料,采用碱熔融-水热合成法进行4A分子筛的合成,并对其制备工艺条件和产品性能进行了试验研究,得到制备的最佳工艺条件为:n(SiO2)/n(Al2 O3)=1.5、m(NaOH)/m(粉煤灰酸渣)=1.2、焙烧温度为600℃、晶化温度为100℃、L/S为15和晶化时间为8 h.并对产品进行了XRD、SEM、IR、TG-DSC、BET和阳离子交换容量等表征与分析,与标准4A分子筛进行比较,结果显示所合成的产品为4A分子筛,并具有较好的热稳定性和高的交换容量.