由稻壳灰合成P型分子筛

摘要

Synthesis of zeolite P by hydrothermal method using rice husk ash as silicon source was optimized. It was found that the maximum calcium exchange ability of zeolite P is 305.4 mg/g when synthesis was carried out at 1.2 of n(Na2O)/n(SiO2) molar ratio, 7.0 of n(SiO2)/n(Al2O3) molar ratio, 25 of n(H2O)/n(Na2O) and 85℃ of crystallizing temperature for 10 h. analysis by X ray diffraction and SEM suggested the better characteristic peak and the narrower grain-size distribution.%以农业废弃物稻壳经酸化处理、焙烧所得的稻壳灰为硅源,通过水热法未经老化过程及添加晶种直接合成了P型分子筛.采用钙交换能力、XRD和SEM对所合成产物的晶体结构、表面形貌和离子交换性能进行了表征.研究结果表明,该工艺合成P型分子筛的最佳条件为:n(Na2O)/n(SiO2)=1.2,n(SiO2)/n(Al2O3)=7.0,n(H2O)/n(Na2O)=25,于85℃反应10 h,在此条件下合成的P型分子筛产品具有较高的结晶度,无杂相且晶粒精细,其钙交换能力达到每克P型分子筛可吸收305.4 ng碳酸钙.