The rice husk ash collected from biomass power plants was reacted with KOH solution to obtain silica sol, which was used to synthesize ZSM-5 zeolite by hydrothermal crystallization. The effects of KOH solution concentration, reaction temperature, and reaction time on the Si dissolving rate were investigated, and the optimum parameters of alkali dissolution were obtained. The effects of template contentrations and Si/Al molar ratio on the synthesis of ZSM -5 zeolite in the complex system were also studied. The as-synthesized samples were characterized by XRD, SEM, ICP, TG-DSC and BET. The results show that the ZSM-5 crystals could be successfully synthesized in a wide range of the Si/Al molar ratio (15~2002), and the products (30≤Si/Al≤52002)had complete crystal shape, high thermal stability, large specific surface area, and its micropore size was centered at about 0.53 nm.%以电厂废弃稻壳灰为原料,通过KOH溶液水热处理制取硅溶胶,采用水热合成法制备ZSM-5分子筛.考察了KOH溶液浓度、反应温度和反应时间对Si溶出率的影响,探索出最佳碱溶工艺条件；研究了在复杂合成体系中,模板剂用量、Si/Al等因素对ZSM-5分子筛合成过程的影响；采用XRD,SEM,ICP,TG-DSC,N2吸附脱附等手段进行表征,结果表明,以电厂废弃稻壳灰为原料,在较宽Si/Al范围内(15～2002)均可合成出ZSM-5分子筛;当Si/Al为30～2002时,分子筛产物晶形较为完备,热稳定性好,比表面积较大,微孔分布集中于0.53 nm.
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