本研究采用溶胶一凝胶法合成了成分可控、高纯和高活性的Al2O3-SiO2粉体。以工业级水玻璃为碱激发剂,将二者按照方沸石理论配比(Na:Al:Si=1:1:2)混合后制备得到Na2O-Al2O3-4SiO2-8H2O地质聚合物凝胶体;将地质聚合物凝胶体在70℃烘箱中养护一定时间后脱模;研究采用x射线衍射(XRD)、扫描电镜(SEM)和BET等对产物进行了表征,无模板剂的条件下利用240℃水热反应制备了50~1200μm不同粒径的方沸石晶体,并初步探讨了大尺寸方沸石晶体的形成机理。
The ingredient controllable, high-purity, high reactive Al2O3-SiO2 powders were synthesized by sol-gels. Using the industrial grade sodium silicate Na2SiO3·mH2O as alkali activator, the Na2O-Al2O3- 4SIO2-8H2O geopolymer gels were prepared from the Al2O3-SiO2 powders and sodium silicate according to the analcime zeolite composition(Na: AI: Si = 1: 1:2). Then the reaction products were cured in the oven 70℃ to form the geopolymer gels. The controllable 50-1200μm different particle size of analcime crystals through hydrothermal method at 240℃, especially without organic structure-directing agents (SDAs) were synthesized. The products were analyzed by X-ray diffraction, SEM and BET. The formation mechanism of large analcime crystals was also discussed.