摘要
为了实现钾长石资源的综合利用,本文提出了碳酸钠碱熔活化钾长石制备碳酸钾和4A沸石的工艺。确定了碱熔活化反应的适宜条件。碱熔焙烧活化物料经水溶碳酸化后,得到含有KHCO3的溶液和硅铝质凝胶产物,前者可以经过蒸发结晶制备碳酸钾;后者经NaAlO2,NaOH和水调整合成体系中Al2O3∶SiO2∶Na2O∶H2O的物质的量比为1∶2∶5∶185后,在45℃下老化反应0.5 h,接着在90℃下晶化9 h可制得离子交换性能优良的4A分子筛。4A分子筛的钙镁交换量分别为:296.4 mg/g和108.8 mg/g。合成4A沸石后的母液能够实现在4A分子筛制备中循环利用。
In order to achieve the comprehensive utilization of K-feldspar resources,the process of the preparation of potassium carbonate and 4A zeolite by sodium carbonate alkali fusion activation of K-feldspar were proposed.The optimum conditions of the alkali activation process were obtained.Calcined products were dissolved in water and carbonated with carbon dioxide,then the system was divided into solid and liquid phases.The liquid phase was a solution containing potassium bicarbonate,which can be used to prepare potassium carbonate by evaporation and crystallization;the solid phase was silicon aluminum gel,which can be used as the raw material of preparation of zeolite.Adding NaAlO2,NaOH and H2O to adjust the molar ratio of Al2O3∶ SiO2∶ Na2O∶ H2O about 1∶ 2∶ 5∶ 185,aging at 45 ℃ for 0.5 h,and crystallizating at 90 ℃ for 9 h,then the product was obtained.The Ca2+ and Mg2+ exchange capabilities of the product were good,about 296.4 mg/g and 108.8 mg/g respectively.The crystallization mother liquor could recycle to prepare 4A zeolite molecular sieve.
出处
《人工晶体学报》
EI
CAS
CSCD
北大核心
2013年第5期953-958,共6页
Journal of Synthetic Crystals
基金
长江学者和创新团队发展计划(IRT1059)
河北省自然科学基金(B2013202246)
关键词
钾长石
4A分子筛
碱熔活化
potassium feldspar
4A zeolite
alkali activated
