(东北大学 材料冶金学院，沈阳 110004)
摘 要: 粉煤灰酸法提取氧化铝后渣中二氧化硅含量接近85%，是制备硅酸钠水玻璃的优质原料。提出了在常压下用高浓度碱液浸出粉煤灰提铝渣中二氧化硅的工艺；研究了二氧化硅在浓碱体系中的浸出行为。实验结果表明，在温度为110 ℃、碱浓度为50%、液固比为2.2׃1、时间为60 min条件下反应最佳，碱浸渣的XRD分析表明，对酸渣进行二次碱浸后，渣中SiO2浸出完全，主要物相为钠硅渣和碳酸盐。
关键字: 粉煤灰；渣；浸出；浓碱；硅酸钠；二氧化硅
（School of Materials and Metallurgy, Northeastern University, Shenyang 110004, China）
Abstract:The concentration of SiO2 in the residue of fly ash detached Al2O3 was 85%. It is the excellent material to prepare Na2SiO3. A new method of leaching SiO2 from the residue was studied in atmosphere and highly concentrated alkali solution. The optimum conditions are: reaction temperature 110 ℃, alkali concentration 50%, ratio of liquid to ore 2.2׃1 and reaction time 60 min. The XRD was used to analyze the residue after alkali leaching. The result shows that SiO2 is leached completely and the main phases are Na-Al silicate slime and carbonate.
Key words: fly ash; residue; leaching; highly concentrated alkali solution; Na2SiO3; SiO2
