(東北大學(xué) 材料冶金學(xué)院，沈陽(yáng) 110004)
摘 要: 粉煤灰酸法提取氧化鋁后渣中二氧化硅含量接近85%，是制備硅酸鈉水玻璃的優(yōu)質(zhì)原料。提出了在常壓下用高濃度堿液浸出粉煤灰提鋁渣中二氧化硅的工藝；研究了二氧化硅在濃堿體系中的浸出行為。實(shí)驗(yàn)結(jié)果表明，在溫度為110 ℃、堿濃度為50%、液固比為2.2׃1、時(shí)間為60 min條件下反應(yīng)最佳，堿浸渣的XRD分析表明，對(duì)酸渣進(jìn)行二次堿浸后，渣中SiO2浸出完全，主要物相為鈉硅渣和碳酸鹽。
關(guān)鍵字: 粉煤灰；渣；浸出；濃堿；硅酸鈉；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
