摘要
In this paper, desilification for high-aluminium coal fly ash in alkaline media under pressure was reportedto improve the efficiency of sodium leaching. Factors such as the alkaline quantity, reaction temperature, time andliquid-to-solid ratio on desilification were studied in detail. At the same time, the kinetics of desilification were ana-lysed to further reveal the leaching mechanism. The results showed that the alkaline quantity, reaction temperatureand liquid-to-solid ratio had significant effects on the desilification efficiency with increasing reaction time. Themaximum SiO2 leaching rate was 65.78% under the optimal experimental conditions. According to the shrinking coremodel, the process of leaching is controlled by surface chemical reactions in the earlier stage and diffusion of thesolid layer in the later stage.
