(1. 福州大学石油化工学院，福州 350108；
2. 澳大利亚科廷大学西澳矿业学院，西澳大利亚 6102)
摘 要: 针对当前由粉煤灰制备氧化铝成本高、除杂难度大等问题，提出了以富铝粉煤灰为原料的硫酸加压浸取、钾明矾结晶净化、钾明矾热解生产氧化铝的新技术路线，并对关键环节进行了热力学分析和试验验证。结果表明：该技术路线可实现低物料消耗、低能耗浸出，高效地解决从复杂硫酸盐溶液中分离铝的问题，并实现了反应过程所需硫酸、硫酸钾以及过量硫酸的循环利用。通过与传统拜耳法生产氧化铝工艺对比，本文所述技术路线理论能耗和物料消耗更低、原料来源更广泛，展现了高硅富铝粉煤灰酸法生产氧化铝新工艺的广阔应用前景。
关键字: 粉煤灰；酸法；钾明矾；热解；氧化铝
（1. College of Chemical Engineering, Fuzhou University, Fuzhou 350116, China;
2.Western Australian School of Mines: Minerals, Energy and Chemical Engineering, Curtin University, WA, 6102, Australia）
Abstract:Theproduction of aluminium oxide from coal flay ash, an aluminum-rich and silicate-based solid waste, has been found uneconomic, particularly due to the great challenge for impurity removal.The present study proposes a new process to recover aluminum oxide from coal fly ash using pressure leaching with sulfuric acid, followed by crystallization and pyrolysis of potassium-alum. The thermodynamic and experimental analyses results show the feasibility of obtaining metallurgical-grade aluminum oxide using the new process, with low reagent and energy consumption. In the process, the separation of aluminum from the complicated sulfate leachate can be achieved efficiently. The excess sulfuric acid, potassium sulfate and oxy-sulfide (obtained from pyrolysis) can all be recycled for reused. The comparisons between the new process and the traditional Bayer process indicate that the new process for aluminum oxide production from aluminum-rich and silicate-based materials has a wide application.
Key words: coal fly ash; acidic method; potassium alum; pyrolysis; aluminum oxide
