(1. School of Resources and Materials, Northeastern University at Qinhuangdao, Qinhuangdao 066004, Hebei, China；
2. Key Laboratory of Resources Cleaner Conversion and Efficient Utilization at Qinhuangdao, Qinhuangdao 066004,
Hebei, China；3. Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province,
Qinhuangdao 066004, Hebei, China；4. Key Laboratory of Advanced Metal Materials and Forming Technology
in Qinhuangdao, Qinhuangdao 066004, Hebei, China；5. Engineering and Research Institute
Co., Ltd., Northeastern University， Shenyang 110166, Liaoning, China)
Taking porous coal fly ash of a power plant in Inner Mongolia as the research object, aluminum in porous coal fly ash was extracted using sulphuric acid by hydrothermal method. Based on the composition, morphology and phase analysis of coal ash, the effects of leaching temperature, leaching time, sulfuric acid concentration and dosage of sulfuric acid on the extraction efficiency of aluminum were studied. And the phases of leaching slag were characterized using Xray diffraction (XRD). The results showed that more than 88% of Al was extracted under suitable conditions in which the temperature was 180 ℃, the leaching time was 4 h, the sulfuric acid concentration was 61% and the dosage of sulfuric acid was 3 times than the theoretical value. The technique has the characteristics of low leaching temperature, low sulfuric acid concentration and high extraction rate of aluminum, and it has practical significance for the development and utilization of porous coal fly ash.
