Extraction of Aluminum from Coal Combustion Fly Ash
Coal combustion fly ash (CFA) is a by-product generated from coal combustion during the generation of electricity. A part of CFA with particle size less than 45 μm has been used as construction and filling materials. However, majority of them, 2,700 million tons, has been dumped in ash-bin and remained unused in China due to high carbon content and low reactivity. It is hence necessary to investigate the potential applications of CFA. The statistical average Al2O3 content of CFA is around 30 wt.% in China. This research studied the feasibility of aluminum extraction from CFA activated at lower temperature than 1000 ℃. The mineralogy and chemical properties of CFA have been characterized. The CFA was mixed with required amount of chemical additive and subjected to high temperature sintering from 800 to 1100 ℃ for one hour. The extraction properties under 20 wt.% hydrochloric acid solution and micro-structures of sintered samples have been studied. The results showed that the extraction of aluminum increased with the sintering temperature. However, the increase in the aluminum extraction decreased when the sintering temperature was higher than 900 ℃ at which 85 wt.% of alumina in the CFA can be extracted. The particle sizes of ground sintered samples had little effect on the extraction of aluminum. The aluminum extraction increased with the extraction temperature and time. Anorthite (Ca(Al2Si2O8)) is the main product in the sintered samples and increased with sintering temperature.
Coal fly ash Aluminum Leaching Sintering
H.M. Zhou X.C. Qiao J.G. Yu
School of Resource and Environmental Engineering East China University of Science and Technology, Meilong Road 130, Shanghai, China, 200237
国际会议
The 12th Asian Pacific Confederation of Chemical Engineering Congress(第十二届亚太化工联盟大会暨化工展览会)
大连
英文
2008-08-04（万方平台首次上网日期，不代表论文的发表时间）