Effect of Different Reducing Agents on Silicon-Aluminum Alloy Prepared from Coal Fly Ash

Abstract The effect of charcoal and coke as reducing agents on the preparation of silicon-aluminium alloy from coal fly ash was studied. X-ray diffraction (XRD) analysis of the reduction products under the action of two reducing agents was carried out. The results showed that SiC and Al 2 SiO 5 were formed in the reduction products with charcoal or coke as reducing agent at 2073K, and impurity Fe 2 SiO 4 was formed in the products with coke as reducing agent. At 2173K, when charcoal or coke was used as reducing agent, the same kinds of reduction products were SiC, Si, Al, Al 2 O 3 and Al 4.5 FeSi, and the intensity of diffraction peaks of Al and Si in reduction products by charcoal as reducing agent was higher than that of Al and Si in reduction products using coke as reducing agent. At 2273K and charcoal as reducing agent, the reduction products of coal fly ash were Al, Si, SiC and Al 4.5 FeSi. When coke was used as reducing agent, the products of reduction coal fly ash were Si, FeSi, SiC, Al and Al 4.5 FeSi. In this study, the reduction ability of charcoal is better than that of coke at different temperatures, and the reduction effect of silicon-aluminium alloy prepared by charcoal reduction coal fly ash is the best at 2273K for heating 30 minutes.