Fine Al2O3 Powder Produced by Radio-Frequency Plasma From Aluminum Dross

Aluminum dross is generated as a byproduct in aluminum production or aluminum recycling processes. The major chemical composition of aluminum dross is aluminum element, and it has potential as a starting material to produce high-purity fine aluminum oxide (Al₂O₃) powder. In this paper, a radio frequency (RF) plasma synthesis system is designed as a high-temperature source to produce Al₂O₃ from aluminum dross. As the RF power increased to 3.5 kW, the color of Al₂O₃ ceramic powder is transferred to pure white. X-ray diffraction analysis results showed that the synthesized powder comprises of corundum (α-Al₂O₃). The particle size distribution analysis results showed d50 was 8 μm. The purity of the synthesized Al₂O₃ powder is 99.95%. In general, the 92% Al₂O₃ can be applied as commercial product. The quality of Al₂O₃ powder synthesized in this paper is exceeded this level and has higher value as they are sold in the market. The RF plasma technique developed is proven suitable for treating aluminum dross and converting it into a marketable product.