Supergravity purification and regeneration of waste Al-Cu alloy

In this paper, based on the difference in melting points of different impurity phases in 2011 Al-Cu alloy, the separation law of impurity elements Fe and Pb and beneficial elements Al and Cu in the alloy was investigated with the help of the feature of enhanced filtration and separation in the supergravity field. The results show that the impurities in raw materials after the high-temperature remelting and recrystallization processes gather between the grain boundaries of the aluminum matrix. In the high-temperature supergravity field, low-melting-point impurities could be separated and removed through the pores between the grain boundaries, and when the supergravity separation time is ≥ 1 min, the Fe and Pb content no longer changes with time. Increasing the supergravity coefficient and temperature are conducive to the removal of Fe and Pb, but the recovery of Al and Cu is reduced. Taking into account the content of Fe and Pb, as well as the recovery rates of Al and Cu, the optimal parameters for the supergravity separation process are determined as follows: a supergravity coefficient of 600, a separation temperature of 610°C, and a separation time of 1 min. Under these parameters, the Fe and Pb contents are purified to 0.06% and 0.08%, respectively. The recovery rates of Al and Cu recoveries are 95.64% and 67.90%, respectively, and the scrap Al -Cu alloy in the total percentage of Al and Cu from 97.91% to 99.72%.