Studies on the AlCl 3/dimethylsulfone (DMSO 2) electrolytes for the aluminum deposition processes

Abstract

This paper presents a study of the aluminum deposition processes in dimethylsulfone (DMSO 2)-based electrolytes. The electrical conductivities of the AlCl 3/DMSO 2 electrolytes were investigated as a function of temperature (70–180 °C) and molar ratio of AlCl 3 to DMSO 2 (from 0.1:1 to 0.8:1). The results show that the temperature-dependent conductivities of the electrolytes fit well with the Vogel–Tamman–Fulcher (VTF) equation. The optimum operating conditions for the electrodeposition of aluminum from AlCl 3/DMSO 2 electrolytes were determined based on the studies of the effects of current density, electrolyte temperature and the molar ratio of AlCl 3 to DMSO 2 on the quality of the deposited coatings. Dense, bright and adherent aluminum coatings were obtained in AlCl 3/DMSO 2 electrolytes over a wide range of temperatures (110–150 °C) and current densities (5 to 20 A dm − 2 ). The preliminary results from Al refining experiments showed that Al alloy can be purified via electrolysis in 0.2:1 AlCl 3/DMSO 2 at 130 °C with a current density of 10 A dm − 2 .