Sustainable recycling of titanium scraps and purity titanium production via molten salt electrolysis

摘要

Titanium resources, with many outstanding properties, is abundant in the earth's crust, while large-scale application of titanium has been substantially restricted by two key challenges, i.e. high production cost and low utilization. Currently, metallurgists have paid great attention to develop a new extraction process for achieving the goal. However, the sustainable recycling of titanium currently receives far less attention. Here, we develop a molten salt electrolysis for the high-quality recycling of titanium scarps. TC4 (Ti6Al4V) scrap, as a representative titanium alloy, is selected to investigate the separation effect in the molten salt electrolysis. Remarkably, anodic dissolution of the vanadium element in the TC4 alloy could be inhibited by decreasing anodic current density. Therefore, high priced vanadium metal powder could be collected from the anodic mud. Aluminum element in the TC4 alloy anode can dissolve into electrolyte in the form of Al ions, and then remains in the electrolyte via optimizing the electrolyte contents and electrolysis parameters. Finally, high purity titanium could be collected from the cathode. Consequently, this work is significant for the titanium sustainable recirculation or even the entire titanium industry because the titanium scraps will be converted into the high-grade titanium metal and other high priced metals. (C) 2020 Elsevier Ltd. All rights reserved.