Electro-deoxidation of solid chromium oxide in molten chloride salts

Gordo, Elena; Chen, George Z.; Fray, Derek J.

Abstract

Chromium is industrially produced by aluminothermic reduction of Cr 2O3 or electrodeposition from the aqueous NH 4Cr(SO4)2 solution. The former makes more a expensive product than an electrolytic method because the reductant, aluminium, is produced by electrolysis. In aqueous electrolysis, the redox recycling of the multivalent chromium species between electrodes leads to low current efficiency (∼45%) and high energy consumption (∼18.5 kWh/kg Cr). Recent reports have demonstrated that solid metal oxides can be directly electrodeoxidised or electro-reduced to the respective metals/alloys in molten salts. When electordeoxidising solid Cr2O3, less than 0.2 wt-% oxygen could be achieved in the powder product coupled with a current efficiency and energy consumption of 75% and 5 kWh/kg Cr, respectively. In this paper, the important aspects of previous work are reviewed, followed by a discussion on the mechanisms of the formation of cubic or nodular chromium powders under different electro-deoxidation conditions.

Citation

Gordo, E., Chen, G. Z., & Fray, D. J. (2005, February). Electro-deoxidation of solid chromium oxide in molten chloride salts. Paper presented at TMS Annual Meeting 2005, San Francisco, California, U.S.A

• Presentation Conference Type: Conference Paper (unpublished)
• Conference Name: TMS Annual Meeting 2005
• Start Date: Feb 13, 2005
• End Date: Feb 17, 2005
• Publication Date: Aug 16, 2005
• Deposit Date: May 25, 2020
• Pages: 641-646
• Public URL: https://nottingham-repository.worktribe.com/output/3214387