One-step electrochemical reduction of stibnite concentrate in molten borax

Kartal L., Daryal M. B., Kartal Şireli G., Timur S.

INTERNATIONAL JOURNAL OF MINERALS METALLURGY AND MATERIALS, vol.26, no.10, pp.1258-1265, 2019 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 26 Issue: 10
  • Publication Date: 2019
  • Doi Number: 10.1007/s12613-019-1867-9
  • Journal Name: INTERNATIONAL JOURNAL OF MINERALS METALLURGY AND MATERIALS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1258-1265
  • Keywords: molten salt electrolysis, electrochemical reduction, antimony, antimony extraction, stibnite, borax, COPPER-EXTRACTION, ANTIMONY, ELECTROLYSIS, SULFIDES, SB, DESULFURIZATION, TEMPERATURE, DEOXIDATION, TITANIUM, SULFUR
  • Istanbul Technical University Affiliated: Yes

Abstract

In this study, antimony production from a stibnite concentrate (Sb2S3) was performed in one step using a molten salt electrolysis method and borax as an electrolyte. Electrochemical reduction of the stibnite concentrate was performed at 800 degrees C under galvanostatic conditions and explained in detail by the reactions and intermediate compounds formed in the borax. The effects of current density (100-800 mA center dot cm(-2)) and electrolysis time (10-40 min) on cathodic current efficiency and antimony yields were systematically investigated. During the highest current efficiency, which was obtained at 600 mA center dot cm(-2), direct metal production was possible with 62% cathodic current efficiency and approximately 6 kWh/kg energy consumption. At the end of the 40-min electrolysis duration at 600 mA center dot cm(-2) current density, antimony reduction reached 30.7 g and 99% of the antimony fed to the cell was obtained as metal.