In-situ electrochemical reconstruction of tungsten carbide using Na2CO3-containing molten salt. Issue 13 (1st July 2022)

• Record Type: Journal Article
• Authors: Zhang, Qinghua; Xi, Xiaoli; Zhang, Liwen; Nie, Zuoren
• Is Part Of: Ceramics international. Volume 48:Issue 13(2022)
• Page Start: 19444
• Page End: 19451
• Publication Date: 2022-07-01
• Subjects: Tungsten carbide -- Consumable anode -- Molten salt electrolysis -- Sodium carbonate; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2022.03.243
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: This paper reports a novel method for rapid atomic-level reconstruction of tungsten carbide (WC) using Na2 CO3 -containing molten salt. Herein, WC was used as consumable anode and Na2 CO3 was active species on WC anode and carbon donor. Thermodynamic calculations were used to verify the feasibility of this electrolytic method for reconstructing WC. Experimental results showed that the addition of Na2 CO3 significantly enhanced dissolution efficiency of WC. Therefore, more tungsten (W) source was supplied. Electrochemical analysis demonstrated that Na2 CO3 also supplied carbon by two-step reduction process, which led to the formation of WC. These experiments confirmed that cathode product was converted from W to WC by the introduction of Na2 CO3 additive into molten salt. WC phase started to form at cell voltages above 2.2 V. In initial stage of reaction, carbonate was preferentially reduced in cathode region to form amorphous C. As the reaction proceeded, W ions migrated from anode and began to participate in reduction process, forming W. Finally, W was transformed to WC by carbonization process.