Reaction Mechanism and Technical Application of Metallic Bismuth Extraction from Bismuthinite Concentrate by Low-Temperature Alkaline Smelting

Release time:2026-04-13

Impact Factor:7.3

DOI number:10.1021/acssuschemeng.3c00081

Journal:ACS SUSTAINABLE CHEMISTRY & ENGINEERING

Key Words:Bismuth metallurgy; Bismuthinite concentrate; Low-temperature alkaline smelting; Thermodynamic simulationreaction mechanism; Copper and molybdenum recycling

Abstract:Traditional bismuthinite concentrate precipitation smeltinghasproblems of low recovery of valuable metals (e.g., Bi, Cu, Mo, andAg), high fuel consumption, and high cost of SO2 flue gastreatment. Therefore, in this study, an eco-friendly alkaline smeltingprocess was proposed to extract metallic bismuth and recover valuablemetals. The phase equilibrium composition of the Bi2S3-Na2CO3-C system was revealed by thermodynamicsimulations at different temperatures and reductant contents. Basedon reaction product characterizations and thermodynamic simulations,the following reaction mechanism and suitable bismuth extraction pathwere confirmed: Bi2S3 first reacted with Na2CO3 to form Bi2O3 and Na2S, and the intermediate (Bi2O3) wasthen reduced to metallic Bi by both C and CO. Under optimized conditions(W (bismuthinite)/W (Na2CO3)/W (coke) = 200:300:20, 900 & DEG;C, 150 min), up to 96.56% Bi, 75.07% Pb, and 85.11% Ag wereenriched in crude bismuth, respectively, while 93.57% Cu, 70.23% Fe,96.63% Mo, and 94.34% W entered the salt slag. More than 99.9% W andMo were recovered as Na2WO4 and Na2MoO4, respectively, from the salt slag by water leaching.In the leaching residue, chalcopyrite, pyrite, and elemental sulfurcould be recovered by flotation. Greenand efficient extraction of metallic bismuth frombismuthite concentrate can be realized based on a reductive sulfur-fixingmechanism.

Indexed by:Journal paper

Discipline:Engineering

First-Level Discipline:Metallurgical Engineering

Document Type:J

Volume:11

Issue:27

Page Number:9932-9946

Translation or Not:no

Date of Publication:2023-06-27

Included Journals:SSCI、SCI、EI