Glycine–Thiosulfate Leaching: A Mercury and Cyanide-Free Approach to Gold Extraction
A Review and Sustainable Alternative to Sodium-Based and Cyanide-Containing Gold Leaching Agents - Glycine – Thiosulfate Hybrid System.
Author: Bruce A. Cosgrove, BSc, MSc | Published peer reviewed - Sustainable Technology eJournal | November 2025 |DOI:10.2139/ssrn.5801183.
Introduction
This study examines conventional sodium-based and cyanide-containing leaching systems used in artisanal mining, including urea, sodium sulfate, sodium chloride, sodium carbonate, and thiosulfate formulations. These methods remain widely adopted despite their environmental and toxicological risks.
This research advances sustainable hydrometallurgy through the development of a glycine–thiosulfate hybrid leaching system, providing a non-toxic, cyanide- and mercury-free alternative for gold extraction.
👉 Hybrid ligand systems demonstrate how alternative lixiviants can reduce dependence on both mercury and cyanide while maintaining efficient gold recovery under appropriate processing conditions →
Under optimized laboratory conditions, glycine–thiosulfate systems achieve 70–90% gold recovery, with performance dependent on ore type, particularly oxide and mildly refractory ores.
👉 Full references and supporting research are provided in the complete article accessed here: A Review and Sustainable Alternative to Sodium-Based and Cyanide-Containing Gold Leaching Agents - Glycine – Thiosulfate Hybrid System →
### Scientific Context
This article is grounded in applied botanical systems research and connects to the following peer-reviewed and technical publications:
👉 Glycine–Thiosulfate Hybrid System →
👉 Botanical Alternatives: Toward Safer, Evidence-Based Gold Recovery→