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 | Independent Scientific Researcher | Posted - Sustainable Technology eJournal | November 2025

Structured Research Record

DOI:10.2139/ssrn.5801183 →

Structured Record:Wikidata →

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.

👉 Continue Reading: A Review and Sustainable Alternative to Sodium-Based and Cyanide-Containing Gold Leaching Agents - Glycine – Thiosulfate Hybrid System →

Research Context

This article contributes to Bruce A. Cosgrove's broader research into mercury-free gold recovery, alternative extraction chemistry, and environmentally compatible mineral-processing systems →

The research examines plant-derived lixiviants, alternative complexation chemistry, solution behavior, mercury-reduction strategies, and lower-toxicity approaches to gold extraction and artisanal and small-scale mining.

🌿 Explore Mercury-Free Botanical Gold Recovery →

Explore the research, publications, and applied chemistry behind botanical and alternative approaches to mercury- and cyanide-dependent gold-processing systems.

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