APPLICATION OF ETHALINE DEEP EUTECTIC SOLVENT FOR DISSOLUTION OF GOLD IN SULFIDIC REFRACTORY ORE UNDER VARYING PH

Abstract

Conventional extraction methods like cyanidation face significant challenges with refractory ores, prompting the need for more sustainable alternatives to gold extraction and its metal production. This study evaluates the application of Ethaline, a deep eutectic solvent (DES) composed of choline chloride and ethylene glycol, for dissolving gold from sulfidic refractory ores under varying pH conditions. Ethaline DES, characterized by its non-toxic and biodegradable properties, emerges as a promising solution. Experiments were conducted at three pH levels: 4 (acidic), 7 (neutral), and 10 (basic). Ore samples were treated with Ethaline DES mixed with iodine as an oxidant, and gold dissolution was monitored over a 72-hour period. The results revealed that the neutral pH condition achieved the highest gold dissolution rate, peaking at 56.7% at 48 hours, followed by the basic and acidic conditions. These findings underscore the critical role of pH in optimizing the dissolution process and highlight the potential of Ethaline DES as a green solvent for gold extraction, promoting more sustainable mining practices and reducing environmental impact.