LEACHING OF BASE GOLD-BEARING ORE WITH CHLORIDE-HYPOCHLORITE SOLUTIONS

The oxidized and mixed ores are processed by heap leaching. Primary ores with high gold content are floated, but mining of primary ores with low gold content (up to 4 ppm) has recently increased, making traditional floatation methods ineffective. This study aimed to assess the viability of processing gold-bearing ore with combined gravitational and hydrometallurgical methods, utilizing a chloride-hypochlorite leaching solution. The advantage of using chloride-hypochlorite lixiviant lies in the low cost of reagents generated by the electrochemical synthesis of NaCl solution with added HCl. Preliminary tests demonstrated that gold recovery from gravity circuit concentrates processed in the chloride-hypochlorite solution achieved 82% after four hours of leaching, while recovery of gold from copper-gold oxidized ore, following sulfuric acid processing, reached 94%. This research underscores the ecological concerns surrounding cyanide usage in gold processing and explores alternative non-cyanic chemistries for effective gold extraction. The high recovery rates achieved using chloride-hypochlorite solutions suggest they may be a viable alternative to traditional methods.