The Characteristic Dissolution of Valuable Metals from Mine-Waste Rock by Heap Bioleaching, and the Recovery of Metallic Copper Powder with Fe Removal and Electrowinning

Abstract

: In order to recover the metallic copper powder from the mine-waste rock, heap bioleaching, Fe removal and electrowinning experiments were carried out. The results of heap leaching with the mine-waste rock sample containing 0.034% Cu showed that, the leaching rate of Cu were 61% and 62% in the bacteria leaching and sulfuric acid leaching solution, respectively. Sodium hydroxide (NaOH), hydrogen peroxide (H 2 O 2 ) and calcium hydroxide (Ca(OH) 2 ) were applied to effectively remov Fe from the heap leaching solution, and then H 2 O 2 was selected for the most effective removing Fe agent. In order to prepare the electrolytic solution, H 2 O 2 were again treated in the heap leaching, and Fe removal rates were 99% and 60%, whereas Cu removal rates were 5% and 7% in the bacteria and *Corresponding author: +82-62-230-7878, E-mail: cybpark@chosun.ac.kr 김봉주⋅조강희⋅최낙철⋅박천영 -208 -sulfuric acid leaching solutions, respectively. After electrowinning was examined in these leaching solution, the recovery rates of Cu were obtained 98% in bacteria and obtained 76% in the sulfuric leaching solution. The dendritic form of metallic copper powder was recovered in both leaching solutions.

Experiences and Future Challenges of Bioleaching Research in South Korea

“…Lee et al [50] revealed that the removal speed of an integrated process of biological leaching and electrokinetics was around 2.5 times faster than that obtained in independent processes. Similarly, Park et al [51] obtained Cu recoveries of approximately 98% after applying electrowinning to the PLA obtained by biological means which is significantly higher than the 78% obtained by acid leaching.…”