SBIR Phase II: A Novel Integrated Bioleaching Process for Chalcopyrite: An Alternative to Smelting

Little Bear Laboratories Inc, Golden CO

Investigators

Abstract

This Small Business Innovation Research Phase II project is developing a novel electrobiochemical leaching (EBL) approach to recover copper from chalcopyrite, providing an alternative to smelting. Chalcopyrite is the most common copper ore, yet it is difficult to process hydrometallurgically because it passivates due to formation of refractory surface layers. The EBL approach in Phase 1 was shown to prevent this passivation and to result in faster and more complete copper extraction than conventional bioleaching approaches. The Phase II research objectives are to: 1) demonstrate the versatility of the process by determining the extent of copper extraction from different sources of chalcopyrite ore; 2) determine the optimum bioreactor configurations for the EBL approach; and 3) make a large laboratory scale (50 to 100 kg) demonstration of the process for determining preliminary process economics. The research will measure the extent of copper extraction and extraction kinetics by EBL, including the determination of metallurgical balances. The results of the Phase II research will provide the data required to establish preliminary economic feasibility of the process and to convince investors or operators (mining company) to support a pilot scale demonstration. If successful, the EBL approach will provide a new technology in mineral extractions that will open additional reserves of copper in the US and elsewhere and reduce smelting of copper.