"Environment" research area

Selective Biomining Using Bacteria

Primary Investigator - Jeffrey GralnickPrimary InvestigatorJeffrey Gralnick
Co-Investigators: NA
Industry PartnersNorth Star Manganese Inc.
Award Type: Seed Grant - Postdoctoral Research Scholar

Problem: Due to increasing demands for manganese alloys and rare metals, there is a need to concentrate and recover minerals from low-grade ores, waste rock, and tailings. Many deposits in Minnesota contain mixtures of manganese and iron that represent valuable resources if their constituent metals can be separated. However, hydrometallurgical and pyrometallurgical processes with high energy inputs are unprofitable with these ores, and most microbial bioleaching approaches rely on sulfur release that is undesirable in Minnesota. New, green technologies are needed to passively extract specific metals and separate them for easy downstream purification without sulfate or acid production.

Solution: This proposal describes a new approach where bacteria self-control redox potential without external input, to reductively solubilize specific metals while avoiding production of environmentally harmful products.

Impact: Manganese ore found in Minnesota is commonly contaminated with iron and other metals that have significant economic value. We hypothesize that organisms with built-in redox control can separate these metals.