Experiences and Future Challenges of Bioleaching Research in South Korea

Abstract

This article addresses the state of the art of bioleaching research published in South Korean Journals. Our research team reviewed the available articles registered in the Korean Citation Index (KCI, Korean Journal Database) addressing the relevant aspects of bioleaching. We systematically categorized the target metal sources as follows: mine tailings, electronic waste, mineral ores and metal concentrates, spent catalysts, contaminated soil, and other materials. Molecular studies were also addressed in this review. The classification provided in the present manuscript details information about microbial species, parameters of operation (e.g., temperature, particle size, pH, and process length), and target metals to compare recoveries among the bioleaching processes. The findings show an increasing interest in the technology from research institutes and mineral processing-related companies over the last decade. The current research trends demonstrate that investigations are mainly focused on determining the optimum parameters of operations for different techniques and minor applications at the industrial scale, which opens the opportunity for greater technological developments. An overview of bioleaching of each metal substrate and opportunities for future research development are also included.

Bioleaching for Copper Extraction of Marginal Ores from the Brazilian Amazon Region

“…Bacterial adhesion is mediated by the secretion of extra-cellular polymeric substances (EPS) allowing the microorganism to be close to the energy source [7]. Beyond EPS secretion, bacterial cell attachment to ore´s surface showed to be affected by bacterial shape, with a trend of linear chains attachment for rod-shaped bacteria whereas filament-shaped ones tend to appear individually attached [4]. Other biological and physicochemical interactions, such as cell-cell and cell-quartz interactions were demonstrated in model microorganisms, such as E. coli.…”

“…Bioleaching is a well-stablished economical and a more environmentally friendly alternative to the processing of low-grade copper ores (Cu < 0.5%) and mining tailings, responding for 7% of the 2 of 13 world's copper production (17 million tons) [3], however this technology has not been commercially applied in Brazil yet. Bioleaching has also gaining force for metal concentrates, electronic wastes, spent industrial catalysts, contaminated soils and wastewater valuable metals recovery and can improve Brazilian's economical circularization [4].…”

“…Heap bioleaching of crushed secondary sulfide ores (chalcocite and covellite) comprises almost 80% of all industrial scale projects [3]. Despite its high abundance (70% of the world's copper reserves [4]) chalcopyrite is very recalcitrance to bioleaching resulting in slow copper recovery [14] and only few pilot plants have been testing the bioleaching of primary copper ores [10]. Bench-scale column tests are a useful tool to optimize variables such as temperature, pH, Eh, granulometry, aeration rate and bacterial species, among others, that directly affect sulfide ores bioleaching efficiency before the commercial heap implementation [15,16].…”

(Bio)leaching Behavior of Chromite Tailings

“…These results evidence that the chemically exchangeable pool of Cr(VI) is higher in the fresh tailing sample compared with the stockpiled old tailing sample, and in the stockpiled old tailing sample, the pool of Cr(VI) decreases with depth. Stockpiled chromite tailings are susceptible to storing CO 2 within the structures of minerals, a process known as natural carbonation, which is enhanced in mine tailings by a dramatic increase in mineral surface area from crushing during ore processing [84]. During accelerated mineral carbonation, Mg-carbonate mineral and Fe-oxyhydroxide phases sequester transition metals.…”

Effects of Conventional Flotation Frothers on the Population of Mesophilic Microorganisms in Different Cultures

“…Moreover, the problem of global warming and environmental pollution has led the mineral processing industry to focus on the use of low-cost, low-energy, and environmentally friendly methods [4,[6][7][8][9][10]. Thus, several investigations have been focused on the operation and optimization of the bioleaching processes for the extraction of metals from low-grade deposits (by heap bioleaching [11,12]), waste (by columns [13,14]), and concentrates (by bioleaching tanks [13,15,16]) which considerably have lower costs and environment effects [11,[16][17][18][19][20][21][22][23][24].…”