Priming Chromobacterium violaceum as a Gold Bioleacher in E-wastes: Advantages and Challenges

Abstract

With rapid technological advancement, the life span of electronic devices has become increasingly short, contributing to massive electronic waste (E-waste) and demanding sustainable management. E-waste contains precious metals like gold (Au) many fold higher than natural mining ores. However, the current techniques of recycling are not efficient. Methods like pyrometallurgy and hydrometallurgy not only require higher energy expenditure but also lead to environmental pollution, hence necessitating an alternative greener technology. In line with that, metal leaching using microorganisms is gaining popularity, and Chromobacterium violaceum has been considered a promising candidate. However, the heterogeneity of culture technique and abiotic condition variations have been a perceived challenge in priming C. violaceum as an Au bioleacher for upscaled industrial applications. Thus, the current review discusses what makes C. violaceum an excellent candidate for Au bioleaching and how to overcome the challenges associated with the application. This review will significantly enhance the current understanding of C. violaceum as an Au bioleaching agent, hence addressing the existing knowledge gaps.

Keywords

• Bioleaching
• Biohydrometallurgy
• Chromobacterium violaceum
• Cyanagenic bacteria
• E-waste