Evidences of EPS-iron (III) Ions Interactions on Bioleaching Process Mini-review: The Key to Improve Performance

Abstract

Chemolithotrophic microorganisms have been used on commercial extractive bioprocess of valuable metals as cooper, nickel, zinc and gold, from their ore sulfides or concentrates. Bioleaching is a metal solubilization process that involves the production of oxidizing chemicals as iron(III) ions and sulfuric acid from biomining microbes that promotes an attack of mineral matrix releasing the metal ions of interest. In this mini-review, the interfacial interaction between bacterial cells and mineral surface is promoted by biofilm formation and has been described as fundamental to biological ore dissolution. Complexes formed between iron(III) ions and functional groups from microbial extracellular polymeric substances(EPS) have been recently described by mediating the oxidative attack to sulfide minerals promoting metal solubilization. An approach from bacterial adhesion and their interfacial dynamics by EPS complexed iron(III) ions beside sulfide minerals are described. DOI: http://dx.doi.org/10.17807/orbital.v11i3.1389

Keywords

• bacterial adhesion
• biofilms
• bioleaching
• extracellular polymeric substances