Recovery of Valuable Heavy Metals from Polluted Soil Using Phytomining Process - A New Challenge for Earning Secondary Raw Materials and Health Risk Reduction

Abstract

Phytomining is an innovative application of phytoremediation process that involves accumulators or hyperaccumulator plants grown in polluted soils, being able to accumulate high concentration of metals in their tissues, where from valuable heavy metals (e.g. nickel, cobalt, copper, zinc) will be recovered by biomass processing. This technology can be successfully applied to treat contaminated soils with low to moderate metal concentrations and fast-growing plants are usually required to ensure high biomass and efficient metal uptake. Phytomining involves lower costs compared to conventional methods such as mining, and contributes both to the remediation of contaminated soils and provides additional beneficial resources that can be used as raw material in other processes from industry. After harvesting the plants, heavy metals are extracted either by biomass incineration, microbial fermentation, extraction or by chemical treatments. The main objective of this paper is to describe and highlight the importance of phytomining process in cleaning-up the polluted media by phytoextraction and recovery of valuable heavy metals from biomass of the selected plants.