Sequestration of heavy metals from soil with Fe–Mn concretions and nodules

Abstract

In recent years, heavy metal contamination has become a major environmental issue in many parts of the world. Fe and Mn oxides, oxyhydroxides and hydroxides have long been recognized as scavengers playing an important role in controlling the location, mobility and bioavailability of metal contaminants in soils. Fe–Mn concretions and nodules are discrete bodies made of soil or sediment materials cemented together under the influence of Fe and Mn oxides. Here metals sorption by Fe–Mn concretions and nodules are surveyed and critical reviewed. Valuable available literature data demonstrate that the formation of Fe–Mn concretions and nodules is the most efficient and durable process for metal contaminants sequestration in the soils. The papers discussed in this review show that the application of Fe–Mn concretions and nodules, as geochemical scavengers for remediating metal contaminated soils, is strongly recommended.