Interaction of Metal Ions with Mono- and Polysaccharides for Wastewater Treatment: A Review

Chemical contamination of water from a wide range of toxic compounds, especially heavy metals, is a critical environmental problem due to their potential human toxicity. Therefore, development of technologies that allow the removal of toxic pollutants from wastewater is a need. Among all the common heavy metals treatment processes, biosorption is one of the more popular and efficient processes. The important number of publications concerning adsorption and remediation of metal ions from aqueous solution by natural and modified polysaccharides shows an increasing interest in biopolymer uses for environment preservation. The present review describes recent developments on biosorption processes using agricultural by-products, mainly mono- and polysaccharides extracted from natural resources. General considerations on metal ions complexation mechanism and interactions between metals and saccharides are first described. Then, a review on metal ions biosorption processes and recent development of new polysaccharide-based materials is carried out and shows their high adsorption capacities and their attractive character. Finally, advantages and possible limitations of using such biosorbents for metal ions adsorption process are discussed.