Bioadsorbents for remediation of heavy metals: Current status and their future prospects

TLDR

Biosorption uses dead cellulosic or microbial biomass to bind metal ions from water, offering a cost‑effective, greener alternative to conventional methods, yet large‑scale industrial application remains limited. This review aims to analyze the biosorption technology, covering the biosorbents used and the factors influencing the process. The review examines biosorbent types, influencing factors, and regeneration/desorption strategies. The review highlights that improving biosorbent properties and enabling repeated reuse enhance economic value, while multiple inhibitory mechanisms hinder commercial deployment. Keywords: algae, bacteria, biosorption, fungi, plant organic waste, toxic metal.

Abstract

The biosorption process has been established as characteristics of dead biomasses of both cellulosic and microbial origin to bind metal ion pollutants from aqueous suspension. The high effectiveness of this process even at low metal concentration, similarity to ion exchange treatment process, but cheaper and greener alternative to conventional techniques have resulted in a mature biosorption technology. Yet its adoption to large scale industrial wastewaters treatment has still been a distant reality. The purpose of this review is to make in-depth analyses of the various aspects of the biosorption technology, staring from the various biosorbents used till date and the various factors affecting the process. The design of better biosorbents for improving their physico-chemical features as well as enhancing their biosorption characteristics has been discussed. Better economic value of the biosorption technology is related to the repeated reuse of the biosorbent with minimum loss of efficiency. In this context desorption of the metal pollutants as well as regeneration of the biosorbent has been discussed in detail. Various inhibitions including the multi mechanistic role of the biosorption technology has been identified which have played a contributory role to its non-commercialization. Keywords: Algae, Bacteria, Biosorption, Fungi, Plant organic waste, Toxic metal