Advances in Biosorption of Heavy Metals

Biosorption of heavy metals by various types of non-living (microbial) biomass appears as a very cost-effective new alternative for decontamination of metal bearing effluents. The understanding of metal biosorption mechanisms has progressed to the point where the process is being readied for scale up and field applications. Packed bed sorption columns is perhaps the most efficient equipment for this purpose. Process engineering aspects are examined for successful application of newly discovered biosorption materials which serve as natural and very efficient ion exchangers. Easy regeneration of biosorbents increases the process economy making it possible to reuse them in multiple sorption cycles. Optimization of the sorption/desorption cycles results in metal-free effluents and small volumes of highly concentrated metal desorbing solutions facilitating a conventional follow-up metal recovery.