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Bioremediation for Sustainable Environmental Cleanup

4.9 Conclusions and Prospects

With reference to the presented analysis of biosorption and bioaccumulation potentials, the following

conclusions can be formulated:

Heavy metals are among the pollutants that are the most difficult to eliminate as a complement to

currently employed physical and chemical approaches. When using biotechnological methods to

remove heavy metals from the environment, several physicochemical factors should be considered,

including temperature, pH, biomass contact time with a solution containing metals, biomass

concentration and age and toxicity when using living organisms. Physical and chemical changes,

as well as biomass immobilization, can be used to improve metal removal efficiency. Stirred tank

reactors, fixed-bed reactors, and fluidized-bed reactors are the most often used reactors. One of the

most appealing aspects of using biosorbents is that they can be regenerated.

The removal of heavy metals from the environment is critical for preserving a healthy and safe

ecosystem. While physicochemical methods are frequently employed for comparable reasons,

biological processes, namely biosorption/bioaccumulation, appear to be a potential alternative option

in terms of prices, technological requirements, metal recovery efficiency, energy requirements and

environmental consequences. When biosorption and bioaccumulation were compared, the former

was revealed to be superior owing to the usage of dead/inactive biomaterials, which limit metal

uptake via the cell wall. Due to the variety of the microbial cell surface, selective adsorption remains

difficulty. Furthermore, when using live cells for heavy metal removal, genetic engineering may

be required to improve microbial strains’ metal tolerances. More research is needed to get a better

understanding of heavy metal removal by these two methods.

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