A review of the application of low-cost adsorbents as an alternative method for biosorption of contaminants present in water

Introduction: When using conventional methods to remove contaminants present in water, it generates limitations, such as low efficiency values, and the need for a large operating area added to a high operational cost. As a result, the scientific community has focused its efforts on improving existing removal methods, such as adsorption more focused on the use of biosorbents. These are generally zero-cost waste materials in nature that have a large volume, an example is those generated in agriculture, such as rice husks, peanut husks, cassava husks, and fruit husks, among others. Methodology: This study sought to carry out an extensive review through a broad database, providing biosorbents already produced and used to remove various contaminants. For certain contaminants such as dyes and some heavy metals, dead or live biomasses present promising removal results. The great advantage is that these materials generally present insufficient management, causing several environmental problems. Once used as biosorbents, they solve the problem of bioaccumulation and support the treatment of effluents, making the process sustainable. Results: The most satisfactory results were obtained in the removal of heavy metals, while the use of microbial biomass presented a lower performance, being more dependent on the control of nutrients and other parameters involving the process. The removal of other organic compounds presented greater complexity since they presented functional groups of varying ionic nature, which influence the interaction have the functional groups present on the surface of the biosorbent. Conclusions: Finally, Biosorption presents several advantages such as its cost-benefit, high effectiveness, easy implementation, and how fibrous residues are used, the active sites are freer to adsorb substances and chemicals. Added to this, it enables the use of waste which supports management, reducing environmental pollution resulting from incorrect disposal, making the process sustainable globally.