Use of biochar as an alternative material for the treatment of polluted wastewater

Biochar is the product of biomass decomposition, whose physicochemical characteristics are associated with its origin and the combustion method used. Among these properties, the surface area, the formation of macro and micropores, and the presence of functional groups stand out. Due to these characteristics, biochar becomes an alternative material with high adsorption capacity of toxic compounds present in contaminated wastewater. This work provides information on the generation mechanisms of biochar and how they interfere in its physicochemical characteristics. It also describes the parameters involved in the pollutant removal processes and mentions the treatments under which biochar can be subjected to improve its adsorption capacity. Finally, the possible uses or the appropriate final disposal of biochar in order to contribute to the circular economy strategy are indicated.