Progress in agricultural waste derived biochar as adsorbents for wastewater treatment

The wastewater generated from diverse human activities needs to be treated, restore, and reused. Researchers have moved from the deployment of synthetic absorbents to manufacturing adsorbents from waste biomass for the elimination of contaminants from wastewater. The deployment of biochar constructed from agricultural waste has elicited significant devotion due to its ready availability, accessibility, low cost, ease of preparation, and environmental sustainability. This review presents developments in the utilization of biochar obtained from agricultural waste for the remediation of domestic wastewater, industrial wastewater, agricultural wastewater, and stormwater. Discussions on the classification, composition, and characteristics of agricultural waste, techniques for biochar production, and characteristics of wastewater as well as the outcomes of the deployment of biochar in the decontamination of wastewater were highlighted. The study concludes that, notwithstanding the identified environmental, social, economic, and infrastructural challenges, biochar constructed from agricultural waste is an effective, efficient, easy to use, and eco-friendly adsorbent for the decontamination of wastewater. Agricultural waste-derived biochar removes contaminants from wastewater and safeguards aquatic ecosystem and contributes to availability of safe water. Future research directions on innovative and more effective avenues for the application of biochar developed from agricultural waste for wastewater treatment are suggested. The outcome of this review will stimulate renewed interests in using readily available and eco-friendly materials in wastewater remediation.