Adsorption of water pollutants using H 3 PO 4 -activated lignocellulosic agricultural waste: a mini review

Lignocellulosic wastes are potential low-cost feedstock for the production of high surface area activated carbon. Activation using phosphoric acid encourages the splitting of biomass macromolecules and crosslinking reactions in creating porous textures. The resultant activated carbons endow surface area of 190-2000 m2/g and adsorption capacities for various pollutants of 16.1–535 mg/g. The process renders high carbon yield, low energy cost, exceptional removal performance and less environmental impacts. The lignocellulosic carbon activated with H3PO4 has properties similar to carbon oxides; its acidic groups are tightly bound to the carbon lattice, and it is chemically and thermally stable. This article is aimed to provide an overview of the recent outcomes in phosphoric acid activation of lignocellulose agricultural wastes and offer the way forward toward sustainable environment.