Adsorption potential of pristine biochar synthesized from rice husk waste for the removal of Eriochrome black azo dye

Abstract

Water contamination is a severe problem in today‘s world and it is progressively increasing day by day due to exponential industrial growth. The main contaminants found in water are dyes, heavy metals, pesticides, PFAS, etc. which are difficult to segregate with normal filtration units. In recent times, there has been a lot of focus on the removal of contaminants by ion exchange, filtration, distillation, adsorption, etc. Biochar derived from feedstock has been an excellent adsorbent and is therefore used in many applications like the removal of various heavy metals, azo dyes, inorganic and organic pollutants, etc. Azo dyes, which are mostly used in leather and textile industries are carcinogenic in nature, making them a great threat to mankind. In this article, we have synthesized pristine biochar at 600 °C through pyrolysis and explored its potential in the removal of anionic azo dye (Eriochrome black T). The biochar showed good porosity, as confirmed by FESEM images. The synthesized biochar showed excellent adsorption capacity for the 94 % removal of Eriochrome black T dye at 2.0 pH, 1.5 g catalyst dosage, 2 hr time, and 20 ppm initial dye concentrations. This work showed effective removal efficiency of pristine biochar in the removal of dyes from the contaminated water in the near future.