Author(s)
Sabrina S.T.F, Venujah P., Arasaretnam S.
Abstract
Water pollution and dyes are closely linked, particularly due to industrial activities. Dyes are significant pollutants, often released into water bodies through industrial effluents from textile industries, pulp mills, and dye manufacturing plants. These colored wastewater discharges contain various chemical compounds that can be harmful to aquatic ecosystems and human health. This study deals with the adsorption of Solochrome Black T on rice husk (RH) biochar. The removal of Solochrome Black T dye from aqueous solutions is significant due to its environmental and health impacts. Using pyrolyzed and raw biochar as adsorbents is important because it offers a cost-effective and sustainable solution for removing such contaminants. Biochar has a high surface area and porosity, which make it effective for adsorbing organic pollutants like dyes from water, thereby mitigating environmental contamination and promoting water safety. Characterization of the prepared materials has been conducted by the Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). From the analyses, it is revealed that the operational parameters of initial concentration, adsorbent dosage, contact duration, and temperature were analyzed, with one factor changeable at a time and the others constant. A peak at 3276 cm-1 has been observed in raw RH, indicating the presence of free water molecules, which disappear in biochar following the pyrolysis process. This suggests that higher dehydration and aromatization occurred during the pyrolysis process. The XRD pattern identifies a widening peak of silica peak diffraction at 2q = 22°. It is shown that the prepared material is more porous with higher surface area compared with its parent material. The adsorption process mechanism was found as physio-sorption mode dominating over chemisorption mode of removal of dye, following pseudo-second order model and spontaneous nature (indicated from – ∆Gº). Maximum adsorption capacity of RH to remove Solochrome dye in optimized conditions is 46.948 mg g-1. Separation factor ‘RL’ point outs the feasibility of this process, which is further confirmed by the linearity of equilibrium adsorption isothermal data correlation coefficient values.