Arachis hypogaea shell - An approach towards waste utilization for cationic and anionic dye removal

In this work, the treatment of an anionic dye (Bromophenol Blue (BB)) and a cationic dye (Methyl Green (MG)) using activated biomass waste as an adsorbent was explored. Using Peanut shells as a precursor, chemically activated carbon was synthesized. The activation was carried out using different activation ratios of Arachis hypogaea: KOH (1:4, 1:5, and 1:6). The synthesized Arachis hypogaea Shell Activated Carbon (ASAC) was analyzed for its surface morphology using SEM, the porous characteristics using BET analysis, and chemical composition using FT-IR analysis. Further, the effect of various parameters like pH (3-11), adsorbent dosage (1-5 g/l), and contact time on color and COD removal of BB and MG aqueous solutions were studied. At optimum condition 500 mg/g and 555.55 mg/g maximum adsorption capacity for BB and MG respectively was obtained. The adsorption kinetics and different isotherm models were used to analyze the experimental data.The isotherm model that fitted well with the experimental data for both the dyes was Langmuir and adsorption followed pseudo-second-order kinetics.

Automated summary

This study explored the treatment of anionic dye (BB) and cationic dye (MG) using activated biomass waste as an adsorbent. The results showed that the Arachis hypogaea shell activated carbon had a maximum adsorption capacity of 500 mg/g for BB and 555.55 mg/g for MG under optimal conditions. The experimental data was well fitted by the Langmuir isotherm model and pseudo-second-order kinetics model.