REMOVAL OF AN ORGANIC DYE FROM TURMERIC (CURCUMA LONGA) USING ACTIVATED CARBON PREPARED FROM GROUNDNUT (ARACHIS HYPOGEA) HUSK

Abstract

Carbon-based adsorbents were prepared from groundnut husk by impregnation with H3PO4 and NaOH before or after carbonization. The adsorbents were characterised by Brunauer-Emmett-Teller (BET) adsorption/desorption isotherms, scanning electron microscopy (SEM), thermogravimetric/differential thermal analysis (TGA/DTA), and Fourier-Transform infrared spectroscopy (FTIR). These adsorbents were used for the removal of a turmeric based organic dye from aqueous solution. The results obtained from measuring the pH, temperature, and particle size effects on the adsorption process showed that the adsorbent impregnated with H3PO4 before carbonization (CA-B), achieved a higher percentage removal of turmeric dye at all parameters studied. The pseudo-second-order kinetic model explained the experimental data, the adsorption was controlled by liquid ?lm and intraparticle diffusion models simultaneously, the equilibrium data was a good ?t to the Langmuir adsorption isotherm model, and physisorption was the predominant sorption process. The results from this research have shown that adsorbents with suitable characteristics for the removal of turmeric dye from aqueous solution could be produced from groundnut husk.