GROUNDNUT HUSK (ARACHIS HYPOGAEA) AS AN ADSORBENT: EVALUATION OF ADSORPTIVE CHARACTERISTICS FOR CR (VI) FROM AQUEOUS SOLUTION

Abstract

Abstract— In the present study, the removal of chromium (VI) from aqueous solutions using groundnut husk (Arachis hypogaea) was investigated. Effect of experimental parameters namely adsorbent dose, pH, reaction time, temperature and initial metal concentration studied in a batch system which reveals that Cr(VI) adsorption increases with increasing dose and reached maximum at 9 g/L at optimum pH 6. The adsorption kinetics studied by fitting the data into pseudo-first and pseudo-second-order kinetic models and pseudo-second-order model fitted well with a high correlation coefficient. Isotherm data analyzed by Langmuir and Freundlich adsorption isotherm; Langmuir isotherm gave a better fit to the experimental data. Results indicate that groundnut husk can provide an efficient and cost-effective technology for eradicating chromium from aqueous solution. Index Term — Groundnut husk; Adsorption kinetics; Langmuir and Freundlich isotherm; chromium