EVALUATION OF THE ADSORPTIVE CAPACITY OF ACTIVATED CARBON PRODUCED WITH BARK OF PARÁ NUT

Abstract

The present work proposes the use of bark nut of Pará, a residue generated from the beneficiation of Brazil nut (Bertholletia excelsa H.B.K) for the production of activated carbon aiming its application in the adsorption of the textile dye of methylene blue, as an alternative method of effluent treatment. The activated carbon of bark Pará nut was obtained with different ZnCl₂ impregnation ratios and temperatures from 400-600 ^oC. The best activated carbon was produced with an impregnation ratio of 2.0 and a carbonization temperature of 600 °C, where 90% of the dye concentration was removed. The values of the correlation coefficients (R²) indicated that the adsorption kinetic model of pseudo-second order presented the best fitting to the experimental data. The results of the adsorption isotherms were fitted to the Langmuir and Freundlich models, and the Langmuir presented the best fitting to the data. The comparative result between the activated carbon of bark Pará nut and the commercial activated carbon indicated dye removals of 94% and 92%, respectively. The results showed the bark nut of Pará may constitute a sustainable alternative of low cost in the efficient removal of dyes from textile effluents.