Utilização de biomassas vegetais na remoção de corantes presentes em soluções aquosas

Abstract

In the present work, biomass of papaya's seeds (Carica papaya L) and Pomegranate peel (Punica granatum) were prepared, characterized and applied as adsorbent in order to remove the cationic dyes, methylene blue (MB) and crystal violet (CV) of aqueous solution. The biomasses in natura were characterized by scanning electron microscopy (SEM), infrared spectroscopy Fourier transform (FTIR), thermal gravimetric analysis (TGA), adsorption and desorption isotherms of nitrogen, ph effects, contact time, dosage of adsorbent and adsorption capacity were studied. A Chemical equilibrium study was obtained by batch process and the experimental data were tuned to models Langmuir, Freundlich, Langmuir-Freundlich (Sips) and Redlich-Peterson models. The isotherm model that suited best was the Langmuir-Freundlich (Sips). The kinetic of adsorption was obtained through the models pseudo-first order, pseudo-second order and Elovich. The pseudo-second order model describes better the adsorption process, indicating Chemisorption. For the AM dye, the maximum adsorption capacity in the pomegranate peel was 68,42 mg g-1 and on the crystal violet was of 54,33 mg g-1 in papaya seed. The results show that the in natura biomass of pomegranate peel and papaya seed can be used as alternative absorbents in removing the dye methylene blue and crystal violet aqueous solution at 25 ° C.