Cinética de adsorção de Cr(VI) de soluções aquosas usando sementes de acerola

This study aimed to evaluate the use of the acerola seeds (Malpighia emarginata L.) in the removal of Cr(VI) from aqueous solutions. The adsorbent was obtained by heat treatment at 170 °C, crushed and classified by particle size. The determination of Cr(VI) was carried out by UV-visible through the complexation with 1,5-diphenylcarbazide, measuring the absorbance at 540 nm wavelength. The experiments were performed at 25 ± 1 °C, varying contact time 10-140 minutes, pH 2-8 and adsorbent mass 0.1-0.6 grams. The average removal of Cr(VI) was 66% using 0.1 g of biosorbent, pH 2.0 and contact time 120 min. Uptake kinetics follows the pseudo-second-order model.