Adsorption of chromium (VI) using cassava peel (Manihot esculenta) as biosorbent: A kinetic study

Abstract

In this research, cassava peel (Manihot esculenta) was used to remove

chromium (VI) from aqueous solution simulating industrial effluents.

Batch adsorption operation was used and tests were performed by varying

the initial concentration of chromium solution (30, 40 and 50 ppm)

and temperature (25, 30 and 35 °C), keeping fixed the adsorbent dosage

(3.33 g/l), the contact time 40 minutos and pH 2, which was adjusted with

sulfuric acid (H2SO4). Data were fitted to four kinetic models: reversible

first-order, pseudo second-order, Elovich and intraparticle diffusion

models. Pseudo second-order model fits best to most experimental data.

Tests were also performed using an initial concentration of 50 ppm and

contact time of 120 minutos, varying the adsorbent dosage (2, 4, 20 and

25 g/l). The higher adsorbent dosage is, the higher percent removal of

Cr(VI) is observed.