Desenvolvimento de biossorventes para remoção de crómio de efluentes industriais

The removal of Cr (III) and Cr (VI) from water solutions by biosorption on an Arthrobacter viscosus biofilm supported on a granular activated carbon was studied and is presented. The following parameters were considered: concentration of hexavalent Cr, concentration of trivalent Cr, competition with other metal, Cd, and cellular viability. The biofilm was kept active in different growth media and afterwards suffered a thermic treatment for reduction of metabolism and reutilization as biossorbent. High values of Cr (VI) uptake were reached, with a maximum at 80 ppm in the original solution. Cr (III) removal was less efficient but operational conditions were not yet optimised. The presence of another ion interfered with the overall Cr removal and the uptake was slightly reduced. There seems to be some advantage in the maintenance of the metabolic activity in terms of the metallic solution remediation.