ABSTRACT

Chars obtained from the co-pyrolysis of rice husk (50% w/w) and polyethylene (50% w/w) were converted to activated carbons by physical activation. A fraction of the resulting activated carbon (PCPA) was submitted to chemical treatment with HNO3 for functionalization purposes (PCAPCT). Both activated carbons were used in Cr(III) removal assays from liquid-phase. A commercial activated carbon, either submitted or not submitted to HNO3 treatment (CACCT and CAC, respectively) was used for comparison purposes. During Cr(III) removal assays, two different solid/liquid ratios (S/L) were tested: 5.0 and 10.0 g L−1. Concerning Cr(III) removal, PCPA was more efficient than CAC; with a S/L ratio of 10.0 g L−1, PCPA was able to remove 99.9% of Cr(III) by precipitation. On the other hand, PCPACT performed slightly better with a S/L ratio of 5 g L−1 than CACCT, with 50.9% Cr(III) removed only by adsorption mechanism.