Removal of chromium (VI) in aqueous solution by oat biomass (Avena sativa)

Abstract

Chromium (VI) removal capacity in aqueous solution by oat biomass was analyzed by the diphenylcarbazide method. Bioadsorption was evaluated at different pH values (1, 2, 3 and 4) and at different times. The effect of temperature in the range of 28 °C to 60 °C and the removal at different initial Cr (VI) concentrations of 200 to 1000 mg/L were also studied. The highest bioadsorption (100% with 100 mg/L of the metal and 1 g of biomass) was at 8 h, at pH of 1.0 and 28 °C. With regard to temperature, the highest removal was to 60 °C, with a 100% removal at 90 min. Removal was more efficient when higher concentrations of biomass were used (100%, 3 h and 5 g of biomass). Untreated biomass (washed and ground biomass) showed excellent metal removal capacity in situ, 82.6% and 85.3% removal in contaminated soil and water, respectively, after 10 days of incubation, using 25 g of the biomass (100 mL of water). These results show that Cr (VI) can be removed from industrial wastewater using oat biomass.