Metodologia de superfície de resposta aplicada para determinar as condições ótimas (quase-ótimas) do processo fenton no tratamento de águas residuárias de curtume

Abstract

A response surface methodology (RSM) was applied to determine the optimal conditions (near-optimal) in a batch reactor Fenton (BRF) used to treated wastewater from tannery (WT). The parameters investigated were the RSM (q 1 ) iron concentration (0 – 20 mg L -1 ); (q 2 ) hydrogen peroxide (50 – 100 mg L -1 ) and (q 3 ) pH of the solution (3 – 7). The level significance (p<0.5 %) of the coefficients q 1, q 2 and q 3 was evaluated by experimental design, the removal of COD, color, turbidity and sludge were measured. The desirability function BRF determined for the optimal experimental conditions (near- optimal) for q 1 = 5 mg L -1 ; q 2 = 75 mg L -1 and q 3 = 4. A kinetic study was carried out (0 - 300 min) being determined the concentrations total dissolved carbon (TDC), dissolved inorganic carbon (DIC) dissolved organic carbon (DOC), and total dissolved nitrogen (TDN) and elements concentration of Cl, Fe, Cr and Zn. In stirring time 60 min was observed the best results from removal of COD, turbidity, sludge mass, Cl and TDC 65, 91, 30, 40 and 80%, respectively. With the development of this research it found that the BRF can be considered an effective alternative in the treatment of tannery wastewater.