Fenton oxidation of cork cooking wastewater--overall kinetic analysis.
In the present work, the possibility of using chemical oxidation through Fenton's reagent for the pre-treatment of cork cooking wastewaters was exploited. Aiming both the selection of the best operating conditions (pH, Fe2+:H2O2 ratio and initial H2O2 concentration) and the evaluation of the overall reaction kinetics, trials were performed in a batch reactor. Operating at pH = 3.2, H2O2 concentration = 10.6 g/L and Fe2+:H2O2 ratio = 1:5 (by weight), about 66.4% of total organic carbon (TOC), 87.3% of chemical oxygen demand (COD) and 70.2% of biochemical oxygen demand (BOD5) were removed and an increase of the BOD5/COD ratio from 0.27 to 0.63 was achieved. In the temperature range 20-50 degrees C, the best performance was obtained at 30 degrees C. The kinetic study was undertaken at different initial TOC concentrations and temperatures. Overall kinetics can be described by a second-order followed by a zero-order rate equation and the apparent kinetic constants at 30 degrees C are k = 2.3 x 10(-4) L/mg min and k0 = 26.0 mg/L min, respectively. The experiments performed at different temperatures confirmed the global kinetic model and allowed to calculate the global activation energy for the second-order reaction (70.7 kJ/mol).
Guedes
Anabela M
AM
Departamento de Engenharia Química, Faculdade de Engenharia-Universidade do Porto, Rua Dr. Roberto Frias s/n, 4200-465 Porto, Portugal.
Madeira
Luis M
LM
Boaventura
Rui A
RA
Costa
Carlos A
CA
D006358:Hot Temperature; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007220:Industrial Waste; D007501:Iron / Q000737:chemistry*; D007700:Kinetics; D016877:Oxidants / Q000737:chemistry*; D010084:Oxidation-Reduction; D032102:Phellodendron; D014865:Waste Disposal, Fluid / Q000379:methods*; D018508:Water Purification / Q000379:methods*
C045076:Fenton's reagent; D007220:Industrial Waste; D016877:Oxidants; D006861:Hydrogen Peroxide; D007501:Iron