Advanced oxidation of cork‐processing wastewater using Fenton's reagent: kinetics and stoichiometry

Abstract

Abstract This work evaluates Fenton oxidation for the removal of organic matter (COD) from cork‐processing wastewater. The experimental variables studied were the dosages of iron salts and hydrogen peroxide. The COD removal ranged from 17% to 79%, depending on the reagent dose, and the stoichiometric reaction coefficient varied from 0.08 to 0.43 g COD (g H 2 O 2 ) −1 (which implies an efficiency in the use of hydrogen peroxide varying from 17% to 92%). In a study of the process kinetics, based on the initial rates method, the COD elimination rate was maximum when the molar ratio [H 2 O 2 ] o :[Fe 2+ ] o was equal to 10. Under these experimental conditions, the initial oxidation rate was 50.5 mg COD dm −3 s −1 with a rate of consumption of hydrogen peroxide of 140 mg H 2 O 2 dm −3 s −1 , implying an efficiency in the use of the hydrogen peroxide at the initial time of 77%. The total amount of organic matter removed by Fenton oxidation was increased by spreading the H 2 O 2 and ferrous salt reagent over several fractions by 15% for two‐fractions and by 21% for three‐fractions. Copyright © 2004 Society of Chemical Industry