Kinetic study and hydrogen peroxide consumption of phenolic compounds oxidation by Fenton’s reagent

Abstract

Synthetic solutions of phenol, o-, m-and p-cresol were oxidised by using Fenton's reagent. The application of substoichiometric dosage of H 2 O 2 led to the formation of intermediate compounds, continuing later the oxidation to complete oxidation. An important objective was to analyze the effect of hydrogen peroxide dosage applied and the reaction pH together with the iron oxidation state on the degradation level. A kinetic model was derived from a reaction mechanism postulated which was used to analyze the results of the experiments. Another aim was to analyze the hydrogen peroxide consumption. Noteworthy results include an increase in oxidant consumption to intensify phenol removal. Furthermore, oxidant consumption was analyzed through the ratio H 2 O 2 to phenol removed and the average specific rate of removal (ASRR). By analyzing these two parameters it has been possible to ascertain the most favorable strategy for an efficient application of H 2 O 2 .

Comparing Fenton Oxidation with Conventional Coagulation Process for RR198 Dye Removal from Aqueous Solutions

“…As the concentration increased to 10 mm, the efficiency reduced dramatically. As stated in other studies, the decrease of efficiency can be attributed to the excessive concentration of hydrogen peroxide and spontaneous decomposition of this oxidizing agent (18,19). With the increase of iron sulfate from 10 to 15 mM, favorite decolonization was observed, because any increase in the level of iron concentration resulted in the production of more hydroxyl radical, and consequently the speed and rate of bleaching increased.…”

Modeling of the radicalary state in the H2O2/UV oxidation system to predict the degradation kinetics of phenolic mixture solutions

“…These constants adequately describe the elimination kinetics of both reagents and result from the sum of the kinetic terms of the different radicals, as can be seen in Eqs. (17) and (18).…”

Degradation of Para-Phenylenediamine in Aqueous Solution by Photo-Fenton Oxidation Processes

“…When pH >3, oxidation efficiency rapidly decreases due to auto-decomposition of H2O2 affecting the production of OH • radicals (Badawy and Ali, 2006) and deactivation of ferrous catalyst with the formation of ferric hydroxide precipitates (Luis et al, 2009 …”