Use of EAF dust as heterogeneous catalyst in Fenton oxidation of PCP contaminated wastewaters

Abstract

In this study, chemical oxidation tests using H 2O 2 were performed on a solution contaminated with 100 mg l −1 of pentachlorophenol (PCP). The effectiveness of electric arc furnace dust and hematite as heterogeneous catalysts was evaluated. Reactions were conducted at pH 2 for 24 h. Either H 2O 2 stabilized with KH 2PO 4 or un-stabilized H 2O 2 was used. Total organic carbon (T.O.C.) removal and chloride release from PCP molecule were monitored. Results showed that the maximum removal yields for electric arc furnace (EAF) dust (49.2% T.O.C., 56.7% Cl) were achieved when H 2O 2:PCP ratio was 10:1 and Fe:H 2O 2 = 1:5 for unstabilized H 2O 2 and when H 2O 2:PCP = 10:1 and Fe:H 2O 2 = 1:1 for stabilized H 2O 2 (48% T.O.C., 60.6% Cl). The maximum yield using hematite (45.2% T.O.C., 55.2% Cl) was obtained when H 2O 2:PCP ratio was 10:1 and Fe:H 2O 2 was 1:2. When EAF dust was used and Fe:H 2O 2 > 1:5, Cl release was higher than the one expected from T.O.C. removal.