Title
Efficiency in electro-Fenton oxidation of CTMP pulping wastewater
Authors
QIANG ZHAO XUEMING ZHANG DEZHI SUN XIAOJUAN JIN and ZHAOHONG WANG

Received December 1, 2017
Published Volume 52 Issue 9-10 October-December
Keywords Fenton oxidation, electro-Fenton, CTMP, preimpregnation wastewater, FTIR

Abstract
Wastewater originating from chemithermomechanical pulping (CTMP) contains various organic compounds and therefore it is difficult to treat. To increase the effect of oxidation, the electro-Fenton process was employed in this study. Fenton’s reagent (H2O2 and Fe2+) was produced by simultaneous reduction of O2 and Fe3+ on a stainless cathode in an acidic medium. Electrochemistry combined with Fenton’s reagent provides the hydroxyl radical, a powerful oxidant. The chemical oxygen demand (COD) removal efficiencies and the turbidity of electro-Fenton oxidation on preimpregnated wastewater of CTMP were investigated. The optimal electro-Fenton oxidation conditions were determined as follows: pH 4, applied voltage of 12 V, current of 0.2 A, electrode space of 2 cm and aeration gas flow of 16 L/h. The CODcr removal rate could reach 40.1% and the turbidity removal rate achieved by the aforementioned electro-Fenton process was 49.9%. Fourier transform infrared spectroscopy showed that electro-Fenton oxidation induced higher degradation of preimpregnated wastewater of CTMP than Fenton oxidation alone.