Abatement of 4-chloropenol under visible light with peroxymonosulfate (PMS) in presence of Co~(2+)

摘要

The 4-chlorophenol is a highly toxic organic compound present in wastewater, mainly from brokers or chemical byproducts of the petrochemical, paper, plastics and conventional disinfection of drinking water. In the present study evaluated a similar treatment of advanced oxidation technologies involving the degradation of 4-chlorophenol (4-Cl) by peroxymonosulfate (PMS) catalyzed by cobalt (Co+2) and assisted by visible light. To achieve the objective previous degradations were conducted to in order to set the intervals to conduct a multivariate analysis. According to these results experimental design was carried out between the ranges of 50 -100 mg L-1 for 4-Cl, 3,88 - 7,76 mM for PMS and 0,5 - 1 mg L-1 for Co+2, the response factor was the residual 4-Cl concentration after 60 min of irradiation. The design was performed and analyzed using the statistical program MODDE 7.0, resulting in a star-like array of 17 experiments. The polynomial expression and the response surface obtained gave an optimal response study ([4-Cl] = 50 mg L-1 , [PMS] = 7,76 mM and [Co+2] = 1 mg L-1). Under that conditions a total TOC reduction (22 to 0 mg L-1) after 300 minutes, also total COD removal of 124 (0 min) to 0 mg L-1 (300min) and chloride ions 1,7 (60 min) to 0 mg L-1 (120 min). HPLC-MS experiments were conducted to identify degradation intermediates.