A comparative study of HO center dot- and SO4 center dot--based AOPs for the degradation of non-ionic surfactant Brij30


Kabdasli I. , ECER C., OLMEZ-HANCI T., TUNAY O.

WATER SCIENCE AND TECHNOLOGY, vol.72, no.2, pp.194-202, 2015 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 72 Issue: 2
  • Publication Date: 2015
  • Doi Number: 10.2166/wst.2015.204
  • Title of Journal : WATER SCIENCE AND TECHNOLOGY
  • Page Numbers: pp.194-202

Abstract

In the present study aqueous solutions of Brij30, an alcohol ethoxylate surfactant, were photocatalytically and photochemically treated by employing the TiO2/UV-A, H2O2/UV-C and persulfate (PS)/UV-C processes. During TiO2/UV-A treatment, even in short reaction periods (10 minutes), high rates of Brij30 removals were achieved; however, longer experiment periods (240-480 minutes) were needed in order to obtain notable total organic carbon (TOC) removals. Increasing the TiO2 dosage exhibited a positive effect on treatment efficiencies. For initial pH value of 3.0, increasing the TiO2 dosage from 1.0 to 1.5 g/L resulted in an improvement in Brij30 removal from 64% to 79% after 10 minutes whereas 68 and 88% TOC removals were observed after 480 minutes, respectively. Brij30 removal was very fast and complete via both H2O2/UV-C and PS/UV-C treatments, accompanied with significant mineralization rates ranging between 74 and 80%. Toxicity assessed by Vibrio fischeri, was found to be similar to that of the original Brij30 solution during H2O2/UV-C treatment, while in the PS/UV-C process, the relative inhibition of Brij30 towards V. fischeri fluctuated throughout the treatment and eventually non-toxic products were formed by the oxidation of SO4 center dot- radicals.