Hydrothermal Conversion of Triclosan—The Role of Activated Carbon as Sorbent and Reactant

Autor: Barbara Weiner, Sarah Sühnholz, Frank-Dieter Kopinke
Rok vydání: 2017
Předmět:
Zdroj: Environmental Science & Technology. 51:1649-1653
ISSN: 1520-5851
0013-936X
DOI: 10.1021/acs.est.6b05314
Popis: Triclosan (TCS) was treated under hydrothermal conditions at 240 °C for 4 h, either dissolved in aqueous solution or preadsorbed onto activated carbon (AC). Hydrothermal conversion of dissolved TCS led to formation of 2,8-dichlorodibenzo-p-dioxin (DCDD). Its yield was dependent on the pH of the aqueous solution increasing from 38% at pH 4 up to 67% at pH 12. Adsorption of TCS at neutral pH on three different kinds of ACs, powder, granular, and felt, changed the reactivity of the TCS molecule under hydrothermal conditions significantly. The conversion of TCS and, in particular, the formation of DCDD was inhibited in the presence of ACs. When TCS was adsorbed on powdered AC, the preferred reaction pathway was the reductive hydrodechlorination. The findings described herein may be valuable for a potential regeneration method for loaded AC based on hydrothermal treatment.
Databáze: OpenAIRE