Anionic dodecyl sulfate (DS-) surfactant proved to be an efficient hole scavenger in the TiO2-mediated photocatalytic reduction of Hg(II) in aqueous solution. While oxygen did not affect the efficiency of mercury deposition in this system, chloride ions strongly hindered it, owing to the formation of anionic chloromercurate(II) complexes. Also pH significantly influenced the reduction of Hg(II): an increase of pH in the range 4.5-6.8 dramatically enhanced the efficiency. The presence of Hg(II) considerably accelerated the oxidative degradation of dodecyl sulfate. This reaction was moderately promoted upon increasing the pH; thus, a neutral or a slightly basic reaction mixture was most suitable for simultaneous removal of Hg(II) and DS-. Cationic cetyltrimethylammonium (CTA+) detergent also acted as a hole scavenger but less efficiently than DS -. Its photocatalytic degradation, however, was hindered by Hg(II).
- Titanium dioxide
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry
- Polymers and Plastics
- Colloid and Surface Chemistry
- Materials Chemistry