TiO2 modified by salicylic acid as a photocatalyst for the degradation of monochlorobenzene via Pickering emulsion way

Pickering emulsion could be a new way for the enhancement of the photocatalysis process efficiency, in particular when applied to degrade non-soluble organic pollutants. To validate this idea, Pickering emulsions were prepared by using monochlorobenzene (MCB) as a model organic contaminant of low solubility in water and TiO2 modified by salicylic acid (SA) as stabilizer. XRD, TEM, TGA, XPS and FTIR were used to characterize the fine solid particles of TiO2–SA. Electrical conductivity and optical microscopy were used to characterize emulsions. We focused to prepare emulsions of small drop size by varying the pH of continuous phase (water), the weight fraction of solid particles and the emulsification process. The as-prepared emulsions were photocatalytically degraded under visible radiation. The removal rate of MCB was measured by UV/vis spectroscopy. The results proved that use of a Pickering emulsion stabilized by TiO2–SA nanoparticles provides an effective and novel way to intensify the photocatalytic degradation of the organic contaminant.