Photocatalytic mineralisation of mercaptans as environmental pollutants inaquatic system using TiO2 suspension

The photocatalytic oxidation of aqueous solutions of 2-mercaptobenzothiazol e (MBT), 2-mercaptobenzinlidazole (MBI), 2-mercaptobenzoxazole (MBO), 2-mer captopyridine (MP), para-tolylmercaptan (PTM) was investigated over a heter ogeneous catalyst of TiO2, in a photocatalytic reactor. The effect of some physical and chemical parameters such as amount of catalyst, flow of oxygen , pH and time of irradiation were studied in order to optimise the process. These mercaptans are almost completely mineralised to carbon dioxide, ammo nia and sulphate ion by photocatalytic method. The results obtained from ph otocatalytic oxidation of MBT have led us to propose a compound with the su m formula of benzothiazol-2-sulfonate (BTSO3) to be a main intermediate. (C ) 2001 Elsevier Science B.V. All rights reserved.