Heterogeneous photocatalysis for environment remediation: Case studies in gas-solid and liquid-solid regimes

During these last decades many applications of heterogeneous photocatalytic reactions have been reported in gas-solid and liquid-solid systems both fo r inorganic and organic pollutants' abatement. In this paper some case stud ies, i.e. the photocatalytic oxidation of toluene in gas-solid phase by usi ng TiO2 as the catalyst, the photocatalytic oxidation of cyanide ions in aq ueous suspensions of TiO2 and the photocatalytic oxidation of phenol by usi ng mixed WO3/WS2 powders in liquid-solid phase are reported. Moreover the p ossibility of coupling the photocatalytic method with the use of membranes is presented for the 4-nitrophenol photodegradation carried out in aqueous medium.