Photochemical Studies on Degradation of Cetyl Pyridinium Chloride (Cationic Surfactant) in Aqueous Phase Using Different Photocatalysts

The photocatalytic process using semiconductors with a nanostructure is one of the technologies usedfor the destructive oxidation of organic compounds such as surfactants. In this paper, thephotocatalytic degradation of Cetyl pyridinium chloride (CPC), was investigated in aqueous phaseusing various semiconductors such as titanium dioxide (Ti02), zinc oxide (ZnO), stannic oxide(Sn02). The degradation was studied under different conditions including the amount ofphotocatalyst, pH of the system, initial concentration and presence of anions. The results showed thatthe photocatalytic degradation of CPC was strongly influenced by these parameters and the bestconditions for the photocatalytic degradation of CPC were obtained. The experimental resultsindicated that maximum degradation (87%) of surfactant occurred when ZnO was used as catalyst.The photodegradation efficiency was enhanced by increasing amount of photocatalyst, and decreaseswith the increase in the initial concentration of Cetyl pyridinium chloride. Finally, the kineticsprocess was studied and the photodegradation rate of CPC was found to obey pseudo-first-orderkinetics equation represented by the Langmuir—Hinshelwood model.