Environmental remediation using catalysis driven under electromagnetic irradiation

Photocatalytically reductive dehalogenation using nano-sized semiconductors such as ZnS and CdS nanocrystallites under respective UV (lambda > 300 nm) and visible light (lambda > 400 nm) irradiation is emphasized as a novel methodology for detoxification of halogenated organic compounds under mild conditions. Nano-sized ZnS and CdS can supply the compounds with photoexcited electrons of high reduction potentials. This photocatalytic dehalogenation is so selective that it gives no other products than the dehalogenated compounds. Microwave-assisted catalytic dehalogenation of halogenated organic compounds shows distinguished characteristics in rapid and complete detoxification, i.e., the selective heating and energy-saving when compared to conventional heating. Predominance of reductive dehalogenation performed in the above two systems is relieved in comparison with other reductive and oxidative techniques as detoxification methods.