Features and efficiency of some platinized TiO2 photocatalysts.

C. A. EMILIO; J. J. TESTA; D. HUFSCHMIDT; G. COLÓN; J. A. NAVÍO; D. W. BAHNEMANN; M. I. LITTER

JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY

KOREAN SOC INDUSTRIAL ENGINEERING CHEMISTRY

Lugar: Seoul; Año: 2004 vol. 10 p. 129 - 138

1226-086X

Three commercial powdered photocatalysts, Degussa P25 (P25), Sachtleben Hombikat UV100 (UV100) and Millennium TiONA PC 50 (PC50) have been platinized to incorporate 0.5 and 1 wt.% Pt on the surface of the particles. The physicochemical properties (SBET, particle size, morphology of the particles, etc.) have been measured and compared among the samples. The photocatalytic efficiency has been tested with two environmentally important oligocarboxylic acids, EDTA and NTA (5 mM). No strong differences could be observed among the catalysts in the case of EDTA, and an inhibition was observed in all cases. A striking effect of platinization has been observed in the case of NTA degradation, with a change in the kinetics from zero order in the pure precursors to first order in the platinized samples. Pure and platinized HB samples were the best photocatalysts for NTA. An optimum Pt amount (0.5 wt.%) was observed for the photoefficiency of the samples. It can be concluded that the efficiency is more dependent on the nature of the substrate to be degraded than on the physicochemical properties of the samples.