Ia. Balcioglu et Y. Inel, PHOTOCATALYTIC DEGRADATION OF ORGANIC CONTAMINANTS IN SEMICONDUCTOR SUSPENSIONS ADDED H2O2, Journal of environmental science and health. Part A: Environmental science and engineering, 31(1), 1996, pp. 123-138
The photocatalytic oxidation of aqueous solutions of phenol, p-nitroph
enol, 4-chlorophenol, aniline, hydroquinone and pyridine have been stu
died in gas recycling reactor utilizing TiO2 as photocatalyst in the p
resence and in the absence of hydrogen peroxide. The rate of oxidation
of organics to CO2 was measured by using natural and artificial near
u.v. light. The disappearance of each solute obeys pseudo first order
kinetics with respect to organic whereas the rate of mineralization is
zeroth order. While the addition of small amounts of hydrogen peroxid
e significantly enhanced the photomineralization rate of all organic c
ompounds, high concentration of it inhibited the reaction. The optimum
concentration of H2O2 ranges from 1x10(-2) to 0.5x10(-2) M for 10(-4)
M organic solutions. The complete mineralization for 10(-4) M of each
organic resulted in approximately 50-110 minutes whereas this period
was shortened to 6-28 minutes by the addition of an optimum amount of
H2O2.