Photodegradation of a real textile dyeing wastewater taken from
Hilla textile factory in Babylon Governorate, Iraq have been investigated.
Photocatalytic degradation was carried out over suspensions of titanium
dioxide or zinc oxide under ultraviolet irradiation. Photodegradation
percentage was followed spectrophometrically by the measurements of
absorbance at
?max equal to 380 nm. The rate of photodegradation increased
linearly with time of irradiation when titanium dioxide or zinc oxide was used.
A maximum color removal of 96% was achieved after irradiation time of 2.5
hours when titanium dioxide used at 303K and 82% color reduction was
observed when zinc oxide used for the same period and at the same
temperature. The effect of temperature on the efficiency of photodegradation
of dyestuff was also studied. The activation energy of photodegradation was
calculated and found to be equal to 21 ± 1 kJ mol
-1
on titanium dioxide and
24 ± 1 kJ mol
-1
on zinc oxide