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Degradation of phenol by photocatalytic
oxidation Phenol
is a major environment contaminated from various industries such as coke, pesticides,
insecticides, fungicides and dyes due to high toxicity on the skin, eyes and mucous
membrane in humans. Industrial wastewater containing phenols are conventional treated by
FeSO4 and H2O2 to oxidize phenol to CO2 and H2O.
FeSO4 is converted to Fe2(SO4)3 and H2O2
is decomposed and then the reactants could not be recycled. In addition the ferric sulfate
is dumped and water is not reused. A new process was developed based on treatment with V2O5
- SiO2 photocatalyst or ozone in presence of UV light. The process is
advantageous as the photocatalysts could be recycled and water could be reused. The
process was successfully applied for treatment of wastewater produced from coke plant. The
percent degradation of the phenol is increased from 47.31 to 72 % using V2O5
- SiO2 xerogel loading from 0.333 to 1.333 wt. % in presence of UV light. The
rate constant was increased from 0.0025 to 0.0036 min-1 using different V2O5
- SiO2 xerogel loading and the reaction kinetics were found to be first order.
On the other hand, the optimum conditions of photocatalytic degradation of phenol using
ozone were obtained as the following: 1.6 wt. % ozone concentration and 0.85 m3/h
airflow. The phenol removal efficiency using these conditions was 99% and the reaction was
found to obey first order reaction. |
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