Summary: | 碩士 === 元智大學 === 化學工程研究所 === 88 === Catalytic oxidation reaction is a process that achieves a maximum utilization of oxygen in a catalytic environment. In the present research, the activated carbon fiber (ACF) and ozone were combined to achieve a maximum efficiency of the catalytic oxidation process by capitalizing the adsorption and catalytic oxidation capabilities of ACF.
In the batch experimental test, investigations were made to examine the treatment efficiencies of industrial wastewater by such a process under various operating conditions including the ozone mass flow rate, amount of ACF and pH. In the continuous tests, chemical coagulation was adopted as a pretreatment measure of the industrial wastewater. Test results indicated that chemical coagulation offers an efficient means for complimenting the catalytic oxidation reaction process.
Multi-factor experimental design was employed in the present study to help search for the optimal operating conditions that include the mixer speed, amount of ACF, ozone mass flow rate and the reaction time. Analysis of experimental design showed that the effects of these four operating variables are strong with 99 % confidence. However, the interactions of these four variables on the treatment efficiency are not evident. The multi-factor response surface equation obtained from the experimental tests permitted easy determination of optimal operating conditions.
Kinetic studies were also attempted to investigate the reaction mechanism of the catalytic oxidation process. Several kinetic models, including exponential, Lumped, generalized and complex kinetics, were considered for describing catalytic oxidation reaction. The generalized and complex kinetics were found to represent well the reaction process.
For process scale-up and reactor design, dimensionless analysis was made to correlate the power number and the mixer speed. The dimensionless correlation allows easy scale-up of experimental apparatus. Test results shows that the correlation is represented by two line segments that join at a critical mixer speed for gas induction onset. Other related aspects, like gas holdup, in the liquid phase were also studied in the experimental tests.
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