Date of Award
1995
Degree Type
Dissertation
Degree Name
Doctor of Philosophy
Abstract
The {dollar}\rm TiO\sb2{dollar} photocatalytic degradation and mineralization of organic pollutants in water has been broadly demonstrated at the laboratory level for a wide number of organic pollutants. However, there are still some problems that need to be addressed in order to make this technology more practical. The design of heterogeneous photocatalytic reactor systems, still in the infancy of their development, is facing different problems such as light scattering, oxygen starving, particle separation and mass transfer. Additionally, there have also been a lack of a general method to evaluate the performance of the different reactor systems.;The present work addresses these problems by presenting a new photoreactor system (PHOTO-CREC II) and a general method called the Photochemical Thermodynamic Efficiency Factor, PTEF (based on known thermodynamic and photocatalytic principles) for the evaluation and comparison of the performance of different photoreactor systems.;The new photocatalytic reactor concept (PHOTO-CREC, reactor) was designed, built and successfully tested with model pollutants (Methylene Blue and Phenol). The characteristic parameters of adsorption and reaction kinetics for the photodegradation of methylene blue were determined. The effects on the reaction rate of initial concentration of the model compound, flow rate of the solution through the reactor and light intensity were also determined and a kinetic model proposed. Quantum yields and EE/Os for the photodegradation reaction were determined and compared with other values reported in the literature.;The new efficiency index (PTEF), was utilized to compare the performance of the PHOTO-CREC reactor with other photoreactor systems. It was demonstrated that PTEFs, obtained using data from a number of literature references, are independent or weakly dependent on pollutant chemical structure and characteristic of the specific photocatalytic reactor used.;PTEF values in PHOTO-CREC II were in the range of {dollar}1\times10\sp{lcub}-9{rcub}{dollar} mol {dollar}\rm J\sp{lcub}-1{rcub},{dollar} which is considered in the high range for PTEF values. This was particularly relevant considering that the unit studied was with the largest volume for this range of PTEF.
Recommended Citation
Valladares, Julio E., "A New Photocatalytic Reactor For The Photodegradation Of Organic Contaminants In Water" (1995). Digitized Theses. 2513.
https://ir.lib.uwo.ca/digitizedtheses/2513