Evaluation and testing of a novel photocatalytic reactor with model water pollutants.

Semiconductor photocatalysis is a newly emerging technology for the elimination of harmful chemical compounds from air and water. It couples low-energy ultraviolet light with semiconductors acting as photocatalyst and thereby overcoming many of the drawbacks that exist for the traditional water treatment methods. Recent literature has established the potential of this powerful technology to destroy toxic pollutants dissolved or dispersed in water. However, to date, very few viable pilot plants exist using this technology. In this study, the application of photocatalysis for the removal of contaminants from waste water discharges such as produced water from oil rigs and other organic contaminants in industrial wastewater, were investigated. A novel photocatalytic reactor, which employs a commercial pellet titanium dioxide (TiO2) catalyst, was tested for water treatment capability by investigating the photocatalytic degradation of contaminants from waste water discharges such as; hydrocarbons in produced water from the oil industry and synthetic dyes from the textile industrys waste processing fluids, using titanium dioxide (TiO2) as photocatalyst in an aqueous suspension under UV irradiation. Experiments were conducted to investigate the effects of parameters such as catalyst loading, pollutant adsorption rate on the pellet TiO2 catalyst and reactor circulation flow rate. In this work, the batch adsorption of methylene blue from aqueous solution (10M) onto the Hombikat-KCO pellet TiO2 catalyst was studied, adsorption isotherms and kinetics were determined from the experimental data. A modest catalyst loading of 30g per 1L TiO2 was choosen for further experiments since its shows gradual and consistent degradation results and approximately 98% degradation of methylene blue was achieved within 60 minutes irradiation in the optimization experiment. Photodegradation of methylene blue dye was monitored by UV- spectroscopy. Complete degradation of methylene blue was achieved within 60 minutes illumination with the various loads of catalyst (30-200g). Experimental results indicate that this novel reactor configuration has a high effective mass transfer rate and UV light penetration characteristics. The use of TiO2 Hombikat KOC pellets catalyst means the system is free from the need of filtration of catalyst following photocatalysis and provides a higher surface area for catalyst illumination and a high contact of catalyst surface area with contaminated water