![]() The coupled activation of photochemical and photocatalytic reactions by using of two different types of radiation, microwave and UV/Vis, is covered by the new discipline called microwave photochemistry and photocatalysis. Oxidation products of photodegradation of PBDEs were not observed likely due to the low intensity of UV irradiance. In spite of the use of titania oxide coated electrode emitting UV-vis irradiation and at the presence of water, the prevailing mechanism of photodegradation of PBDEs was probably photolysis. Lower brominated congeners, including tri-brominated congener BDE28, were determined. Similarly, the pathway of PBDE photodebromination by successive losses of bromine atoms was confirmed as the main initial pathway, in some cases also influenced by PBDE substitution patterns. The rate of BDE209 congener debromination was high and reaction efficiency after 240 minutes of BDE209 dehalogenation exceeded 99% even with high concentrations of 10 000 ng/mL. Positive microwave effects (probably only heat effects) compensate relatively low irradiance intensity of UV/Vis generated in a microwave field. This method enhances penetration of UV/Vis light. A novel electrodeless discharge lamp coated with titania oxide (anatase) and placed in a microwave field directly in a bulk of suspension was used to generate UV/Vis radiation. (c) 2012 Society of Chemical Industryĭegradation of decabromodiphenyl ether (BDE209) dissolved in n-hexane and in the mixture of n-hexane with water and microglass beads using microwave assisted photoreaction was examined. The MCAA photodegradation process with titania-coated Hg-EDLs can be enhanced in the TiO2/UV/MW system. Conclusions It was found that additional operational parameters had important effects on photocatalytic efficiency in a microwave field. Inhibition of MCAA photodegradation was observed in the presence of CO32 and SO42 anions, whereas the effect of NO3 was negligible. Photocatalytic reaction of MCAA was favoured at higher temperature mainly owing to thermal dependence of the Hg-EDL light intensity on the 366 nm line. Coupled UV/MW irradiation led to effective photodegradation at higher MCAA concentration at an optimum value of 0.15 mol L1. ![]() The photocatalytic process was monitored by the change in concentration of Cl in the solution. Results Studies were carried out in atmospheric or low-pressure batch type microwave photocatalytic reactors. initial MCAA concentration, reaction temperature, and the presence of inorganic anions) on the photocatalytic degradation of aqueous mono-chloroacetic acid (MCAA) in a microwave field are discussed. Effects of additional operational parameters (i.e. ![]() Background Mercury electrodeless discharge lamps (Hg-EDLs) coated with titania in the form of thin films were used to generate UV/Vis radiation when placed in a microwave field. ![]()
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