| TiO2 photocatalytic in environmental protection, water and gas organic and inorganic pollutants contral has made considerable progress, and it is considered a great depth of the environmental future of purification technology. We introduced the easy and simple method of improving the light intensity to realize the quick and efficient degradation of the refractory organic pollutants, since there are several problems in traditional ultraviolet photocatalytic technique as follows: its reactions require long time and the reaction rate is low. The suggested method was an efficient method to treat refractory pollutions. It overcomes the defection that the degradation efficiency for refractory pollutions by traditional ultraviolet photocatalytic technique is low.In the present article, firstly, the photocatalytic performance under very high intensity UV radiation were investigated by decolorization of methylene blue(MB). The reaction rate was increased and the reaction time was shorted by improving the UV photon flux. Then the method is applied to photocatalytic degradation of Dichloroacetic Acid. With the comparison between photocatalytic degradation of Dichloroacetic Acid under very high intensity UV and photocatalytic under the low intensity UV radiation though four aspects–degradation percentage and reaction time, reaction rate, quantum efficiency and energy consumption, the both advantages and defects of them are pointed out. At the same time, under the high intensity UV radiation, the effect of UV photon flux, the reactant initial concentration, catalyst loading on the reaction rate were also analysised.The photocatalytic performance under very high intensity UV radiation was investigated by decolorization of methylene blue (MB). Results show that the employment of high intensity UV radiation, as the photon flux range from 1.43×10-6 einstein cm-2s-1 to 3.13×10-6 einstein cm-2s-1 , and selection of optimal operational parameters can leads to a increase in the reaction rate remarkably and make the reaction time shorten in 30 seconds, as the initial MB concentration was 20mg L-1. The first-order rate constant increase linearly with increase of the photo flux for the studied range of photo flux. It can be seen from the results that the photon flux have great impact on the reaction rate of photocatalytic degradation MB. And the photon flux is the the key factors which influence the reaction rate. It can increase the reaction rate substantially, and shorten the reaction time.The very high intensity UV radiation and low intensity UV radiation were used to photocatalytic degradation of Dichloroacetic Acid. The comparison show that the decomposition percentage of DCA is above 99% in 30 seconds under the studied range of photo flux, as the initial MB concentration was 20mg L-1. And the time how long it will take to make the degradation-rate of DCA to got up to 90% under the high photon flux range is 1/180 that under the low photon flux range from 3.11×10-9 einstein cm-2s-1 to 1.42×10-9 einstein cm-2s-1. The reaction rate is 4 orders higher than that under the low intensity UV radiation. The quantum efficiency of photocatalytic under the high intensity UV radiation is lower than that under the low intensity UV radiation, but the degradation percentage is higher, it need a shorter UV radiation time and lower energy consumable.Under the high intensity UV radiation, the effect of UV photon flux, the reactant initial concentration and catalyst loading on the reaction rate were also analysised. The result show that with the aim of the most degradation, the moderate and the suitable conditions were photon flux 3.13×10-6 einstein cm-2s-1; DCA concentration 20mg L-1; catalyst concentration 1g/L. And TOC concentration proved that the reaction of DCA photocatalytic degradation under the high light intensity irradiation has no stable intermediates.It can be seen from the results that the photon flux have great impact on the reaction rate of photocatalytic degradation DCA. And the photon flux is the the key factors which influence the reaction rate. It can increase the reaction rate substantially. The suggested method will give a new thought and approach to the removal of other disinfectant by-products.
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