Study On Dye Wastewater Treatment Using UV-CWPO Process

Catalytic wet oxidation technology is an effective way to deal with organicpollutants,but harsh operating conditions(high temperature and pressure) restricts itsindustrial application.Meanwhile,High-concentration wastewater or actual wastewateris treated ineffectively with photocatalytic oxidation technology.Therefore,This paperhas built UV-CWPO system,taken reactive brilliant red X-3B as the simulativepollutant.investigated the degradation effect of the dye, determined the optimumprocess,explored the degradation pathway and mechanism of UV-CWPO throughanalysis of intermediate product,and applied this process in actual wastewater.Single-factor experiments was carried out to inspect the influences of differentfactors on the decolorization rate of reactive brilliant red X-3B.The optimalconditions were confirmed as follows:reaction temperature50℃,reaction time2.5h,catalyst dosage2.5g,H2O2dosage0.6mL,pH4. Orthogonal experiments werecarried on to optimize the technological parameters on the basis of single factorexperiment.The optimum technological conditions was obtained as follows:reactiontemperature60℃, reaction time3.0h,catalyst dosage2.5g,H2O2dosage0.6mL,pH4.The decolorization ratio was99.61%under this situation and the ratio was a littlehigher than that of the single factor experiments.By using detection means such as UV-Vis、IR and GC-MS,the degradationintermediate products of reactive brilliant red X-3B was analysised,and thedegradation path graph was speculated.It turned out that hydroxyl radical firstlyattacked the azo bond and maked it destaining,opend the benzene ring and then smallmolecular substances formed.The degradation mechanism of UV-CWPO process wasalso studied in this paper. The Tert-butanol hydroxyl trapping agent was taken toprove the· OH generation in the degradation process, confirming that thedegradation process followed the radical mechanism. By comparing treatments ofreactive brilliant red X-3B between CWPO process and UV-CWPO process,cooperation effect of photocatalytic oxidation and catalytic wet oxidation wasinvestigated. The process treated wastewater from a factory in Jiangxi province, The treatmenteffects were inspected,the results showed that the technology had preferable treatmenteffect on the wastewater.