The Study On Visible Light Catalytic Degradation Of BPE Using Nanometre Cu₂O And Nanometre α-Fe₂O₃

Environmental endocrine disruptors is called Environmental Hormone which is a kind of synthentic chemical and has similar effects of estrogen that can interfere endocrine mechanism, cause endocrine imbalance, and also affect the safety and health of human and wildlife seriously. Phenolic compounds are kinds of organic pollutants which is to detect by US EPA preferentially. BPE is the typical representative of phenolic compound, Its biological toxicity is equivalent to Bisphenol A which exists widely in daily lives. As most of endocrine disruptors are fat soluble component, they can accumulate in living bodies easily and enrich in ecosystem through the food chain. However, the traditional water treatment methods are difficult to remove them from the environment effectively. Therefore, to research and develop new treatment methods on environmental endocrine disruptors has been becoming an important direction of the research on environmental endocrine disruptors.Semiconductor photocatalysis react can be carried out under normal temperature and pressure. Simple operation, wide range of applications, avoiding secondary pollution, no massive other substances except light and catalyst, and reducing the consumption of energy and raw materials, all of them are the advantage of the semiconductor photocatalysis.After the test of liquid chromatography,it can conclude optimum condition: (1)chromatographic column C—18:PNA2000—250×0.46; detector: UV detector (PDA); (2)wavelength: 230nm; (3)mobilephase: acetonitrile/water (V/V) = 65/35; (4)speed :0.4ml/min; (5)quantity:10μL; (6)temperature:room temperature.Considering nano-Cu₂O and nano-Fe₂O₃ semiconductor visible light with higher catalytic activity and stability, the experiment adopted them as photocatalysis and to study the performance of degrading Bisphenol E in a simulated natural light. In experiment, nano-Cu₂O is prepared by hydrolysis method the other photocatalysis nano-Fe₂O₃ is prepared by new combustion synthesis. Nano-Cu₂O and nano-Fe₂O₃ prepared can be characterized via x-ray diffraction meter and electron microscope.It can conclude that the catalyst is nano-catalyst, and it also can result that that high purity nano-Cu₂O particles can be prepared by hydrolysis method and get the best conditions to prepare nano-Fe₂O₃- the ratio of Fe (NO3) 3 and polyvinyl is 4:1,after 1.5 h under the 500℃calcination, it conclude thatα—Fe₂O has the best effective for BPE.Choosing 250W metal halide lamp as simulate natural light and using high performance liquid chromatograph to determine the solution after photocatalysis reaction, analysises and investigates the photodegradation efficiency of the BPE by nano-Cu₂O and nano- Fe₂O₃ in visible light in the experiment. It study the influences of illumination time, initial concentrations of BPE, initial pH value, the conditions of catalyst and H₂O₂ to the photodegradation efficiency. At the same time, it test the electric conductivity changes of the process.The conclusion shows: using Cu₂O as catalyst, after 120minutes irradiation, the best photodegradation efficiency of BPE reaches 86.84% under the conditions of C₀ (Cu₂O) =0.4g/L, C₀ (H₂O₂) = 7.5mL/L, C₀ (BPE) =10.0mg/L and pH=5.0. In the process, the electric conductivity changed obviously from 2.21μs/cm to 8.98μs/cm; when using nano-Fe₂O₃ as catalyst, after 150 minutes irradiation, the best photodegradation efficiency of BPE reaches 46.66% under the conditions of C₀(Fe₂O₃)=0.6g/L, C₀(H₂O₂)= 10mL/L, C₀ (BPE)=5.0mg/L and pH=3.8-4.2. In the process, the electric conductivity changed from 2.21μs/cm to 5.85μs/cm.In this experiment, comparing with photo degradation efficiency of BPE when using nano-TiO₂ as catalyst, under the conditions of C₀ (BPE) =10.0mg/L, pH=3.8-4.2 and C₀ (H₂O₂) =10mL/L, changing the dosaging quantity of TiO₂, the best photo degradation efficiency of BPE reaches 25.73% .With the comparisons of kinetic study of Cu₂O,α—Fe₂O₃ and TiO₂ for photodegradation efficiency of BPE, the catalytic reactions conform pseudo-first-order kinetic equation. The three kinds of catalyst on photo degradation efficiency of BPE in a simulated visible light are in order: Cu₂O,α—Fe₂O₃,pure TiO₂.