Preparation And Studies On The Properties Of Supported Cuprous Oxide

Semiconductor photocatalysis is the ideal technology to bring the pollution undercontrol in the21st century. Currently this environmentally friendly high-technologyreceives extensive attention of the researchers from all over the world. Supportedphotocatalyst also gets the favour of the researchers for loadtype materials can reducethe particles conglomerating and can be reused.The composite photocatalyst was prepared with five water copper sulfate(CuSO4·5H2O) and anhydrous sodium sulfite (Na2SO3) as raw materials, artificialzeolite, silica power and gamma aluminum oxide as its carrier in acetic acid sodiumacetate buffer solution (HAC-NaAC) during the chemical precipitation process. X-raydiffraction (XRD) analysis showed the the main phases of the samples were cuprousoxide and carrier; Scanning electron microscope (SEM) was used to analyse themorphology and grain size of the samples, results showed the cuprous oxideregularly whisker grew on the surface of carriers, and the width of the whisker wasbetween0.1~0.5μm. UV-visible diffuse reflectance analysis showed that the samplesabsorbed light in visible range. The effect factors for the purity and morphology of thesupported cuprous oxide were analyzed. The experimental results show that thesupported cuprous oxide had a good photocatalytic degradation effect of the methylorange, and the optimum experimental conditions were the buffer solution adding intothe sodium sulfite solution；the copper sulfate concentration was0.05mol/L when thezeolite content of0.5g/L；silicon powder and alumina content was0.8g/L and0.6g/Lwhen copper sulfate concentration was0.05mol/L；the temperature was85℃；thereaction time was180min. The EDTA complexometric titration measured the contentof cuprous oxide in zeolite-Cu2O, silicon powder-Cu2O, Al2O3-Cu2O with68.62%,63.19%and65.66%respectively.Methyl orange (MO) as a aze dye with the characteristics of poor degradability and high colour could be imitated the printing and dyeing wastewater. Under theirradiation of imitation solar light, the effects of time, initial concentration and pH ofmethyl orange (MO) and temperature on the degradation efficiency were investigated.The degradation experimental results showed that the optimum experimentalconditions were MO initial concentration of25mg/L, pH value of7.00~10.00andtemperature of40℃. Under the optimum degradation condition, the degradation wasfast before30min, and the degradation curve of the supported cuprous oxide tendedto the balance after30min irradiation, then the degradation with the adding ofzeolite-Cu2O, silicon powder-Cu2O, Al2O3-Cu2O was all above89%, while thedegradation with the adding of pure cuprous oxide was only52.3%, the degradationrate with the addition of the four samples was91.17%,91.81%,92.85%and66.41%after70min irradiation. This contrast test showed that the properties of the sampleswere influenced by the morphology. The reusable experimental results indicated thatzeolite-Cu2O had a good photocatalytic activity and stability in the visible light regionfor after using four times the degradation also was high, and after70min irradiationthe degradation was from92.32%down to91.17%,88.84%,86.58%respectively. Ioninterference experiment showed chloridion (Cl-), fluorinion (F-) and sulfate ion (SO42-)had more obvious influence on the degradation of methyl orange. In order to improvethe biodegradation efficiency the concentration of Cl-, F-and SO42-should becontrolled within1.2g/L,0.3g/L and0.3g/L respectively.