Combined technology of SDS-CuO/TiO2 photocatalysis and sequencing batch reactor (SBR) were applied to treating dyestuff wastewater. Photocatalysis was carried out in a spiral up-flow type reactor as pre-treatment. S...Combined technology of SDS-CuO/TiO2 photocatalysis and sequencing batch reactor (SBR) were applied to treating dyestuff wastewater. Photocatalysis was carried out in a spiral up-flow type reactor as pre-treatment. SDS-CuO/TiO2 photocatalyst was prepared by modification of nano-TiO2 using CuO and sodium dodecyl sulfate (SDS). Results show that the SDS-CuO/TiO2 photocatalyst contains two kinds of crystals, including TiO2 and CuO. The band gap of this photocatalyst is 1.56 eV, indicating that it can be excited by visible light (2〈794.87 nm). And characterization also shows that there are alkyl groups on its surface. It takes 40 rain to improve the biodegradability of dyestuff wastewater. Five-day biochemical oxygen demand (BODs) and dehydrogenase activity (DHA) of wastewater reach the maximum value when dissolved oxygen is higher than 2.97 mg/L. SBR reactor was used to treat this biodegradability improved wastewater. Chemical oxygen demand (COD) and colority decline to 72 mg/L and 20 times, respectively, when the sludge loading is 0.179 kg(COD)/[kg(MLSS)'d], dissolved oxygen is 4.09 mg/L and aeration time is 10 h.展开更多
Sodium fluoride and high specific area silica were synthesized by using sodium hexafluorosilicate(Na2Si F6) and sodium carbonate decahydrate(Na2CO3·10H2O). The influencing factors of react temperature, contact ti...Sodium fluoride and high specific area silica were synthesized by using sodium hexafluorosilicate(Na2Si F6) and sodium carbonate decahydrate(Na2CO3·10H2O). The influencing factors of react temperature, contact time, sodium dodecyl sulfate(SDS) and molar ratio of Na2 Si F6 to Na2CO3·10H2O were investigated. The optimum process involves the reaction of 0.075 mol Na2 Si F6 and 150 m L, 0.225 mol Na2CO3·10H2O(molar ratio of 1:3) at 85 °C for 90 min, and 2.0×10-3 mol sodium dodecyl sulfate(SDS) as additive. The results show that the purities of Si O2 and Na F at extraction yields of 96.5% and 98.0% are 91.0% and 98.6%, respectively. The obtained Si O2 were characterized by X-ray diffraction(XRD), scanning electron microscope(SEM), Fourier transform infrared ray(FTIR), differential scanning calorimetry and thermogravimetric analysis(DSC-TGA), N2 absorption/desorption(BET) and laser particle size analyzer. The result demonstrates that Si O2 particles have a high BET surface area of 103 m2/g, and a mean grain size of 985 nm.展开更多
基金Project(CDJZR11210009) supported by the Fundamental Research Funds for the Central Universities of China
文摘Combined technology of SDS-CuO/TiO2 photocatalysis and sequencing batch reactor (SBR) were applied to treating dyestuff wastewater. Photocatalysis was carried out in a spiral up-flow type reactor as pre-treatment. SDS-CuO/TiO2 photocatalyst was prepared by modification of nano-TiO2 using CuO and sodium dodecyl sulfate (SDS). Results show that the SDS-CuO/TiO2 photocatalyst contains two kinds of crystals, including TiO2 and CuO. The band gap of this photocatalyst is 1.56 eV, indicating that it can be excited by visible light (2〈794.87 nm). And characterization also shows that there are alkyl groups on its surface. It takes 40 rain to improve the biodegradability of dyestuff wastewater. Five-day biochemical oxygen demand (BODs) and dehydrogenase activity (DHA) of wastewater reach the maximum value when dissolved oxygen is higher than 2.97 mg/L. SBR reactor was used to treat this biodegradability improved wastewater. Chemical oxygen demand (COD) and colority decline to 72 mg/L and 20 times, respectively, when the sludge loading is 0.179 kg(COD)/[kg(MLSS)'d], dissolved oxygen is 4.09 mg/L and aeration time is 10 h.
文摘Sodium fluoride and high specific area silica were synthesized by using sodium hexafluorosilicate(Na2Si F6) and sodium carbonate decahydrate(Na2CO3·10H2O). The influencing factors of react temperature, contact time, sodium dodecyl sulfate(SDS) and molar ratio of Na2 Si F6 to Na2CO3·10H2O were investigated. The optimum process involves the reaction of 0.075 mol Na2 Si F6 and 150 m L, 0.225 mol Na2CO3·10H2O(molar ratio of 1:3) at 85 °C for 90 min, and 2.0×10-3 mol sodium dodecyl sulfate(SDS) as additive. The results show that the purities of Si O2 and Na F at extraction yields of 96.5% and 98.0% are 91.0% and 98.6%, respectively. The obtained Si O2 were characterized by X-ray diffraction(XRD), scanning electron microscope(SEM), Fourier transform infrared ray(FTIR), differential scanning calorimetry and thermogravimetric analysis(DSC-TGA), N2 absorption/desorption(BET) and laser particle size analyzer. The result demonstrates that Si O2 particles have a high BET surface area of 103 m2/g, and a mean grain size of 985 nm.