悬浮型光催化纳滤膜反应器处理H酸废水光催化降解效率及反应动力学

分别采用悬浮型光催化反应器和悬浮型光催化纳滤膜反应器进行光催化降解H酸溶液试验。结果表明,后者比前者具有更好的光催化处理效果。在污染物初始质量浓度分别为50 mg/L、100 mg/L和150 mg/L、ρ/ρ0≥0.7的反应条件下,悬浮型光催化反应器中污染物光催化降解过程分别遵循L-H一级、一级以及一级与0级耦合的反应动力学。而在悬浮型光催化纳滤膜反应器的耦合工艺中,光催化降解过程分别遵循L-H一级、一级与0级的耦合以及0级反应动力学模型。

氧化锌-氧化铜纳米复合物可见光诱导光催化降解2,4-二氯酚性能（英文）

Nanostructured ZnO and CuO, and coupled oxides, i.e., ZnCu, Zn2Cu, and ZnCu2, with ZnO:CuO molar ratios of 1:1, 2:1, and 1:2, respectively, were successfully prepared through a simple, one-step, microwave-assisted urea–nitrate combustion synthesis, without the use of organic solvents or surfactants. The prepared samples were characterized using X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis, transmission electron microscopy, Fourier-transform infrared spectroscopy, diffuse reflectance spectroscopy, and photoluminescence spectroscopy. The optical absorption of Zn O extended into the visible region after CuO loading. The photocatalytic activities of ZnO, CuO, and the coupled oxides were evaluated based on photodegradation of 2,4-dichlorophenol under visible-light irradiation. The coupled metal oxide Zn2Cu showed the best photocatalytic activity; this was mainly attributed to the extended photoresponsive range and the increased charge separation rate in the nanocomposite. The photocatalytic degradation process obeyed pseudo-first-order kinetics. The results suggest that the coupled metal oxide Zn2Cu has potential applications as an efficient catalytic material with high efficiency and recyclability for the photocatalytic degradation of organic pollutants in aqueous solution under visible-light irradiation.

侧光光纤引导的内源可见光催化降解亚甲基蓝(英文)

The side-glowing optical fibers (SOFs) were chosen as the conducting medium of endogenous light; and 20 mg·L-1 methylene blue was chosen as the target to be degraded. The SOF is made up of quartz core with a silicon cladding, which can emit light through side surface more uniformly and transmit light for longer distance to avoid attenuation of light by liquid medium. The filament lamp was chosen as visible light source. Different reaction conditions, such as the presence of optical fiber or not, the quantity of SOF, light irradiation intensity were tested by measuring the methylene blue degradation of methylene blue. The results show that suitable reaction conditions were 1.167 g·L-1 Ag + /TiO 2 with 7% (by mass) of Ag + doped in TiO 2 , and 500 roots of SOF (30 cm length in solution). The photocatalytic degradation efficiency under 300W lamp irradiation for 8h was about 97%. And the photocatalytic degradation efficiency of methylene blue degradation was proportional to SOF quantity, light irradiation intensity and catalytic dosage within a certain range. Compared with general UV and visible light SOFs could save a huge amount of energy and cost, in the potential applications in dealing with organic pollutants on a large scale.

SiO_2-TiO_2系玻璃光催化降解含铬废水的研究

介绍了SiO2-TiO2系玻璃光催化降解含铬废水的实验。在Cr6+浓度为80mg.L-1、体积为100mL的废水中,投加0.7g SiO2与TiO2的分子比为8∶2的SiO2-TiO2系玻璃,光照反应体系3h,Cr6+去除率达99.9%。

光催化TiO_2薄膜研究进展及其影响因素

提高光催化剂的光催化活性是多相光催化剂能否工业化应用的关键。文章主要介绍了半导体多相光催化材料的理论及应用的发展现状 ,探讨了玻璃表面TiO2 薄膜光催化性能的影响因素及提高其光催化降解效率的途径。

铝板为基础的S掺杂TiO_2催化分解有毒有机气体(英文)

S-doped TiO2(S-TiO2) films were immobilized on flexible low-cost aluminum sheets(S-TiO2-AS) using a sol-gel dipping process and low post-processing temperatures. The photocatalytic degradation of toxic organic vapors using the prepared films was evaluated using a continuous-flow glass tube under visible light exposure. The surface properties of the S-TiO2-AS and TiO2-AS films were examined by scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and ultraviolet-visible spectroscopy. The photolysis of benzene, toluene, ethyl benzene, and xylene(BTEX) did not occur on the bare AS. In contrast, the photocatalytic degradation efficiencies of the target pollutants using S-TiO2-AS were higher than those obtained using reference TiO2-AS photocatalyst. In particular, the average photocatalytic degradation efficiencies of BTEX using S-TiO2-0.8-AS(S/Ti ratio = 0.8) over a 3-h process were 34%, 78%, 91%, and 94%, respectively, whereas those of TiO2-AS were 2%, 11%, 21%, and 36%, respectively. The photocatalytic decompo-sition efficiencies of BTEX under visible irradiation using S-TiO2-AS increased with increasing S/Ti ratios from 0.2 to 0.8, but decreased when the ratio further increased to 1.6. Thus, S-TiO2-AS can be prepared using optimal S/Ti ratios. The degradation of BTEX over S-TiO2-AS depended on the air flow rates and initial concentrations of the target chemical. Overall, under optimal conditions, S-TiO2-AS can be effectively applied for the purification of toxic organic vapors.

纳米TiO_2的改性及应用研究

从提高纳米TiO2 光催化降解效率 ,改变纳米TiO2 的介电性能和改变TiO2 表面活性等三方面对目前纳米TiO2 的改性方法及应用研究进展进行了全面的综述。并对TiO2 的研究进行了展望。

Preparation and photocatalytic performance of ZnO/ZnGa_2O_4 composite microspheres

ZnO/ZnGa_2O_4 composite microspheres with heterojunction were successfully synthesized by one-pot hydrothermal method.These samples were characterized by TG/DTA,XRD,TEM,HRTEM,UV-vis DRS,FL and BET techniques.The results indicated the as-prepared samples showed better degree of crystalline and large specific surface area.The photocatalytic activity was evaluated by degradation of methyl orange with the concentration of 50 mg/L under the irradiation of simulated sunlight.The effects of molar ratio of Zn to Ga and calcination temperature on the photocatalytic activity were investigated in detail.The results showed that the highest photocatalytic degradation efficiency was observed at the molar ratio of Zn to Ga of 1:0.5 in the starting materials and the calcination temperature of 400 °C.The maximum photocatalytic degradation rate of MO was 97.1% within 60 min under the simulated sunlight irradiation,which is greatly higher than that of ZnO and ZnGa_2O_4.

Fabrication and photo-catalytic properties of pure and cation doped TiO_2 nanotube arrays

The highly ordered and vertically oriented pure TiO2 nanotube arrays(TONTAs) are synthesized by anodic oxidation of titanium foils in fluoride-based electrolytes under different temperatures and voltages. Then TONTAs are treated at different temperatures. X-ray diffraction(XRD) patterns show that its structure is anatase at 500 with the ℃ temperature increasing to 700 ℃, the most of anatase will transform to rutile, the nanotube arrays form granular titanium oxide, while at 900 ℃, anatase will transform to rutile completely. The experimental results of photocatalytic degradation of methylene blue solution show that the cobalt-manganese co-doped TONTAs have good photocatalytic degradation efficiency.