目的研究臭氧氧化技术处理酸性红B染料废水的效果,并探讨O3投加量、废水的初始pH值、H2O2和O3物质的量比对臭氧氧化处理酸性红B染料废水效果的影响.方法依据臭氧高级氧化的机理,在实验室反应器中通过实验考察在臭氧氧化处理酸性红B染料...目的研究臭氧氧化技术处理酸性红B染料废水的效果,并探讨O3投加量、废水的初始pH值、H2O2和O3物质的量比对臭氧氧化处理酸性红B染料废水效果的影响.方法依据臭氧高级氧化的机理,在实验室反应器中通过实验考察在臭氧氧化处理酸性红B染料废水过程中,控制不同的O3投加量、废水的初始pH值、H2O2和O3物质的量比对酸性红B染料废水的色度和COD去除率的影响.结果在pH=7的条件下,单一臭氧氧化30 m in时,废水的色度和COD去除率分别为99.5%和37.9%;而废水的初始pH值控制在11左右时,COD去除率有较大提高.O3/H2O2氧化工艺,适宜的H2O2和O3物质的量比为0.6,氧化处理30 m in废水的COD去除率可达53.5%.结论O3高级氧化能够有效降解酸性红B染料废水,在臭氧反应体系中投加H2O2可以明显提高降解速率,缩短处理时间,降低O3耗量.展开更多
Boron- and cerium-codoped TiO2 photocatalysts were synthesized using modified sol-gel reaction process and characterized by X- ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, particle size distribut...Boron- and cerium-codoped TiO2 photocatalysts were synthesized using modified sol-gel reaction process and characterized by X- ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, particle size distribution （PSD）, diffuse reflectance spectra （DRS）, and Brunauer-Emmett-Teller （BET）. The photocatalytic activities were evaluated by monitoring the degradation of dye Acid Red B （ARB）. The results showed that the prepared photocatalysts were mixed oxides mainly consisting of titania, ceria, and boron oxide. The structure of TiO2 could be transformed from amorphous to anatase and then to rutile by increasing calcination temperature; the transformation being accompanied by the growth of particle size without any obvious change in phase structure of CeO2. The XPS of B1.6Ce1.0-TiO2 prepared at 500℃ showed that a few boron atoms were incorporated into titania and ceria lattice, whereas others existed as B2O3. Cerium ions existed in two states, Ce^3＋ and Ce^4＋, and the atomic ratio of Ce^3＋/Ce^4＋ was 1.86. When boron and cerium were doped, the UV-Vis adsorption band wavelength showed an obvious shift toward the visible range （〈526 nm）. As the atomic ratio of Ce/Ti increased to 1.0, the absorbance edge wavelength increased to 481 nm. The absorbance edge wavelength decreased for higher cerium doping levels （Ce/Ti=2.0）. The particles size ranged from 122 to 255 nm with a domain at 168 nm （39.4%）. The degradation of ARB dye indicated that the photocatalytic activities of boron- and cerium-codoped TiO2 were much higher than those of P25 （a standard TiO2 powder）. The activities increased as the boron doping increased, whereas decreased when the Ce/Ti atomic ratio was greater than 0.5. The optimum atomic ratio of B/Ti and Ce/Ti was 1.6 and 0.5, respectively.展开更多
文摘目的研究臭氧氧化技术处理酸性红B染料废水的效果,并探讨O3投加量、废水的初始pH值、H2O2和O3物质的量比对臭氧氧化处理酸性红B染料废水效果的影响.方法依据臭氧高级氧化的机理,在实验室反应器中通过实验考察在臭氧氧化处理酸性红B染料废水过程中,控制不同的O3投加量、废水的初始pH值、H2O2和O3物质的量比对酸性红B染料废水的色度和COD去除率的影响.结果在pH=7的条件下,单一臭氧氧化30 m in时,废水的色度和COD去除率分别为99.5%和37.9%;而废水的初始pH值控制在11左右时,COD去除率有较大提高.O3/H2O2氧化工艺,适宜的H2O2和O3物质的量比为0.6,氧化处理30 m in废水的COD去除率可达53.5%.结论O3高级氧化能够有效降解酸性红B染料废水,在臭氧反应体系中投加H2O2可以明显提高降解速率,缩短处理时间,降低O3耗量.
基金Project supported by the National Natural Science Foundation of China (No. 20277010)
文摘Boron- and cerium-codoped TiO2 photocatalysts were synthesized using modified sol-gel reaction process and characterized by X- ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, particle size distribution （PSD）, diffuse reflectance spectra （DRS）, and Brunauer-Emmett-Teller （BET）. The photocatalytic activities were evaluated by monitoring the degradation of dye Acid Red B （ARB）. The results showed that the prepared photocatalysts were mixed oxides mainly consisting of titania, ceria, and boron oxide. The structure of TiO2 could be transformed from amorphous to anatase and then to rutile by increasing calcination temperature; the transformation being accompanied by the growth of particle size without any obvious change in phase structure of CeO2. The XPS of B1.6Ce1.0-TiO2 prepared at 500℃ showed that a few boron atoms were incorporated into titania and ceria lattice, whereas others existed as B2O3. Cerium ions existed in two states, Ce^3＋ and Ce^4＋, and the atomic ratio of Ce^3＋/Ce^4＋ was 1.86. When boron and cerium were doped, the UV-Vis adsorption band wavelength showed an obvious shift toward the visible range （〈526 nm）. As the atomic ratio of Ce/Ti increased to 1.0, the absorbance edge wavelength increased to 481 nm. The absorbance edge wavelength decreased for higher cerium doping levels （Ce/Ti=2.0）. The particles size ranged from 122 to 255 nm with a domain at 168 nm （39.4%）. The degradation of ARB dye indicated that the photocatalytic activities of boron- and cerium-codoped TiO2 were much higher than those of P25 （a standard TiO2 powder）. The activities increased as the boron doping increased, whereas decreased when the Ce/Ti atomic ratio was greater than 0.5. The optimum atomic ratio of B/Ti and Ce/Ti was 1.6 and 0.5, respectively.
