The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
Xiangdong Zhang - One of the best experts on this subject based on the ideXlab platform.
-
sol gel preparation of fe doped mixed crystal tio2 powder and its photocatalytic activity for degradation of azo Fuchsine under visible light irradiation
Russian Journal of Inorganic Chemistry, 2010Co-Authors: Jun Wang, Zhe Jiang, Liquan Zhang, Yingpeng Xie, Zhiqiang Xing, Xiangdong ZhangAbstract:In this work, the Fe-doped mixed crystal TiO2 photocatalyst which can utilize visible light was prepared by sol-gel and heat-treated methods. During heat-treatment, the phase transformation of Fe-doped TiO2 powder occurs and the process is characterized by XRD and TG-DTA technologies. Otherwise, the sizes and shapes of Fe-doped and undoped TiO2 powders were also compared using TEM images. The azo Fuchsine in aqueous solutions, as a model compound, was treated under visible light irradiation using Fe-doped mixed crystal TiO2 powders as photocatalyst. The results showed that, under visible light irradiation, the (0.25%) Fe-doped mixed crystal TiO2 powder heat-treated at 600°C for 3.0 h behaved very high photocatalytic activities for degradation of azo Fuchsine. The remarkable improvement of the photocatalytic activity of TiO2 powder was elucidated through the cooperative effects of iron doping and phase transformation. The iron doping can restrain the recombination of photogenerated electron-hole pairs and the phase transformation can enhance the absorption of visible light. Furthermore, other influence factors such as azo Fuchsine concentration, solution acidity, Fe3+ ion content and irradiation time were also studied. Thus, this method is applicable for the treatment of wastewater.
-
sonocatalytic degradation of azo Fuchsine in the presence of the co doped and cr doped mixed crystal tio2 powders and comparison of their sonocatalytic activities
Journal of Hazardous Materials, 2009Co-Authors: Jun Wang, Zhaohong Zhang, Liquan Zhang, Yingqiao Deng, Bin Liu, Xiangdong ZhangAbstract:In order to degrade some pollutants effectively under ultrasonic irradiation, the Co-doped and Cr-doped mixed crystal TiO2 powders, with high sonocatalytic activity, were prepared as sonocatalyst. The Co-doped and Cr-doped mixed crystal TiO2 powders as sonocatalyst were prepared through sol–gel and heat-treated methods from tetrabutylorthotitanate, and then were characterized by XRD and TG–DTA technologies. In order to compare and evaluate the sonocatalytic activity of the Co-doped and Cr-doped mixed crystal TiO2 powders, the low power ultrasound was as an irradiation source and the azo Fuchsine was chosen as a model compound to be degraded. The degradation process was investigated by UV–vis, TOC, ion chromatogram and HPLC techniques. The results indicated that the sonocatalytic activity of Cr-doped mixed crystal TiO2 powder was higher than that of Co-doped and undoped mixed crystal TiO2 powder during the sonocatalytic degradation of the azo Fuchsine in aqueous solution. These results may be of great significance for driving sonocatalytic method to treat non- or low-transparent industrial wastewaters.
-
preparation of fe doped mixed crystal tio2 catalyst and investigation of its sonocatalytic activity during degradation of azo Fuchsine under ultrasonic irradiation
Journal of Colloid and Interface Science, 2008Co-Authors: Jun Wang, Zhaohong Zhang, Wei Sun, Zhe Jiang, Xiaofang Wang, Xiangdong ZhangAbstract:Abstract In this work, Fe-doped mixed crystal TiO 2 powder as sonocatalyst was prepared by the sol–gel method and heat treatment, and a novel method combined with ultrasonic irradiation was propounded to degrade the organic polluted water. First, the Fe-doped mixed crystal TiO 2 powder was characterized by TG–DTA, XRD, and TEM techniques. Ultrasound was used as the irradiation source and the azo Fuchsine was chose as the model compound. Then a series of degradation experiments was carried out in the presence of Fe-doped mixed crystal TiO 2 powder. Also, the degradation process and some influencing factors, such as irradiation time, doping Fe 3+ ion content, added amount of catalyst, and initial concentration of azo Fuchsine solution, on the degradation were investigated by UV–vis spectra, ion chromatography, and HPLC. Through the degradation of azo Fuchsine, it was found that the combination of ultrasonic irradiation and Fe-doped mixed crystal TiO 2 powder can completely degrade the azo Fuchsine in aqueous solution. Because of the good degradation efficiency, this method may be an advisable choice for the treatments of non- or low-transparent wastewaters in the future.
-
the investigation on ultrasonic degradation of acid Fuchsine in the presence of ordinary and nanometer rutile tio2 and the comparison of their sonocatalytic activities
Dyes and Pigments, 2007Co-Authors: Jun Wang, Zhijun Pan, Zhaohong Zhang, Xiangdong Zhang, Yuefeng Jiang, Fuyu Wen, Peng ZhangAbstract:Abstract The ordinary and nanometer rutile titanium dioxide (TiO 2 ) powders were used as sonocatalysts for the degradation of acid Fuchsine. A variety of factors affecting sonocatalytic degradation in the presence of ordinary and nanometer rutile TiO 2 were studied. The experimental results indicated that the degradation ratios of acid Fuchsine in the presence of ordinary and nanometer rutile TiO 2 powders were much better than one without any TiO 2 under onefold ultrasonic irradiation. For ordinary and nanometer rutile TiO 2 powders, the sonocatalytic ability of ordinary rutile TiO 2 powder was more apparent than that of the nanometer rutile TiO 2 powder. The best degradation ratio of acid Fuchsine can be obtained at the ultrasonic irradiation of 40 kHz frequency and 50 W power, 500 mg/L TiO 2 adding amount, pH = 3.0 and 20 mg/L acid Fuchsine as the initial concentration. The experimental results indicated that the method of sonocatalytic degradation of organic pollutants in the presence of TiO 2 powder was an advisable choice for treating organic wastewaters for non- or low-transparent and fuscous dye wastewater.
-
investigation on degradation of azo Fuchsine using visible light in the presence of heat treated anatase tio2 powder
Dyes and Pigments, 2007Co-Authors: Jun Wang, Zhaohong Zhang, Xiangdong Zhang, Yuefeng Jiang, Gang Zhao, Guan Zhang, Peng ZhangAbstract:Abstract The phase transformation of TiO 2 powder from anatase phase to rutile phase was attempted by heat-treatment, and a new TiO 2 photocatalyst was obtained which could be excitated by visible light. The heat-treated TiO 2 powder at different transition stage was characterized by XRD, FT-IR and TEM methods. The test of photocatalytic activities of the heat-treated TiO 2 powders were carried out through the photocatalytic degradation of azo Fuchsine dye in aqueous solution under the irradiation of visible light. The results indicate that the TiO 2 photocatalyst heat-treated at 400 °C within 60 min shows the highest photocatalytic activity which can effectively degrade the azo Fuchsine under the irradiation of visible light. The remarkable improvement of photocatalytic activity of heat-treated TiO 2 powders at 400 °C was mainly illustrated by the special interphase formed between rutile and anatase phases which not only restrains the recombination of photogenerated electron–hole pairs, but also reduces the adsorbability of anatase TiO 2 powders at a certain extent. The degradation ratio of azo Fuchsine in the presence of the heat-treated TiO 2 catalyst surpassed 84.36% at 3 h visible light irradiation, while the degradation ratios are only 44.2% and 64.84% for ordinary rutile and anatase TiO 2 catalysts, respectively, under the same experimental conditions. The total degradation process of azo Fuchsine has been monitored by UV–vis spectra and ion chromatography. At last, the azo Fuchsine molecules in aqueous solution are completely degraded and become some simple inorganic ions such as NO 3 − and SO 4 2− , etc. In this paper, the research on photocatalytic degradation kinetics was also performed and proved to be a first-order reaction.
Jun Wang - One of the best experts on this subject based on the ideXlab platform.
-
sol gel preparation of fe doped mixed crystal tio2 powder and its photocatalytic activity for degradation of azo Fuchsine under visible light irradiation
Russian Journal of Inorganic Chemistry, 2010Co-Authors: Jun Wang, Zhe Jiang, Liquan Zhang, Yingpeng Xie, Zhiqiang Xing, Xiangdong ZhangAbstract:In this work, the Fe-doped mixed crystal TiO2 photocatalyst which can utilize visible light was prepared by sol-gel and heat-treated methods. During heat-treatment, the phase transformation of Fe-doped TiO2 powder occurs and the process is characterized by XRD and TG-DTA technologies. Otherwise, the sizes and shapes of Fe-doped and undoped TiO2 powders were also compared using TEM images. The azo Fuchsine in aqueous solutions, as a model compound, was treated under visible light irradiation using Fe-doped mixed crystal TiO2 powders as photocatalyst. The results showed that, under visible light irradiation, the (0.25%) Fe-doped mixed crystal TiO2 powder heat-treated at 600°C for 3.0 h behaved very high photocatalytic activities for degradation of azo Fuchsine. The remarkable improvement of the photocatalytic activity of TiO2 powder was elucidated through the cooperative effects of iron doping and phase transformation. The iron doping can restrain the recombination of photogenerated electron-hole pairs and the phase transformation can enhance the absorption of visible light. Furthermore, other influence factors such as azo Fuchsine concentration, solution acidity, Fe3+ ion content and irradiation time were also studied. Thus, this method is applicable for the treatment of wastewater.
-
sonocatalytic degradation of azo Fuchsine in the presence of the co doped and cr doped mixed crystal tio2 powders and comparison of their sonocatalytic activities
Journal of Hazardous Materials, 2009Co-Authors: Jun Wang, Zhaohong Zhang, Liquan Zhang, Yingqiao Deng, Bin Liu, Xiangdong ZhangAbstract:In order to degrade some pollutants effectively under ultrasonic irradiation, the Co-doped and Cr-doped mixed crystal TiO2 powders, with high sonocatalytic activity, were prepared as sonocatalyst. The Co-doped and Cr-doped mixed crystal TiO2 powders as sonocatalyst were prepared through sol–gel and heat-treated methods from tetrabutylorthotitanate, and then were characterized by XRD and TG–DTA technologies. In order to compare and evaluate the sonocatalytic activity of the Co-doped and Cr-doped mixed crystal TiO2 powders, the low power ultrasound was as an irradiation source and the azo Fuchsine was chosen as a model compound to be degraded. The degradation process was investigated by UV–vis, TOC, ion chromatogram and HPLC techniques. The results indicated that the sonocatalytic activity of Cr-doped mixed crystal TiO2 powder was higher than that of Co-doped and undoped mixed crystal TiO2 powder during the sonocatalytic degradation of the azo Fuchsine in aqueous solution. These results may be of great significance for driving sonocatalytic method to treat non- or low-transparent industrial wastewaters.
-
preparation of fe doped mixed crystal tio2 catalyst and investigation of its sonocatalytic activity during degradation of azo Fuchsine under ultrasonic irradiation
Journal of Colloid and Interface Science, 2008Co-Authors: Jun Wang, Zhaohong Zhang, Wei Sun, Zhe Jiang, Xiaofang Wang, Xiangdong ZhangAbstract:Abstract In this work, Fe-doped mixed crystal TiO 2 powder as sonocatalyst was prepared by the sol–gel method and heat treatment, and a novel method combined with ultrasonic irradiation was propounded to degrade the organic polluted water. First, the Fe-doped mixed crystal TiO 2 powder was characterized by TG–DTA, XRD, and TEM techniques. Ultrasound was used as the irradiation source and the azo Fuchsine was chose as the model compound. Then a series of degradation experiments was carried out in the presence of Fe-doped mixed crystal TiO 2 powder. Also, the degradation process and some influencing factors, such as irradiation time, doping Fe 3+ ion content, added amount of catalyst, and initial concentration of azo Fuchsine solution, on the degradation were investigated by UV–vis spectra, ion chromatography, and HPLC. Through the degradation of azo Fuchsine, it was found that the combination of ultrasonic irradiation and Fe-doped mixed crystal TiO 2 powder can completely degrade the azo Fuchsine in aqueous solution. Because of the good degradation efficiency, this method may be an advisable choice for the treatments of non- or low-transparent wastewaters in the future.
-
the investigation on ultrasonic degradation of acid Fuchsine in the presence of ordinary and nanometer rutile tio2 and the comparison of their sonocatalytic activities
Dyes and Pigments, 2007Co-Authors: Jun Wang, Zhijun Pan, Zhaohong Zhang, Xiangdong Zhang, Yuefeng Jiang, Fuyu Wen, Peng ZhangAbstract:Abstract The ordinary and nanometer rutile titanium dioxide (TiO 2 ) powders were used as sonocatalysts for the degradation of acid Fuchsine. A variety of factors affecting sonocatalytic degradation in the presence of ordinary and nanometer rutile TiO 2 were studied. The experimental results indicated that the degradation ratios of acid Fuchsine in the presence of ordinary and nanometer rutile TiO 2 powders were much better than one without any TiO 2 under onefold ultrasonic irradiation. For ordinary and nanometer rutile TiO 2 powders, the sonocatalytic ability of ordinary rutile TiO 2 powder was more apparent than that of the nanometer rutile TiO 2 powder. The best degradation ratio of acid Fuchsine can be obtained at the ultrasonic irradiation of 40 kHz frequency and 50 W power, 500 mg/L TiO 2 adding amount, pH = 3.0 and 20 mg/L acid Fuchsine as the initial concentration. The experimental results indicated that the method of sonocatalytic degradation of organic pollutants in the presence of TiO 2 powder was an advisable choice for treating organic wastewaters for non- or low-transparent and fuscous dye wastewater.
-
investigation on degradation of azo Fuchsine using visible light in the presence of heat treated anatase tio2 powder
Dyes and Pigments, 2007Co-Authors: Jun Wang, Zhaohong Zhang, Xiangdong Zhang, Yuefeng Jiang, Gang Zhao, Guan Zhang, Peng ZhangAbstract:Abstract The phase transformation of TiO 2 powder from anatase phase to rutile phase was attempted by heat-treatment, and a new TiO 2 photocatalyst was obtained which could be excitated by visible light. The heat-treated TiO 2 powder at different transition stage was characterized by XRD, FT-IR and TEM methods. The test of photocatalytic activities of the heat-treated TiO 2 powders were carried out through the photocatalytic degradation of azo Fuchsine dye in aqueous solution under the irradiation of visible light. The results indicate that the TiO 2 photocatalyst heat-treated at 400 °C within 60 min shows the highest photocatalytic activity which can effectively degrade the azo Fuchsine under the irradiation of visible light. The remarkable improvement of photocatalytic activity of heat-treated TiO 2 powders at 400 °C was mainly illustrated by the special interphase formed between rutile and anatase phases which not only restrains the recombination of photogenerated electron–hole pairs, but also reduces the adsorbability of anatase TiO 2 powders at a certain extent. The degradation ratio of azo Fuchsine in the presence of the heat-treated TiO 2 catalyst surpassed 84.36% at 3 h visible light irradiation, while the degradation ratios are only 44.2% and 64.84% for ordinary rutile and anatase TiO 2 catalysts, respectively, under the same experimental conditions. The total degradation process of azo Fuchsine has been monitored by UV–vis spectra and ion chromatography. At last, the azo Fuchsine molecules in aqueous solution are completely degraded and become some simple inorganic ions such as NO 3 − and SO 4 2− , etc. In this paper, the research on photocatalytic degradation kinetics was also performed and proved to be a first-order reaction.
Zhaohong Zhang - One of the best experts on this subject based on the ideXlab platform.
-
sonocatalytic degradation of azo Fuchsine in the presence of the co doped and cr doped mixed crystal tio2 powders and comparison of their sonocatalytic activities
Journal of Hazardous Materials, 2009Co-Authors: Jun Wang, Zhaohong Zhang, Liquan Zhang, Yingqiao Deng, Bin Liu, Xiangdong ZhangAbstract:In order to degrade some pollutants effectively under ultrasonic irradiation, the Co-doped and Cr-doped mixed crystal TiO2 powders, with high sonocatalytic activity, were prepared as sonocatalyst. The Co-doped and Cr-doped mixed crystal TiO2 powders as sonocatalyst were prepared through sol–gel and heat-treated methods from tetrabutylorthotitanate, and then were characterized by XRD and TG–DTA technologies. In order to compare and evaluate the sonocatalytic activity of the Co-doped and Cr-doped mixed crystal TiO2 powders, the low power ultrasound was as an irradiation source and the azo Fuchsine was chosen as a model compound to be degraded. The degradation process was investigated by UV–vis, TOC, ion chromatogram and HPLC techniques. The results indicated that the sonocatalytic activity of Cr-doped mixed crystal TiO2 powder was higher than that of Co-doped and undoped mixed crystal TiO2 powder during the sonocatalytic degradation of the azo Fuchsine in aqueous solution. These results may be of great significance for driving sonocatalytic method to treat non- or low-transparent industrial wastewaters.
-
preparation of fe doped mixed crystal tio2 catalyst and investigation of its sonocatalytic activity during degradation of azo Fuchsine under ultrasonic irradiation
Journal of Colloid and Interface Science, 2008Co-Authors: Jun Wang, Zhaohong Zhang, Wei Sun, Zhe Jiang, Xiaofang Wang, Xiangdong ZhangAbstract:Abstract In this work, Fe-doped mixed crystal TiO 2 powder as sonocatalyst was prepared by the sol–gel method and heat treatment, and a novel method combined with ultrasonic irradiation was propounded to degrade the organic polluted water. First, the Fe-doped mixed crystal TiO 2 powder was characterized by TG–DTA, XRD, and TEM techniques. Ultrasound was used as the irradiation source and the azo Fuchsine was chose as the model compound. Then a series of degradation experiments was carried out in the presence of Fe-doped mixed crystal TiO 2 powder. Also, the degradation process and some influencing factors, such as irradiation time, doping Fe 3+ ion content, added amount of catalyst, and initial concentration of azo Fuchsine solution, on the degradation were investigated by UV–vis spectra, ion chromatography, and HPLC. Through the degradation of azo Fuchsine, it was found that the combination of ultrasonic irradiation and Fe-doped mixed crystal TiO 2 powder can completely degrade the azo Fuchsine in aqueous solution. Because of the good degradation efficiency, this method may be an advisable choice for the treatments of non- or low-transparent wastewaters in the future.
-
the investigation on ultrasonic degradation of acid Fuchsine in the presence of ordinary and nanometer rutile tio2 and the comparison of their sonocatalytic activities
Dyes and Pigments, 2007Co-Authors: Jun Wang, Zhijun Pan, Zhaohong Zhang, Xiangdong Zhang, Yuefeng Jiang, Fuyu Wen, Peng ZhangAbstract:Abstract The ordinary and nanometer rutile titanium dioxide (TiO 2 ) powders were used as sonocatalysts for the degradation of acid Fuchsine. A variety of factors affecting sonocatalytic degradation in the presence of ordinary and nanometer rutile TiO 2 were studied. The experimental results indicated that the degradation ratios of acid Fuchsine in the presence of ordinary and nanometer rutile TiO 2 powders were much better than one without any TiO 2 under onefold ultrasonic irradiation. For ordinary and nanometer rutile TiO 2 powders, the sonocatalytic ability of ordinary rutile TiO 2 powder was more apparent than that of the nanometer rutile TiO 2 powder. The best degradation ratio of acid Fuchsine can be obtained at the ultrasonic irradiation of 40 kHz frequency and 50 W power, 500 mg/L TiO 2 adding amount, pH = 3.0 and 20 mg/L acid Fuchsine as the initial concentration. The experimental results indicated that the method of sonocatalytic degradation of organic pollutants in the presence of TiO 2 powder was an advisable choice for treating organic wastewaters for non- or low-transparent and fuscous dye wastewater.
-
investigation on degradation of azo Fuchsine using visible light in the presence of heat treated anatase tio2 powder
Dyes and Pigments, 2007Co-Authors: Jun Wang, Zhaohong Zhang, Xiangdong Zhang, Yuefeng Jiang, Gang Zhao, Guan Zhang, Peng ZhangAbstract:Abstract The phase transformation of TiO 2 powder from anatase phase to rutile phase was attempted by heat-treatment, and a new TiO 2 photocatalyst was obtained which could be excitated by visible light. The heat-treated TiO 2 powder at different transition stage was characterized by XRD, FT-IR and TEM methods. The test of photocatalytic activities of the heat-treated TiO 2 powders were carried out through the photocatalytic degradation of azo Fuchsine dye in aqueous solution under the irradiation of visible light. The results indicate that the TiO 2 photocatalyst heat-treated at 400 °C within 60 min shows the highest photocatalytic activity which can effectively degrade the azo Fuchsine under the irradiation of visible light. The remarkable improvement of photocatalytic activity of heat-treated TiO 2 powders at 400 °C was mainly illustrated by the special interphase formed between rutile and anatase phases which not only restrains the recombination of photogenerated electron–hole pairs, but also reduces the adsorbability of anatase TiO 2 powders at a certain extent. The degradation ratio of azo Fuchsine in the presence of the heat-treated TiO 2 catalyst surpassed 84.36% at 3 h visible light irradiation, while the degradation ratios are only 44.2% and 64.84% for ordinary rutile and anatase TiO 2 catalysts, respectively, under the same experimental conditions. The total degradation process of azo Fuchsine has been monitored by UV–vis spectra and ion chromatography. At last, the azo Fuchsine molecules in aqueous solution are completely degraded and become some simple inorganic ions such as NO 3 − and SO 4 2− , etc. In this paper, the research on photocatalytic degradation kinetics was also performed and proved to be a first-order reaction.
-
investigation on degradation of dyestuff wastewater using visible light in the presence of a novel nano tio2 catalyst doped with upconversion luminescence agent
Journal of Photochemistry and Photobiology A-chemistry, 2006Co-Authors: J Wang, Zhijun Pan, Zhaohong Zhang, Xiangdong Zhang, Fuyu Wen, Peng Zhang, Pingli Kang, Jian Tong, Lei WangAbstract:Abstract A new upconversion luminescence agent, 40CdF 2 ·60BaF 2 ·1.0Er 2 O 3 , was synthesized and its fluorescent spectrum was determined. This upconversion luminescence agent can emit five upconversion fluorescent peaks shown in the fluorescent spectrum whose wavelengths are all below 387 nm under the excitation of 488 nm visible light. This upconversion luminescence agent was mixed into nano rutile TiO 2 powder by ultrasonic and boiling dispersion and then a novel doped nano TiO 2 photocatalyst utilizing visible light was firstly prepared. The doped nano TiO 2 powder was charactered by XRD and TEM and its photocatalytic activity was checked through the photocatalytic degradation reaction of azo Fuchsine as a model compound under the visible light irradiation emitted by 6 three basic color lamps. Otherwise, in order to compare the photocatalytic activities the same experiment was carried out for undoped TiO 2 powder. The degradation ratio of azo Fuchsine in the presence of doped nano TiO 2 powder reached 95% under visible light irradiation within 24 h, which was obviously higher than the corresponding degradation ratio of 21% in the presence of undoped nano rutile TiO 2 powder. It indicates that the upconversion luminescence agent prepared as dopant can effectively turn visible lights to ultraviolet lights that are absorbed by nano TiO 2 particles to produce the electron–cavity pairs. All the results show that the nano rutile TiO 2 powder doped with upconversion luminescence agent is a promising photocatalyst using sunlight for treating the industry dye wastewater in great force.
Peng Zhang - One of the best experts on this subject based on the ideXlab platform.
-
the investigation on ultrasonic degradation of acid Fuchsine in the presence of ordinary and nanometer rutile tio2 and the comparison of their sonocatalytic activities
Dyes and Pigments, 2007Co-Authors: Jun Wang, Zhijun Pan, Zhaohong Zhang, Xiangdong Zhang, Yuefeng Jiang, Fuyu Wen, Peng ZhangAbstract:Abstract The ordinary and nanometer rutile titanium dioxide (TiO 2 ) powders were used as sonocatalysts for the degradation of acid Fuchsine. A variety of factors affecting sonocatalytic degradation in the presence of ordinary and nanometer rutile TiO 2 were studied. The experimental results indicated that the degradation ratios of acid Fuchsine in the presence of ordinary and nanometer rutile TiO 2 powders were much better than one without any TiO 2 under onefold ultrasonic irradiation. For ordinary and nanometer rutile TiO 2 powders, the sonocatalytic ability of ordinary rutile TiO 2 powder was more apparent than that of the nanometer rutile TiO 2 powder. The best degradation ratio of acid Fuchsine can be obtained at the ultrasonic irradiation of 40 kHz frequency and 50 W power, 500 mg/L TiO 2 adding amount, pH = 3.0 and 20 mg/L acid Fuchsine as the initial concentration. The experimental results indicated that the method of sonocatalytic degradation of organic pollutants in the presence of TiO 2 powder was an advisable choice for treating organic wastewaters for non- or low-transparent and fuscous dye wastewater.
-
investigation on degradation of azo Fuchsine using visible light in the presence of heat treated anatase tio2 powder
Dyes and Pigments, 2007Co-Authors: Jun Wang, Zhaohong Zhang, Xiangdong Zhang, Yuefeng Jiang, Gang Zhao, Guan Zhang, Peng ZhangAbstract:Abstract The phase transformation of TiO 2 powder from anatase phase to rutile phase was attempted by heat-treatment, and a new TiO 2 photocatalyst was obtained which could be excitated by visible light. The heat-treated TiO 2 powder at different transition stage was characterized by XRD, FT-IR and TEM methods. The test of photocatalytic activities of the heat-treated TiO 2 powders were carried out through the photocatalytic degradation of azo Fuchsine dye in aqueous solution under the irradiation of visible light. The results indicate that the TiO 2 photocatalyst heat-treated at 400 °C within 60 min shows the highest photocatalytic activity which can effectively degrade the azo Fuchsine under the irradiation of visible light. The remarkable improvement of photocatalytic activity of heat-treated TiO 2 powders at 400 °C was mainly illustrated by the special interphase formed between rutile and anatase phases which not only restrains the recombination of photogenerated electron–hole pairs, but also reduces the adsorbability of anatase TiO 2 powders at a certain extent. The degradation ratio of azo Fuchsine in the presence of the heat-treated TiO 2 catalyst surpassed 84.36% at 3 h visible light irradiation, while the degradation ratios are only 44.2% and 64.84% for ordinary rutile and anatase TiO 2 catalysts, respectively, under the same experimental conditions. The total degradation process of azo Fuchsine has been monitored by UV–vis spectra and ion chromatography. At last, the azo Fuchsine molecules in aqueous solution are completely degraded and become some simple inorganic ions such as NO 3 − and SO 4 2− , etc. In this paper, the research on photocatalytic degradation kinetics was also performed and proved to be a first-order reaction.
-
investigation on degradation of dyestuff wastewater using visible light in the presence of a novel nano tio2 catalyst doped with upconversion luminescence agent
Journal of Photochemistry and Photobiology A-chemistry, 2006Co-Authors: J Wang, Zhijun Pan, Zhaohong Zhang, Xiangdong Zhang, Fuyu Wen, Peng Zhang, Pingli Kang, Jian Tong, Lei WangAbstract:Abstract A new upconversion luminescence agent, 40CdF 2 ·60BaF 2 ·1.0Er 2 O 3 , was synthesized and its fluorescent spectrum was determined. This upconversion luminescence agent can emit five upconversion fluorescent peaks shown in the fluorescent spectrum whose wavelengths are all below 387 nm under the excitation of 488 nm visible light. This upconversion luminescence agent was mixed into nano rutile TiO 2 powder by ultrasonic and boiling dispersion and then a novel doped nano TiO 2 photocatalyst utilizing visible light was firstly prepared. The doped nano TiO 2 powder was charactered by XRD and TEM and its photocatalytic activity was checked through the photocatalytic degradation reaction of azo Fuchsine as a model compound under the visible light irradiation emitted by 6 three basic color lamps. Otherwise, in order to compare the photocatalytic activities the same experiment was carried out for undoped TiO 2 powder. The degradation ratio of azo Fuchsine in the presence of doped nano TiO 2 powder reached 95% under visible light irradiation within 24 h, which was obviously higher than the corresponding degradation ratio of 21% in the presence of undoped nano rutile TiO 2 powder. It indicates that the upconversion luminescence agent prepared as dopant can effectively turn visible lights to ultraviolet lights that are absorbed by nano TiO 2 particles to produce the electron–cavity pairs. All the results show that the nano rutile TiO 2 powder doped with upconversion luminescence agent is a promising photocatalyst using sunlight for treating the industry dye wastewater in great force.
Qingyou Zhang - One of the best experts on this subject based on the ideXlab platform.
-
heavy metal ions and organic dyes removal from water by cellulose modified with maleic anhydride
Journal of Materials Science, 2012Co-Authors: Yanmei Zhou, Xiaoyi Hu, Qingyou ZhangAbstract:A novel type of adsorbent (CM) was synthesized by cellulose modified with maleic anhydride to remove heavy metal ions and organic dyes in this work. The synthesized adsorbent was characterized by FTIR, SEM, TGA and XRD. The degree of carboxyl group of CM was found to be 2.7 mmol g−1 by the titration method. The adsorption of Hg(II) ions as heavy metal ions while basic Fuchsine, methylene blue and crystal violet as organic dyes by CM was investigated. The influence of different experimental parameters such as pH, contact time, temperature on removal process was evaluated. The results indicated that the CM has a good adsorption capacity for Hg(II). The maximum adsorption capacity of Hg(II) was found to be 172.5 mg g−1, and the adsorption process was described by Freundlich isotherm model of adsorption well. The process of basic Fuchsine, methylene blue and crystal violet adsorbed by CM was also studied and the adsorption removal rate of those organic dyes was 88.10, 98.47 and 92.85 % under the optimum conditions, respectively. The adsorption process was depicted by the Langmuir isotherm model more correctly.
-
heavy metal ions and organic dyes removal from water by cellulose modified with maleic anhydride
Journal of Materials Science, 2012Co-Authors: Yanmei Zhou, Xiaoyi Hu, Qingyou ZhangAbstract:A novel type of adsorbent (CM) was synthesized by cellulose modified with maleic anhydride to remove heavy metal ions and organic dyes in this work. The synthesized adsorbent was characterized by FTIR, SEM, TGA and XRD. The degree of carboxyl group of CM was found to be 2.7 mmol g−1 by the titration method. The adsorption of Hg(II) ions as heavy metal ions while basic Fuchsine, methylene blue and crystal violet as organic dyes by CM was investigated. The influence of different experimental parameters such as pH, contact time, temperature on removal process was evaluated. The results indicated that the CM has a good adsorption capacity for Hg(II). The maximum adsorption capacity of Hg(II) was found to be 172.5 mg g−1, and the adsorption process was described by Freundlich isotherm model of adsorption well. The process of basic Fuchsine, methylene blue and crystal violet adsorbed by CM was also studied and the adsorption removal rate of those organic dyes was 88.10, 98.47 and 92.85 % under the optimum conditions, respectively. The adsorption process was depicted by the Langmuir isotherm model more correctly.
