The nanometer and ordinary anatase titanium dioxide(TiO_2) powders were adopted as the sonocatalysts for the degradation of methyl orange used as a model compound for the first time. It was found that the sonocatalyti...The nanometer and ordinary anatase titanium dioxide(TiO_2) powders were adopted as the sonocatalysts for the degradation of methyl orange used as a model compound for the first time. It was found that the sonocatalytic degradation effect of methyl orange in the presence of TiO_2 powder were much better than that without TiO_2, but the sonocatalytic activity of the nanometer anatase TiO_2 particle was obviously higher than that of ordinary anatase TiO_2 particle. Although there are many factors influencing sonocatalytic degradation of methyl orange, the experimental results showed that the best degradation ratio of methyl orange could be obtained when the experimental conditions were: initial concentration 15 mg/L, nanometer anatase TiO_2 adding amount 750 mg/L, ultrasonic frequency 40 kHz, output power 50 W, pH = 3.0 and temperature 40℃ within 150 min. In addition, the catalytic activity of reused nanometer anatase TiO_2 catalyst was also studied and found to decline gradually comparing with initial nanometer anatase TiO_2 catalyst. All experiments indicated that the method of the sonocatalytic degradation of organic pollutants in the presence of TiO_2 powder was an advisable choice for non- or low-transparent organic wastewaters.展开更多
The mixed crystal nanometer TiO2 sonocatalyst was prepared by ultrasonic irradiation in hydrogen peroxide solution. The sonocatalytic activities were validated through the degradation of acid red B solution by ultraso...The mixed crystal nanometer TiO2 sonocatalyst was prepared by ultrasonic irradiation in hydrogen peroxide solution. The sonocatalytic activities were validated through the degradation of acid red B solution by ultrasonic irradiation in the presence of the title TiO2 catalyst. The results show that the sonocatalytic activity of the title TiO2 catalyst is obviously higher than that of original rutile and anatase nanometer TiO2 catalysts. The degradation ratio of acid red B in the presence of the title TiO2 catalyst surpasses 75%, while the degradation ratios are only 54.62% and 35.24% for rutile and anatase nanometer TiO2 catalysts, respectively.展开更多
LuFeO3 crystallites of different sizes and morphologies were synthesized via a hydrothermal route. The sonocatalytic properties of the as-synthesized samples were investigated by degrading various organic dyes, includ...LuFeO3 crystallites of different sizes and morphologies were synthesized via a hydrothermal route. The sonocatalytic properties of the as-synthesized samples were investigated by degrading various organic dyes, including acid orange 7 （AOT）, rhodamine B （RhB）, methyl orange （MO）, and methylene blue （MB）, under ultrasonic irradiation, revealing that they exhibit excellent sonocatalytic activity toward the degradation of these dyes. Particularly, the synthesized bar-like particles with lengths of-3 μm and widths of-1μm have the highest sonocatalytic activity, and the degradation percentage of AO7 reaches 89% after 30 min of sonocatalysis. The effects of inorganic anions such as CI-, NO3-, SO42-, PO43-, and HCO3- on the sonocatalysis efficiency were investigated. Hydroxyl radicals （·OH） detected by fiuorimetry using terephthalic acid as a probe molecule were found to be produced over the ultrasonic-irradiated LuFeO3 particles. The addition of ethanol, which acts as a· OH scavenger, leads to quenching of ＂OH radicals and a simultaneous decrease in the dye degrada- tion. This suggests that ＂OH is the dominant active species responsible for the dye degradation.展开更多
Bi2O2CO3是一种Bi类半导体催化剂,文章研究了它的超声催化性能。首先,采用水热法制备了微球型的Bi2O2CO3,利用X射线衍射(X-ray Diffraction,XRD)、扫描电子显微镜(Scanning Electron Microscope,SEM)、紫外-可见漫反射光谱对样品的晶体...Bi2O2CO3是一种Bi类半导体催化剂,文章研究了它的超声催化性能。首先,采用水热法制备了微球型的Bi2O2CO3,利用X射线衍射(X-ray Diffraction,XRD)、扫描电子显微镜(Scanning Electron Microscope,SEM)、紫外-可见漫反射光谱对样品的晶体结构、微观形貌、光学特性进行了表征。然后,以罗丹明B(RhB)作为模型污染物,通过研究超声催化降解罗丹明B来评测Bi2O2CO3的超声催化性能。研究了催化剂的浓度(Ccatalytic)、初始罗丹明B染料的浓度(CRhB)和超声功率(P)等实验因素对超声催化降解效率的影响。得出在Ccatalytic=3g·L^-1,CRhB=10mg·L^-1和P=400W条件下降解罗丹明B的效率最高,其最高降解效率可以达到91.7%。展开更多
The present study addressed the properties affecting the activity of a new heterogeneous catalyst Fe/Ti-NaY in the ultrasonic irradiated for decolorization of amaranth dye in aqueous solution. The catalyst was prepare...The present study addressed the properties affecting the activity of a new heterogeneous catalyst Fe/Ti-NaY in the ultrasonic irradiated for decolorization of amaranth dye in aqueous solution. The catalyst was prepared by the ion exchange and impregnation method. Different characterization techniques, i.e. XRD, AFM, TEM and SEM/EDAX were done to characterize the properties of the fresh and used catalyst. This catalyst was able to keep its stability and high activity without any noticeable reduction in the decolorization efficiency of amaranth after three cycles of reaction. The X-ray diffraction proved the high stability and the crystallinity for the reuse catalyst. The COD removal for the fresh and used catalyst with and without calcination was 57%, 36% and 20% respectively. The hydrophilic properties of the heterogeneous catalyst increased slightly due to the loading of Ti and Fe ions.展开更多
A series of graphene-TiO2 composites was fabricated from graphene oxide and titanium n-butoxide(TNB) by an ultrasonic-assisted method.The structure and composition of the nanocomposites were characterized by Raman spe...A series of graphene-TiO2 composites was fabricated from graphene oxide and titanium n-butoxide(TNB) by an ultrasonic-assisted method.The structure and composition of the nanocomposites were characterized by Raman spectroscopy,BET surface area measurements,X-ray diffraction,transmission electron microscopy,and ultraviolet-visible absorption spectroscopy.The average size of the TiO2 nanoparticles on the graphene nanosheets was controlled at around 10-15 nm without using surfactant,which is attributed to the pyrolysis and condensation of dissolved TNB into TiO2 by ultrasonic irradiation.The catalytic activity of the composites under ultrasonic irradiation was determined using a rhodamine B(RhB) solution.The graphene-TiO2 composites possessed a high specific surface area,which increased the decolorization rate for RhB solution.This is because the graphene and TiO2 nanoparticles in the composites interact strongly,which enhances the photoelectric conversion of TiO2 by reducing the recombination of photogenerated electron-hole pairs.展开更多
基金Foundation item: The National Natural Science Foundation of China(No. 20371023)
文摘The nanometer and ordinary anatase titanium dioxide(TiO_2) powders were adopted as the sonocatalysts for the degradation of methyl orange used as a model compound for the first time. It was found that the sonocatalytic degradation effect of methyl orange in the presence of TiO_2 powder were much better than that without TiO_2, but the sonocatalytic activity of the nanometer anatase TiO_2 particle was obviously higher than that of ordinary anatase TiO_2 particle. Although there are many factors influencing sonocatalytic degradation of methyl orange, the experimental results showed that the best degradation ratio of methyl orange could be obtained when the experimental conditions were: initial concentration 15 mg/L, nanometer anatase TiO_2 adding amount 750 mg/L, ultrasonic frequency 40 kHz, output power 50 W, pH = 3.0 and temperature 40℃ within 150 min. In addition, the catalytic activity of reused nanometer anatase TiO_2 catalyst was also studied and found to decline gradually comparing with initial nanometer anatase TiO_2 catalyst. All experiments indicated that the method of the sonocatalytic degradation of organic pollutants in the presence of TiO_2 powder was an advisable choice for non- or low-transparent organic wastewaters.
文摘The mixed crystal nanometer TiO2 sonocatalyst was prepared by ultrasonic irradiation in hydrogen peroxide solution. The sonocatalytic activities were validated through the degradation of acid red B solution by ultrasonic irradiation in the presence of the title TiO2 catalyst. The results show that the sonocatalytic activity of the title TiO2 catalyst is obviously higher than that of original rutile and anatase nanometer TiO2 catalysts. The degradation ratio of acid red B in the presence of the title TiO2 catalyst surpasses 75%, while the degradation ratios are only 54.62% and 35.24% for rutile and anatase nanometer TiO2 catalysts, respectively.
基金supported by the National Natural Science Foundation of China(51262018)the Fundamental Research Funds for Universities of Gansu Province(056003)the Hongliu Outstanding Talents Foundation of Lanzhou University of Technology(J201205)~~
文摘LuFeO3 crystallites of different sizes and morphologies were synthesized via a hydrothermal route. The sonocatalytic properties of the as-synthesized samples were investigated by degrading various organic dyes, including acid orange 7 （AOT）, rhodamine B （RhB）, methyl orange （MO）, and methylene blue （MB）, under ultrasonic irradiation, revealing that they exhibit excellent sonocatalytic activity toward the degradation of these dyes. Particularly, the synthesized bar-like particles with lengths of-3 μm and widths of-1μm have the highest sonocatalytic activity, and the degradation percentage of AO7 reaches 89% after 30 min of sonocatalysis. The effects of inorganic anions such as CI-, NO3-, SO42-, PO43-, and HCO3- on the sonocatalysis efficiency were investigated. Hydroxyl radicals （·OH） detected by fiuorimetry using terephthalic acid as a probe molecule were found to be produced over the ultrasonic-irradiated LuFeO3 particles. The addition of ethanol, which acts as a· OH scavenger, leads to quenching of ＂OH radicals and a simultaneous decrease in the dye degrada- tion. This suggests that ＂OH is the dominant active species responsible for the dye degradation.
文摘Bi2O2CO3是一种Bi类半导体催化剂,文章研究了它的超声催化性能。首先,采用水热法制备了微球型的Bi2O2CO3,利用X射线衍射(X-ray Diffraction,XRD)、扫描电子显微镜(Scanning Electron Microscope,SEM)、紫外-可见漫反射光谱对样品的晶体结构、微观形貌、光学特性进行了表征。然后,以罗丹明B(RhB)作为模型污染物,通过研究超声催化降解罗丹明B来评测Bi2O2CO3的超声催化性能。研究了催化剂的浓度(Ccatalytic)、初始罗丹明B染料的浓度(CRhB)和超声功率(P)等实验因素对超声催化降解效率的影响。得出在Ccatalytic=3g·L^-1,CRhB=10mg·L^-1和P=400W条件下降解罗丹明B的效率最高,其最高降解效率可以达到91.7%。
文摘The present study addressed the properties affecting the activity of a new heterogeneous catalyst Fe/Ti-NaY in the ultrasonic irradiated for decolorization of amaranth dye in aqueous solution. The catalyst was prepared by the ion exchange and impregnation method. Different characterization techniques, i.e. XRD, AFM, TEM and SEM/EDAX were done to characterize the properties of the fresh and used catalyst. This catalyst was able to keep its stability and high activity without any noticeable reduction in the decolorization efficiency of amaranth after three cycles of reaction. The X-ray diffraction proved the high stability and the crystallinity for the reuse catalyst. The COD removal for the fresh and used catalyst with and without calcination was 57%, 36% and 20% respectively. The hydrophilic properties of the heterogeneous catalyst increased slightly due to the loading of Ti and Fe ions.
文摘A series of graphene-TiO2 composites was fabricated from graphene oxide and titanium n-butoxide(TNB) by an ultrasonic-assisted method.The structure and composition of the nanocomposites were characterized by Raman spectroscopy,BET surface area measurements,X-ray diffraction,transmission electron microscopy,and ultraviolet-visible absorption spectroscopy.The average size of the TiO2 nanoparticles on the graphene nanosheets was controlled at around 10-15 nm without using surfactant,which is attributed to the pyrolysis and condensation of dissolved TNB into TiO2 by ultrasonic irradiation.The catalytic activity of the composites under ultrasonic irradiation was determined using a rhodamine B(RhB) solution.The graphene-TiO2 composites possessed a high specific surface area,which increased the decolorization rate for RhB solution.This is because the graphene and TiO2 nanoparticles in the composites interact strongly,which enhances the photoelectric conversion of TiO2 by reducing the recombination of photogenerated electron-hole pairs.
