High purity ammonium metavanadate(NH_(4)VO_(3))is the most vital chemical to produce V2O5,VO2,VN alloy,VFe alloy and VOSO4,which have some prospective applications for high strength steel,smart window,infrared detecto...High purity ammonium metavanadate(NH_(4)VO_(3))is the most vital chemical to produce V2O5,VO2,VN alloy,VFe alloy and VOSO4,which have some prospective applications for high strength steel,smart window,infrared detector and imaging,large scale energy storage system.NH_(4)VO_(3)is usually produced by spontaneous crystallization from the aqueous solution due to its sharp dependence of solubility on the temperature.However,hazardous chemicals in industrial effluent,include phosphorate,silicate and arsenate,causing severe damage to the environment.In this work,these impurities are selectively precipitated onto inorganic flocculants,while the vanadate dissolved in an aqueous solution keeps almost undisturbed.Therefore,high purity NH_(4)VO_(3)is produced by the crystallization from the purified solution.By screening various flocculants and precipitating parameters,polyaluminum sulfate with an optimal amount of 50 g/L,is demonstrated to selectively remove phosphorate,silicate and arsenate,corresponding to the removing efficiency of 93.39%,97.11%and 88.31%,respectively.NH_(4)VO_(3)from the purified solution holds a purity of 99.21%,in comparison with 98.33%in the product from the crude solution.This purifying technology cannot only produce NH_(4)VO_(3)with high added value,but also reduce the environmental pollution of waste liquid.展开更多
V2Os/TiO2 composite films were prepared on pure titanium substmtes via micro-arc oxidation （MAO） in electrolytes consisting of NaVO3. Their morphology and dements were characterized by scanning electron microscopy ...V2Os/TiO2 composite films were prepared on pure titanium substmtes via micro-arc oxidation （MAO） in electrolytes consisting of NaVO3. Their morphology and dements were characterized by scanning electron microscopy （SEM） and energy-dispersive X-ray （EDX） analysis. Phase composition and valence states of species in the films were characterized by X-ray diffraction （XRD） and X-ray photoelec- tron spectroscopy （XPS）. Ultraviolet-visible diffuse reflectance spectra （UV-Vis DRS） were also employed to evaluate the photophysical property of the films. The VEOs/TiO2 composite films show a sheet-like morphology. Not only V205 phase appears in the films when the NaVO3 concentration of the electrolyte is higher than 6,10 g/L and is loaded at the surface of anatase, but also V4＋ is incorporated into the crystal lattice of anatase. In comparison with pure TiO2 films the V2Os/TiO2 composite films exhibit significantly narrow band gap energy. The film prepared in an electrolyte consisting of NaVO3 with a concentration of 8.54 g/L exhibits the narrowest band gap energy, which is approximately 1.89 eV. The V2Os/TiO2 composite films also have the significantly enhanced visible light photocatalytic activity. The film prepared in an electrolyte consisting of NaVO3 with a concentration of 8.54 g/L exhibits the best photocatalytic activity and about 93% of rhodamine is degraded after 14 h visible light radiation.展开更多
The method is based on the oxidation of chlorpromazine with ammonium metavanadate in pH 2.4 solution, the absorbance of coloured compound was measured at 530 nm. Calibration graphs are linear over the concentration r...The method is based on the oxidation of chlorpromazine with ammonium metavanadate in pH 2.4 solution, the absorbance of coloured compound was measured at 530 nm. Calibration graphs are linear over the concentration range 0 to approximately 250 mu g/mL. The apparent molar absorptivity was 1.28 multiplied by 10**3 L center dot mol** minus **1 center dot cm** minus **1. The proposed method was applied to the determination of chlorpromazine tablets with satisfactory results. (Author abstract) 4 Refs.展开更多
基金support from the Natural Science Foundation of Hubei Province(2020BED011)XPS characterizations and ICP-OES were carried out in the Analytical and Testing Center in HUST.
文摘High purity ammonium metavanadate(NH_(4)VO_(3))is the most vital chemical to produce V2O5,VO2,VN alloy,VFe alloy and VOSO4,which have some prospective applications for high strength steel,smart window,infrared detector and imaging,large scale energy storage system.NH_(4)VO_(3)is usually produced by spontaneous crystallization from the aqueous solution due to its sharp dependence of solubility on the temperature.However,hazardous chemicals in industrial effluent,include phosphorate,silicate and arsenate,causing severe damage to the environment.In this work,these impurities are selectively precipitated onto inorganic flocculants,while the vanadate dissolved in an aqueous solution keeps almost undisturbed.Therefore,high purity NH_(4)VO_(3)is produced by the crystallization from the purified solution.By screening various flocculants and precipitating parameters,polyaluminum sulfate with an optimal amount of 50 g/L,is demonstrated to selectively remove phosphorate,silicate and arsenate,corresponding to the removing efficiency of 93.39%,97.11%and 88.31%,respectively.NH_(4)VO_(3)from the purified solution holds a purity of 99.21%,in comparison with 98.33%in the product from the crude solution.This purifying technology cannot only produce NH_(4)VO_(3)with high added value,but also reduce the environmental pollution of waste liquid.
基金the Open Research Fund of the National Defense Key Disciplines Laboratory of Light Alloy Processing Science and Technology in Nanchang Hangkong University(No.gf200901002)the Analytical and Testing Center of Huazhong University of Science and Technology
文摘V2Os/TiO2 composite films were prepared on pure titanium substmtes via micro-arc oxidation （MAO） in electrolytes consisting of NaVO3. Their morphology and dements were characterized by scanning electron microscopy （SEM） and energy-dispersive X-ray （EDX） analysis. Phase composition and valence states of species in the films were characterized by X-ray diffraction （XRD） and X-ray photoelec- tron spectroscopy （XPS）. Ultraviolet-visible diffuse reflectance spectra （UV-Vis DRS） were also employed to evaluate the photophysical property of the films. The VEOs/TiO2 composite films show a sheet-like morphology. Not only V205 phase appears in the films when the NaVO3 concentration of the electrolyte is higher than 6,10 g/L and is loaded at the surface of anatase, but also V4＋ is incorporated into the crystal lattice of anatase. In comparison with pure TiO2 films the V2Os/TiO2 composite films exhibit significantly narrow band gap energy. The film prepared in an electrolyte consisting of NaVO3 with a concentration of 8.54 g/L exhibits the narrowest band gap energy, which is approximately 1.89 eV. The V2Os/TiO2 composite films also have the significantly enhanced visible light photocatalytic activity. The film prepared in an electrolyte consisting of NaVO3 with a concentration of 8.54 g/L exhibits the best photocatalytic activity and about 93% of rhodamine is degraded after 14 h visible light radiation.
文摘The method is based on the oxidation of chlorpromazine with ammonium metavanadate in pH 2.4 solution, the absorbance of coloured compound was measured at 530 nm. Calibration graphs are linear over the concentration range 0 to approximately 250 mu g/mL. The apparent molar absorptivity was 1.28 multiplied by 10**3 L center dot mol** minus **1 center dot cm** minus **1. The proposed method was applied to the determination of chlorpromazine tablets with satisfactory results. (Author abstract) 4 Refs.
