TiO2/V2O5 catalyst doped with rare earth ions was prepared by sol-gel method. Titanium tetrapropoxide and vanadium pentoxide were used as precursor of the composite catalyst and rare earth ions were used as dopant. Th...TiO2/V2O5 catalyst doped with rare earth ions was prepared by sol-gel method. Titanium tetrapropoxide and vanadium pentoxide were used as precursor of the composite catalyst and rare earth ions were used as dopant. The crystal phases, crystalline sizes, microstructure, absorption spectra of doped composite catalyst were studied by XRD, EDS, FT-IR and UV-Vis. Photoactivity of the prepared catalyst under ultraviolet irradiation were evaluated by degradation of methyl orange （MO） in aqueous solution. It is shown that the prepared catalyst is composed of anatase and futile. The rare earth ions are highly dispersed in composite catalyst. All the doped catalysts appear higher photocatalytic activity than TiO2/V2O5 catalyst and catalyst doped with Ce^4＋ present the best activity to MO.展开更多
The process of pressure leaching the converter vanadium slag with waste titanium dioxide without roasting was studied. Mineralogy analysis indicates that the con- verter vanadium slag contains mainly three mineral pha...The process of pressure leaching the converter vanadium slag with waste titanium dioxide without roasting was studied. Mineralogy analysis indicates that the con- verter vanadium slag contains mainly three mineral phases： magnetite, titanium magnetite, and silicate phase. Vana- dium is in combination with iron, titanium, manganese, aluminum, and silicon. The impacts of leaching tempera- ture, leaching time, stirring speed, liquid-to-solid ratio, and initial leaching agent concentration were investigated on the waste titanium dioxide leaching process. The results indi- cate that under the optimal conditions, the vanadium and the iron leaching rates are 96.85 % and 93.50 %, respectively, and the content of titanium is 12.6 % in the residue. The main mineral phases for the residues under the optimal operation conditions are quartz, ilmenite, anatase, and sili- cate phase, and the residues can be reused as the extraction of titanium raw materials for titanium dioxide production technology by the sulfate method.展开更多
The effect of chemical composition of highly active supported Ziegler-Natta catalysts with controlled morphology on the MWD of PE has been studied.It was shown the variation of transition metal compound in the MgCl_2-...The effect of chemical composition of highly active supported Ziegler-Natta catalysts with controlled morphology on the MWD of PE has been studied.It was shown the variation of transition metal compound in the MgCl_2-supported catalyst affect of MWD of PE produced in broad range:Vanadium-magnesium catalyst(VMC)produce PE with broad and bimodal MWD(M_w/M_n=14-21).MWD of PE,produced over titanium-magnesium catalyst(TMC)is narrow or medium depending on Ti content in the catalyst(M_w/M_n=3.1-4.8).The oxidation ...展开更多
The aim of this work was to investigate the effects of calcination/acid-activation on the composition, structure, and photocatalytic （PC） reduction property of an anodic oxidation TiO2/Ti film catalyst. The surface ...The aim of this work was to investigate the effects of calcination/acid-activation on the composition, structure, and photocatalytic （PC） reduction property of an anodic oxidation TiO2/Ti film catalyst. The surface morphology and phase composition were examined by scanning electron microscopy and X-ray diffraction. The catalytic property of the film catalysts was evaluated through the removal rate of potassium chromate during the PC reduction process. The results showed that the film catalysts were composed of anatase and rutile TiO2 with a micro-porous surface structure. The calcination treatment increased the content of TiO2 in the film, changed the relative ratio of anatase and rutile TiO2, and decreased the size of the micro pores of the film catalysts. The removal rate of potassium chromate was related to the technique parameters of calcination/acid-activation treatment. When the anodic oxidation TiO2/Ti film catalyst was calcined at 873 K for 30 min and then acid-activated in the concentrated H2SO4 for 60 min, it presented the highest catalytic property, with the removal rate of potassium chromate of 96.3% during the PC reduction process under the experimental conditions.展开更多
Magnesium chloride supported vanadium/titanium bimetallic Ziegler-Natta catalysts with di-i-butyl phthalate as internal donor for copolymerization of ethylene and propylene were prepared. The effects of reaction tempe...Magnesium chloride supported vanadium/titanium bimetallic Ziegler-Natta catalysts with di-i-butyl phthalate as internal donor for copolymerization of ethylene and propylene were prepared. The effects of reaction temperature, ethylene/propylene molar ratio, aluminium/vanadium （Al/V） molar ratio and titanium/vanadium molar ratio on the catalytic activity were investigated. The molecular weight, molecular weight distribution, sequence composition and crystallinity of the products were measured by gel permeation chromatography, ^13C-NMR and differential scanning calorimetry analysis, respectively. In comparison to the vanadium and titanium catalysts, the bimetallic catalyst showed higher catalytic activity and better copolymerization performance. The obtained ethylene/propylene copolymers have high molecular weight （105）, broad molecular weight distribution, high propylene content with random or short blocked sequence structures （rErp = 1.919）, low melting temperatures and low crystallinities （Xc 〈 20%）.展开更多
基金Project supported by the National Natural Science Foundation of China (50571003)
文摘TiO2/V2O5 catalyst doped with rare earth ions was prepared by sol-gel method. Titanium tetrapropoxide and vanadium pentoxide were used as precursor of the composite catalyst and rare earth ions were used as dopant. The crystal phases, crystalline sizes, microstructure, absorption spectra of doped composite catalyst were studied by XRD, EDS, FT-IR and UV-Vis. Photoactivity of the prepared catalyst under ultraviolet irradiation were evaluated by degradation of methyl orange （MO） in aqueous solution. It is shown that the prepared catalyst is composed of anatase and futile. The rare earth ions are highly dispersed in composite catalyst. All the doped catalysts appear higher photocatalytic activity than TiO2/V2O5 catalyst and catalyst doped with Ce^4＋ present the best activity to MO.
基金financially supported by the Chinese National Programs for High Technology Research and Development(Nos.2010AA03A405 and 2012AA062303)the National Natural Science Foundation of China(Nos.U1202274,51004033,51204040,and 50974035)+2 种基金the National Science and Technology Support Program(No.2012BAE01B02)the Fundamental Research Funds for the Central Universities(No.N100302005)the Doctoral Fund Project(No.20120042110011)
文摘The process of pressure leaching the converter vanadium slag with waste titanium dioxide without roasting was studied. Mineralogy analysis indicates that the con- verter vanadium slag contains mainly three mineral phases： magnetite, titanium magnetite, and silicate phase. Vana- dium is in combination with iron, titanium, manganese, aluminum, and silicon. The impacts of leaching tempera- ture, leaching time, stirring speed, liquid-to-solid ratio, and initial leaching agent concentration were investigated on the waste titanium dioxide leaching process. The results indi- cate that under the optimal conditions, the vanadium and the iron leaching rates are 96.85 % and 93.50 %, respectively, and the content of titanium is 12.6 % in the residue. The main mineral phases for the residues under the optimal operation conditions are quartz, ilmenite, anatase, and sili- cate phase, and the residues can be reused as the extraction of titanium raw materials for titanium dioxide production technology by the sulfate method.
文摘The effect of chemical composition of highly active supported Ziegler-Natta catalysts with controlled morphology on the MWD of PE has been studied.It was shown the variation of transition metal compound in the MgCl_2-supported catalyst affect of MWD of PE produced in broad range:Vanadium-magnesium catalyst(VMC)produce PE with broad and bimodal MWD(M_w/M_n=14-21).MWD of PE,produced over titanium-magnesium catalyst(TMC)is narrow or medium depending on Ti content in the catalyst(M_w/M_n=3.1-4.8).The oxidation ...
基金supported by the National High Technology Research and Development Program of China (No. 2007AA03Z337)the Harbin Special Creation Foundation for Science and Technology of Fellow in China (No. 2006RFQXG032)
文摘The aim of this work was to investigate the effects of calcination/acid-activation on the composition, structure, and photocatalytic （PC） reduction property of an anodic oxidation TiO2/Ti film catalyst. The surface morphology and phase composition were examined by scanning electron microscopy and X-ray diffraction. The catalytic property of the film catalysts was evaluated through the removal rate of potassium chromate during the PC reduction process. The results showed that the film catalysts were composed of anatase and rutile TiO2 with a micro-porous surface structure. The calcination treatment increased the content of TiO2 in the film, changed the relative ratio of anatase and rutile TiO2, and decreased the size of the micro pores of the film catalysts. The removal rate of potassium chromate was related to the technique parameters of calcination/acid-activation treatment. When the anodic oxidation TiO2/Ti film catalyst was calcined at 873 K for 30 min and then acid-activated in the concentrated H2SO4 for 60 min, it presented the highest catalytic property, with the removal rate of potassium chromate of 96.3% during the PC reduction process under the experimental conditions.
基金supported by the Program for New Century Excellent Talents in Universities(NCET-07-0142)the Program for New Century Excellent Talents in Heilongjiang Provincial Universities(NCET-06-010)+1 种基金the National Natural Science Foundation of China(No.20972025)the Science Foundation of Tianjin University of Science & Technology(No.20090420)
文摘Magnesium chloride supported vanadium/titanium bimetallic Ziegler-Natta catalysts with di-i-butyl phthalate as internal donor for copolymerization of ethylene and propylene were prepared. The effects of reaction temperature, ethylene/propylene molar ratio, aluminium/vanadium （Al/V） molar ratio and titanium/vanadium molar ratio on the catalytic activity were investigated. The molecular weight, molecular weight distribution, sequence composition and crystallinity of the products were measured by gel permeation chromatography, ^13C-NMR and differential scanning calorimetry analysis, respectively. In comparison to the vanadium and titanium catalysts, the bimetallic catalyst showed higher catalytic activity and better copolymerization performance. The obtained ethylene/propylene copolymers have high molecular weight （105）, broad molecular weight distribution, high propylene content with random or short blocked sequence structures （rErp = 1.919）, low melting temperatures and low crystallinities （Xc 〈 20%）.
