Study on the extraction and separation of rare earth with new extractants is important in the rare earth chemistry and nuclear reprocessing. In this work, the extraction of Ce?with N,N,N′,N′ tetrabutylmalonamide (TB...Study on the extraction and separation of rare earth with new extractants is important in the rare earth chemistry and nuclear reprocessing. In this work, the extraction of Ce?with N,N,N′,N′ tetrabutylmalonamide (TBMA) in toluene from nitrate media has been investigated. The effect of the concentration of nitric acid, TBMA and salting out agent (LiNO3) and also the temperature on the distribution ratios was examined. The stoichiometries of the extracted complexes were determined to be Ce(NO3)3·3TBMA and Ce(NO3)3·4TBMA, respectively. The ap<IMG SRC="IMAGE/06170035.JPG" HEIGHT=11 WIDTH=24>parent extraction constants and the enthalpy of the extraction were calculated based on the extraction data, which are logKex1=3.97, logKex2=4.75 and =-31.25kJ·mol-1, respectively. The IR spectra of the loaded organic phase supported the suggested extraction mechanism.展开更多
This study demonstrates the preparation and characterization of a novel ion imprinted cryogel which exhibits high affinity and selectivity towards Ce（Ⅲ） ions in aqueous solutions and bastnasite ore samples.2-Hydrox...This study demonstrates the preparation and characterization of a novel ion imprinted cryogel which exhibits high affinity and selectivity towards Ce（Ⅲ） ions in aqueous solutions and bastnasite ore samples.2-Hydroxyethyl methacrylate（HEMA） and N-methacryloylamido antipyrine（MAAP） were used as functional monomers for the preparation of Ce（Ⅲ） imprinted cryogel. The effects of various factors such as initial Ce（Ⅲ） concentration, flow rate, pH, interaction time and ionic strength on the Ce（Ⅲ） binding to the prepared ion imprinted cryogels were also studied. The binding equilibrium for Ce（Ⅲ） is obtained in30 min at the flow rate of 0.5 mL/min. The maximum binding capacity of the prepared ion imprinted cryogel towards Ce（Ⅲ） is obtained as 36.58 mg/g at optimum conditions. The selectivity of the prepared ion imprinted cryogel towards Ce（Ⅲ） in the presence of other possible interfering lanthanide ions such as La（Ⅲ） and Nd（Ⅲ） were also performed. The obtained results showed that the prepared ion imprinted cryogel exhibits high selectivity and sensitivity towards Ce（Ⅲ） ions. The limit of detection（LOD） was found as 50 μg/L.展开更多
A column chromatographic method has been developed for the separation and determination of cerium(Ⅲ) using poly[dibenzo-18-crown-6].The separation was carried out in L-valine medium.The adsorption of cerium(Ⅲ) was q...A column chromatographic method has been developed for the separation and determination of cerium(Ⅲ) using poly[dibenzo-18-crown-6].The separation was carried out in L-valine medium.The adsorption of cerium(Ⅲ) was quantitative from 1×10-1 to 1×10-4 mol/L L-valine.Amongst the various eluents,1.0-8.0 mol/L hydrochloric acid,1.0-8.0 mol/L hydrobromic acid,1.0-8.0 mol/L perchloric acid,1.0-2.0 mol/L sulfuric acid and 4.0-5.0 mol/L acetic acid,were found to be the efficient eluents for cerium(Ⅲ).The capacity of poly[dibenzo-18-crown-6] for cerium(Ⅲ) was(0.428±0.01) mmol/g.The method was applied to the separation of cerium(Ⅲ) from associated elements link uranium(Ⅵ) and thorium(Ⅳ).It was also applied for the determination of cerium(Ⅲ) in geological samples.The method is simple,rapid and selective with good reproducibility(approximately±2%).展开更多
Two high coordination crystals were obtained by the interaction of Ce^（3＋） and Nd^（3＋） with polypyridyl quinoxaline ligand 2,3,6,7,10,11-hexakis（2-pyridyl）dipyrazino[2,3-f：20,30-h]quinoxaline（HPDQ）, and the...Two high coordination crystals were obtained by the interaction of Ce^（3＋） and Nd^（3＋） with polypyridyl quinoxaline ligand 2,3,6,7,10,11-hexakis（2-pyridyl）dipyrazino[2,3-f：20,30-h]quinoxaline（HPDQ）, and they were characterized. Complex 1 exhibits a 0 dimensional three-nuclear structure, with the three Ce（Ⅲ） atoms being ten-, eleven- and twelve-coordinated. Complex 2 is a 0 dimensional dual-core structure and the Nd（Ⅲ） atom is ten-coordinated. Complex 1 is of monoclinic system, space group P2/c with a = 16.850（3）, b = 16.617（3）, c = 24.017（5） ？, β = 100.94（3）o, V = 6602（2） ？~3, Z = 4, S = 1.062, F（000） = 3372, R = 0.0504 and wR = 0.1463（I 〉 2σ（I））. Complex 2 adopts a monoclinic system, space group C2/c with a = 25.795（5）, b = 20.166（4）, c = 13.059（3） ？, β = 112.29（3）°, V = 6286（2） ？~3, Z = 4, S = 1.004, F（000） = 2664, R = 0.0663 and wR = 0.1821（I 〉 2σ（I））. Furthermore, the behaviors of HPDQ with Ce^（3＋） and Nd^（3＋） in the solution are also investigated. After the Ce^（3＋） is added, the ultraviolet absorption of the solution is enhanced with a red shift compared with that of the HPDQ ligand. While after adding Nd^（3＋）, the ultraviolet absorption of the solution is weakened, and it has a red shift which is the same as Ce^（3＋）. However, after the respective addition of metal ions, the emission of all solutions is quenched and has a red shift compared with that of the HPDQ ligand.展开更多
文摘Study on the extraction and separation of rare earth with new extractants is important in the rare earth chemistry and nuclear reprocessing. In this work, the extraction of Ce?with N,N,N′,N′ tetrabutylmalonamide (TBMA) in toluene from nitrate media has been investigated. The effect of the concentration of nitric acid, TBMA and salting out agent (LiNO3) and also the temperature on the distribution ratios was examined. The stoichiometries of the extracted complexes were determined to be Ce(NO3)3·3TBMA and Ce(NO3)3·4TBMA, respectively. The ap<IMG SRC="IMAGE/06170035.JPG" HEIGHT=11 WIDTH=24>parent extraction constants and the enthalpy of the extraction were calculated based on the extraction data, which are logKex1=3.97, logKex2=4.75 and =-31.25kJ·mol-1, respectively. The IR spectra of the loaded organic phase supported the suggested extraction mechanism.
文摘This study demonstrates the preparation and characterization of a novel ion imprinted cryogel which exhibits high affinity and selectivity towards Ce（Ⅲ） ions in aqueous solutions and bastnasite ore samples.2-Hydroxyethyl methacrylate（HEMA） and N-methacryloylamido antipyrine（MAAP） were used as functional monomers for the preparation of Ce（Ⅲ） imprinted cryogel. The effects of various factors such as initial Ce（Ⅲ） concentration, flow rate, pH, interaction time and ionic strength on the Ce（Ⅲ） binding to the prepared ion imprinted cryogels were also studied. The binding equilibrium for Ce（Ⅲ） is obtained in30 min at the flow rate of 0.5 mL/min. The maximum binding capacity of the prepared ion imprinted cryogel towards Ce（Ⅲ） is obtained as 36.58 mg/g at optimum conditions. The selectivity of the prepared ion imprinted cryogel towards Ce（Ⅲ） in the presence of other possible interfering lanthanide ions such as La（Ⅲ） and Nd（Ⅲ） were also performed. The obtained results showed that the prepared ion imprinted cryogel exhibits high selectivity and sensitivity towards Ce（Ⅲ） ions. The limit of detection（LOD） was found as 50 μg/L.
基金This work was supported by the University Grant Commission for awarding Junior Research Fellowship.
文摘A column chromatographic method has been developed for the separation and determination of cerium(Ⅲ) using poly[dibenzo-18-crown-6].The separation was carried out in L-valine medium.The adsorption of cerium(Ⅲ) was quantitative from 1×10-1 to 1×10-4 mol/L L-valine.Amongst the various eluents,1.0-8.0 mol/L hydrochloric acid,1.0-8.0 mol/L hydrobromic acid,1.0-8.0 mol/L perchloric acid,1.0-2.0 mol/L sulfuric acid and 4.0-5.0 mol/L acetic acid,were found to be the efficient eluents for cerium(Ⅲ).The capacity of poly[dibenzo-18-crown-6] for cerium(Ⅲ) was(0.428±0.01) mmol/g.The method was applied to the separation of cerium(Ⅲ) from associated elements link uranium(Ⅵ) and thorium(Ⅳ).It was also applied for the determination of cerium(Ⅲ) in geological samples.The method is simple,rapid and selective with good reproducibility(approximately±2%).
基金supported by the NNSFC(21301100)the Education Department Fund of Henan(13A150819)Special fund of Nanyang Normal University(ZX2013029)
文摘Two high coordination crystals were obtained by the interaction of Ce^（3＋） and Nd^（3＋） with polypyridyl quinoxaline ligand 2,3,6,7,10,11-hexakis（2-pyridyl）dipyrazino[2,3-f：20,30-h]quinoxaline（HPDQ）, and they were characterized. Complex 1 exhibits a 0 dimensional three-nuclear structure, with the three Ce（Ⅲ） atoms being ten-, eleven- and twelve-coordinated. Complex 2 is a 0 dimensional dual-core structure and the Nd（Ⅲ） atom is ten-coordinated. Complex 1 is of monoclinic system, space group P2/c with a = 16.850（3）, b = 16.617（3）, c = 24.017（5） ？, β = 100.94（3）o, V = 6602（2） ？~3, Z = 4, S = 1.062, F（000） = 3372, R = 0.0504 and wR = 0.1463（I 〉 2σ（I））. Complex 2 adopts a monoclinic system, space group C2/c with a = 25.795（5）, b = 20.166（4）, c = 13.059（3） ？, β = 112.29（3）°, V = 6286（2） ？~3, Z = 4, S = 1.004, F（000） = 2664, R = 0.0663 and wR = 0.1821（I 〉 2σ（I））. Furthermore, the behaviors of HPDQ with Ce^（3＋） and Nd^（3＋） in the solution are also investigated. After the Ce^（3＋） is added, the ultraviolet absorption of the solution is enhanced with a red shift compared with that of the HPDQ ligand. While after adding Nd^（3＋）, the ultraviolet absorption of the solution is weakened, and it has a red shift which is the same as Ce^（3＋）. However, after the respective addition of metal ions, the emission of all solutions is quenched and has a red shift compared with that of the HPDQ ligand.
