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
A new magnetic mesoporous As(Ⅲ)adsorbent of Fe_(3)O_(4)@SiO_(2)@Ce-ZrO_(2)was prepared by solvothermal and sol^(-)gel method.The core-shell adsorbent presented a high specific surface area(168.2 m^(2)/g)and fast magn...A new magnetic mesoporous As(Ⅲ)adsorbent of Fe_(3)O_(4)@SiO_(2)@Ce-ZrO_(2)was prepared by solvothermal and sol^(-)gel method.The core-shell adsorbent presented a high specific surface area(168.2 m^(2)/g)and fast magnetic separation performance(5.37 A·m^(2)/kg).Compared with Fe_(3)O_(4)@SiO_(2)@ZrO_(2),the Ce-doped sample exhibited 12%-23%increase in As(Ⅲ)uptake over p H 3-11,which was mainly attributed to the formation of bimetal M—O—As complexes.The coexisted SO^_(4)(2-)and PO^_(4)(3-)weakened As(Ⅲ)adsorption,Ca^(2+)worked oppositely,but the impact of Cl^(-)and NO_(3)^(-)was negligible.The As(Ⅲ)maximum adsorption capacity was 24.52 mg/g at 313 K with an initial As(Ⅲ)concentration of 5 mg/L at pH 7,and its kinetics was well fitted by the pseudo-second-order model.Moreover,the adsorbent exhibited remarkable recyclability.It is suggested that Fe_(3)O_(4)@SiO_(2)@Ce-ZrO_(2)is a promising adsorbent for the advanced treatment of As(Ⅲ)contaminated wastewater.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.
基金the financial support from the Open Research Fund of Jiangsu Key Laboratory of Resources and Environmental Information Engineering,China(No.JS201810)。
文摘A new magnetic mesoporous As(Ⅲ)adsorbent of Fe_(3)O_(4)@SiO_(2)@Ce-ZrO_(2)was prepared by solvothermal and sol^(-)gel method.The core-shell adsorbent presented a high specific surface area(168.2 m^(2)/g)and fast magnetic separation performance(5.37 A·m^(2)/kg).Compared with Fe_(3)O_(4)@SiO_(2)@ZrO_(2),the Ce-doped sample exhibited 12%-23%increase in As(Ⅲ)uptake over p H 3-11,which was mainly attributed to the formation of bimetal M—O—As complexes.The coexisted SO^_(4)(2-)and PO^_(4)(3-)weakened As(Ⅲ)adsorption,Ca^(2+)worked oppositely,but the impact of Cl^(-)and NO_(3)^(-)was negligible.The As(Ⅲ)maximum adsorption capacity was 24.52 mg/g at 313 K with an initial As(Ⅲ)concentration of 5 mg/L at pH 7,and its kinetics was well fitted by the pseudo-second-order model.Moreover,the adsorbent exhibited remarkable recyclability.It is suggested that Fe_(3)O_(4)@SiO_(2)@Ce-ZrO_(2)is a promising adsorbent for the advanced treatment of As(Ⅲ)contaminated wastewater.
