A new approach was proposed for grouping separation of 14 lanthanide rare-earth ions from their coexisting mixed aqueous solutions, by performing liquid-column elution using the aqueous solution containing 14 lanthani...A new approach was proposed for grouping separation of 14 lanthanide rare-earth ions from their coexisting mixed aqueous solutions, by performing liquid-column elution using the aqueous solution containing 14 lanthanide rare-earth ions as the stationary phase and the dispersed organic oil droplets containing P507 extractant as the mobile phase. It was revealed that 14 lanthanide rare-earth ions could be separated into four groups, according to the lanthanide tetrad effect, respectively eluting out from the liquid column at different time in a certain order. Various effects including the saponification degree of P507, the concentration of P507 in organic phase, the length and inner diameter of the extraction column on the performance of grouping separation of rare-earth ions were discussed. The changes of the mass transfer coefficients were also investigated. The separation efficiency of the four groups of rareearth elements(REEs) was evaluated based on the elution resolution, Rs, of the elution peaks of La(Ⅲ),Gd(Ⅲ), Ho(Ⅲ) and Lu(Ⅲ), the four representative elements respectively from each of the four groups of REEs. Experimental results demonstrated that the separation of REEs by liquid-column elution mainly depended on the competitive adsorption of different rare-earth groups onto the surface of ascending P507 oil droplets. The affinity of different rare-earth groups with P507 extractant and a limited adsorption capacity of P507 molecules at the surface of the oil droplets ascending in liquid column play the important role. The present work highlights a promising technique for grouping separation of multiple lanthanide elements co-existing complex systems.展开更多
Coordination polymerization of renewable β-ocimene has been investigated using asymmetric diiminophosphinate lutetium complex1, β-diketiminate yttrium complex 2, bis(phosphino)carbazolide yttrium complex 3, half-san...Coordination polymerization of renewable β-ocimene has been investigated using asymmetric diiminophosphinate lutetium complex1, β-diketiminate yttrium complex 2, bis(phosphino)carbazolide yttrium complex 3, half-sandwich benzyl fluorenyl scandium complex 4 and pyridyl-methylene-fluorenyl rare-metal complexes 5a–5c. Complexes 1, 4 and 5a–5c show trans-1,2-regioselectivities and high activities, of which 5c exhibits excellent isoselectivity(mmmm>99%). Conversely, complexes 2 and 3 promote β-ocimene polymerization to produce isotactic cis-1,4-polyocimenes(cis-1,4>99%, mm>95%). Diblock copolymers cis-1,4-PIP-block-cis-1,4-POc and cis-1,4-PBD-block-cis-1,4-POc are obtained in one-pot reactions of β-ocimene with isoprene and butadiene using complex 3. Epoxidation and hydroxylation of polyocimene afford functionalized polyolefins with enhanced T_(g)(from-20 ℃ to 79 ℃ and 74 ℃) and hydrophilicity.展开更多
基金Supported by the National Natural Science Foundation of China(51574213,51074150)the Key Project of Chinese National Programs for Fundamental Research and Development(2012CBA01203)
文摘A new approach was proposed for grouping separation of 14 lanthanide rare-earth ions from their coexisting mixed aqueous solutions, by performing liquid-column elution using the aqueous solution containing 14 lanthanide rare-earth ions as the stationary phase and the dispersed organic oil droplets containing P507 extractant as the mobile phase. It was revealed that 14 lanthanide rare-earth ions could be separated into four groups, according to the lanthanide tetrad effect, respectively eluting out from the liquid column at different time in a certain order. Various effects including the saponification degree of P507, the concentration of P507 in organic phase, the length and inner diameter of the extraction column on the performance of grouping separation of rare-earth ions were discussed. The changes of the mass transfer coefficients were also investigated. The separation efficiency of the four groups of rareearth elements(REEs) was evaluated based on the elution resolution, Rs, of the elution peaks of La(Ⅲ),Gd(Ⅲ), Ho(Ⅲ) and Lu(Ⅲ), the four representative elements respectively from each of the four groups of REEs. Experimental results demonstrated that the separation of REEs by liquid-column elution mainly depended on the competitive adsorption of different rare-earth groups onto the surface of ascending P507 oil droplets. The affinity of different rare-earth groups with P507 extractant and a limited adsorption capacity of P507 molecules at the surface of the oil droplets ascending in liquid column play the important role. The present work highlights a promising technique for grouping separation of multiple lanthanide elements co-existing complex systems.
基金financially supported by the open research fund program of Science and Technology on Aerospace Chemical Power Laboratory (No. STACPL120221B03)the National Natural Science Foundation of China (Nos. s22175059,52073275 and U21A20279)。
文摘Coordination polymerization of renewable β-ocimene has been investigated using asymmetric diiminophosphinate lutetium complex1, β-diketiminate yttrium complex 2, bis(phosphino)carbazolide yttrium complex 3, half-sandwich benzyl fluorenyl scandium complex 4 and pyridyl-methylene-fluorenyl rare-metal complexes 5a–5c. Complexes 1, 4 and 5a–5c show trans-1,2-regioselectivities and high activities, of which 5c exhibits excellent isoselectivity(mmmm>99%). Conversely, complexes 2 and 3 promote β-ocimene polymerization to produce isotactic cis-1,4-polyocimenes(cis-1,4>99%, mm>95%). Diblock copolymers cis-1,4-PIP-block-cis-1,4-POc and cis-1,4-PBD-block-cis-1,4-POc are obtained in one-pot reactions of β-ocimene with isoprene and butadiene using complex 3. Epoxidation and hydroxylation of polyocimene afford functionalized polyolefins with enhanced T_(g)(from-20 ℃ to 79 ℃ and 74 ℃) and hydrophilicity.