Extraction of cesium from nitric acid solutions by bis-[4(5),4′(5′)-alkanoylbenzo]-21-crown-7 in nitrobenzene or nitromethane was investigated.The results show that under the conditions of higher acidity and higher ...Extraction of cesium from nitric acid solutions by bis-[4(5),4′(5′)-alkanoylbenzo]-21-crown-7 in nitrobenzene or nitromethane was investigated.The results show that under the conditions of higher acidity and higher sodium concentration,the extraction efficiency of bis-[4(5),4′(5′)-alkanoylbenzo]-21-crown-7 was superior to that of DB21C7.The composition of the complexes was determined indirectly by measuring the conductance of cesium nitrate-crown ether in nitromethane solution.It indicated that these crown ethers probably formed 1∶1∶1 Cs^+∶crown∶nitrae complex ion pair in the organic phase.The extraction equilibrium was also discussed.展开更多
The Schiff base containing pendant monoaza crown ether HL 1, HL 2, HL 3 and HL 4 have been synthesized by condensation of salicylaldehyde with N (4 aminoaryl)monoaza crown ethers, which were prepared conven...The Schiff base containing pendant monoaza crown ether HL 1, HL 2, HL 3 and HL 4 have been synthesized by condensation of salicylaldehyde with N (4 aminoaryl)monoaza crown ethers, which were prepared conveniently from 4 nitro N,N di(hydroxyethyl)aniline or 4 nitrobenzyl chloride via cyclization or condensation and reduction. The structures of HL 1—HL 4 were verified by 1H NMR, IR spectra, MS and elemental analysis. Moreover, the oxygenation constants ( K O 2 ) and thermodynamic parameters (Δ H 0 and Δ S 0) of their cobalt(II) complexes were determined in the range of -5 ℃ to 25 ℃, and the effect of crown ring bonded to a Schiff base on the dioxygen affinities of cobalt(II) complexes was also observed as compared to the uncrowned analogue (CoL 5 2).展开更多
文摘Extraction of cesium from nitric acid solutions by bis-[4(5),4′(5′)-alkanoylbenzo]-21-crown-7 in nitrobenzene or nitromethane was investigated.The results show that under the conditions of higher acidity and higher sodium concentration,the extraction efficiency of bis-[4(5),4′(5′)-alkanoylbenzo]-21-crown-7 was superior to that of DB21C7.The composition of the complexes was determined indirectly by measuring the conductance of cesium nitrate-crown ether in nitromethane solution.It indicated that these crown ethers probably formed 1∶1∶1 Cs^+∶crown∶nitrae complex ion pair in the organic phase.The extraction equilibrium was also discussed.
基金ProjectsupportedbytheNationalNaturalScienceFoundationofChina (No .2 95 72 0 5 9)
文摘The Schiff base containing pendant monoaza crown ether HL 1, HL 2, HL 3 and HL 4 have been synthesized by condensation of salicylaldehyde with N (4 aminoaryl)monoaza crown ethers, which were prepared conveniently from 4 nitro N,N di(hydroxyethyl)aniline or 4 nitrobenzyl chloride via cyclization or condensation and reduction. The structures of HL 1—HL 4 were verified by 1H NMR, IR spectra, MS and elemental analysis. Moreover, the oxygenation constants ( K O 2 ) and thermodynamic parameters (Δ H 0 and Δ S 0) of their cobalt(II) complexes were determined in the range of -5 ℃ to 25 ℃, and the effect of crown ring bonded to a Schiff base on the dioxygen affinities of cobalt(II) complexes was also observed as compared to the uncrowned analogue (CoL 5 2).
