The extraction of L-Arginine with di(2-ethylhexyl)phosphoric acid(D2EHPA) has been studied as functions of equilibrium pH, D2EHPA concentration, L-Arginine equilibrium concentration, NH 4Cl concentration and temperatu...The extraction of L-Arginine with di(2-ethylhexyl)phosphoric acid(D2EHPA) has been studied as functions of equilibrium pH, D2EHPA concentration, L-Arginine equilibrium concentration, NH 4Cl concentration and temperature. The beffer extraction results were obtained in condition of pH=5~7, D2EHPA 0.2~0.4 mol/L, NH 4Cl<0.2 mol/L and low temperature. The equilibrium concentration of L-Arg depends on the saturation extraction capacity.展开更多
Solvent extraction equilibria of four main alkaline earth metals(magnesium, calcium, strontium and barium) with di (2-ethylhexyl)phosphoric acid (DEHPA), 2-ethylhexyl phosphonic acidmono-(2-ethylhexyl) esters, di (2, ...Solvent extraction equilibria of four main alkaline earth metals(magnesium, calcium, strontium and barium) with di (2-ethylhexyl)phosphoric acid (DEHPA), 2-ethylhexyl phosphonic acidmono-(2-ethylhexyl) esters, di (2, 4, 4-tri-methylpentyl) phosphinicacid and IR spectra of the extracts have been studied. Theselectivity order is dependent on the e/r value and hydration energyof the metal ions. The minor shift of the P→O in IR absorption ofthe alkaline earth metal extracts indicates that the interactionbetween the metal ions and P→O is much weaker for alkaline earthmetals than for transitional metals.展开更多
Di(2-ethylhexyl)phosphoric acid was used as extractant of bismuth ions from nitrate medium by emulsion liquid membrane, with Triton X-100 as the biodegradable surfactant in n-pentanol bulk membrane. The novelties an...Di(2-ethylhexyl)phosphoric acid was used as extractant of bismuth ions from nitrate medium by emulsion liquid membrane, with Triton X-100 as the biodegradable surfactant in n-pentanol bulk membrane. The novelties and innovative points of this work are the application of emulsion liquid membrane for selective and efficient extraction of bismuth ions as well as the relevant optimization procedures. The extraction of bismuth ions was evaluated by the yield of extraction. The experimental parameters were evaluated and optimized, including the ratio of di(2-ethylhexyl)phosphoric acid mass concentration to Triton X-100 (1.0%:0.5%), nature of diluent (n-pentanol), nature and concentration of stripping solution (sulfuric acid, 0.5 mol. L-1), stirring speed (1800 r.min 1) and equilibrium time of extraction (20 min), initial feed solution of bismuth (350 mg-L 1) and the volume ratio of internal stripping phase to membrane phase (14). The experimental parameters of kinetic extraction reveal that the bismuth ions can be extracted bv 100%.展开更多
Separation of trivalent lanthanides (Ln(Ⅲ)) and actinides (An(Ⅲ)) is a key issue in the advanced spent nuclear fuel repro- cessing. In the well-known trivalent actinide lanthanide separation by phosphorus re...Separation of trivalent lanthanides (Ln(Ⅲ)) and actinides (An(Ⅲ)) is a key issue in the advanced spent nuclear fuel repro- cessing. In the well-known trivalent actinide lanthanide separation by phosphorus reagent extraction from aqueous komplexes (TALSPEAK) process, the organophosphorus ligand HDEHP (di-(2-ethylhexyl) phosphoric acid) has been used as an efficient reagent for the partitioning of Ln(Ⅲ) from An(Ⅲ) with the combination of a holdback reagent in aqueous lactate buffer solu- tion. In this work, the structural and electronic properties of Eu3+ and Am3+ complexes with HDEHP in nitric acid solution have been systematically explored by using scalar-relativistic density functional theory (DFT). It was found that HDEHP can coordinate with M(Ⅲ) (M=Eu, Am) cations in the form of hydrogen-bonded dimers HL2 (L=DEHP), and the metal ions pre- fer to coordinate with the phosphoryl oxygen atom of the ligand. For all the extraction complexes, the metal-ligand bonds are mainly ionic in nature. Although Eu(Ⅲ) complexes have higher interaction energies, the HL2- dimer shows comparable affini- ty for Eu(Ⅲ) and Am(Ⅲ) according to thermodynamic analysis, nonahydrate. It is expected that this work could provide insightful HDEHP at the molecular level. which may be attributed to the higher stabilities of Eu(Ⅲ) information on the complexation of An(Ⅲ) and Ln(Ⅲ) with展开更多
文摘The extraction of L-Arginine with di(2-ethylhexyl)phosphoric acid(D2EHPA) has been studied as functions of equilibrium pH, D2EHPA concentration, L-Arginine equilibrium concentration, NH 4Cl concentration and temperature. The beffer extraction results were obtained in condition of pH=5~7, D2EHPA 0.2~0.4 mol/L, NH 4Cl<0.2 mol/L and low temperature. The equilibrium concentration of L-Arg depends on the saturation extraction capacity.
基金the National Natural Science Foundation of China (No. 50074028).
文摘Solvent extraction equilibria of four main alkaline earth metals(magnesium, calcium, strontium and barium) with di (2-ethylhexyl)phosphoric acid (DEHPA), 2-ethylhexyl phosphonic acidmono-(2-ethylhexyl) esters, di (2, 4, 4-tri-methylpentyl) phosphinicacid and IR spectra of the extracts have been studied. Theselectivity order is dependent on the e/r value and hydration energyof the metal ions. The minor shift of the P→O in IR absorption ofthe alkaline earth metal extracts indicates that the interactionbetween the metal ions and P→O is much weaker for alkaline earthmetals than for transitional metals.
文摘Di(2-ethylhexyl)phosphoric acid was used as extractant of bismuth ions from nitrate medium by emulsion liquid membrane, with Triton X-100 as the biodegradable surfactant in n-pentanol bulk membrane. The novelties and innovative points of this work are the application of emulsion liquid membrane for selective and efficient extraction of bismuth ions as well as the relevant optimization procedures. The extraction of bismuth ions was evaluated by the yield of extraction. The experimental parameters were evaluated and optimized, including the ratio of di(2-ethylhexyl)phosphoric acid mass concentration to Triton X-100 (1.0%:0.5%), nature of diluent (n-pentanol), nature and concentration of stripping solution (sulfuric acid, 0.5 mol. L-1), stirring speed (1800 r.min 1) and equilibrium time of extraction (20 min), initial feed solution of bismuth (350 mg-L 1) and the volume ratio of internal stripping phase to membrane phase (14). The experimental parameters of kinetic extraction reveal that the bismuth ions can be extracted bv 100%.
基金the National Natural Science Foundation of China (21201166, 11275090)the Major Research Plan of Natural Science Foundation of China (91426302, 91326202)+2 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA030104)the Natural Science Foundation of Hunan Province (12JJ9006)the Scientific Research Fund of Hunan Provincial Education Department (12A116)
文摘Separation of trivalent lanthanides (Ln(Ⅲ)) and actinides (An(Ⅲ)) is a key issue in the advanced spent nuclear fuel repro- cessing. In the well-known trivalent actinide lanthanide separation by phosphorus reagent extraction from aqueous komplexes (TALSPEAK) process, the organophosphorus ligand HDEHP (di-(2-ethylhexyl) phosphoric acid) has been used as an efficient reagent for the partitioning of Ln(Ⅲ) from An(Ⅲ) with the combination of a holdback reagent in aqueous lactate buffer solu- tion. In this work, the structural and electronic properties of Eu3+ and Am3+ complexes with HDEHP in nitric acid solution have been systematically explored by using scalar-relativistic density functional theory (DFT). It was found that HDEHP can coordinate with M(Ⅲ) (M=Eu, Am) cations in the form of hydrogen-bonded dimers HL2 (L=DEHP), and the metal ions pre- fer to coordinate with the phosphoryl oxygen atom of the ligand. For all the extraction complexes, the metal-ligand bonds are mainly ionic in nature. Although Eu(Ⅲ) complexes have higher interaction energies, the HL2- dimer shows comparable affini- ty for Eu(Ⅲ) and Am(Ⅲ) according to thermodynamic analysis, nonahydrate. It is expected that this work could provide insightful HDEHP at the molecular level. which may be attributed to the higher stabilities of Eu(Ⅲ) information on the complexation of An(Ⅲ) and Ln(Ⅲ) with