Phase separation rate is a critical character in determining the usefulness of a solvent extraction system in hydrometallurgy. A survey of the synergistic mixture containing dinonylnaphthalene sulfonic acid (HDNNS) an...Phase separation rate is a critical character in determining the usefulness of a solvent extraction system in hydrometallurgy. A survey of the synergistic mixture containing dinonylnaphthalene sulfonic acid (HDNNS) and 2-ethylhexly 4-pyridinecarboxylate ester (4PC) for the extraction of cobalt from acidic single metal sulfate solution was carried out to suggest how the physicochemical properties and the morphology of the reverse micelles in the loaded organic phase affect the phase separation. The results show that effective parameters affecting the phase separation are the viscosity and the excess water uptake of the loaded organic phase. It is obvious that the specific settling rate (SSR) decreases with the apparent increase of these two parameters. The measurement of small angle X-ray scattering (SAXS) proves that the morphology of the reversed micelles in the loaded organic phase changes evidently with the change of the specific settling rate (SSR).展开更多
A rapid, cost effective and reliable analytical method was developed and validated for the simultaneous determination of four estrogens (17 β-estradiol, 17 α-ethinylestradiol, estrone, and estriol) in compost sample...A rapid, cost effective and reliable analytical method was developed and validated for the simultaneous determination of four estrogens (17 β-estradiol, 17 α-ethinylestradiol, estrone, and estriol) in compost samples from the biodegradation of biological infectious hazardous wastes. Ultrasonic solvent extraction, using methanol as extraction solvent, coupled with SPE clean-up, using cartridges HLB 60 mg - 6 ml Supelco®<sup></sup> and acetonitrile for reconstitution of eluents, was used for the simultaneous extraction of the four estrogens. Mean recoveries in the range of 98% - 107% were obtained. All compounds were separated in a single gradient run by UHPLC Kinetex<sup>TM</sup> 2.6 μm XB-C18 100 ÅLC (50 × 4.6 mm) column. Analytes were detected via multiple reaction monitoring (MRM) using an AB SCIEX API-5000TM triple quadrupole (Applied Biosystems/MDS SCIEX) with electrospray ionization in negative mode. Isocratic mobile phase of Water:ACN (50:50) resulted to be the optimum. Limits of detection and quantification were on the order of 0.66 ng·g<sup>-1</sup> and 2 ng·g<sup>-1</sup> for all the estrogens. These limits were lower than most of the values reported in the literature for similar matrices. Suitable level of linearity, good repeatability and reproducibility with coefficients of variation is lower than 11.7%, 6.8% and 8.3%, respectively.展开更多
Dummy molecularly imprinted polymers （DMIPs） for 4-（methylnitrosamino）-1-（3-pyridyl）-1-butanol （NNAL） were produced using three structural analogues as dummy template molecules. The chosen analogues were 4-（a...Dummy molecularly imprinted polymers （DMIPs） for 4-（methylnitrosamino）-1-（3-pyridyl）-1-butanol （NNAL） were produced using three structural analogues as dummy template molecules. The chosen analogues were 4-（acetymethylamino）-1-（3-pyridyl）-butanol, 4- （methylamino）-1-（3-pyridyl）-1-butanol, and 1-（3-pyridyl）-1,4,-butanediol. The molecular recognition characteristics of the produced polymers were evaluated by X-ray photoelec- tron spectroscopy （XPS） and Fourier transform infrared spectroscopy （FT-IR）. Interactions between NNAL and methacrylic acid should be cooperative hydrogen bonds while the ni- trogen atom of the pyridine ring and the oxygen atom of the nitroso group in NNAL are two of the hydrogen-bond acceptors. It was further demonstrated that DMIP synthesized by 4-（acetymethylamino）-1-（3-pyridyl）-butanol had the best binding performance by XPS and FT-IR. Then dummy molecularly imprinted solid phase extraction （DMISPE） was developed for the determination of the analyte using the hit polymer as the sorbing material. Under optimal conditions, the recovery of NNAL dissolved in standard solution reached 93%. And the investigated polymer exhibited much higher binding of NNAL when nicotine was acted as the competitive molecule. Also the proposed method was applied to the measurement of NNAL spiked in blank urine samples with recoveries ranging from 87.2% to 101.2%.展开更多
The influences of solid particles in leach solution on the formation of the third phase crud during solvent extraction of copper were studied. Analyzed from the point of view of pH value and surface tension, the study...The influences of solid particles in leach solution on the formation of the third phase crud during solvent extraction of copper were studied. Analyzed from the point of view of pH value and surface tension, the study results showed that the solid particle is one of the most important contributors for the formation of the third phase crud. During solvent extraction, if the pH value was greater than 2.30, the number of solid particles in the mother solution increased, in which case the possibility of forming the third phase crud could also increase, and the interface tension value might grow in pace with the quantity of the third phase crud.展开更多
Using experimental data from a number of pulsed disc and doughnut solvent extraction columns, a unified correla- tion for the prediction of dispersed phase holdup that considers the effects of mass transfer is present...Using experimental data from a number of pulsed disc and doughnut solvent extraction columns, a unified correla- tion for the prediction of dispersed phase holdup that considers the effects of mass transfer is presented. Pulsed disc and doughnut solvent extraction columns （PDDC） have been used for a range of important applications such as ura- nium extraction and nuclear fuel recycling. Although the dispersed phase holdup in a PDDC has been presented by some researchers, there is still the need to develop a robust correlation that can predict the experimental dispersed phase holdup over a range of operating conditions including the effects of mass transfer direction. In this study, dis- persed phase holdup data from different literature sources for a PDDC were used to refit constants for the correlation presented by Kumar and Hartland lind. Eng. Chem. Res.,27 （1988）,131-138] which did not consider the effect of col- umn geometry. In order to incorporate the characteristic length of the PDDC （i.e. the plate spacing）, the unified cor- relation for holdup proposed by Kumar and Hartland based on data from eight different types of columns [Ind. Eng. Chem. Res.,34 （1995） 3925-3940] was refitted to the PDDC data. New constants have been presented for each hold- up correlation for a PDDC based on regression analysis using published holdup data from PDDCs that cover a range of onerating conditions and nhwical nronerties and consider the direction of mass transfer.展开更多
Extraction of copper and ammonia from Cu2+-NH3-Cl--H2O solution using laboratorialy synthesized sterically hindered β-diketone(4,4-dimethyl-1-(4-dodecylphenyl)-1,3-pentanedione) was studied.The effects of the copper ...Extraction of copper and ammonia from Cu2+-NH3-Cl--H2O solution using laboratorialy synthesized sterically hindered β-diketone(4,4-dimethyl-1-(4-dodecylphenyl)-1,3-pentanedione) was studied.The effects of the copper concentration,the total ammonia concentration,the initial pH in the aqueous phase,the phase ratio,and the temperature on copper extraction ratio and ammonia extraction in loaded organic phase were investigated using this sterically hindered β-diketone.Under the conditions of temperature 25℃,contact time of two phases 30 min,phase ratio 1-1,concentration of copper 3 g/L,concentration of total ammonia 3 mol/L,aqueous pH 8.43,and the concentration of β-diketone in organic phase 20%(volume fraction),ammonia in aqueous phase is much lower to be extracted by organic phase(just 14.5 mg/L),while the extraction rate of copper is 95.09%.展开更多
In order to overcome the difficulty in stripping and reduce the equilibrium time in heavy rare earth separation with acidic organophosphorous extractants, the phase transfer catalysis (PTC) technique was introduced to...In order to overcome the difficulty in stripping and reduce the equilibrium time in heavy rare earth separation with acidic organophosphorous extractants, the phase transfer catalysis (PTC) technique was introduced to the solvent extraction process, especially applied to the stripping section, which was called phase transfer catalysis stripping (PTCS) process. in the PTCS process, an acidic phosphorous extractant was mixed with another extractant which can transfer hydrogen ion from aqueous phase to organic phase and almost does not extract rare earth ions, so that the stripping efficiency can be improved and the stripping extraction equilibrium be accelerated. The reaction mechanism of the PTCS and the requisite properties for a feasible PTCS catalyst in rare earth extraction were studied. We selected D(2)EHPA as the extractant, Alamine 336 as the PTCS catalyst and mixed rare earth chlorides as the feed to test the PTCS phenomenon. Based on the experimental data, the applicability of PTCS technique in rare earth solvent extraction was discussed.展开更多
This work investigated the separation of potassium from sodium in alkaline solution using substituted phenol-based extractants.Superior potassium extraction was achieved with 4-tert-butyl-2-(α-methylbenzyl)phenol(t-B...This work investigated the separation of potassium from sodium in alkaline solution using substituted phenol-based extractants.Superior potassium extraction was achieved with 4-tert-butyl-2-(α-methylbenzyl)phenol(t-BAMBP)than 4-sec-butyl-2-(α-methylbenzyl)phenol(BAMBP).The optimum conditions for the extraction were 1 mol/L t-BAMBP,3:1 volumetric phase ratio(O/A),and two extraction stages.After cross-current extraction,the extraction ratio of potassium reached 90.8%.After scrubbing with deionised water at phase ratio of 4:1 and scrubbing stage of 4,a sodium scrubbing efficiency of 88.2%was obtained.After stripping using 1 mol/L H_(2)SO_(4) at phase ratio of 3:1,the stripping efficiency of potassium reached 94.2%.The potassium/sodium(K/Na)concentration ratio increased 14.3 times from 0.15 in the feed solution to 2.3 in the stripping solution.The efficient separation of potassium from sodium in alkaline solution was achieved via solvent extraction with t-BAMBP.展开更多
In this work, problems encountered by tri-butyl phosphate (TBP) in the industrialization of lithium extraction from salt lake brine were discussed in detail. The behavior of N, N-bi-(2-ethylhexyl) acetamide (N523) dur...In this work, problems encountered by tri-butyl phosphate (TBP) in the industrialization of lithium extraction from salt lake brine were discussed in detail. The behavior of N, N-bi-(2-ethylhexyl) acetamide (N523) during lithium extraction was investigated, and its disadvantages were analyzed in the view of practical application. An N523-TBP mixture extraction system was proposed to alleviate or avoid the defects that N523 and TBP met when they were used separately. The optimal composition of this mixture extraction system was determined to be 20%N523-30%TBP-50% kerosene. The effects of brine acidity, Fe/Li molarity ratio, phase ratio and chloride ion concentration on lithium extraction efficiency were discussed. The operation conditions in single-stage extraction were optimized as brine acidity=0.05 mol/L, Fe/Li molarity ratio=1.3, and phase ratio=2. The high concentration of chloride ions in brine was beneficial for the extraction of lithium. The structure of the extracted complex was proposed as (LiFeCl 4 · n N523 · m TBP)·(2- n )N523 ·(2- m )TBP (m+n=2) by chemical analysis and slope-fitting methods. The extraction thermodynamic functions were calculated preliminarily, and the results suggested that the extraction process was an exothermic (ΔH <0) and spontaneous (ΔG <0) reaction, and the degree of disorder increased (ΔS >0) during the extraction process. This work will give some guidance to the lithium industry of Qinghai in both the fundamental theory and practical application.展开更多
The organic phase extracted from interfacial crud of copper solvent extraction at Dexing Copper Mine was analyzed for its different components by combined gas chromatography mass spectroscopy. It was found that the ma...The organic phase extracted from interfacial crud of copper solvent extraction at Dexing Copper Mine was analyzed for its different components by combined gas chromatography mass spectroscopy. It was found that the main impurities in organic phase were methylnaphthalenes and di methylnaphthalenes which originated from commercial 260# kerosene used as diluent. It was found that the impurities containing diluent was unfavorable to phase disengagement. Methods were suggested to improve diluent properties to prevent stable interfacial emulsion.展开更多
基金Project(2014CB643401) supported by the National Basic Research Program of ChinaProject(51674294) supported by the National Natural Science Foundation of ChinaProject(2016TP1007) supported by the Hunan Provincial Science and Technology Plan,China
文摘Phase separation rate is a critical character in determining the usefulness of a solvent extraction system in hydrometallurgy. A survey of the synergistic mixture containing dinonylnaphthalene sulfonic acid (HDNNS) and 2-ethylhexly 4-pyridinecarboxylate ester (4PC) for the extraction of cobalt from acidic single metal sulfate solution was carried out to suggest how the physicochemical properties and the morphology of the reverse micelles in the loaded organic phase affect the phase separation. The results show that effective parameters affecting the phase separation are the viscosity and the excess water uptake of the loaded organic phase. It is obvious that the specific settling rate (SSR) decreases with the apparent increase of these two parameters. The measurement of small angle X-ray scattering (SAXS) proves that the morphology of the reversed micelles in the loaded organic phase changes evidently with the change of the specific settling rate (SSR).
文摘A rapid, cost effective and reliable analytical method was developed and validated for the simultaneous determination of four estrogens (17 β-estradiol, 17 α-ethinylestradiol, estrone, and estriol) in compost samples from the biodegradation of biological infectious hazardous wastes. Ultrasonic solvent extraction, using methanol as extraction solvent, coupled with SPE clean-up, using cartridges HLB 60 mg - 6 ml Supelco®<sup></sup> and acetonitrile for reconstitution of eluents, was used for the simultaneous extraction of the four estrogens. Mean recoveries in the range of 98% - 107% were obtained. All compounds were separated in a single gradient run by UHPLC Kinetex<sup>TM</sup> 2.6 μm XB-C18 100 ÅLC (50 × 4.6 mm) column. Analytes were detected via multiple reaction monitoring (MRM) using an AB SCIEX API-5000TM triple quadrupole (Applied Biosystems/MDS SCIEX) with electrospray ionization in negative mode. Isocratic mobile phase of Water:ACN (50:50) resulted to be the optimum. Limits of detection and quantification were on the order of 0.66 ng·g<sup>-1</sup> and 2 ng·g<sup>-1</sup> for all the estrogens. These limits were lower than most of the values reported in the literature for similar matrices. Suitable level of linearity, good repeatability and reproducibility with coefficients of variation is lower than 11.7%, 6.8% and 8.3%, respectively.
文摘Dummy molecularly imprinted polymers （DMIPs） for 4-（methylnitrosamino）-1-（3-pyridyl）-1-butanol （NNAL） were produced using three structural analogues as dummy template molecules. The chosen analogues were 4-（acetymethylamino）-1-（3-pyridyl）-butanol, 4- （methylamino）-1-（3-pyridyl）-1-butanol, and 1-（3-pyridyl）-1,4,-butanediol. The molecular recognition characteristics of the produced polymers were evaluated by X-ray photoelec- tron spectroscopy （XPS） and Fourier transform infrared spectroscopy （FT-IR）. Interactions between NNAL and methacrylic acid should be cooperative hydrogen bonds while the ni- trogen atom of the pyridine ring and the oxygen atom of the nitroso group in NNAL are two of the hydrogen-bond acceptors. It was further demonstrated that DMIP synthesized by 4-（acetymethylamino）-1-（3-pyridyl）-butanol had the best binding performance by XPS and FT-IR. Then dummy molecularly imprinted solid phase extraction （DMISPE） was developed for the determination of the analyte using the hit polymer as the sorbing material. Under optimal conditions, the recovery of NNAL dissolved in standard solution reached 93%. And the investigated polymer exhibited much higher binding of NNAL when nicotine was acted as the competitive molecule. Also the proposed method was applied to the measurement of NNAL spiked in blank urine samples with recoveries ranging from 87.2% to 101.2%.
基金This study is financially supported by the "973" National Basic Research of China (No. 2004CB619206).
文摘The influences of solid particles in leach solution on the formation of the third phase crud during solvent extraction of copper were studied. Analyzed from the point of view of pH value and surface tension, the study results showed that the solid particle is one of the most important contributors for the formation of the third phase crud. During solvent extraction, if the pH value was greater than 2.30, the number of solid particles in the mother solution increased, in which case the possibility of forming the third phase crud could also increase, and the interface tension value might grow in pace with the quantity of the third phase crud.
文摘Using experimental data from a number of pulsed disc and doughnut solvent extraction columns, a unified correla- tion for the prediction of dispersed phase holdup that considers the effects of mass transfer is presented. Pulsed disc and doughnut solvent extraction columns （PDDC） have been used for a range of important applications such as ura- nium extraction and nuclear fuel recycling. Although the dispersed phase holdup in a PDDC has been presented by some researchers, there is still the need to develop a robust correlation that can predict the experimental dispersed phase holdup over a range of operating conditions including the effects of mass transfer direction. In this study, dis- persed phase holdup data from different literature sources for a PDDC were used to refit constants for the correlation presented by Kumar and Hartland lind. Eng. Chem. Res.,27 （1988）,131-138] which did not consider the effect of col- umn geometry. In order to incorporate the characteristic length of the PDDC （i.e. the plate spacing）, the unified cor- relation for holdup proposed by Kumar and Hartland based on data from eight different types of columns [Ind. Eng. Chem. Res.,34 （1995） 3925-3940] was refitted to the PDDC data. New constants have been presented for each hold- up correlation for a PDDC based on regression analysis using published holdup data from PDDCs that cover a range of onerating conditions and nhwical nronerties and consider the direction of mass transfer.
基金Project(2007CB613601) supported by the National Basic Research Program of ChinaProject(NCET-08) supported by Program for New Century Excellent Talents in University, China
文摘Extraction of copper and ammonia from Cu2+-NH3-Cl--H2O solution using laboratorialy synthesized sterically hindered β-diketone(4,4-dimethyl-1-(4-dodecylphenyl)-1,3-pentanedione) was studied.The effects of the copper concentration,the total ammonia concentration,the initial pH in the aqueous phase,the phase ratio,and the temperature on copper extraction ratio and ammonia extraction in loaded organic phase were investigated using this sterically hindered β-diketone.Under the conditions of temperature 25℃,contact time of two phases 30 min,phase ratio 1-1,concentration of copper 3 g/L,concentration of total ammonia 3 mol/L,aqueous pH 8.43,and the concentration of β-diketone in organic phase 20%(volume fraction),ammonia in aqueous phase is much lower to be extracted by organic phase(just 14.5 mg/L),while the extraction rate of copper is 95.09%.
文摘In order to overcome the difficulty in stripping and reduce the equilibrium time in heavy rare earth separation with acidic organophosphorous extractants, the phase transfer catalysis (PTC) technique was introduced to the solvent extraction process, especially applied to the stripping section, which was called phase transfer catalysis stripping (PTCS) process. in the PTCS process, an acidic phosphorous extractant was mixed with another extractant which can transfer hydrogen ion from aqueous phase to organic phase and almost does not extract rare earth ions, so that the stripping efficiency can be improved and the stripping extraction equilibrium be accelerated. The reaction mechanism of the PTCS and the requisite properties for a feasible PTCS catalyst in rare earth extraction were studied. We selected D(2)EHPA as the extractant, Alamine 336 as the PTCS catalyst and mixed rare earth chlorides as the feed to test the PTCS phenomenon. Based on the experimental data, the applicability of PTCS technique in rare earth solvent extraction was discussed.
基金Projects(52034002,U1802253)supported by the National Natural Science Foundation of ChinaProject(2019YFC1908401)supported by the National Technology Support Project of China。
文摘This work investigated the separation of potassium from sodium in alkaline solution using substituted phenol-based extractants.Superior potassium extraction was achieved with 4-tert-butyl-2-(α-methylbenzyl)phenol(t-BAMBP)than 4-sec-butyl-2-(α-methylbenzyl)phenol(BAMBP).The optimum conditions for the extraction were 1 mol/L t-BAMBP,3:1 volumetric phase ratio(O/A),and two extraction stages.After cross-current extraction,the extraction ratio of potassium reached 90.8%.After scrubbing with deionised water at phase ratio of 4:1 and scrubbing stage of 4,a sodium scrubbing efficiency of 88.2%was obtained.After stripping using 1 mol/L H_(2)SO_(4) at phase ratio of 3:1,the stripping efficiency of potassium reached 94.2%.The potassium/sodium(K/Na)concentration ratio increased 14.3 times from 0.15 in the feed solution to 2.3 in the stripping solution.The efficient separation of potassium from sodium in alkaline solution was achieved via solvent extraction with t-BAMBP.
基金National Key Research and Development Program of China(No.2018YFC0604800)National Natural Science Foundation of China(No.U1707601)+1 种基金Science and Technology Major Project of Qinghai Province(2019-GX-A5)West Light Talent Program of Chines Academy of Sciences(Doctor Project,2016)
文摘In this work, problems encountered by tri-butyl phosphate (TBP) in the industrialization of lithium extraction from salt lake brine were discussed in detail. The behavior of N, N-bi-(2-ethylhexyl) acetamide (N523) during lithium extraction was investigated, and its disadvantages were analyzed in the view of practical application. An N523-TBP mixture extraction system was proposed to alleviate or avoid the defects that N523 and TBP met when they were used separately. The optimal composition of this mixture extraction system was determined to be 20%N523-30%TBP-50% kerosene. The effects of brine acidity, Fe/Li molarity ratio, phase ratio and chloride ion concentration on lithium extraction efficiency were discussed. The operation conditions in single-stage extraction were optimized as brine acidity=0.05 mol/L, Fe/Li molarity ratio=1.3, and phase ratio=2. The high concentration of chloride ions in brine was beneficial for the extraction of lithium. The structure of the extracted complex was proposed as (LiFeCl 4 · n N523 · m TBP)·(2- n )N523 ·(2- m )TBP (m+n=2) by chemical analysis and slope-fitting methods. The extraction thermodynamic functions were calculated preliminarily, and the results suggested that the extraction process was an exothermic (ΔH <0) and spontaneous (ΔG <0) reaction, and the degree of disorder increased (ΔS >0) during the extraction process. This work will give some guidance to the lithium industry of Qinghai in both the fundamental theory and practical application.
文摘The organic phase extracted from interfacial crud of copper solvent extraction at Dexing Copper Mine was analyzed for its different components by combined gas chromatography mass spectroscopy. It was found that the main impurities in organic phase were methylnaphthalenes and di methylnaphthalenes which originated from commercial 260# kerosene used as diluent. It was found that the impurities containing diluent was unfavorable to phase disengagement. Methods were suggested to improve diluent properties to prevent stable interfacial emulsion.
