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1.
《Analytical letters》2012,45(4):1033-1043
Abstract

A rapid method is proposed for separation of iron(III) with Aliquat 336S as the stationary phase coated on silica gel column with citric acid buffered at pH 4,5 as mobile phase. the extracted iron is stripped from the column with different mineral acids and determined spectrophotracally as its complex with 1,10-phenanthroline, Iron was separated from chromium, molybdenum, titanium and nickel which are generally associated in steel samples. Similar separations of iron from lead, zinc, cadmium, bismuth and cobalt have significance in environmental sample analysis. the method is extended for analysis of iron from samples of sediment and sea-water.  相似文献   

2.
双(十二烷基亚磺酰)乙烷溶剂萃取钯及其机理的研究   总被引:2,自引:0,他引:2  
李焕然  许洪民 《分析化学》1994,22(7):702-705
本文研究用双(十二烷基亚磺酰)乙烷萃取钯的性能,在KI存在下从7mol/L盐酸介质中用含有BDSE的氯仿能定量萃取钯,有机的钯可被硫脲或氨溶液反萃继之用TMK-TritonX-100光度法测定,研究了萃取的最佳条件及干扰情况,斜率法测得萃合物组成为Pd:I:BDSE=1:2:1,红外光谱证实萃合物中BDSE的二个亚砜以硫原子与钯配位,萃合物为异位体络合物,提出了选择性萃取分离钯的新方法。  相似文献   

3.
A liquid-liquid extraction study has been conducted to separate hafnium from zirconium, using Cyanex 301 in kerosene. Noticeably, it is the first time that Cyanex 301 is utilized to separate Hf(IV) from Zr(IV). In this series of experiments, several parameters influencing the separation have been investigated, such as the initial pH, the extractant concentration, the metal ion concentration, the temperature, the type of the diluents and the salt addition. Regarding the aging of the Zr(IV) and Hf(IV) solutions, the solutions with a maximum 3 d aging time could be used with no difficulties. It was observed that the initial pH increase caused an increase in the Zr(IV)/Hf(IV) separation factor. Moreover, the distribution decreased with the temperature increase, suggesting that the reaction is exothermic. In agreement with the resulting data, the optimum separation factor illustrates the value of 7 at a pH of 4.00 in the presence of NaCl as an added salt. The attractive characteristics of the presently designed method are the use of low acidic nitrate solutions, the lack of using thiocyanate and a higher extractability of hafnium-Cyanex 301 relative to zirconium-Cyanex 301 complexes.  相似文献   

4.
溶剂萃取分离碱性氰化液中的金   总被引:11,自引:0,他引:11  
余建民  李奇伟  陈景 《应用化学》2001,18(12):962-0
氰化亚金;碱性氰化液;溶剂萃取分离碱性氰化液中的金  相似文献   

5.
新萃取剂双(正-辛基亚磺酰)乙烷溶剂萃取钯的性能和机理   总被引:3,自引:0,他引:3  
研究在KI存在下用双(正-辛基亚磺酰)乙烷的乙酸丁酯溶液对钯(Ⅱ)的萃取性能。实验结果表明,从pH3至6mol/L盐酸介质中能定量萃取钯(Ⅱ),详细研究最佳萃取与反萃取条件和干扰情况。  相似文献   

6.
Titanium(IV) in sulphuric, perchloric and hydrochloric acid media reacts with 3-hydroxy-2-methyl-1-(4-tolyl)-4-pyridone (HY) to give a complex which is extractable into chloroform. The composition of the extractable complex depends on the acidity of the aqueous phase and on which mineral acid is used. The mixed titanium-perchlorate-HY complex which is formed in the presence of excess of perchlorate is the most suitable for the spectrophotometric determination of titanium. The molar absorptivity of the complex is 1.6×1041·mole–1·cm–1 at 355 nm. The optimum titanium concentration range is 0.5–6,g/ml. The method has been successfully applied to the determination of titanium in samples of bauxite and alumina refractory.  相似文献   

7.
Two new macrocyclic Schiff bases (II) and (III) containing nitrogen ‐ oxygen donor atoms were synthesized by reaction between diethylene triamine or 2,2′‐(ethylenedioxy)bis(ethylamine) and the intermediate compound: 1,4‐bis(6‐methoxy‐2‐formylphenyl)‐1,4‐dioxabutane (I). Identification of these macrocyclic Schiff bases: 1,12, 15,18, 29,32 ‐ hexaaza ‐ [3,4;8,9;20,21;26,27‐tetra‐(6′‐methoxyphenyl)]‐5,8,22,25‐tetraoxa cyclo tetratriacosine‐1,11,18,28‐tetraene. (II) 1,12,21,32‐tetraaza‐[3,4;9,10;23,24;29, 30‐tetra‐(6′‐methoxyphenyl)]‐5,8,15,18,25,28,35,38‐octaoxa cyclo ‐ tetracontane‐1,11,21,31‐tetraene. (III) were determined by elemental analysis (LC‐MS), (IR) and (1H and 13C‐NMR) spectroscopy. The liquid‐liquid extraction of metal picrates such as Ag+ and Cu2+ from aqueous phase to organic phase was carried out using these ligands. The effect of chloroform and dichloromethane as organic solvents over the metal picrate extractions were investigated at 25 ± 0.1 °C by using atomic absorption spectrometer.  相似文献   

8.
The solvent extraction method involving diglycolic acid (dicarboxy methyl ether) as a competitive ligand to lutetium and N-tris[hydroxymethyl]methyl-2-aminoethanesulfonic acid (TES) as a buffer was used to study the hydrolysis of lutetium in 1 mol⋅dm−3 NaCl ionic strength at 303 K. Acid dissociation constants of H2DG and TES were determined and the possible formation of lutetium–TES compounds was investigated. It was found that lutetium does not form compounds with TES under the experimental conditions. The solvent extraction method using 177Lu as a tracer was applied and the first hydrolysis constant of lutetium was determined by means of the relationship of the equilibrium constant of the complex Lu(DG)+ in the absence and in the presence of hydrolysis. The value obtained was log 10 β Lu,H=−7.9±0.3.  相似文献   

9.
《Analytical letters》2012,45(11):737-743
Abstract

A methylisobutyl ketone/formamide two-phase organic solvent system was utilized for the separation of thallium(III) from the elements Ga, In, Fe(III), Sn(II) and Sn(IV). The procedure involves a semi-selective extraction of the elements from an aqueous 2M HBr solution with methylisobutyl ketone followed by the complete separation of thallium from the other elements enumerated by stripping the ketone phase with a 1.5M HBr-formamide solution. Thallium was determined at 3776 Å by flame emission spectrometry.  相似文献   

10.
中钇富铕稀土矿萃取分离流程的经济技术指标比较   总被引:13,自引:1,他引:12  
根据当前国内外市场可预测的产品结构,针对中钇富铕矿为代表的离子吸收型稀土矿,提出了三种可行的P507-HCl体系和环烷酸-HCl体系相结合的稀土萃取全分离工艺流程,比较了各流程的槽体级数的容积,有机相和稀土存槽量,盐酸和液氨消耗以及控制要求等。从经济技术指标角度得到了中钇富铕稀土矿分离的最优化工艺流程,可节省投资5%~50%。  相似文献   

11.
Solvent extraction of copper(II) from sulfate medium with N-(2-hydroxybenzylidene)aniline is studied with the following parameters: pH, concentration of the extractant, nature of diluent, and temperature. The extraction of copper(II) proceeds by a cation exchange mechanism and the extracted species are CuL2 in cyclohexane and toluene and CuL2 with some CuL2HL in chloroform. The equilibrium constants have been calculated as well as thermodynamic parameters ΔH°, ΔS°, and ΔG°. The temperature effect on the solvent extraction of copper(II) with N-(2-hydroxybenzylidene)aniline in cyclohexane is discussed.  相似文献   

12.
Temperature swing solvent extraction (TSSE) utilizes an amine solvent with temperature-dependent water solubility to dissolve water at a lower temperature to concentrate or crystallize the brine and the phases are separated. Then, the water in solvent mixture is heated to reduce water solubility and cause phase separation between the solvent and water. The solvent and de-salted water phases are separated, and the regenerated solvent can be recycled. Issues with current TSSE solvents include the high solvent in water solubility and the high solvent volatility. This project used the highly tunable platform molecule imidazole to create two 1-butylimidazole isomers, specifically 1-propyl-4(5)-methylimidazole, to test their effectiveness for TSSE. The imidazoles take in more water than their current state-of-the-art counterparts, but do not desalinate the product water and dissolve in water at higher concentrations. Thus, while imidazoles make intriguing candidates for TSSE, further work is needed to understand how to design imidazoles that will be useful for TSSE applications.  相似文献   

13.
A novel method has been developed for the solvent extraction of tin(IV) from 8 M hydrochloric acid with 4% N‐n‐octylaniline. Tin(IV) from the organic phase was determined spectrophotometrically with pyrocatechol violet at 550 nm. Extraction was found to be quantitative in the range of 7–10 M hydrochloric acid. When the concentration of N‐n‐octylaniline was varied from 0.05–20% in xylene, it showed that optimum concentration was > 3%. Amongst diluents like benzene and xylene, toluene was found to be an effective diluent. Effect of shaking time, concentration of metal ion, and salting out agents was studied. Tolerance limits of various diverse ions were determined by masking interfering cations. Tin(IV) was separated from associated elements in its binary mixture with Se(IV), Sb(III), Bi(III), Pb(II), Au(III), Cu(II) and Zn(II) and from its ternary mixtures with Sb(III), Bi(III) and Cu(II), Au(III). The proposed method was applied for separation and determination of tin(IV) in tin bearing alloys and foodstuffs.  相似文献   

14.
In developing a method for possible low level isotopic enrichment, which uses to advantage the equilibrium isotope effect observed during U(1V)-U(VI) electron exchange reaction in sulphate solutions, details of a solvent extraction process involving high concentration of a mixture of U(IV) and U(VI) and at low acid concentrations, are described. The extraction behaviour of uranium under these conditions is discussed. During the extraction with amines, U(IV) tended to get oxidised in sulphate solutions.  相似文献   

15.
《Analytical letters》2012,45(5-6):565-573
Abstract

The distribution of Pb(II) between an aqueous phase and a toluene phase containing dehydrated fatty acids found in distilled castor oil (AGDOMD) has been studied. Using the slope technique the conditional equilibrium constant of extraction was determined (kext = 1.02 × 10?7) and the main species present in the organic phase was identified as (PbNO3R. 2HR)(o), where HR represents the fatty acid used.  相似文献   

16.
The article presents data on the solvent extraction separation of rare-earth elements (REEs), such as La(III), Ce(III), Pr(III), and Nd(III), using synergic mixtures of methyltrioctylammonium nitrate (TOMANO3) with tri-n-butyl phosphate (TBP) from weakly acidic nitrate solutions. Specifically, experimental results on separation of REEs, for the pair Ce(III)/Pr(III) for quaternary mixtures of REEs (La(III), Ce(III), Pr(III), Nd(III)) and for the pair La(III)/Pr(III) for solutions containing La(III), Pr(III), and Nd(III), are presented. It was shown that effective separation for the pair Ce(III)/Pr(III) from a solution containing 219 g Ce(III)/L, 106 g La(III)/L, 20 g Pr(III)/L, 55 g Nd(III)/L, and 0.1 mol/L HNO3, was achieved using 56 steps of a multistage, counter-current solvent extraction cascade with scrubbing, at an organic-to-aqueous phase volume ratio (O/A) equal to 2/1 on the extraction section and O/A equal to 4/1 on the scrubbing section, using 3.3 mol/L solutions of the mixture TOMANO3-TBP with molar ratio 0.15:0.85 in dodecane. Separation for the pair La(III)/Pr(III) could be achieved using a solvent extraction cascade with scrubbing in 32 steps at O/A equal to 2/1 on the extraction section and O/A equal to 2.8/1 on the scrubbing section of the solvent extraction cascade from a solution containing 258 g La(III)/L, 58 g Pr(III)/L, 141 g Nd(III)/L, and 0.1 mol/L HNO3 with 3.0 mol/L solution of the mixture TOMANO3-TBP with molar ratio 0.2:0.8 in dodecane.  相似文献   

17.
《Analytical letters》2012,45(1-2):113-121
Abstract

The cation exchange chromatographic behaviour of thallium (I) on Dowex 50W-X8 was carried out in mixed solvents. Nitric, sulphuric, perchloric acid and their salts, as well as in mixtures of 2 M nitric acid with methanol, ethanol, acetone, dioxane and titrahydrofuran, were studied as the eluants. In comparison with other elements, since thallium was weakly sorbed, it was first eluted, while strongly bound elements like manganese, magnesium, cobalt, indium, gallium, zinc, iron, scandium, yttrium, aluminium, calcium, strontium, and barium were subsequently eluted. The best separations were possible from nitric acid in the presence of non-aqueous solvents such as methanol and ethanol.  相似文献   

18.
The essential oils of hinoki (Chamaecyparis obtusa) leaves have anti-bacterial, anti-fungal, and relaxation properties that are likely associated with the major components such as sabinene, α-terpinyl acetate, limonene, elemol, myrcene, and hibaene. The present study describes the use of a cellulose-dissolving ionic liquid (IL) [C2mim][(MeO)(H)PO2] and low-toxicity solvents called betaine-based deep eutectic solvents (DESs) for the efficient extraction of hinoki essential oils. As a control method, organic solvent extraction was performed using either hexane, ethyl acetate (EtOAc), or acetone at 30 °C for 1 h. Both the experimental and control methods were conducted under the same conditions, which relied on partial dissolution of the leaves using the IL and DESs before partitioning the hinoki oils into the organic solvent for analysis. Quantitative analysis was performed using gas chromatography–mass spectrometry (GC-MS) in selected ion monitoring (SIM) mode. The results indicated that extraction using the [C2mim][(MeO)(H)PO2]/acetone bilayer system improved the yields of limonene and hibaene, 1.5- and 1.9-fold, respectively, when compared with the control method. In addition, extraction using betaine/l-lactic acid (molar ratio 1:1) gave the greatest yields for both limonene and hibaene, 1.3-fold and 1.5-fold greater, respectively, than when using an organic solvent. These results demonstrate the effective extraction of essential oils from plant leaves under conditions milder than those needed for the conventional method. The less toxic and environmentally begin DESs for the extraction are also applicable to the food and cosmetic industries.  相似文献   

19.
采用快速溶剂萃取(ASE)技术和高效液相色谱法测定某球形药中叠氮硝胺(DIANP)、硝化甘油(NG)和II号中定剂(C2)的含量.ASE提取条件:二氯甲烷做萃取溶剂,萃取温度100℃,静态萃取10 min,萃取2次.HPLC测定条件:YWG C18柱(150×4.6 mm,10μm),以甲醇和水作为流动相,梯度洗脱,流速1 mL/min,检测波长210nm.测定结果表明DIANP、NG、C2平均回收率分别为99.6%、100.3%、99.4%,RSD分别为0.7%、0.8%、0.9%(n=5),检出限分别为2.1、1.5和0.2 mg/L,线性范围分别为0.02~0.98 g/L,0.03~1.38 g/L,0.002~0.124g/L.用此方法共检测某批球形发射药样品5份,检测结果与滴析-HPLC法检测结果相当.  相似文献   

20.
The electron spin resonance spectra of N-carbamoyl-N-(l-oxyl-2,2,5,5-tetramethyl-pyrrolin-3-yl) urea compounds in ten solvents with different polarities were determined. It was found that the hyperfine splitting constant AN and spin density pN. as well as the energy difference between two adjacent energy levels E of different pyrroline nitroxides in the same solvent increase with the increase of electron-withdrawing α-bility of the substituted groups on the aromatic ring. There was a linear correlation between AN and Reichardt ET value, and between AN and Z value as well. Such a linear correlation was also found between solvent viscosity n and ESR rotational correlation time r. On the other hand, the correlation between T and the relative height hr of peak on high field was reverse. The results are discussed in the paper.  相似文献   

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