伯胺萃取剂合成方法的研究(工作报告)

长碳链脂肪族伯胺是一类具有特殊工艺性能的有机化合物。它被用作缓蚀剂、汽油及喷气机燃料油的抗氧化剂及稳定剂。伯胺的羧酸盐是一类性能良好的表面活性剂。随着原子能科学技术的发展,胺类化合物作为金属萃取剂已有专著论述,它们的合成方法也有综述。叔胺(N235)及季铵盐(N263)萃取剂在我国已是工业化产品。高碳多支链伯胺从硫酸盐溶液中萃取Fe(Ⅲ)、Ce(Ⅳ)、Ti(Ⅳ)、Zr、Th、V(Ⅳ)与稀土元素的性能是很突出的。国外商品Amine21F81(Ⅰ)及Primene JM-T(Ⅱ)可视为伯胺苯取剂的代表。     

伯胺N1923从盐酸溶液中萃取镉(Ⅱ)的机理

伯胺N_(1923)从HCl介质中可以两种机理萃取Cd(Ⅱ),在微酸性溶液中以配位反应萃取Cd(Ⅱ)生成的化合物为(RNH_2)_3CdCl_2;而在酸性溶液中萃取机理为加合反应,萃合物的组成是(RNH_3~+)_3[CdCl_5~(3-)],并计算了两种反应的浓度平衡常数及热力学函数。     

磷酸对伯胺萃取分离稀土(Ⅲ)与铁(Ⅲ)的影响及铁(Ⅲ)的萃取机理

本文研究了磷酸对伯胺N₁₉₂₃从硫酸溶液中萃取分离稀土(Ⅲ)与铁(Ⅲ)的影响,指出了磷酸的存在有利于稀土(Ⅲ)与铁(Ⅲ)的分离。考察了不同结构的伯胺和不同性质的溶剂及温度对萃取平衡的影响。通过IR测定和斜率法等研究,提出了N₁₉₂₃从磷酸介质中萃取铁(Ⅲ)的机理。     

伯胺N1923萃取体系反胶束的形成研究

伯胺 N1 92 3是重要的国产萃取剂 ,其经酸化后生成的铵盐在有机相中可聚集形成反向胶束或微乳液[1] ,但在盐酸和硫氰酸等一元酸介质中萃取金属时 ,萃取剂的聚集现象对萃取机理影响不大 ,可用斜率法分析实验结果 ,确定萃合物组成 [2 ] .而在硫酸介质中却表现出特殊的萃取现象 ,发生胶束萃取[3] .对此 ,本文试图从表面与胶体化学的角度对伯胺萃取体系反胶束的形成作深入研究 ,以期对伯胺萃取体系的萃取机理获得更深入的了解 .1　实验部分1 .1　试剂与仪器　伯胺 N1 92 3( RNH2 ) ,平均分子量 2 91 .8(中国科学院上海有机化学研究所实验厂 ) …     

伯胺N_(1923)从硫酸溶液中萃取稀土元素(Ⅲ)、铁(Ⅲ)和钍(Ⅳ)的机理

本文研究了伯胺N_(1923)萃取H_2SO_4、Ln(Ⅲ)、Fe(Ⅲ)和Th(Ⅳ)的平衡规律。通过分配法、饱和法等的研究及IR测定,提出了不同酸度下H_2SO_4、Ln(Ⅲ)、Fe(Ⅲ)和Th(Ⅳ)的萃取机理。观测了稀土元素(Ⅲ)的萃取率与原子序数的递变规律及钇的位置。     

伯胺N1923从硫酸溶液中萃取稀土元素(Ⅲ)、铁(Ⅲ)和钍(Ⅳ)的机理

本文研究了伯胺N₁₉₂₃萃取H₂SO₄、Ln(Ⅲ)、Fe(Ⅲ)和Th(Ⅳ)的平衡规律。通过分配法、饱和法等的研究及IR测定,提出了不同酸度下H₂SO₄、Ln(Ⅲ)、Fe(Ⅲ)和Th(Ⅳ)的萃取机理。观测了稀土元素(Ⅲ)的萃取率与原子序数的递变规律及钇的位置。     

仲碳伯胺萃取铈(Ⅳ)机理的~1H,~(15)N核磁共振谱研究

仲碳伯胺N_(1923)萃取铈(Ⅳ)的~1H,~(15)N-NMR研究表明,在萃取铈(Ⅳ)时也同时萃取H_2O和H_2SO_4进入有机相,当铈(Ⅳ)浓度较高时,铈(Ⅳ)与N_(1923)生成配合物。     

含氟硫酸介质中伯胺N1923对Ce(Ⅳ)的萃取

铈(Ce)在轻稀土矿物中常与诸如F等多种其它元素伴生,针对矿物处理过程中得到的同时含有Ce(Ⅳ)和F^-等多组分复杂体系硫酸浸出液,从铈氟综合回收并丰富理论依据的角度出发,对伯胺N1923在含氟硫酸介质中Ce(Ⅳ)的萃取及反萃过程进行了研究。考察了酸度、萃取剂浓度、盐析剂浓度及温度对萃取过程的影响,采用斜率法初步讨论了反应机理。研究表明,预先质子化处理后的伯胺N1923在硫酸介质中可同时萃取Ce(Ⅳ)和F^-,H₂SO₄浓度对Ce(Ⅳ)和F^-的萃取过程无显著影响。Ce(Ⅳ)的萃取率随水相中F^-浓度的增加而增大,萃取过程符合加合机理,其萃合物可表示为CeF(SO₄)_1.5(RNH₃·HSO₄)_1.5。通过考察不同温度下N1923对Ce(Ⅳ)的萃取分配比并计算相应的反应平衡常数及热力学参数,表明萃取过程为自发进行的、熵焓双驱动的放热反应。在含氟体系中,体积...     

伯胺N1923萃取乳酸

伯胺 N1 92 3是一种国产仲碳伯胺萃取剂 ,对无机酸、金属配阴离子、小分子有机酸等有良好的萃取性能[1～ 6 ] .文献 [3～ 5]研究伯胺 N1 92 3、TBP萃取醋酸、柠檬酸的平衡 ,文献 [6 ]研究 TRPO萃取乳酸的平衡 .在此基础上 ,本文进一步研究伯胺 N1 92 3萃取乳酸的平衡 ,提出了该类萃取体系的数据处理新方法 .该方法对中性萃取剂萃取小分子有机酸体系的数据处理有普遍意义 .仪器与试剂 :FT-IR5DX红外光谱仪 ,美国NICOL ET公司 ;康氏振荡器 ,山东大学化学学院金工室改装 .伯胺 N1 92 3 ,上海有机化学研究所实验厂产品 ,经减压蒸馏 ( …     

N1923从碱性氰化液中萃取金(Ⅰ)的研究

采用放射性同位素198Au示踪法研究了伯胺N1923和TBP从碱性氰化液中萃取金(Ⅰ),考察了酸化率、水相pH值、萃取剂浓度等对萃取率的影响,以及NaOH对载金有机相的反萃作用。结果表明,TBP含量大于20％,酸化的N1923与KAu(CN)2摩尔比值在11时,金能够完全被萃取。载金有机相可采用0.1mol·L-1的NaOH溶液定量反萃。机理研究表明,伯胺和TBP萃取Au(CN)2-,符合BC类协同萃取机理。当金浓度大于10g·L-1时,在萃取有机相中形成纳米级的聚集体。     

中空纤维膜液相微萃取-高效液相色谱测定有机化合物正辛醇/水分配系数

提出了一种中空纤维膜液相微萃取-高效液相色谱直接测定有机化合物正辛醇/水分配系数的新方法,并用该方法测定了不同脂溶性有机化合物的正辛醇/水分配系数。由于中空纤维膜液相微萃取有机萃取剂用量很少,故能显著提高萃取时的传质速度,缩短萃取时间。正辛醇装入中空纤维膜内,在萃取过程中,正辛醇相和水相不会形成乳化层。萃取完成后,可直接取出正辛醇相的样品进行分析,lgK测定能在30 m in内完成。本研究对6种化合物进行了测定,测定结果用文献报道值和经典摇瓶法进行了验证。表明方法快速、准确、样品消耗量少。     

Monitoring the elimination of gadolinium-based pharmaceuticals. Cloud point preconcentration and spectrophotometric determination of Gd(III)-2-(3,5-dichloro-2-pyridylazo)-5-dimethylaminophenol in urine

An extraction methodology based on cloud point phase separation of non-ionic surfactants has been developed for the preconcentration of ppb amounts of gadolinium in urine as a prior step to its determination by an absorptiometric procedure. A method based on the formation of complexes with 2-(3,5-dichloro-2-pyridylazo)-5-dimethylaminophenol was used for the extraction of Gd(III) in the surfactant-rich phase of non-ionic surfactant polyethyleneglycolmono-p-nonylphenylether (PONPE 7.5). The variables affecting the combined preconcentration-absorptiometric method have been evaluated and optimised. The extraction efficiency, linearity, and the limit of detection (LOD) of the method were determined. The optimised procedure was applied to determine total and free Gd(III) contents in real urine samples of patients after the NMR imaging diagnostic examination with contrast agent.     

Liquid phase microextraction‐ion exchange‐high performance thin layer chromatography for the preconcentration,separation, and determination of plasticizers in aqueous samples

Liquid phase microextraction combined with ion‐exchange‐high performance thin layer chromatography has been developed for analysis of four plasticizers in aqueous samples. After their preconcentration by liquid phase microextraction, fast separation on thin layers of inorganic ion‐exchanger stannic silicate has been developed using a mixture of toluene + ethyl acetate (10:1, v/v) as mobile phase. Consequently, densitometric quantitative determination of the plasticizers has been made at λ = 280 nm in reflection–absorption mode by Camag TLC scanner‐3. The effects of type and volume of extraction solvent, stirring rate, extraction time, and ionic strength in the microextraction method have been also evaluated and optimized. The results show that the proposed method provides enhanced accuracy, linear range, LOD, and LOQ, and is very effective for analyzing the target compounds in water samples. Under the optimized conditions, preconcentration factor of 149–279 and extraction efficiency of 31–59% have been obtained. Repeatability (5.67–7.26%) and intermediate precision (6.21–8.17%) were in acceptable range. The relative recovery obtained for each analyte in different water samples was higher than 82.3% at three fortification levels with RSD <7.9%.     

Extraction of uranium(VI) and thorium(IV) from nitric acid solution by N-alkylcaprolactam

Extraction of uranium(VI), thorium(IV) from nitric acid has been studied with N-octylcaprolactam and N-(2-ethyl)hexylcaprolactam. Distribution coefficients of U(VI), Th(IV) and HNO₃ as a function of aqueous NHO₃ concentration, extractant concentration and temperature have been studied. The compositions of extracted species, thermodynamic parameters of extraction have been evaluated. Third phase formation in extraction of U(VI) has been studied. Back extraction behavior of U(VI) and Th(IV) from the organic phase has also been tested. The results obtained are compared with those obtained by using TBP under the same experimental conditions.     

Synergistic solvent extraction of lutetium(III). Computer aided analysis

Synergism in the extraction of Lu(III) from thiocyanate solutions has been investigated using mixtures of bis-2-ethylhexyl sulfoxide (B2EHSO) and 2-thenoyltrifluoroacetone (HTTA) or di-n-octyl sulfoxide (DOSO) or tri-n-octylphosphine oxide (TOPO) in benzene. For comparison, the synergistic extraction of Lu(III) from perchlorate solutions has also been investigated with a mixture of B2EHSO and HTTA. These extraction data have been analyzed theoretically with the aid of a computer by taking into account complexation of the metal in the aqueous phase by inorganic ligands and plausible complexation in the organic phase. The equilibrium constants of the various product species have been deduced by non-linear regression analysis.     

Thermodynamic Approach of Uranium(VI) Extraction by N,N-(2–ethylhexyl)Isobutyramide

The study of extraction of U(VI) from LiNO3 media by N,N-(2-ethylhexyl)isobutyramide (DEHiBA) in dodecane has been performed at 25.00 °C using isothermal titration microcalorimetry. The raw heat measured is a sum of contributions. To obtain the net extraction enthalpy variation, different heats have to be evaluated as the dilution of amide into dodecane phase which has been measured and subtracted. The microcalorimetric extraction results are then compared to data obtained by Van’t Hoff classical method. The extraction enthalpies obtained by both methods are similar. This first study allowed to define the experimental calorimetric conditions and will be followed by determination with other actinides and amides.     

固相微萃取与色谱联用方法分析水中12种有机氯化合物

运用顶空固相微萃取与色谱闻用方法（ＨＳ－ＳＰＭＥ－ＧＣ）对水中的残留有机氯化合物进行了分析。对影响ＨＳ－ＳＰＭＥ－ＧＣ分析灵敏度的各种实验因素如涂层种类,萃取温度、平衡时间,离子浓度等进行了讨论并将该方法与固相萃取法（ＳＰＥ）,液液萃取法（ＬＬＥ）作了对比,同时考察了常见环境共存污染物直链烷基苯磺酸钠（ＬＡＳ）对几种方法的影响。     

Extraction of some transition metals with N,N-dibutyl-N'-benzoylthiourea into molten paraffin at 65 degrees C

The solid-liquid extraction behaviour of some transition metals (Cu(II), Co(II), Ni(II), Cd(II) and Pb(II)) by the use of N,N-dibutyl-N'-benzoylthiourea as an extractant in paraffin (58-60 degrees C) has been investigated at 65.0+/-0.5 degrees C. The effect of equilibration time, pH of the aqueous phase, concentration of extractant and solid solvent used on the extraction efficiency of these metals have been discussed. The interferences of various ions are examined. The method has been applied to the determination of these metals in synthetic samples, mushrooms and sediment.     

Metal chelate exchange in the organic phase-I Theory: application in spectrophotometry and complex chemistry

Metal chelates, extracted from an aqueous phase by organic solvents, can react with other chelating agents (or their metal chelates) dissolved in the same solvent. This exchange of metal chelates in the organic phase can be used for (1) investigation of the exchange equilibrium and composition of the metal chelates formed, (2) determination of the extraction constants, (3) preparation of new inner-complexes soluble in organic solvents, and (4) spectrophotometric determination of small amounts of metals. The theory and experimental verification of this phenomenon are given. The extraction constants of silver and zinc diethyldithiocarbamates in carbon tetrachloride have been determined by means of the extraction constants of the corresponding dithizonates. A mixed complex of arsenic(III) with dithizone and diethyldithiocarbamic acid has been prepared and its properties studied. A simple method for spectrophotometric determination of microgram quantities of arsenic is proposed.     

Effect of temperature on the stability constants of chloro complexes of actinyl ions

Stability constants of chloride complexes of U(VI), Np(VI) and Pu(VI) have been determined by the method of extraction chromatography at an ionic strength of 2.0 and [H⁺]=2.0M. Dilute HDEHP has been used as the stationary phase.