首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
二(2-乙基己基)磷酸萃取L-精氨酸   总被引:4,自引:0,他引:4  
二(乙基己基)磷酸;二(2-乙基己基)磷酸萃取L-精氨酸  相似文献   

2.
考察了二-(2-乙基己基)磷酸(D2EHPA,H2A2)和仲壬基苯氧基取代乙酸(CA100,H2B2)混合体系在HCl介质中对15种镧系元素(除钷)及钇的萃取性能,计算了稀土元素间的分离系数,并比较了混合萃取体系与D2EHPA单独萃取体系对稀土元素的分离能力.研究了D2EHPA-CA100混合体系对镧的协同萃取机理,用斜率法和恒摩尔法探讨了萃取反应方程式,考察了酸度、萃取剂浓度及温度对萃取性能的影响.结果表明:D2EHPA-CA100混合体系对镧系元素的协同效应随原子序数的增加而减弱.在适当的萃取剂配比下,此混合体系对某些稀土元素的分离能力优于D2EHPA,可用于这些稀土元素的分离.D2EHPA-CA100混合体系协同萃取镧的萃合物组成为LaH5A6B2,反应为吸热反应.  相似文献   

3.
二(2—乙基己基)单硫代磷酸萃取铟的研究   总被引:2,自引:1,他引:2  
目前采用二(2-乙基己基)磷酸(D2EHPA)从硫酸溶液中萃取铟在生产上虽获得广泛应用,但反萃取又转入盐酸体系,腐蚀刺激性较强.改用D2EHMTPA萃取铟可能较好,有关这方面的研究至今尚未见报道,本文从硫酸溶液中考察了D2EHMTPA萃取铟的性能,并与D2-EHPA和二(2-乙基己基)二硫代磷酸(D2EHDTPA)作比较,以了解这类萃取剂结构上的差别对萃取铟的影响,这对选择及合成高效能萃取剂分子也是有意义的,还应用斜率法、饱和法确定了萃取平衡反应及萃合物组成,根据IR与NMR探讨了D2EHMTPA萃取铟的机理。  相似文献   

4.
《Analytical letters》2012,45(4):467-480
Abstract

The tenaammetric behavior of di-(2-ethylhexyl)phosphoric acid (D2KHPA) was investigated by non-phase-selective AC polarography. D2EHPA produces in alkali sulfate supporting electrolytes a decrease of the capacitive current in the region of zero-charge potential, as well as a tensammetric peak located between -1.0 and -1.3 V vs. SCE. In the same range, the second harmonic has a characteristic maximum. The pH of the solution and the nature of the cation in the supporting electrolyte affect both the height and the position of the tensammetric peaks. The tensammetric method allows determination of D2EHPA at concentrations ranging from 0.5 to 200 mg/1. Maximum sensitivity is obtained by measuring the second harmonic.  相似文献   

5.
以正十二烷作稀释剂, 研究了二(2-乙基己基)二硫代次膦酸(D2EHDTPA)对HNO3溶液中Am3+和Eu3+的萃取行为. 考察了酸度、 萃取剂及NO3-浓度和皂化度对萃取的影响. 在考察的pH范围(2.5~4.5)内, D2EHDTPA萃取Am3+和Eu3+的分配比(D)随pH值增大而增加; pH=3.65时, 分离因子(SFAm/Eu)值达到最大(4000). 随D2EHDTPA浓度的增加, DAmDEu值均增加. 斜率分析表明, D2EHDTPA萃取Am3+和Eu3+主要形成3:1和2:1型的萃合物. NO3-未直接参与D2EHDTPA对Am3+和Eu3+的萃取反应. D2EHDTPA经NaOH皂化后, 萃取能力显著增强, SFAm/Eu值提高到104量级, 萃取容量约为理论值的60%. 此外, 使用高分辨质谱、 红外光谱和等温微量热滴定方法研究了D2EHDTPA与Eu3+的配位化学行为, 得到了金属离子与配体的组成比、 络合物稳定常数以及配位热力学参数ΔH, ΔS和ΔG值.  相似文献   

6.
The cloud point extraction behaviors of lanthanoids(III) (Ln(III) = La(III), Eu(III) and Lu(III)) with and without di(2-ethylhexyl)phosphoric acid (HDEHP) using Triton X-100 were investigated. It was suggested that the extraction of Ln(III) into the surfactant-rich phase without added chelating agent was caused by the impurities contained in Triton X-100. The extraction percentage more than 91% for all Ln(III) metals was obtained using 3.0 × 10−5 mol dm−3 HDEHP and 2.0% (v/v) Triton X-100. From the equilibrium analysis, it was clarified that Ln(III) was extracted as Ln(DEHP)3 into the surfactant-rich phase. The extraction constant of Ln(III) with HDEHP and 2.0% (v/v) Triton X-100 were also obtained.  相似文献   

7.
A new method is proposed for the extractive Chromatographic separation of antimony. Antimony is extracted from 0.001–0.5M hydrochloric acid by a silica gel column coated with bis (2-ethylhexyl) phosphoric acid stripped with 2–8M hydrochloric, nitric or sulphuric acid, and determined spectrophotometrically at 555 nm as its complex with phenylfluorone. Antimony can thus be separated from a large number of elements, including iron, manganese, copper and thallium. Arsenic, antimony, bismuth and tin can be sequentially separated.  相似文献   

8.
A polymer inclusion membrane (PIM) is reported consisting of 45% (m/m) di(2-ethylhexyl)phosphoric acid (D2EHPA) immobilized in poly(vinyl chloride) (PVC) for use as a solid phase absorbent for selectively extracting Zn(II) from aqueous solutions in the presence of Cd(II), Co(II), Cu(II), Ni(II) and Fe(II). Interference from Fe(III) in the sample is eliminated by precipitation with orthophosphate prior to the extraction of Zn(II). Studies using a dual compartment transport cell have shown that the Zn(II) flux (2.58 × 10−6 mol m−2 s−1) is comparable to that observed for supported liquid membranes. The stoichiometry of the extracted complex is shown to be ZnR2·HR, where R is the D2EHPA anion.  相似文献   

9.
二(2-乙基己基)磷酸对氨基酸的萃取平衡   总被引:3,自引:0,他引:3  
二(2-乙基己基)磷酸对氨基酸的萃取平衡曹汉瑾,王德宝,刘沛妍,吴子生,严忠(东北师范大学化学系,长春,130024)关键词氨基酸,二(2-乙基己基)磷酸,萃取平衡,分配比迄今为止,有关氨基酸溶剂萃取的文献报道还不多[1~3].本实验以二(2-乙基己...  相似文献   

10.
Fullerene black (FB) - a product of electric arc graphite vaporization after extraction of fullerenes - was modified with the di(2-ethylhexyl)phosphoric acid (D2EHPA). The distribution of D2EHPA between FB and aqueous HNO3 solutions has been studied. The effect of HNO3 concentration in the aqueous phase and that of D2EHPA concentration in the sorbent phase on the adsorption of microquantities of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y nitrates from HNO3 solutions by D2EHPA-modified FB are considered. The stoichiometry of the sorbed complexes has been determined by the slope analysis method. The efficiency of lanthanides’ adsorption increases with an increase in the element atomic number. A considerable synergistic effect has been observed upon the addition of the neutral bidentate tetraphenylmethylenediphosphine dioxide ligand to D2EHPA in the sorbent phase.   相似文献   

11.
The liquid–liquid extraction of copper(II) from sulfate medium with di(2-ethylhexyl)phosphoric acid (D2EHPA, HL) at 25°C is studied with the following parameters: pH, concentration of the extractant, and the nature of diluent. The effect of the diluent using polar and nonpolar solvents in the extraction of copper(II) is discussed. The extracted copper(II) species were CuL2 in 1-octanol and methyl isobutyl ketone and CuL2 · 2HL in toluene, carbon tetrachloride, and cyclohexane. The extraction constants are evaluated for different diluents.  相似文献   

12.
在Tl2SO4+Na2SO4+二(2-乙基己基)二硫代磷酸+n-C8H18+水体系中, 测定了0.1-2.0 mol•kg1离子强度范围内Tl 的平衡摩尔浓度。水相中电解质Na2SO4 控制溶液离子强度, 有机相中萃取剂取278.15 K至303.15 K范围内的恒定摩尔浓度。通过外推法和多项式近似得到了不同温度下的标准萃取常数K0,计算了萃取过程的热动力学量。  相似文献   

13.
金谷  张海霞  聂磊  李吉锋 《分析化学》2002,30(3):267-270
报道了一种新型聚合物二 (2 羟基 4 吡啶偶氮苯基 )聚氧乙烯醚 (di(2 hydroxyl 4 pyridineazobenzol)polyethenoxyether,PE·HPAB)的合成及性质 ,并与相应的小分子试剂 4 (2 吡啶偶氮 )间苯二酚 (PAR)比较。结果表明 :PAR进一步缩合为PE·HPAB后 ,性能明显改善 ,表现为 (1)在水和乙醇中溶解度显著提高 ,由PAR的微溶到PE·HPAB的易溶。对其表面张力的测定表明 ,PE·HPAB具有一定的表面活性。 (2 )与金属离子 (如Ni2 + )形成的络合物 ,在水溶液中稳定性增强 ,显色灵敏度提高了一倍。 (3)即使在大量非离子表面活性剂 (如吐温 80 )存在下 ,灵敏度也不降低 ,还有所提高。 (4)在表面活性剂析相萃取中 ,用PE·HPAB作萃取剂能明显改善分离效果 ,其一是在室温下就有很高的萃取率 ,而PAR和它的络合物即使在较高温度时也基本上不被萃取。其二是不象其它一些水溶性小分子 (如对甲酰基苯偶氮变色酸 )和高分子 (如聚乙烯醇缩对甲酰基苯偶氮变色酸 )等易受试剂的结构、物化性质、无机盐和表面活性剂浓度的影响 ,可用于微量甚至痕量组分的分离富集和测定。从而大大拓宽了表面活性剂析相萃取分离方法的应用范围  相似文献   

14.
Fast and selective separation of dimethyl phthalate, diethyl phthalate, dibutyl phthalate, di(2-ethylhexyl)phthalate (DEHP), benzyl butyl phthalate, diisodecyl phthalate, dimethyl adipate, diethyl adipate, di(2-ethylhexyl)adipate, triethyl citrate, tributyl citrate, tributyl acetyl citrate and n-butyl stearate have been developed on thin layers of inorganic ion-exchanger stannic silicate using a mixture of toluene + ethyl acetate (10:1, v/v) as mobile phase. The development distance and time were 12 cm and 25 min, respectively. Quantitative determination of DEHP was made at wavelength 280 nm by Camag TLC Scanner-3. Limit of quantitation for DEHP was 0.50 μg per zone while its limit of detection was 0.05 μg per zone.  相似文献   

15.
The equilibrium data show that indium can be quickly extracted from acidic aqueous solutions by di-(2-ethylhexyl)phosphoric acid in methyl isobutyl ketone. In this polar solvent the species ML3·HL is extracted. The overall extraction constant is higher than that for other tervalent metals. The extraction process can be combined with AAS determination of the indium. The method is fast because stripping is not necessary, and the organic phase can be analysed directly by AAS. Use of a 51 v/v aqueous: organic phase ratio increases the sensitivity. In the pH-range used the method has good selectivity.  相似文献   

16.
本文采用2-乙基己基膦酸单(2-乙基己基)酯(P-507)树脂,使微量稀土元素与钢中的基体元素,铁、钛、钒和钼分离,以 3.0 mol/L盐酸溶液洗脱P-507色层柱上的稀土元素,采用电感耦合等离子体原子光谱法(ICP-AES)同时测定了钢中La、Ce、Pr、Nd、Sm、Y和 Gd 7种微量稀土元素.试样的标准加入回收率99.3%~108%;相对标准偏差小于5%.  相似文献   

17.
用两相充分混合法,在298±1K下研究了HEH[EHP]-正庚烷-1.0mpL·L-1(Na,H)NO3体系中萃取Fe(Ⅲ)的动力学过程。认为界面慢反应为速率控制步骤。  相似文献   

18.
陈展虹  吴成泰 《合成化学》1997,5(1):105-106,104
合成了1,5-二(2-氨基(或硝基)苯氧基)-N-苯基-3-氮杂戊烷。对它们的结构作了元素分析、红外光谱、核磁共振谱及质谱鉴定。  相似文献   

19.
The transport of Tb(III) in dispersion supported liquid membrane(DSLM) with polyvinylidene fluoride membrane(PVDF) as the support and dispersion solution including HCl solution as the stripping solution and di(2-ethylhexyl) phosphoric acid(D2EHPA) dissolved in kerosene as the membrane solution, has been studied. The effects of pH value, initial concentration of Tb(III) and different ionic strength in the feed phase, volume ratio of membrane solution to stripping solution, concentration of HCl solution, conc...  相似文献   

20.
近年来对溶剂革取过程中有机相形成微乳状液的研究正引起人们的重视同,我们曾用付里叶变换红外光谱法研究过钢皂及钾皂2一乙基已基股酸单·2一乙基已基酯(简写为NaA及KA下同)加水形成微乳状液的过程,观察到P二0,P-0-C,P-0-HH-0-H和0-H等基团吸收谱带频率或强度的变化[‘剑.本文进一步对#、销和钾三种碱金属皂化2一乙基已基胁酸单一2一乙基已基酯有机相微乳状液的形成及其红外光谱作深入研究.1实验部分五.1样品的制备问将金属捏、销和钾各置于2一乙基巴基磷酸单一2一乙基已基酯(以HA表示,下同)一正庚烷中加热回流…  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号