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1.
《分离科学与技术》2012,47(10):1541-1554
Hollow fiber contactor was used to study non-dispersive extraction (NDSX) of Nd3+ ions from aqueous solutions. N,N,N′,N′-tetraoctyl diglycolamide (TODGA) diluted with n-dodecane was used as the organic phase with di-n-hexyl octanamide (DHOA) as the phase modifier. The role of cations (H+/Na+) on the transport of Nd3+ ions has been investigated for this system. It was observed that H+ ion has a significant role to play in the Nd3+/TODGA complexation reaction. A mathematical model has also been developed to simulate the NDSX process in a hollow fiber contactor. A comparison has also been made between extraction profiles from the NDSX process and the hollow fiber supported liquid membrane (HFSLM) process. It was observed that NDSX gave comparatively faster rates of extraction in the presence of H+ ions but slower in the absence of H+ ions.  相似文献   

2.
分了C:7H。。一e一NH一CH:CH:一NH一C一Ci:Ha。 C:.H,eN,O: 分子量593 l英文名IN,N‘一Ethylene bis(s-tearanl记e) l国外商品名1 Chemetronwa、一100(Chemetron);Armowax EBS(Armak)书H佣ehst WaxC(Hoechst);AerawaxC(Glyeo),Kemam溉w 20(枷mko);Lubro/EA(ICI)。 l性状】白色至淡黄色粉末或粒状物。熔点130一145℃,闪点约285℃,比重0.98。不溶于水,常温下不溶于乙醇、丙酮等大多数溶剂,可溶于混合二甲苯、菇烯、丁醇、甲基溶纤素及大多数氯代烃类。游离脂肪酸含量低于4%,水份低于。.5%。 【制法】乙撑双硬脂酞胺的制备是…  相似文献   

3.
Several analytical methods were evaluated for determining the concentration of N,N’,N”-tris(3,7-dimethyloctyl)guanidine (TiDG) in a cesium extraction solvent. Of the methods evaluated, non-aqueous titration and 1H NMR were shown to be successful at quantifying the amount of TiDG present in both a pure solvent extraction system, and a blended system containing an additional base, trioctylamine.  相似文献   

4.
ABSTRACT

N,N,N’,N’-tetraethyldiglycolamide (TEDGA) is used in the French EXAm (extraction of americium) process to separate Am(III) from Cm(III) and Ln(III). In this study, the complexation behavior of TEDGA towards actinides(III) and lanthanides(III) was compared to its methyl-substituted derivatives Me-TEDGA and Me2-TEDGA under experimental conditions applying to the EXAm process. Using the EXAm solvent, 0.6 mol/L N,N’-dimethyl-N,N’-dioctyl-hexylethoxymalonamide (DMDOHEMA) and 0.45 mol/L bis(2-ethylhexyl)-phosphoric acid (HDEHP), An(III) and Ln(III) distribution ratios increase in the order TEDGA < Me-TEDGA < Me2-TEDGA. This is explained by differences in the strength of complexation in the aqueous phase: Conditional stability constants for the formation of [Cm(DGA)x]3+ complexes decrease in the order TEDGA > Me-TEDGA > Me2-TEDGA, as shown by time-resolved laser fluorescence spectroscopy (TRLFS). TRLFS measurements verified the exclusive existence of [Cm(DGA)3]3+ complexes in the aqueous phase. Both the homoleptic [Cm(DMDOHEMA)n]3+ and the heteroleptic [Cm(DGA)x(DMDOHEMA)y]3+ complexes were detected in the organic phase, as postulated in the literature.[14]  相似文献   

5.
合成了新型萃取剂N,N,N′,N′-四丁基丁二酰胺(TBSA),研究了其萃取Ce(Ⅲ)的性能,详细考察了硝酸浓度、萃取剂浓度、硝酸锂浓度以及温度等对萃取分配比的影响,得出了TBSA以甲苯为稀释剂时萃取反应的表观平衡常数为(0.29±0.16)L6/mol6及298K时的热力学焓变为-17.90kJ/mol,并用红外光谱表征了配合物Ce(NO3)3.3TBSA的结构。  相似文献   

6.
利用乙二胺和丙烯腈的亲核加成反应合成了一种新型有机多腈N,N,N’,N’-四(2-氰基乙基)乙二胺。在Raney Ni存在下对N,N,N’N’-四(2-氰基乙基)乙二胺进行催化加氢,得到N,N,N’N’-四(3-氨基丙基)乙二胺。并用红外、核磁、质谱等对N,N,N’N’-四(3-氨基丙基)乙二胺进行了表征,结果表明所合成的化合物即为标题化合物。  相似文献   

7.
Summary When incorporated into a polymer hydrogel, the metal chelator, N,N,N,N-tetrakis(2-hydroxypropyl)ethylenediamine (THPED), retains its metal binding properties. The resultant poly(THPED methacrylate) homopolymer is a polybase with displacement binding constants for copper (II) and zinc(II) of-3.11 and-6.55, respectively, as compared to values for THPED of-3.83 and-7.44. The chelating capacity of the polymer for various divalent metal ions at pH 5.5 follows the order Cu>Cd>Co>Zn>Mn, while calcium and magnesium do not bind. Metal ion release curves indicate that after 30 hours, Cd(II), Co(II), Zn(II), and Mn(II) are released at a slow, steady rate, while Cu(II) is not released under experimental conditions.  相似文献   

8.
标题化合物("552")是一种新型的粉末涂料固化剂,具有高效、节能、环保的特性.用己二酸二甲酯和二乙醇胺的氨解反应,二步法合成"552",产率86%.具体的条件为:1)n(己二酸二甲酯)∶n(二乙醇胺)=1∶1.1,在甲醇钠和氢氧化钾的催化下,100 ℃反应3 h;2)继续加入二乙醇胺(与己二酸二甲酯的物质的量比为0.95)和甲醇钠,70 ℃反应3 h;总的物质的量比n(己二酸二甲酯)∶n(二乙醇胺)=1∶2.05.探索该反应的过程,分离提纯出中间体并进行 1HNMR 表征,为提高"552"的产率提供理论依据.  相似文献   

9.
甲基丙烯酸(N,N—二甲基氨基)乙酯(简称DMA)是具有聚合性乙烯基及叔氨基的反应性单体。一、DMA的物性 DMA的结构式如下所示,其一般物  相似文献   

10.
间(N,N-二甲胺基)苯甲酸是重要的生化试剂间羧基二甲胺基碘乙烷季铵盐的前体化合物,目前国内尚无商品出售。文献中报道的合成路线有两条。一是,将间氨基苯甲酸在碱性条件下(如氢氧化钠或碳酸钠)与过量硫酸二甲酯反应,生成间(N,N-二甲胺基)苯甲酸甲酯,与氨水在140℃的封管中水解,再用酸中和。二是,将间氨基苯甲酸与甲醛在10%  相似文献   

11.
N,N′-二(缩水甘油醚)-O-甲苯胺,简称 GOT,结构式为(?)鉴于其化学结构是一种芳香族胺的缩水甘油胺,因此,GOT 是一类特殊结构的环氧树脂,在酸、酸酐、多胺、聚酰胺、多元酚等固化剂中,常温或加热固化,便能得到具有优良机械性能、电性能的树脂。GOT 本身又能作其他环氧树脂的稀释剂,特别适宜作  相似文献   

12.
刘涛  丰平 《江苏陶瓷》2005,38(6):20-23
介绍了Ti(C,N)基金属陶瓷的基本组成和结构,综述了Ti(C,N)基金属陶瓷的研究现状,指出了未来的发展方向和应用。  相似文献   

13.
N,N,N-三(2-甲基苯并咪唑)胺的新合成方法   总被引:3,自引:0,他引:3  
以乙二醇为溶剂,由氨三乙酸与邻苯二胺反应,制得N,N,N-(2-甲基苯并咪唑)胺。此合成方法产率高,操作容易控制,污染小。  相似文献   

14.
孔迎刚  陈志  崔玉 《山东化工》2012,41(4):25-28
在两种稀释剂体系中研究了N,N,N’,N’-四丁基-3-氧戊二酰胺(TBOPDA)从盐酸介质中萃取铁离子的性能和反应机理。考察了水相盐酸浓度、萃取剂浓度及温度对其萃取性能的影响。实验结果表明分配比随盐酸浓度的增加而增加;随萃取剂浓度的增加而增大;萃取过程为放热过程,升高温度不利于萃取。  相似文献   

15.
Abstract

The extraction of actinides, fission products, some non-nuclear elements, and nitric acid by N,N,N′,N′-tetraoctyl-3,6-dioxaoctanediamide (DOODA-C8) in dodecane was extensively studied. Also studied was the extraction of HNO3 and Nd(III) by the tetradodecyl analog of DOODA-C8 in dodecane. Both extractants contain two ether oxygen atoms in the backbone chain carrying the two amide groups and can thus act as tetradentate ligands. The extractability of actinides decreases in the order Pu(IV) > U(VI), Am(III) > Np(V) in the extraction from nitric acid and Pu(IV) > Am(III) >> U(VI) in the extraction from perchloric acid. Ions of di-, tri-, tetra-, hexa-, and heptavalent metals strongly differ in the extractability by DOODA-C8 but, except for lanthanides(III), there is no visible correlation of their distribution ratios with ionic radii. Due to the efficient extraction of actinides, weak extraction of fission products, and sufficient extraction capacity, DOODA-C8 is a promising extractant for the recovery of minor actinides from high-level radioactive wastes.  相似文献   

16.
杨建洲  郭义  李华锋 《精细化工》2007,24(3):287-289,298
采用活性环氧中间体失水甘油基三甲基氯化铵合成了一种阳离子双酯表面活性剂——N,N,N-三甲基-2,3-二(硬脂酰氧基)丙基氯化铵(CDESA),来代替传统的难降解的表面活性剂型柔软剂,如目前国内仍在大量使用的双十八烷基二甲基氯化铵(D1821)。对CDESA的好氧降解性能进行了研究:以天然环境中的生活沉降污泥作为微生物源,用河水稀释,经培养、驯化后用于测试降解时间和半衰期,并与D1821的好氧降解性能作了对比。结果表明,CDESA的半衰期为3 d,容易降解,而D1821半衰期为7 d,较难降解,CDESA生物降解性能优于D1821。  相似文献   

17.
N,N′-双(3-甲基苯基)-N,N′-二苯基联苯胺的合成   总被引:3,自引:0,他引:3  
聂海  唐先忠  李元勋 《精细化工》2003,20(9):522-523
以二苯胺为起始原料,经两步反应合成了有机电致发光材料N,N′ 双(3 甲基苯基) N,N′ 二苯基联苯胺(TPD)。通过优化实验得到最佳的合成工艺为:二苯胺在20℃下,以V(冰醋酸)∶V(水)=1∶4为溶剂,加入重铬酸钾进行反应得N,N′ 二苯基联苯胺,分离提纯后,再加入18 冠 6相转移催化剂,以邻二氯苯为溶剂在氮气保护下与间碘甲苯进行乌尔曼反应,在200℃下反应20h,产物经柱层析和重结晶提纯。TPD收率为85%,较文献提高5%,w(TPD)=99 92%。并用元素分析、红外光谱和核磁共振对产物的结构进行了表征。  相似文献   

18.
The extraction behavior of rare earth (RE) elements from thiocyanate medium by N,N,N,N-tetra(2-ethylhexyl) diglycolamide (TEHDGA), a neutral extractant, has been investigated and the optimum conditions for their separations were determined. Isodecyl alcohol was used as phase modifier and a concentration of 5%(v/v) was found sufficient to mitigate third phase formation under our experimental conditions. The extraction mechanism of RE with TEHDGA was established by analyzing distribution data with slope analysis technique and showed the formation of a neutral species, RE(SCN)3.2TEHDGA, in the organic phase. The extraction of rare earth decreased with increase in temperature indicating exothermic nature and the enthalpy change (ΔH) obtained for Y(III) was ?14.27 kJ/mol. Among various stripping agents studied, oxalic acid was found to be efficient in quantitative stripping of rare earths from TEHDGA. The extraction efficiency for all the rare earths by TEHDGA was also investigated. High separation factor of 6.4 for Er/Y pair at 0.03 M thiocyanate has indicated the feasibility of using TEHDGA as extractant to separate Y from heavy rare earths, in particular Er, from thiocyanate medium.  相似文献   

19.
《分离科学与技术》2012,47(6):965-971
The extraction properties of N,N,N′,N′-tetra(2-ethylhexyl)thiodiglycolamide T(2EH)TDGA have been evaluated for the separation and recovery of palladium from simulated high-level liquid waste (SHLW). T(2EH)TDGA has shown very high selectivity for Pd (II) over other metal ions present in SHLW. The separation factor (SF) for Pd (II) over other metal ions was found to be more than 105. Reusability studies of the extractant indicate that DPd remained almost constant even after five successive cycles of extraction and stripping. Palladium was quantitatively recovered from thiourea strip solution by treating it with ammonia and filtering the precipitate of palladium sulphide. The acid uptake constant (KH) was found to be 0.62 which could be due to the presence of two carbonyl groups of amidic moiety. To account for very high extractability of palladium with T(2EH)TDGA over other ‘S’ donor extractants, namely Bis-(2-ethylhexyl)sulphoxide (BESO), FTIR, as well as Raman studies were carried out. FTIR and Raman studies suggested the ligation through carbonyl as well as the thio-ether group. Conditional extraction constants (log K′ex) were determined and the thermodynamic parameters were calculated from the dependence of the conditional extraction constant (log K′ex) on temperature. The calculated values of ΔGex, ΔHex, and ΔSex were ?41.78 kJmol?1, ?55.12 kJmol?1 and ?44.04 JK?1 mol?1 respectively. The extraction process is indicated to be enthalpy driven with the entropy factor counteracting it.  相似文献   

20.
谢福佳  方志杰 《生物化工》2022,(1):92-94,110
N,N,N',N'-四(β-羟丙基)己二酰胺(简称"1260")是一种新型的粉末涂料固化剂,其性能优于N,N,N',N'-四(β-羟乙基)己二酰胺(简称"552").用己二酸二甲酯和二异丙醇胺一步反应合成"1260",反应转化率100%,反应纯度80.6%.本文设计正交试验,通过HPLC检测研究了温度、投料比、催化剂用...  相似文献   

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