LIQUID-LIQUID EXTRACTION OF METAL IONS WITH AMIDO PODANDS

The extraction properties of ami do podands 1 - 3_ have been investigated. The ether dicarboxylic acid diamide i shows a clear preference for the extration of rare earth metal ions Yb(III)-, La(III) and the alkaline-earth metal ions Ca(II), Sr(II) as well. Due to the presence of the carboxylic group the ether dicarboxylic acid monoamide, 2. extracts the ions of the 3d-elements Cu(II), Co(II) and Zn(II), too. High distribution ratios have been obtained mainly for soft and medium-hard transition metal ions with the N-alkyl imino diacetic acid diamide 3_. Under the experimentally chosen conditions, alkali metal ions such as Na(I) and K(I) are practically not extracted by the investigated amido podands.     

LIQUID-LIQUID EXTRACTION STUDIES OF METAL IONS WITH DIAZACROWN AND STRUCTURE ANALOGOUS OPEN-CHAIN COMPOUNOS

1,10-diaze [8]crown-6, their N,N'-dibutyl- and dioctyl-substituted derivatives and the structure analogous open-chein tetreoxedieza slkanee have been synthesized in order to examine the extraction properties for Na⁺, K⁺, Sr²⁺ and Hg²⁺. It wes found, that the extraction of strontium, potassium and sodium picratee with azacrown compounds ie much higher than that with open-chein oxaaze alkanes. 1,10-diaze [18] erown-6 has a good selectivity for the extraction of Sr²⁺ over K⁺ and Na in alkaline solution. In the case of Sr²⁺ the diffarencea between tha various azacrown compounds are email, whereea in the caee of K⁺ and Na the substituted derivativee are better extractante. Theserssulte correspond qualitativsly with tha order of stebility conetantB in protic solvsnts. The extrectebility of N,N'-dioctyl-l, 10-dieze[18]crown-6 for HgCl₂ is very high. Contrerv to the order of stability conetants the uneubetituted conpound do not extract mercury under the choeen experimental condition*. The extraction power of open-chain conpounde ie aleo high and strong Influenced by the alkyl eubatltuente at the nitrogen donor stons,     

SEPARATION OF TAXANE COMPOUNDS BY LIQUID-LIQUID EXTRACTION

Experimental and numerical studies on liquid-liquid extraction of taxane compounds that are extracted from yew needles by solid-liquid extraction are carried out. In the treatment, the materials are classified to three components, and separation of component C from components A and B is discussed. In experiments, distribution coefficients and selectivities of those components are measured with various solvents. Based on the experimental results, numerical simulation of the countercurrent multistage liquid-liquid extraction process for separating the components is carried out with various operating conditions. Then, the fractional countercurrent multistage liquid-liquid extraction process is examined, and the effect of reflux operation on separation performance of the fractional liquid-liquid extraction process is studied. Based on the numerical results, it is found that the fractional countercurrent multistage liquid-liquid extraction with reflux is superior to the other extraction processes for separating taxane compounds.     

SEPARATION OF TAXANE COMPOUNDS BY LIQUID-LIQUID EXTRACTION

Experimental and numerical studies on liquid-liquid extraction of taxane compounds that are extracted from yew needles by solid-liquid extraction are carried out. In the treatment, the materials are classified to three components, and separation of component C from components A and B is discussed. In experiments, distribution coefficients and selectivities of those components are measured with various solvents. Based on the experimental results, numerical simulation of the countercurrent multistage liquid-liquid extraction process for separating the components is carried out with various operating conditions. Then, the fractional countercurrent multistage liquid-liquid extraction process is examined, and the effect of reflux operation on separation performance of the fractional liquid-liquid extraction process is studied. Based on the numerical results, it is found that the fractional countercurrent multistage liquid-liquid extraction with reflux is superior to the other extraction processes for separating taxane compounds.     

EXTRACTION OF METAL IONS WITH DZEHPA FROM MIXED AQUEOUS-ORGANIC MEDIA

Extraction of metal ions from the aqueous-organic solution containing dimethyl formamide(DMF), dimethyl sulfoxide(DMSO) and acetonitrile(AN) was investigated by using di-2-ethylhexyl-phosphoric acid(D2EHPA) as an extractant. The organic phase was a binary solution of D2EHPA and n-hexane, or D2EHPA and toluene, while the polar phase was a three component solution of metal salt, non-aqueous solvent and water. The extracted metal ions were Cr(III), Fe(III), Al, Cu, Ni, Co(II), Mg and Ag.

The extraction behaviors may be explained by the solvation ability of non-aqueous solvents, the decrease in distribution of the extractant and extract into the organic phase, and the interaction between the extractant and non-aqueous solvents due to the dissolution of non-aqueous solvents in the organic phase.     

EXTRACTION OF HEAVY METAL IONS WITH 3-[(DIOCTYLAMINO)METHYL]ALIZARIN

3-[(Dioctylamino)methyl]alizarin (C₈AL), which is endowed with high solubility in nonpolar organic solvents through introduction of dioctylaminomethyl group into the alizarin nucleus was studied for extracting heavy metal ions such as Cu(II), Zn(II), Cd(II), Co(II), Mn(II), and Ni(II), from aqueous solution.Cu(II) was most readily extracted into chlorobenzene at low pH and thus was separated from other metal ions. The metal ions stabilized in alkaline solution in the presence of water-soluble chelating agents were found to be extracted by this, alizarin-type extraction agent into chlorobenzene with the assistance by lipophilic quaternary ammonium salt, Capriquat? (methyltrioctylammonium chloride, Q^?C1^?).The proton dissociation process of CRAL was studied, and the mechanism of these metal extractions was discussed.The separation of Cu(II) and Ni(II) from the mixture with other divalent metal ions was also studied.     

反胶团萃取蛋白质特性的研究

实验将一种阴离子表面活性剂（AOT）和一种阳离子表面活性剂（Aliquat336）分别溶于异辛烷（isooctane）中，构成了两种不同的反胶团体系．通过用两种不同的反胶团溶液萃取六种蛋白质的实验，研究了水相pH值及离子强度对反胶团体系中水含量Wo和蛋白质萃取率影响的规律．实验发现不论哪种反胶团体系，水相pH值对Wo的影响都不大，但pH值却对蛋白质萃取率有很大的影响，对AOT反胶团体系而言，随着pH值的降低，蛋白质的萃取率升高；对Aliquat336反胶团体系而言，随着水相pH值的降低，蛋白质的萃取率下降．随着离子强度的增大，AOT反胶团体系的水含量大幅度地降低；而对Aliquat336体系水含量的影响很小，但水相离子强度对蛋白质萃取率的影响是相同的，随着离子强度的增大，两种体系对蛋白质的萃取率均下降。     

COMPUTER-AIDED GRAPHICS OF LIQUID-LIQUID EXTRACTION

An algorithm has been developed and tested for steady-state liquid-liquid extraction, using rectangular coordinates. It is capable of handling common types of stagewise contact, i.e., single stage extraction, multistage cross-current, and continuous countercurrent multistage extraction. The results depend on the nature of the extraction scheme and the extent of separation desired. While equilibrium data for some systems are stored in its data bank, the present portable computer simulator ( LIQEXT) has the flexibility of reading equilibrium data for other systems, as well as overriding stored data

Both design and rating cases can be performed. In the design mode, i.e., given the feed and solvent rates and the outlet concentration, it calculates the number of stages, the exit stream flow rates, and the concentration profile. In the rating ( or simulation) mode, i.e., given the feed and solvent rates, and the number of stages, it computes the exit streams flow rates and compositions, and the concentration profile. In both cases a graphical output of the concentration profile is produced, either on the screen or on a hard-copy plotter.     

EQUILIBRIUM OF SOLVENT EXTRACTION OF LANTHANIDE IONS WITH DIDODECYLPHOSPHORIC ACID

Measurement of the extraction equilibrium of europium by didodecylphosphoric acid dissolved in toluene diluent vas carried out at 303 K. From vapor-phase osmometry, it was found that the extractant (HR) is apt to diaerize in toluene diluent. It vas clarified that the lanthanide ion (Ln³⁺) is extracted according to the following equation.

The extraction equilibrium constant of the metal vas obtained.

The extraction equilibria of three lanthanide ions, that is, samarium, europium and gadolinium by the extractant from mixed solution of the metals were also measured. The extraction equilibrium constants of respective metals were obtained. The separation factor between samarium and europium vas found to be improved compared vith the extractions by 2-ethyIhexylphosphonic acid mono-2-ethylhexyl ester and di (2-ethylheiyl)phosphoric acid.     

INFLUENCE OF THE NATURE OF METAL IONS ON THE EXTRACTION CONSTANTS OF THEIR DITHIOCARBAMATES

ABSTRACT

It is demonstrated that the electronegativity of metals extracted in the form of diethyldithiocarbamates affects the extraction constants in two ways, namely, through its influence on the chelate stability and the partition constants. The corresponding interrelations can be used to predict extraction constants from any of the following three characteristics: the Klopman electronegativity of the metal, the chelate partition constant, or the chelate stability constant.     

LIQUID-LIQUID EXTRACTION OF METAL IONS BY NEUTRAL PHOSPHOR- AMIDES. PART I,EXTRACTION OF URANYL IONS FROM NITRATE AND SULPHATE MEDIA. EXAMINATION OF EXTRACTED SPECIES BY UV/V1S AND sip NMR SPECTROSCOPY.

ABSTRACT

The extraction of uranyl nitrate and uranyl sulphate from aqueous media by the neutral chelating diphosphoramides CH₃-N[P(OKNMe₂)₂] (NIPA) and its less hydrophilic homologues R-N[P(O)(NMe₂)₂]₂ (R = -C₁₂H₂₅ (OD1PA) or -C₁₆H₃₃ (OHDIPA)), diluted in CH₃NO₂ or toluene, has been studied. In the presei ce of HNO₃, NaNO₃, NaCl, and Na₂SO₄ as salting-out agents, extraction is generally excellent. Some of the extracted complex species have been identified by comparing their ³¹P NMR and UV/vis spectra with those of pure complexes of known structure. The results are compared with extractions using tri-n-butyl phosphate (TBP) as complexing agent.     

LIQUID-LIQUID EXTRACTION OF 2,3-BUTANEDIOL FROM DILUTE AQUEOUS SOLUTIONS WITH MIXED SOLVENTS

Distribution coefficients for the liquid-liquid extraction of 2,3-butanediol (5wt%) in aqueous solutions with binary mixtures of 4-nonylphenol (0-67 vol%), toluene and several alcohols, (2-ethyl-l-hexanol, 1-oclanol and 1-decanol) at 25°C are reported. The distribution coefficients were in the following ranges: 4-nonylphenol + toluene (0-0·23), 4-nonylphenol + 2-ethyl-l-hexanol (0·23 - 0·27), 4-nonylphenol + 1-octanol (0.21-0·33) and 4-nonylphenol + 1-decanol (0·22-0·37). The largest distribution coefficient was found to be 0·37 for the mixed solvent 4-nonylphenol+1-decanol (50vol%), which shows a slight decrease in the separation factor. Activity coefficients at infinite dilution were determined using the MOSCED model and a similar trend for all the solvent mixtures of 4-nonylphenol and alcohols was found.     

HEAVY METAL EXTRACTION WITH THIOCARBAMIC-O-ALKYLESTERS

ABSTRACT

Two types of thiocarbamic-O-alkylesters, four bidentate ligands HL and one bis-bidentate ligand H₂L, were used as extractants for heavy metal ions from aqueous solutions. Silver(I) was extracted as neutral complexes in a yield > 99 %. The underlying stoichiometry and the extraction constants are discussed. The extraction of silver&I) by the bis-bidentate ligand is significantly more effective than the extraction by the analogous bidentate compound. In a dioxane/water mixture neutral, cationic and anionic silver complexes were found by means of pAg and pH potentiometric titrations. The extraction behavior is discussed with regard to the calculated stability constants.     

掺杂金属离子对铁的有机物热解产物的影响及其机理

系统研究了掺杂金属离子对硬脂酸铁热解产物的影响。结果显示：影响热解产物的因素不仅与掺杂离子的半径有关,而且还与其离子的电荷及电子构型有关,即掺杂离子极化力的大小决定热解产物的种类。当掺杂离子的极化力较小时,其对应的硬脂酸盐热解形成的碳酸盐能稳定存在,从而有利于生成γ-Fe2O3;反之则有利于生成α—Fe2O3。通过实验还发现：运用该观点同样可以很好地解释掺杂金属离子对其它铁的有机物热解产物的影响,提出对γ—Fe2O3起稳定作用的主要原因可能在于掺杂金属离子有机物热解形成的、处于γ—Fe2O3晶体表面的CO3^2-。     

COMPLEX FORMATION AND LIQUID-LIQUID EXTRACTION OF SILVER WITH CYCLIC AND OPEN-CHAIN OXATHIA ALKANES

The complex forming and extraction properties of various open-chain and two cyclic oxathia alkanes towards silver have been studied. The investigations confirm the direct proportionality between extraction constants and related complex stability constants.The extraction of silver by open-chain oxethie alkenee is greeter than by structurally analogoue thicacrown compounds. This fact and the determined stability constants show an absence of a macrocyclic effect during complex formation. The differences of extraction power between the various open-chain compounds can be interpreted on the basic o f the coordinative saturation and stereochemiatry of the silver ion, on the size o f the poesible chelate rings, and on the complexing capability o f the ether oxygen atoms.     

THE EXTRACTION OF SOME BASE METAL IONS BY CYANEX 30L CYANEX 302 AND THEIR BINARY EXTRACTANT MIXTURES WITH ALIQUAT 336

ABSTRACT

The extraction behaviour of Cyanex 301, Cyanex 302 and their binary extractant mixtures with Aliquat 33b towards copper(II), zinc(II), iron(III), iron(II), cobalt(II), nickel(II) and manganese(Il) is indicated. The extraction data were collected from sulphate solutions with acidities ranging from pH 10 to 8 mol/dm³ sulphuric acid. Cyanex 301 is a more efficient extractant than Cyanex 302 and is able to effect extraction at greater acidities. In combination with the organic base Aliquat 336 the extraction power of these extractants is lowered and in some cases the extraction is suppressed appreciably. However, the suppression of extraction can be useful in metal separation and affords greater control over the back-extraction. The suppression is ascribed to the high stability of the acid-base couple which must dissociate in order to effect extraction.     

A POSSIBLE USE OF PHOTO-REACTION IN LIQUID-LIQUID EXTRACTION OF SUBSTITUTION-INERT METAL COMPLEXES. EXTRACTION OF CHROMIUM(III) AND COBALT(III) COMPLEXES.

A liquid-liquid extraction of chromium(III) ion was achieved by a cooperative action of light (photoreduction) and conventional extractants on chromium(VI) species. The extraction of chromium spcies was studied by both molecular and atomic absorption spectrophotometry measurements. Trioctylphosphine oxide (TOPO) was the most effective among the extractants studied (TOPO, dibutylsulfoxide, tributyl phosphate, 2-ethyhexyl hydrogen 2-ethylhexylphosphonate, di (2,4,4-trimethylpentyl)-phosphinic acid). A back-extraction of chromium(III) species to aqueous solution was also promoted by photo-irradiation. The nature of the extraction system was studied under various operational conditions such as wavelength of illuminating light, coordinating ah ionic species in aqueous solution, and coexisting metal ions. A liquid- liquid (back-) extraction of some     

NEW XANTHIC ACID DERIVATIVES AS POTENTIAL REAGENTS IN THE SOLVENT EXTRACTION OF PRECIOUS METAL IONS: EXTRACTION OF PALLADIUM(II) WITH 13-BIS(0-BUTYLXANTHATO)PROPANE

ABSTRACT

Two series of new xanthic acid derivatives namely, the bis (O-butylxanthato) alkanes ( abbreviated as BBXAs or simply as bis-xanthates in this paper) have been synthesized in connection with the solvent extraction of precious metal ions. From an aqueous medium containing 0.1 M NaC10₄ (1 M=l mol dm^-3), these compounds exhibited high selectivity for extraction of Pd(II) and Ag(I) in dichloroethane, over most of the base metals as well as Pt(IV) and Au(III) ions. Towards Pd(II) and Ag(I) ions, the bis compounds act as SS chelating agents where the stabilities of the extractable complexes are determined by the length of the alkylene chain existing between the donor atoms. Pd(II) extraction has been studied in detail taking 13-bis(O-n-butylxanthato)propane (BnBXP) as the representative member of the series of bis-xanthates synthesized in this work. The extraction of palladium(II) was found to be quite slow in pure chloride medium. But, a mixed acid medium containing H₂SO₄ or HNO₃ in the presence of smaller amount of chloride ion provided optimum reversible extraction of palladium in dichloroethane, where Pd(II) forms 1:1 extractabic complexes with BnBXP. Pd(II) extraction is described in terms of the aqueous phase compositions, extraction and back-extraction data, extraction equilibrium, selectivity considerations and probable mechanisms of extraction.     

实验室模拟过渡金属离子掺杂的中国古代玻璃的着色现象

为了明确中国古代玻璃的着色机理,根据若干典型的古代玻璃系统(PbO-BaO-SiO_2,K_2O-SiO_2,K_2O-PbO-SiO_2和Na_2O-CaO-SiO_2)的平均化学成分,在实验室于空气气氛中制备了一批掺杂不同过渡金属离子的中国古代玻璃的模拟样品.通过对各样品在室温下的电子顺磁共振、紫外-可见吸收光谱分析,确认了各过渡金属离子在不同古代玻璃系统中的着色离子的价态,以及不同古代玻璃系统对过渡金属离子着色的影响.通过对过渡金属离子掺杂的各古代玻璃系统的吸收光谱进行了色度学的标定.实验表明古代玻璃的着色可以用色度学标定来识别其不同的着色离子和玻璃基质.