Amberlite LA-2 Research Articles

Use of high molecular weight amines for end-point indication in the complexometric titration of Iron(III) with thiocyanate as indicator

A new type of end-point indication for the complexometric titration of iron(III) is proposed. A 10% carbon tetrachloride solution of Amberlite LA-1 is applied for the extraction of the thiocyanate complexes. Very sharp color change of the organic phase from red to pale yellow gives the accurate end point for titrations with 0.01M EDTA as in the Variamine Blue B method.

Ionic peremability of thin lipid membranes. Effects of n-alkyl alcohols, polyvalent cations, and a secondary amine.

Ultrathin (black) lipid membranes were made from sheep red cell lipids dissolved in n-decane. The presence of aliphatic alcohols in the aqueous solutions bathing these membranes produced reversible changes in the ionic permeability, but not the osomotic permeability. Heptanol (8 mM), for example, caused the membrane resistance (R(m)) to decrease from >10(8) to about 10(5) ohm-cm(2) and caused a marked increase in the permeability to cations, especially potassium. In terms of ionic transference numbers, deduced from measurements of the membrane potential at zero current, T(cat)/T(Cl) increased from about 6 to 21 and T(K)/T(Na) increased from about 3 to 21. The addition of long-chain (C(8)ndash;C(10)) alcohols to the lipid solutions from which membranes were made produced similar effects on the ionic permeability. A plot of log R(m) vs. log alcohol concentration was linear over the range of maximum change in R(m), and the slope was -3 to -5 for C(2) through C(7) alcohols, suggesting that a complex of several alcohol molecules is responsible for the increase in ionic permeability. Membrane permselectivity changed from cationic to anionic when thorium or ferric iron (10(-4)M) was present in the aqueous phase or when a secondary amine (Amberlite LA-2) was added to the lipid solutions from which membranes were made. When membranes containing the secondary amine were exposed to heptanol, R(m) became very low (10(3)-10(4) ohm-cm(2)) and the membranes became perfectly anion-selective, developing chloride diffusion potentials up to 150 mv.

Electric conductivity of liquid ion exchangers

Electric conductivities of chloroform solutions of di-(2-ethylhexyl) hydrogen phosphate and bisulphates and hydrochlorides of two secondary long-chain amines Amberlite LA1 and LA2 were measured. All these liquid ion exchangers appear to be dissociated in chloroform and behave like weak electrolytes. No micelle aggregation occurs in the organic phase. This was confirmed by refractive index measurements. Minima visible on some conductivity curves indicate formation of ionic pairs and triplets. Amine bisulphates are stronger electrolytes than amine hydrochlorides.

Infrared spectrophotometric determination of sodium lauryl sulfate by the use of high molecular weight amine

Although sodium lauryl sulfate is little soluble in organic solvents for IR determination, high molecular weight amine is attempted to utilize for the solvent extraction method and employment has been found to be applicable as a new determination method by solution method. A quantitative extraction with 5% CS2 solution of Amberlite LA-2 is found to be capable, followed by the determination at 1194cm-1 as a key band. By this method, even if sodium chloride, sodium sulfate and Tween 40 are present in an equivalent amount to sodium lauryl sulfate, they will not interfere with the determination, and in the case of coexistence of sodium lauryl benzene sulfonate, both components are determined quantitatively at 1250cm-1 and 1164cm-1, key bands, respectively as a binary system.

Infrared spectrophotometric analysis of some water soluble mono- and di-thiophosphoric acid esters by the use of high molecular weight amine

An attempt was made to apply the solvent extraction methods by using high molecular weight amine to the IR analysis of water soluble mono-and di-thiophosphoric acid ester. Both O, O-dimethylthiophosphoric acid and O, O-dimethyldithiophosphoric acid are found to be effective for the qualitative analysis, being extractable with 5% of CS2 solution of Amberlite LA-2, and the latter O, O-dimethyldithio compound is found to be applicable also as a quantitative method. As to "Sumithion" and "Malathion", one of the effective organophosphoric insecticides, solvent extraction was carried out with the hydrolyzed water solution and the presence of O, O-dimethylthiophosphoric acid and O, O-dimethyldithiophosphoric acid have been identified.This method has been proved to be applicable to the investigations of hydrolytic mechanism and partial structures of thiophsphoric acid ester series of insecticides.

Changes to Plutonium Extraction Behavior of TBP and Alkylamines through Irradiation

Changes to plutonium extraction properties brought about through irradiation of 30v/o TBP (Tri-n-butyl phosphate)/kerosene and 5v/o alkylamines/kerosene modified with lauryl alcohol were studied in such respects as extraction, scrubbing and stripping characteristics in nitrate media. The alkylamines examined were tri-n-octyl amine (TOA), N-cyclohexyl dilauryl amine (N-CHDLA) and Amberlite LA-2 (LA-2). These extractante were irradiated to the extent of 108R by 60Co γ-ray, prior to extraction. Marked changes with irradiation were observed in plutonium extraction performance with the TBP system tending to bring losses of plutonium, but very little change was found to occur with amine systems. Calculation of the single stage decontamination factors of fission products from plutonium proved that separation deteriorated with irradiation in the TBP system but hardly changed in the amine systems. From these findings, tertiary amines, especially N-CHDLA, can be judged superior to TBP for the direct recovery of plutonium from irradiated fuels, a process that has to be carried out under high irradiation. The phase separation time after mixing in the extraction stage varied very little with irradiation, and no formation of emulsion occurred in the extraction of tracer plutonium with either irradiated TBP or amines.

Changes to Plutonium Extraction Behavior of TBP and Alkylamines through Irradiation

Changes to plutonium extraction properties brought about through irradiation of 30v/o TBP (Tri-n-butyl phosphate)/kerosene and 5v/o alkylamines/kerosene modified with lauryl alcohol were studied in such respects as extraction, scrubbing and stripping characteristics in nitrate media. The alkylamines examined were tri-n-octyl amine (TOA), N-cyclohexyl dilauryl amine (N-CHDLA) and Amberlite LA-2 (LA-2). These extractante were irradiated to the extent of 108R by 60Co γ-ray, prior to extraction. Marked changes with irradiation were observed in plutonium extraction performance with the TBP system tending to bring losses of plutonium, but very little change was found to occur with amine systems. Calculation of the single stage decontamination factors of fission products from plutonium proved that separation deteriorated with irradiation in the TBP system but hardly changed in the amine systems. From these findings, tertiary amines, especially N-CHDLA, can be judged superior to TBP for the direct recovery of plutonium from irradiated fuels, a process that has to be carried out under high irradiation. The phase separation time after mixing in the extraction stage varied very little with irradiation, and no formation of emulsion occurred in the extraction of tracer plutonium with either irradiated TBP or amines.

Radiation Damage to Amine Extractants, (II)

Radiation damage to 5 v/0 alkyl amine/kerosene modified with lauryl alcohol was studied for changes brought thereby in their behavior in Th and Pa extraction by scrubbing with 3N nitric acid, and stripping with 0.01 N nitric acid at 25°C. Eight amines were used; Tri-n-octyl amine, N-cyclohexyl dilauryl amine, N-benzyl dilauryl amine, N-cyclohexyl lauryl amine, Dilauryl amine, Amberlite LA-1, Amberlite LA-2 and Primene JM-T. These solvents were used virgin as well as irradiated by 60Co γ-ray to various doses up to 108R. No marked changes in extraction-scrubbing-stripping behavior were observed in all the amines tested, except N-cyclohexyl lauryl amine and Dilauryl amine, which tended to form either third phase or emulsion.

Complexes formed between the platinum metals and halide ions. Part 2.—Extraction of haloplatinates by solutions of salts of amberlite LA-2 in carbon tetrachloride and in cyclohexane

The first page of this article is displayed as the abstract.

CONJUGATED OESTROGENS. I

ABSTRACT A convenient and mild procedure is described in this paper whereby free and conjugated oestrogens may be extracted from urine. The extracts containing approximately 90 per cent of the oestrogens are devoid of most of the extraneous material and may be reduced in volume to less than 1/15 of that of the urine. The procedure consists of the following steps: (1) a 10 per cent (v/v) solution of a high molecular weight secondary amine (Amberlite LA-2, Rohm and Haas) in ethyl acetate is washed with formic acid and water, (2) the oestrogens in urine (acidified to pH 2 or 3 with H2SO4) are extracted with the LA-2 solution, (3) the oestrogen fraction is back-extracted from the organic solution with dilute aqueous ammonia.

CONJUGATED OESTROGENS. II

ABSTRACT A method is described for the extraction and separation of free and conjugated oestrogens in urine. Celite 545, a diatomaceous earth, is coated with a high molecular weight secondary amine (Amberlite LA-1, Rohm and Haas, Phila., Pa.) and is used as a chromatographic support for the separation of various free and conjugated oestrogens in urine and in extracts of urine. Elution is carried out with extremely dilute acids. Optimum separation was obtained with a column of Celite coated with LA-1 (formate) in which the conjugated oestrogens in a concentrated extract of urine were eluted with a linear gradient (in the mixing chamber) of formic acid (pH 3.10 to 5.04).

溶媒抽出プロセスにおける分離効率を示す新しい尺度

Separation and decontamination factors for three steps of an extraction process, i.e., extraction, scrubbing, and stripping, as well as an overall decontamination factor for the extraction process as a whole are defined to show the separation efficiency in the process. The equations are derived between these factors and experimental values such as distribution ratios, scrubbing percents, and stripping percents. The equations are applied to the separation of fission products/uranium with tributyl phosphate (TBP) and seven alkyl amines irradiated to the extent of 10/sup 8/ r, in order to follow the radiation effect on separation and decontamination factors. Decontamination factors decrease with increasing dosage in the TBP system, whereas they increase in most amine systems. N-cyclohexyl dilauryl amine and TBP are the best for the decontamination among unirradiated extractants. Amberlite LA-2 is the best among the irradiated. In most cases a scrubbing step is more important than an extraction step as far as the decontamination of fission products/uranium is concerned. (auth)

アルキルアミン-硝酸系における諸元素の行動

The solvent extraction behavior of about sixty chemical elements was extensively surveyed in the alkylamine-nitric acid system, clarifying radiochemically the acid dependence of distribution ratios. The organic phases used were 10% (V/V) Amberlite LA-1 and 5% (V/V) tri-iso-octylamine xylene solution.The highly extractable chemical species were not so many in number through two extraction systems. In most cases the acid dependence curves of a given element were not only similar each other between the two systems, but also resembled to that in 100% TBP-HNO3 system. The exceptional high Kd value of technetium at 1 N HNO3 suggested an application to separating 99mTc from neutron irradiated ammonium molybdate.

Complexes formed between the platinum metals and halide ions. Part 1.—Extraction of hydrohalic acids by solutions of Amberlite LA-2 in carbon tetrachloride

The first page of this article is displayed as the abstract.

Distribution of nitric acid between water and amberlite LA-1 liquid anion exchanger

The solute-solvent interaction between Amberlite LA-1, a long-chain secondary amine extractant dissolved in carbon tetrachloride or benzene and aqueous nitric acid solution up to ∼ 16 M has been investigated by physical and chemical measurements. The first reaction is an acid-base equilibrium leading to the formation of amine nitrate. The quilibrium constants were evaluated as K 1 = 3·8 × 10 5 and 5·4 × 10 5 in carbon tetrachloride and benzene respectively. The second and third reactions postulated involve amine nitrate and associated nitric acid molecules, leading to the formation of a molecular addition compound identified as R 2HNHNO 3·HNO 3 and to the physical partition of associated nitric acid between the aqueous and organic phases. The equilibrium concentration product quotients have the values K 2 = 1·85 for carbon tetrachloride and K 2 = 2·24 for benzene, and the distribution constant has the value K d = 0·1±0·02 for 1 M amine solution in both diluents. The effects of the formation of the amine nitrate aggregates or of the extracted molecular addition compound, or both, are not taken into account. Evidence was obtained that the aggregation of the species in the organic phase is largely a post-equilibrium phenomenon.

Microanalysis with the aid of ion exchangers

The resin spot test is modified by the use of a high molecular weight amine, Amberlite LA-1, in carbon tetrachloride; 0.2 μg of cobalt(II) can be detected rapidly by shaking an acidic solution containing thiocyanate with a 5% amine solution. Amine-impregnated papers can also be used.

アルキルアミン-塩酸系溶媒抽出における諸元素の行動

2級アミンAmberlite LA-1および3級アミントリイソオクチルアミンの2種を抽出剤に選び,ナトリウムからウランまでのできるだけ多数の元素について塩酸濃度を変えてKd値の変化を調べた。希釈剤としてキシレンをとり,抽出剤濃度はAmb. LA-1では10%, TIOAでは5%ときめた。 Kd値の測定は各元素の放射性トレーサを用い,常法のように放射能測定により求めた。得られたAcid Dependence曲線を周期律表の順に配列し,放射化学的分離のための一覧表をつくった。 10% Amb. LA-1および5% TIOAによるKd値は一般に後者の方が高い。曲線の形は相互によく類似している。さらに曲線の形をTBPおよび陰イオン交換樹脂の場合と比較すると,互いに強く類似しているが,アミンおよび陰イオン交換樹脂の場合はスカンジウムおよび重希土類元素に対して高酸度でも高いKd値が得られず,この点でTBPと異なっている。