scholarly journals DISTRIBUTION OF THORIUM (IV) IONS IN AQUEOUS EXFOLIATING SYSTEM CONTAINING ANTIPYRINE AND SULFOSALICYLIC ACID

2021 ◽  
Vol 64 (5) ◽  
pp. 19-23
Author(s):  
Mikhail I. Degtev ◽  
Aleksandra A. Yuminova
Keyword(s):  
Aqueous Phase ◽  
Room Temperature ◽  
Photometric Determination ◽  
Sulfosalicylic Acid ◽  
Salting Out ◽  
Maximum Extraction ◽  
Instrumental Methods ◽  
Toxic Organic Solvents ◽  
Nitrate Solutions

The possibilities of an aqueous delaminating system containing antipyrine (AP) and sulfosalicylic acid (SSA) for extracting macro - and microamounts of thorium (IV) were studied. The proposed extraction system eliminates the use of toxic organic solvents. The dependences of the distribution of metal from nitrate solutions between phases on the concentration of reagents, acidity of the medium, the amount of inorganic salting-out agent (NaNO3, NH4NO3, Na2SO4) and the volume of the aqueous phase are determined, and optimal conditions for extraction are found. It is shown that in the organic phase with a volume of 1.6 ml at room temperature, macro-and microamounts of thorium (IV) are extracted by 88 and 90%, respectively. The maximum extraction of the cation is achieved at the ratio of AP: SSA = 2.0 : 1.0 and their concentration, mol/l: 0.6: 0.3, while the acidity of the medium created by nitric acid should be equal to 0.015 mol/l (pHequ. = 1.8-1.9). The extraction of thorium (IV) becomes quantitative if inorganic salts (sodium sulfate, sodium nitrate) are introduced into the AP – SSA – 0,015 mol/l HNO3 – H2O system, which, by reducing the activity of water, increase the concentration of reagents in the aqueous phase. The concentration of salting-out agents should correspond to 1.0 and 2.5 mol/l. A mechanism for the distribution of a mixed thorium (IV) complex containing AP, SSA, nitrate ions, solvated with a salt of antipyrinium sulfosalicylate is proposed. The extract is mixed in any relationship with distilled water, providing the use of various instrumental methods of analysis. A method for extraction-photometric determination of thorium (IV) with a toron indicator has been developed. The limit for the fulfillment of the Bouguer-Lambert-Beer law is established. The apparent coefficient of light absorption is calculated (ε = 1.7∙104).

A method for selective separation of scandium (III) from yttrium and a number of rare-earth elements for its subsequent determination

2018 ◽  
Vol 84 (11) ◽  
pp. 23-27
Author(s):  
M. I. Degtev ◽  
A. A. Yuminova ◽  
A. S. Maksimov ◽  
A. P. Medvedev
Keyword(s):  
Rare Earth ◽  
Aqueous Phase ◽  
Selective Isolation ◽  
Optimum Ratio ◽  
Extraction Condition ◽  
Sulfosalicylic Acid ◽  
Salting Out ◽  
Subsequent Determination ◽  
Toxic Organic Solvents ◽  
Metal Ions Extraction

The possibility of using an aqueous stratified system of antipyrine — sulfosalicylic acid — water for the selective isolation of scandium macro- and microquantities for subsequent determination is studied. The proposed extraction system eliminates the usage of toxic organic solvents. The organic phase with a volume of 1.2 to 2.0 ml, resulting from delamination of the aqueous phase containing antipyrine and sulfosalicylic acid is analysed to assess the possibility of using such systems for metal ions extraction. Condition necessary for the formation of such a phase were specified: the ratio of the initial components, their concentration, presence of inorganic salting out agents. The optimum ratio of antipyrine to sulfosalicylic acid is 2:1 at concentrations of 0.6 and 0.3 mol/liter in a volume of the aqueous phase of 10 ml. The obtained phase which consists of antipyrinium sulfosalicylate, free antipyrine and water, quantitatively extracts macro- and microquantities of scandium at pH = 1.54. Macro- and microquantities of yttrium, terbium, lanthanum, ytterbium and gadolinium are not extracted under the aforementioned conditions thus providing selective isolation of scandium from the bases containing yttrium, ytterbium, terbium, lanthanum, and gadolinium.

Extraction of americium with benzyldibutylamine from nitrate solutions

1979 ◽  
Vol 44 (8) ◽  
pp. 2366-2372 ◽  
Author(s):  
Věra Jedináková ◽  
Jana Cibulková ◽  
Libor Kuča
Keyword(s):  
Nitric Acid ◽  
Chemical Analysis ◽  
Ir Spectra ◽  
Aqueous Phase ◽  
Organic Phase ◽  
Nuclear Fission ◽  
Salting Out ◽  
Nitrate Medium ◽  
Separation Factors ◽  
Nitrate Solutions

The extraction of Am(III) with benzyldibutylamine from nitrate medium was examined in dependence on the concentration of nitric acid, kind and concentration of the salting-out agent in the aqueous phase, and on the solvent. Am(III) is extracted into the organic phase in the form of {(R3NH+)α, Am(NO3)52-}. The IR spectra of the organic phase are discussed and confronted with the results of the chemical analysis of the organic phase. The extraction of Am(III) and of lanthanoids was found to be considerably higher than that of some products of corrosion and nuclear fission (Cs, Sr, Zr, Fe), which is documented by the high values of the separation factors.

Extraction of Selected Organic Bases from Water into Chloroform by Means of the Cobaltacarborane Anion

1998 ◽  
Vol 63 (7) ◽  
pp. 967-976 ◽  
Author(s):  
Oldřich Navrátil ◽  
Zdeněk Skaličan ◽  
Zbyněk Kobliha ◽  
Emil Halámek
Keyword(s):  
Solvent Extraction ◽  
Aqueous Phase ◽  
Organic Nitrogen ◽  
Base Cations ◽  
Photometric Determination ◽  
Nitrogen Base ◽  
Organic Bases ◽  
Quaternary Salts ◽  
Extraction Constants

The cobaltacarborane anion labelled with 60Co was used to study the solvent extraction and stability of its ion associates with a series of organic nitrogen base cations or quaternary salts, some of which are psychoactive. The aqueous phase was 0.1 M HCl, the organic phase was chloroform. The extraction constants of the ion associates were calculated. A method was devised for competitive extraction of ion associates with additional dye anions which are used in the extraction-photometric determination of selected bases.

scholarly journals Separation of Th from leachate of monazite sulphation process using amine solvent extraction

2021 ◽  
Vol 8 (1) ◽  
pp. 44-49
Author(s):  
Xuan Dinh Luu ◽  
Thanh Thuy Nguyen ◽  
Ba Thuan Le ◽  
Mai Huong Le Thi
Keyword(s):  
Solvent Extraction ◽  
Aqueous Phase ◽  
Room Temperature ◽  
Amino Nitrogen ◽  
Primary Aliphatic Amine ◽  
Extraction Capacity ◽  
Alkyl Groups ◽  
Maximum Extraction ◽  
Extraction Device ◽  
Secondary Carbon

The solvent extraction is one of the most common method for separating Th from solution. Primary amine has higher selectivity for the extraction of Th(IV) than U(VI) and RE(III) in sulfate media. N1923 (a primary aliphatic amine with amino nitrogen linked to a secondary carbon consisting of branched alkyl groups in C19–23 range) is commonly used to extractTh. At room temperature using 0.1M N1923 amine as solvent in this work, the results showed thatthorium maximum extraction capacity was about 2.5g/L with concentration of sulfuric acid in the aqueous phase was 1M and for 3 minutes shaking. At room temperature for 3 minutes shaking the best conditions for scrubbing processwas using the mixture of acids H2SO4 0.2M and HNO3 0.1M, result inover 75%, Th was scrubbed in the aqueous phase only 0.7%. The separation of Th from leachate of monazite sulphation process was carried out on a multistage continuous flow extraction device (12 boxes), the thorium purity was 98%. Therefore, the use of amine solvents can purify thorium from rare-earth solutions in a sulfate medium

Ionic strength effect on extraction of potassium complexed with crown ether 18-crown-6. Preliminary communication

1981 ◽  
Vol 59 (10) ◽  
pp. 1548-1551 ◽  
Author(s):  
Izaak Maurits Kolthoff
Keyword(s):  
Crown Ether ◽  
Aqueous Phase ◽  
Sea Water ◽  
Critical Study ◽  
Salting Out ◽  
Ionic Strength Effect ◽  
Sodium Magnesium ◽  
Phase Selectivity ◽  
Preliminary Communication

As part of a broad study of the factors which affect extraction of salts of cations, complexed with an uncharged ligand, L, a critical study has been made of the extraction into dichloromethane of K+ complexed with 18-crown ether-6 in the form of picrate (LKPi). In using extraction analysis for the determination of very small concentrations of K+ in the presence of other salts activities of (K+)w and (Pi−)w in the aqueous phase must be written in the expression for Kext(LKPi). The salting out effect on P(L) = [L]0/[L]w can greatly affect the concentration of potassium ions left in the aqueous phase. Selectivity of K+/Na+ in extractions with 18-crown-6 has been determined.The extraction method is very suitable for the determination of traces of potassium in salts of sodium, magnesium, and calcium after calibration with, e.g., potassium chloride in potassium-free salts and also, after proper calibration, in routine analysis of liquids which contain little K+ and a large excess of Na+ (e.g. sea water, blood serum).

Extraction of dithiocarbamic acids from solutions of their salts

1982 ◽  
Vol 47 (11) ◽  
pp. 2876-2881 ◽  
Author(s):  
Drahomír Oktavec ◽  
Bohumil Síleš ◽  
Ján Remeň ◽  
Václav Konečný ◽  
Ján Garaj
Keyword(s):  
Aqueous Phase ◽  
Time Dependent ◽  
Absorption Bands ◽  
Decomposition Reactions ◽  
Maximum Extraction ◽  
The Stability ◽  
Kinetics Of ◽  
Alkali Salts ◽  
Nm Range

The extraction of dithiocarbamic acids with chloroform from aqueous phase containing their alkali salts has been investigated with regard to the fact that absorbing strongly in the 200-310 nm range, the acids interfere with the spectrophotometric determination of metals whose dithiocarbamate ligands exhibit their analytical absorption bands in that region. The amount of the dithiocarbamic acids formed depends on the kinetics of their formation and decomposition reactions and on the pH of the aqueous phase. The stability of the acids in chloroform extracts is highly time dependent. The maximum extraction of the acids (R2NCS2H) is attained at the following pH (R, pH): CH3 5.0, C2H5 5.9, C3H8 6.3, C4H9 6.8, C5H11 6.9, C6H13 6.9, iso-C3H7 7.2, iso-C4H9 6.9; for (CH3, iso-C3H7)NCS2H 7.3, C5H10NCS2H 7.2, C4H8ONCS2H 5.2.

Interactions Between Al and Cr Thin Films

1976 ◽  
Vol 34 ◽  
pp. 638-639
Author(s):  
R. M. Anderson ◽  
T. M. Reith ◽  
M. J. Sullivan ◽  
E. K. Brandis
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Vacuum System ◽  
Processing Temperature ◽  
Diffusion Couples ◽  
Electronic Circuits ◽  
Intermetallic Formation ◽  
Si Substrates ◽  
Aluminum Silicon

Thin films of aluminum or aluminum-silicon can be used in conjunction with thin films of chromium in integrated electronic circuits. For some applications, these films exhibit undesirable reactions; in particular, intermetallic formation below 500 C must be inhibited or prevented. The Al films, being the principal current carriers in interconnective metal applications, are usually much thicker than the Cr; so one might expect Al-rich intermetallics to form when the processing temperature goes out of control. Unfortunately, the JCPDS and the literature do not contain enough data on the Al-rich phases CrAl7 and Cr2Al11, and the determination of these data was a secondary aim of this work.To define a matrix of Cr-Al diffusion couples, Cr-Al films were deposited with two sets of variables: Al or Al-Si, and broken vacuum or single pumpdown. All films were deposited on 2-1/4-inch thermally oxidized Si substrates. A 500-Å layer of Cr was deposited at 120 Å/min on substrates at room temperature, in a vacuum system that had been pumped to 2 x 10-6 Torr. Then, with or without vacuum break, a 1000-Å layer of Al or Al-Si was deposited at 35 Å/s, with the substrates still at room temperature.

STEM and ELS Observation of Early Oxide Formation on the Surface of Cr Thin Films

1980 ◽  
Vol 38 ◽  
pp. 412-413
Author(s):  
Fumio Watari ◽  
J. M. Cowley
Keyword(s):  
Thin Films ◽  
Optical System ◽  
Room Temperature ◽  
Oxide Formation ◽  
Initial Nucleation ◽  
Diffraction Patterns ◽  
Relationship Of ◽  
Multiple Twinning ◽  
Moderately High Temperature

STEM coupled with the optical system was used for the investigation of the early oxidation on the surface of Cr. Cr thin films (30 – 1000Å) were prepared by evaporation onto the polished or air-cleaved NaCl substrates at room temperature and 45°C in a vacuum of 10−6 Torr with an evaporation speed 0.3Å/sec. Rather thick specimens (200 – 1000Å) with various preferred orientations were used for the investigation of the oxidation at moderately high temperature (600 − 1100°C). Selected area diffraction patterns in these specimens are usually very much complicated by the existence of the different kinds of oxides and their multiple twinning. The determination of the epitaxial orientation relationship of the oxides formed on the Cr surface was made possible by intensive use of the optical system and microdiffraction techniques. Prior to the formation of the known rhombohedral Cr2O3, a thin spinel oxide, probably analogous to γ -Al203 or γ -Fe203, was formed. Fig. 1a shows the distinct epitaxial growth of the spinel (001) as well as the rhombohedral (125) on the well-oriented Cr(001) surface. In the case of the Cr specimen with the (001) preferred orientation (Fig. 1b), the rings explainable by spinel structure appeared as well as the well defined epitaxial spots of the spinel (001). The microdif fraction from 20A areas (Fig. 2a) clearly shows the same pattern as Fig. Ia with the weaker oxide spots among the more intense Cr spots, indicating that the thickness of the oxide is much less than that of Cr. The rhombohedral Cr2O3 was nucleated preferably at the Cr(011) sites provided by the polycrystalline nature of the present specimens with the relation Cr2O3 (001)//Cr(011), and by further oxidation it grew into full coverage of the rest of the Cr surface with the orientation determined by the initial nucleation.

A New Method for Direct Determination of the Recoilless Fraction with Application to Magnetic Nanoparticles

2002 ◽  
Vol 721 ◽  
Author(s):  
Monica Sorescu
Keyword(s):  
Room Temperature ◽  
Average Particle Size ◽  
Direct Determination ◽  
Average Particle ◽  
Lattice Method ◽  
Recoilless Fraction ◽  
Single Room ◽  
Magnetite Particles ◽  
Physical Mixtures

AbstractWe propose a two-lattice method for direct determination of the recoilless fraction using a single room-temperature transmission Mössbauer measurement. The method is first demonstrated for the case of iron and metallic glass two-foil system and is next generalized for the case of physical mixtures of two powders. We further apply this method to determine the recoilless fraction of hematite and magnetite particles. Finally, we provide direct measurement of the recoilless fraction in nanohematite and nanomagnetite with an average particle size of 19 nm.

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