STUDY OF ANION EXCHANGE EXTRACTION OF SOME ANIONIC COMPLEXES OF IRON (III) BY ORGANIC SOLUTIONS OF QUARTERLY AMMONIUM SALTS

The anion-exchange extraction of salicylate, thiosulphate and thiocyanate iron (III) complexes by solutions of chlorides of quaternary ammonium salts (QAS) in organic solvents (toluene, carbon tetrachloride, ethyl acetate, isobutyl alcohol, nitrobenzene) was studied. The composition of the iron (III) anionic complexes was established by the analysis of the calibration curves E = f(pCFe (III)) constructed from iron (III) solutions against the background of various contents of thiocyanate, thiosulphate and salicylate ions and the steepness of the electrode function. As an indicator electrode the ion-selective electrode was used with a membrane, which based on a nitrobenzene solution of tetradecylammonium bromide. The solution containing of alkyldimethylbenzylammonium chloride and alkyldimethylethylbenzylammonium chloride and the corresponding organic solvent were mixed in a ratio of 1:1. An organic layer containing the QAS was selected. The anion-exchange extraction was provided in contact with aqueoses solutions of Fe(III) anionic complexes. The extraction process is estimated quantitatively using a distribution coefficient (D). The value of D is calculated taking into account the iron (III) concentration in the aqueous phase before and after extraction. The content of iron (III) in solutions is determined spectrophotometrically (λ = 440 nm). It is established that the value of the distribution coefficient depends on the permittivity (ε) of the organic solvent. In the row toluene - carbon tetrachloride - ethyl acetate - isobutyl alcohol - nitrobenzene, the permittivity increases. In the same sequence, D increases for all studied complex iron(III) ions. Moreover, a decrease in the concentration of the extracted particle leads to an insignificant decrease in the value of the distribution coefficient. The composition and stability of the complex iron (III) ion have a significant effect on the extraction activity.

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STUDY OF ANION EXCHANGE EXTRACTION OF SOME ANIONIC COMPLEXES OF IRON (III) BY ORGANIC SOLUTIONS OF QUADERIC AMMONIUM SALTS

IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA ◽

10.6060/ivkkt201962fp.5782 ◽

1970 ◽

Author(s):

Yulia I. Matyushkina ◽

Alexandr A. Shabarin

Keyword(s):

Carbon Tetrachloride ◽

Organic Solvent ◽

Ethyl Acetate ◽

Distribution Coefficient ◽

Anion Exchange ◽

Ammonium Salts ◽

Organic Layer ◽

Isobutyl Alcohol ◽

Anionic Complexes ◽

Exchange Extraction

The anion-exchange extraction of salicylate, thiosulphate and thiocyanate iron (III) complexes by solutions of quaternary ammonium salts (QAS) chlorides in organic solvents (toluene, carbon tetrachloride, ethyl acetate, isobutyl alcohol, nitrobenzene) was studied. The composition of the iron (III) anionic complexes was established by the analysis of the calibration curves E = f (pCFe (III)) constructed from iron (III) solutions against the background of various contents of thiocyanate, thiosulphate and salicylate ions and the steepness of the electrode function. As an indicator electrode was used the ion-selective electrode with a membrane, which based on a nitrobenzene solution of tetradecylammonium bromide. The solution containing of alkyldimethylbenzylammonium chloride and alkyldimethylethylbenzylammonium chloride and the corresponding organic solvent were mixed in a ratio 1: 1. An organic layer containing the QAS was selected. The anion-exchange extraction was provided in contact with aqueoses solutions of Fe(III) anionic complexes. The extraction process is estimated quantitatively using a distribution coefficient (D), the value of D is calculated taking into account the iron (III) concentration in the aqueous phase before and after extraction. The content of iron (III) in solutions is determined spectrophotometrically (λ = 440 nm). It is established that the value of the distribution coefficient depends on the permittivity (ε) of the organic solvent. In the row toluene - carbon tetrachloride - ethyl acetate - isobutyl alcohol - nitrobenzene, the permittivity increases. In the same sequence, D increases for all studied complex iron(III) ions. Moreover, a decrease in the concentration of the extracted particle leads to an insignificant decrease the value of the distribution coefficient. The composition and stability of the complex iron (III) ion have a significant effect on the extraction activity.

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EXTRACTION OF ANIONIC CADMIUM COMPLEXES WITH ORGANIC SOLUTIONS OF QUATERNARY AMMONIUM SALTS

IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA ◽

10.6060/ivkkt.20206310.6224 ◽

2020 ◽

Vol 63 (10) ◽

pp. 30-35

Author(s):

Yulia I. Matyushkina ◽

Alexandr A. Shabarin

Keyword(s):

Carbon Tetrachloride ◽

Distribution Coefficient ◽

Quaternary Ammonium ◽

Cadmium Concentration ◽

Quaternary Ammonium Salts ◽

Ammonium Salts ◽

Isobutyl Alcohol ◽

Cadmium Complexes ◽

Iodide Ions ◽

Anionic Complexes

The anion-exchange extraction of thiocyanate, chloride and iodide cadmium complexes by solutions of quaternary ammonium salts chlorides in organic solvents (toluene, carbon tetrachloride, ethyl acetate, isobutyl alcohol, nitrobenzene) was studied. Extraction involves solutions of alkyl dimethylbenzylammonium chlorides (R-N+(CH3)2-CH2C6H5-Cl-) and alkyl dimethylethyl-benzylammonium (R-N+(CH3)2-CH2-CH2C6H5-Cl-), where R is a straight alkyl chain, mainly C12 - C14. The composition of the cadmium anionic complexes was established by the analysis of the calibration curves E = f (pCCd (II)) constructed from cadmium sulfate solutions against the background of various contents of thiocyanate, chloride and iodide ions (ndicator electrode - ion-selective electrode with a membrane, which based on a nitrobenzene solution of tetradecylammonium bromide). The extraction process is estimated quantitatively using a distribution coefficient (D). The value of D is calculated taking into account the cadmium concentration in the aqueous phase before and after extraction. The dependence of the distribution coefficient on the organic solvent dielectric constant, the concentration and stability of the anionic complexes of cadmium is shown. So, for the indicated cadmium acidocomplexes, the minimum D values were obtained using low-polar toluene and carbon tetrachloride, and the maximum values were obtained using highly polar isobutyl alcohol and nitrobenzene. If the concentration of cadmium (II) is reduced by a factor of 100 for the cadmium rhodanide and iodide complexes, the value of D decreases by 1.6-1.9 times, for the chloride complex, by 1.2 times in the case of polar isobutyl alcohol and nitrobenzene, and 2.9-3.5 times in the case of low-polar solvents. It was experimentally established that in the series [Cd(SCN)4]2- - [CdI4]2-- [CdCl4]2- the value of D decreases for all the studied systems. The observed regularity is related both to the stability of the corresponding cadmium (II) complexes in aqueous solutions and to their hydrophobicity.

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