Investigation of the Conditions of Extraction of Ion-Associates of 3-Quinuclidinyl Benzilate with Acidic Dyes

1993 ◽  
Vol 58 (2) ◽  
pp. 315-319 ◽  
Author(s):  
Emil Halámek ◽  
Zbyněk Kobliha

Ion-associates of 3-quinuclidinyl benzilate (BZ) with thirteen acidic dyes were examined after their extraction into chloroform. Based on spectrophotometric measurements, the optimum pH of the aqueous phase was established and the extraction yields, distribution ratios, conditional extraction constants and limits of detection were calculated. Bromocresol green and metanil yellow are suggested as reagents for the analysis of BZ.

1988 ◽  
Vol 53 (8) ◽  
pp. 1655-1663 ◽  
Author(s):  
Jan Souček ◽  
Emil Halámek ◽  
Roman Kysilka

The formation of ionic associates of atropine and quinine with bromothymol blue, metanil yellow and cresol red was studied by extraction spectrophotometry. In aqueous solutions, formation of ionic associates was only observed for quinine with bromothymol blue; ionic associates of both dyes with all of the three dyes could be, however, studied by their extraction into chloroform. The conditional extraction constants were calculated for the equilibria involved. The ability of atropine, quinine and bromothymol blue to be extracted into chloroform was examined in dependence on pH and ionic strength of the aqueous phase. The pH1/2 value corresponding to 50% extraction recovery decreases with increasing ionic strength for quinine whereas for atropine the extraction recovery is only slightly affected by a higher ionic strength and for bromothymol blue the pH1/2 (E = 50%) value increases with increasing ionic strength.


1981 ◽  
Vol 46 (8) ◽  
pp. 1901-1905 ◽  
Author(s):  
Oldřich Navrátil ◽  
Jiří Smola

Distribution between aqueous phase and benzene or chloroform was studied for 1-phenyl-3-methyl-4-benzoylpyrazol-5-ones with 2-chloro, 4-methoxy, 3-nitro, and 4-nitro substitution in the benzoyl group (ionic strength of the aqueous phase 0.1) and for hafnium in their presence (ionic strength 2.0). The distribution and dissociation constants of the reagents and the extraction constants of their hafnium complexes were determined. Hafnium was found to be extracted as the HfA4 species. The extraction parameters of the derivatives in question do not differ substantially from those of the parent substance.


1994 ◽  
Vol 59 (3) ◽  
pp. 582-588
Author(s):  
Jan Souček ◽  
Ladislav Belický ◽  
Josef Havel

The protonation and distribution constants of dibenz[b, f]-1,4-oxazepin (CR) were measured. This substance forms stable ion-associates with Acid Red 88, extractable into chloroform. Reextraction with an aqueous phase containing basic fuchsine or safranine T brings about exchange of the CR cation for the basic dye cation. The associates so formed exhibit higher conditional extraction constants and higher molar absorptivities than the initial associates.


1994 ◽  
Vol 59 (3) ◽  
pp. 575-581 ◽  
Author(s):  
Zdeněk Skaličan ◽  
Zbyněk Kobliha ◽  
Emil Halámek

Ion-associates of N,N-diethyllysergamide with the sulfophthaleins: Bromoxylenol Blue, Eriochrome Cyanine R, Xylenol Blue, and Cresol Red, and the azo dyes: Acid Black I and Orange-I were studied by extraction spectrophotometry. The extraction recoveries, distribution ratios, conditional extraction constants and limits of detection and determination were calculated.


2010 ◽  
Vol 150-151 ◽  
pp. 890-894
Author(s):  
Ke Xu Jiang ◽  
Da Wei Fang ◽  
Han Wang ◽  
Bao Xin Wang ◽  
Ying Xiong ◽  
...  

In solvent extraction system of perrhenate with the extractant of N235 at high concentration, the equilibrium molalities of ReO4- were measured at ionic strengths from 0.2 to 2.0 mol.kg-1 in the aqueous phase containing Na2SO4 as the supporting electrolyte from 278.15K to 303.15K. The standard extraction constants K0 at various temperatures were obtained. Thermodynamic quantities for the extraction process were also calculated.


1980 ◽  
Vol 45 (11) ◽  
pp. 3116-3129 ◽  
Author(s):  
Petr Vaňura ◽  
Libor Kuča

The composition of Fe(III) complexes extracted from the aqueous phase of constant ionic strength (1M-(H3,Na3,Fe)A, where H3A denotes citric acid) by the toluene solution of trilaurylamine (TLA) has been determined and the respective extraction constants have been calculated. In the concentration range cFe < 10-2 mol l-1 FeA(TLA)2 and FeA(TLA)4(H3A)2-4 are the predominant complexes in the organic phase. The abundance of the (FeA)3(TLA)6(H3A)2 complex in the organic phase increases at higher equilibrium concentrations of Fe(III) in the aqueous phase and at higher concentrations of TLA.


1998 ◽  
Vol 63 (7) ◽  
pp. 967-976 ◽  
Author(s):  
Oldřich Navrátil ◽  
Zdeněk Skaličan ◽  
Zbyněk Kobliha ◽  
Emil Halámek

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.


2010 ◽  
Vol 6 (3) ◽  
pp. 238-244 ◽  
Author(s):  
Darjito Darjito ◽  
Danar Purwonugroho ◽  
Siti Nasirotun Nisa

One techniques to reduce the concentration of heavy metal Cd(II) in aqueous solution is adsorption by chitosan. To modify the surface textures and expose the active binding sites, composite biosorbent has been prepared by coating chitosan onto alumina. The aims of this research were to identify the functional group of chitosan-alumina, to characterize adsorption of Cd(II) by using chitosan-alumina adsorbent including optimum pH, optimum agitation time, and to determine the adsorption capacity of the adsorbent. The functional group of chitosan-alumina was identified by infrared spectrophotometer. Determination of the optimum condition was carried out at 40 ppm Cd(II), 125 rpm and 0,1 g adsorbent. Calculation of adsorpted Cd(II) based on its concentration in aqueous phase before and after adsorption process. The concentrations of Cd(II) in aqueous phase after adsorption process  were determined by using Atomic Absorption Spectroscopy (AAS). Identified functional groups of chitosan-alumina were -OH (3466.39 cm-1), -NH amine (1625.15 cm-1), C=O (1703.30 cm-1), and Al-O (1302.07 cm-1). The optimum pH was reached at pH 7, optimum agitation time at 15 minutes, and adsorption capacity of chitosan-alumina was 15.35 ± 0.05 mg/g.   Keywords: adsorption, chitosan-alumina, characterization of adsorption


1987 ◽  
Vol 52 (2) ◽  
pp. 322-328 ◽  
Author(s):  
Petr Linhart ◽  
Oldřich Navrátil ◽  
Josef Havel ◽  
Milan Vrchlabský

The extraction of Sc, Ce, Pm, and Eu from aqueous solutions of HClO4 and HNO3 into organic phases constituted by solutions of dialkylphosphoric acids in Freon 113 was studied. The effects of the kind of inorganic acid, concentration of hydrogen ions in the aqueous phase and concentration of the extracting agent in the organic phase were examined. Based on the dependences of the distribution ratios of the metals on the above variables, the compositions of the extractable complexes were determined and the extraction constants calculated. The dimerization constants and distribution constants of the monomer were also determined for dibutylphosphoric and bis(2-ethylhexyl)phosphoric acids.


1980 ◽  
Vol 45 (4) ◽  
pp. 1221-1226 ◽  
Author(s):  
Oldřich Navrátil ◽  
Pavel Linhart

The partition of 1-phenyl-3-methyl-4-benzoylpyrazolone-5 (HA) between aqueous solutions of HClO4 and NaClO4, ionic strength 0.1, and Freon 113 or its 2 : 1 mixture with benzene was studied. The logarithms of the HA distribution constants are 2.84 ± 0.10 and 3.39 ± 0.15 for the two organic phases, respectively. The extraction curves of cerium(III) and europium(III) revealed that in dependence on the pH of the aqueous phase, the metals are transferred into the organic phase in the form of the MA3 complexes (M = Ce, Eu). The stability constants of the complexes MAn in the aqueous phase were determined along with their distribution and extraction constants. For cobalt, zinc, and hafnium, a part of the extraction curves could only be studied, only the extraction constants were therefore determined. The sparing solubility of HA in Freon 113 can be circumvented by using a Freon-benzene mixture 2 : 1, which is still practically incombustible.


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