Search Results

You are looking at 41 - 50 of 92 items for :

  • "8-hydroxyquinoline" x
  • Refine by Access: All Content x
Clear All

Abstract  

Radiometric X-ray fluorescence analysis was used for the determination of Mn, Fe, Cu, Zn and Pb in wastewater and sludges from three wastewater treatment plants in Bratislava (SR). Metals were determined in wastewaters after preconcentration by 8-hydroxyquinoline and in sludges by drying and pressing to pellets.238Pu and109Cd was used for excitation of fluorescence radiation.

Restricted access

Abstract  

Two methods of concentration of Ag, As, Cd, Co, Cr, Cu, Fe, Hg, In, Mo, Mn, Sb, Sc, Se, W and Zn from water have been elaborated. The trace elements are preconcentrated by coprecipitation with thionalide at pH 9, 1 and 0 or by sorption on ion exchange resin Dowex 1×2 loaded with 8-hydroxyquinoline-5-sulfonic acid at pH 7.

Restricted access

Abstract  

54Mn is analyzed in complex food ash of high cationic environment. The initial step is an extraction atpH 2.7 with hexane containing di(2-ethylhexyl) phosphoric acid (HDEHP) to complex the54Mn and other nuclides. The manganese is reextracted into an alkaline EDTA buffer which is washed with 1% 8-hydroxyquinoline in chloroform containing 5% isoamyl alcohol. The54Mn is determined by gamma spectrometry with recoveries ranging from 96.6 to 99.4%.

Restricted access

Abstract  

The preconcentration of cadmium from aqueous colloid solution containing 8-hydroxyquinoline as extractant, laurylsulphate natrium as surfactant,n-butanol as co-surfactant was performed using micellar ultrafiltration technique. Filters with different pore size and materials were used to achieve a separation from liquid solutions. The cadmium recoveries depending on different conditions (pH, concentration of surfactant) were determined and the results are explained in the terms of colloidal parameters in the compare with the classical solvent extraction.

Restricted access

Abstract  

Synergistic extraction of Co(II) with 8-hydroxyquinoline (Hq)/decanoic acid [(HR)2] solution mixtures in benzene and chloroform was carried out at 25°C. The aqueous ionic strength and the total concentration of cobalt(II) were 0.1 (NaCl) and 1·10–5–1·10–3M, respectively. The synergistic effect is interpreted by the formation of the mixed ligand ion-pair complexes: [(Coq(Hq)2(HR))+, R] and [(Coq(Hq)2(HR)3)+, R] in benzene and chloroform, respectively.

Restricted access

Abstract  

A rapid radiochemical procedure based on the removal of mercury, selenium, arsenic and antimony by columns of C18-bonded silica gel or activated carbon after their selective complexation in sulphate/nitrate media by ammonium pyrrolidine-dithiocarbamate, diethylammonium diethyldithiocarbamate, potassium ethyl xanthate, bismuthiol II or 8-hydroxyquinoline, was examined. Comparisons were made of the ability of the two ion retention media to remove these metal ions and to allow their regeneration and recycling. The effectiveness of this technique was demonstrated by analysis of horse kidney and human diet, International Atomic Energy Agency biological reference materials, for mercury and selenium.

Restricted access

Abstract  

The results for the extractions of divalent (manganese, cobalt, zinc and cadmium) and trivalent (gallium and indium) metals and hexavalent uranium from aqueous solutions by various extractants such as organophosphorus compounds (tributyl phosphate, trioctylphosphine oxide, di-(2-ethylhexyl)phosphoric acid and 2-ethylhexyl 2-ethylhexylphosphonic acid), sulfur-containing compound (dihexyl sulfoxide), high-molecular weight amines (trioctylamine and trioctylmethylammonium chloride) and 7-alkylated hydroxyquinoline (7-(5,5,7,7-tetramethyl-1-octen-3-yl)-8-hydroxyquinoline are discussed in the viewpoint of separation chemistry.

Restricted access

Abstract  

Uranium is extracted by a water-in-oil emulsion consisted from 0.01M 8-hydroxyquinoline /HOx/ in cyclohexane and aqueous solution or Arsenazo III and glycine. Analyzed solution is adjusted to 0.02M 1,2-diaminocyclohexane-N,N,N,N-tetraacetic acid /DCTA/ and pH 7.5±0.1. Preconcentration factor of about 400 can be achieved and when the uranium concentration in the outer solution is above 5 g.dm–3 /5 ppb/ its spectrophotometric determination in the inner solution of the double emulsion system is possible. Thorium practically does not interfere at the ratio Th:U=20:1.

Restricted access

Abstract

TG-DTG-DTA has been used to characterize various isomers of CoCl2·2(CH3C6H4NH2). Thermal analysis is further used to analyse the binary mixtures of these isomers. DTA recorded after different elapsed times follows the progress of reaction between cobalt chloride and benzocaine where progressively small endotherms are associated with starting materials. The application of thermal analysis to following the solid-solid reactions between metal acetates and 8-hydroxyquinoline was highlighted. The stoichiometry of such reactions was confirmed from the decrease in intensity of an endotherm as one increases the stoichiometry.

Restricted access

Abstract  

The neutron activation method has been applied to the determination of Ag, Cd, Co, Cr, Cu, Fe, Hg, Mo, Se and Zn in waters and wastes. The method involves decomposition of organic substances by ozonation, preconcentration of elements to be determined by coprecipitation with thionalide at pH 9 or sorption on Dowes 1×2 loaded with 8-hydroxyquinoline-5-sulfonic acid at pH 7, irradiation of the concentrate, radiochemical separation of the respective radioisotopes and gamma spectrometric measurement of the activity. Accuracy and precision of the determination have been evaluated.

Restricted access