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Abstract  

A systematic study was performed on the extraction and separation of cadmium from iron halides in pure halo-acid solutions and their mixtures with H2SO4 and H3PO4. As solvents Amberlite LA-2, TBP, nitrobenzene and HDEHP were used. Recommended separation media for the amine are 2M HCl, 1M HBr, 1.12M HCl−2M H2SO4, 0.64M HBr−2M H2SO4, 1.12M HCl−4M H3PO4 0.64M HBr−7M H3PO4 and for TBP the medium 0.64M HBr−4M H3PO4 is the only suitable condition.

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Abstract  

A systematic investigation was carried out on the extraction of Sb(III) and (V) with HDEHP from various acidic, neutral and alkaline solutions. Antimony(III) is best extracted from neutral or slightly acidic solutions, and the E values are nearly the same in the forward and backward extractions. Antimony(V) extraction is high only from concentrated HCl and HClO4, and the E values are much larger in the backward direction. Extraction and separation of Sb(III) and (V) was studied as a function of acidity, alkalinity, anion and water-miscible organic additives in the aqueous phase, as well as the diluent used and HDEHP molarity. Separation factors obtained for Sb(III) and (V) were higher than when using isopropyl ether as solvent, which was hitherto used for this purpose.

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Abstract  

A review is presented on the use of various activation analysis methods for the determination of trace elements in air particulate and related matters. A discussion is given on the contribution of such methods in solving the problem of air pollution in various parts of the world. This work is a part of a program undertaken by this Department for the evaluation of the various analytical techniques as investigative tools in pollution and other environmental studies.

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Abstract  

A comparative study is presented on neutron activation analysis of rock and soil samples using whole reactor neutron spectrum and epithermal neutrons with both relative and monostandard procedures. The latter procedure used with epithermal neutron activation analysis of soil samples necessitated the use of the “effective resonance integrals” which were determined experimentally. The incorporation of the β factor, representing deviation of reactor epithermal neutron flux from 1/E law, is developed in the present work. The main criteria for the choice of one or more of the procedures studied for a given purpose are also indicated. Analysis of 15 trace elements, Ca and Fe in the standard Japanese granite JC-1 using monostandard epithermal neutron activation gave results in good agreement with the average literature values.

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Abstract  

In this study the cleaning time and fate of phosphoric acid on human dental enamel and dentin has been investigated, using the radioactive tracer technique with32P as an indicator of phosphorus. Twenty seconds were found to be sufficient for cleaning the enamel from phosphoric acid, which is used for conditioning, and from formulations produced from its interaction with enamel. It was also found that dentin protection is necessary before conditioning with phosphoric acid due to the retention penetration of the latter through subsurface dentinal tubules. In addition, there seems to be an interaction between phosphoric acid and Ca(OH)2 leading to the formation of a sparingly soluble compound.

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Abstract  

A systematic study is presented on the extraction of Sn(IV) and In(III) halides with benzene, toluene, o-xylene, nitrobenzene, cyclohexane, n-hexane, CHCI 3 and CC14 from H2SO4 solutions. While no extraction of the chlorides of the two elements by these solvents takes place, the extraction of their bromides and iodides is considerable (In) or very high (Sn). In case of Sn(IV), maximum extraction is obtained at 12.6M H~SO4 for the bromide and at 7 9M H 2SO 4 for the iodide. It is easy to separate SbCI 3 from SnCI by extraction with one of the first 3 solvents, and SnBr 4 from InBr~ by extraction with n-hexane. Extraction mechanism of Sn(IV) halides was discussed in view of the results for the above solvents, TBP and amberlite LA2.

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Solvent extraction studies on cadmium

III. Extraction and separation of macroamounts of Cd, Zn and Co halides from sulphuric acid media

Journal of Radioanalytical and Nuclear Chemistry
Authors:
A. Alian
and
A. El-Kot

Abstract  

An extraction study was performed on various concentrations of cadmium, zinc and cobalt halides in the presence of sulphuric acid. A long chain amine (Amberlite LA-2) and an organophosphorus solvent (TBP) have been investigated. In most cases the value of the distribution ratio decreases with the increase of metal concentration in the aqueous phase. The various possibilities of chemical and radiochemical separations of cadmium from accompanying metal species are reported.

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Abstract  

A systematic study is presented on the extraction of60Co and65Zn bromides and chlorides from H2SO4 with tri-n-butyl phosphate (TBP) and Amberlite LA-2. It has been found that the presence of a little HBr or HCl enhances the extraction of the two isotopes with both solvents. The extractions of60Co and65Zn have been studied as functions of the acidity (HBr, HCl or H2SO4) in the aqueous phase, and of the diluent and solvent concentrations in the organic phase. The presence of water-miscible alcohols or acetone enhances extraction. A suggested extraction mechanism is presented in the light of the obtained results.

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Separation of metal halide pairs using Amberlite LA-2 and tri-n-butyl phosphate

III. Separation of silver from cadmium and from zinc

Journal of Radioanalytical and Nuclear Chemistry
Authors:
A. El-Kot
,
A. Ghoneim
, and
A. Alian

Abstract  

Separation factors of silver-cadmium and silver-zinc pairs were determined for Amberlite LA-2 and tri-n-butyl phosphate (TBP) from pure hydrochloric, hydrobromic, sulphuric and orthophosphoric acids as well as from their binary mixtures. The separation of cadmium and zinc from macroamounts of silver can be best achieved from ca. 2M H2SO4. There are many other media suitable for the separation of trace silver from cadmium and zinc matrices.

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Abstract  

A simple method has been developed for the rapid separation of234Th /UX1/ from uranyl nitrate hexahydrate. The method is based on selective dissolution of uranyl nitrate by diethyl ether on a filter paper. It is shown that almost all UX1 is adsorbed by the filter paper which can be desorbed and brought into solution by 5N HCl or HNO3. The effect of different parameters on the separation have also been investigated.

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