caa a22 4500 378917706 CHVBK 20180305123557.0 cr unu---uuuuu 161128e20040101xx s 000 0 eng 10.1524/ract.92.1.25.25409 doi (NATIONALLICENCE)gruyter-10.1524/ract.92.1.25.25409 Studies on the equilibrium and mechanism of Th(IV) extraction by CYANEX 272 in kerosene from nitrate medium [Elektronische Daten] [S. I. El-Dessouky, N. E. El-Hefny, Jacqueline A. Daoud] The extraction behavior of Th(IV) from aqueous nitrate medium by the commercial bis(2,4,4-trimethylpentyl) phosphinic acid extractant, (CYANEX 272) in kerosene has been studied. Batch extraction investigation was firstly carried out to elucidate the stoichiometry of the extracted Th(IV) species and deduce the suitable conditions to be applied in the kinetic studies using Lewis cell technique. The extracted species was found to be [Th(OH)3A(HA)3] on the basis of slope analysis method. The different parameters affecting the extraction rate of Th(IV) as well as temperature were separately investigated, and a rate equation was deduced. The experimental results indicate that the rate of Th(IV) extraction is first order dependent on CYANEX 272 concentration, first order dependent on hydrogen ion concentration and inversely first order dependent on thorium concentration. The proposed mechanism for the extraction process is controlled by chemical reaction in the bulk phase rather than at the interface. © 2004 Oldenbourg Wissenschaftsverlag GmbH Laboratory techniques, experiments nationallicence Analytical chemistry nationallicence Inorganic chemistry nationallicence El-Dessouky S. I. aut El-Hefny N. E. aut Daoud Jacqueline A. aut Radiochimica Acta/International journal for chemical aspects of nuclear science and technology Oldenbourg Wissenschaftsverlag GmbH 92/1/2004(2004-01-01), 25-30 0033-8230 92:1/2004<25 2004 92 ract https://doi.org/10.1524/ract.92.1.25.25409 text/html Onlinezugriff via DOI 1 research article jats NATIONALLICENCE 856 40 https://doi.org/10.1524/ract.92.1.25.25409 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- El-Dessouky S. I. aut NATIONALLICENCE 700 1- El-Hefny N. E. aut NATIONALLICENCE 700 1- Daoud Jacqueline A. aut NATIONALLICENCE 773 0- Radiochimica Acta/International journal for chemical aspects of nuclear science and technology Oldenbourg Wissenschaftsverlag GmbH 92/1/2004(2004-01-01), 25-30 0033-8230 92:1/2004<25 2004 92 ract CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-gruyter