Extraction Properties of 1,2,3-Triazole Modified Carbamoylmethylphosphine Oxide in Nitric Acid Media

Abstract

A novel polyfunctional neutral organophosphorus compound, 2-(diphenylphosphoryl)-N,N-diethyl-3-(1-phenyl-1H-1,2,3-triazol-4-yl)propanamide (I), was synthesized and studied as an extractant for Pd(II), Ln(III), U(VI), and Th(IV) from HNO₃ solutions. The influence of aqueous and organic phases on the extraction efficiency was elucidated and stoichiometry of the complexes extracted was determined. The introduction of a 1,2,3-triazole fragment into the methylene bridge of diphenyl(diethylcarbamoylmethyl)phosphine oxide resulted in a considerable increase of the efficiency of Pd(II) extraction. The potentialities of carbon nanotubes impregnated with compound I for the preconcentration of Pd(II) from nitric acid solutions are demonstrated. The introduction of a 1,2,3-triazole fragment into the methylene bridge of a CMPO molecule does not essentially change the extraction efficiency of compound I towards U(VI) and Ln(III) but drastically decreases the Th(IV) extraction and change the order in the extractactability of U(VI) and Th(IV) with this compound from HNO₃ solutions.

Keywords:

• extraction
• uranium(VI)
• thorium(IV)
• lanthanides(III)
• palladium(II)
• carbamoylmethylphosphine oxides
• 1,2,3-triazole
• carbon nanotubes