An overview of the recovery of acid from spent acidic solutions from steel and electroplating industries.

A new series of neutral bifunctional extractants, alkyl(phenyl)-N,N-dialkylcarbamoylmethylphosphine oxides, has been prepared and studied as extractants for Am(III) from nitric acid media. Two types of alkyl(phenyl)-N,N-dialkyl CMPO compounds were prepared, one containing N,N-diethyl groups and the other containing N,N-diisobutyl groups. The N,N-diethyl series contained hexyl(phenyl) and 6-methylheptyl(phenyl) derivatives, abbreviated HφDECMPO, and 6-MHφDECMPO, respectively. The N,N-diisobutyl series contained the n-octyl(phenyl), 6-methylheptyl(phenyl), and the 2-ethylhexyl(phenyl) derivatives, abbreviated OφD[IB]CMPO, 6-MHφD[IB]CMPO, and 2-EHφD[IB]CMPO, respectively. Third power extractant dependencies for the extraction of Am(III) from 0.5 and 3 M HNO3 were obtained at low (<0.25 M) concentrations of extractant, but higher power dependencies were obtained above 0.25 M extractant from 3 M HNO3. The HφDECMPO, 6-MHφDECMPO, 6-MHφD[IB]CMPO, and OφD[IB]CMPO [all 0.5 M in diethylbenzene (DEB)] are si...

Selected Alkyl(phenyl)-N,N-dialkylcarbamoylmethylphosphine Oxides as Extractants for Am(III) from Nitric Acid Media

The extraction behavior of selected transplutonium(III) and lanthanide(III) ions fromnitrate solution was studied using relatively pure dihexyl-N, N-diethyl-carbamoylmethylphosphonate (DHDECMP). The data obtained for Am(III) and Eu(III) using DHDECMP were compared with analogous measurements obtained with dibutyl butylphosphonate (DB[BP]) and in certain cases with dihexyl-N, N-diethylcarbamoylethylphosphonate (DHDECEP). It was found that both the nitrate and extractant concentration dependencies were third power. The Kd 's for Am(III) and for Eu(III) measured from low acid LiNO3 solutions were similar for DHDECMP, DHDECEP, and DB[BP], thus giving no evidence for any significant chelation effect for DHDECMP. Significant differences among DHDECMP, DHDECEP, and DB[BP] are found for the extraction of Am(III) and Eu(III) from 1 to 5 M HNO3. These differences are explained by the ability of DHDECMP (and to a lesser extent, DHDECEP) to buffer itself against HNO3 by protonation of the amide group. The Kd...

Extraction of selected transplutonium(III) and lanthanide(III) ions by dihexyl-N,N-diethylcarbamoylmethylphosphonate from aqueous nitrate media

Uranyl chelate complexes

Bis-(disubstitutedphosphinyl)-alkanes—IV: Extraction of mineral acids, uranium (VI), and some lanthanides☆

Gem-bis(disubstitutedphosphinyl)alkanes—II: Extraction of uranium(VI) with bis(di-n-hexylphosphinyl)methane

Bis-(disubstitutedphosphinyl)-alkanes—V: Solvation of uranyl nitrate by bis-(di-n-hexylphosphinyl) -methane, -ethane, -propane, -butane, and by tri-n-octylphosphine oxide☆

J.E. Mrochek

Papers

Bis-(disubstitutedphosphinyl)-alkanes—IV: Extraction of mineral acids, uranium (VI), and some lanthanides☆

Gem-bis(disubstitutedphosphinyl)alkanes—II: Extraction of uranium(VI) with bis(di-n-hexylphosphinyl)methane

Bis-(disubstitutedphosphinyl)-alkanes—V: Solvation of uranyl nitrate by bis-(di-n-hexylphosphinyl) -methane, -ethane, -propane, -butane, and by tri-n-octylphosphine oxide☆

Bis-(disubstitutedphosphinyl)-alkanes—VI: The interaction of bidentate phosphine oxides and tri-n-octyl phosphine oxide with water☆