Abstract
The extraction of the alkaline earths, excluding radium, by di(2-ethylhexyl)phosphate (DEHP) in benzene from 0·50 and 4·0 M sodium nitrate solutions has been examined as a function of pH and DEHP concentration. Curves with a characteristic maximum in the region of pH 5, similar to that already observed for strontium, were found in all cases. Log plots of E M = [ M] org [ M] aq . vs 3 pH gave a slope of +2 at low pH indicating exchange of M 2+ with 2H +. The relative extractability was Be ⪢ Ca > Mg > Sr > Ba from 4 M NaNO 3 and Be ⪢ Ca > Mg ≈ Sr > Ba from 0·5 M NaNO 3. Reagent concentration dependences at low pH where DEHP is in the acid dimer form (HDEHP) 2 indicate the following number of DEHP monomers associated with each metal atom: From 4·0 M NaNO 3: Be, ∼4; Ca, 5–6; Mg, uncertain; Ba, 6; and from 0·5 M NaNO 3: Be, uncertain; Ca, 4–5; Mg, 4–6; Ba, 4–6. The lower number always obtained at the lower reagent concentration and the higher number at the higher reagent concentration. The s ame association ratios and also indicated by the organic phase composition NaDEHP Σ DEHP at which maximum extraction occurs.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
