On the kinetics of rare-earth extraction into D2EHPA

Citation
A. Geist et al., On the kinetics of rare-earth extraction into D2EHPA, CHEM ENG SC, 54(12), 1999, pp. 1903-1907
Citations number
24
Categorie Soggetti
Chemical Engineering
Journal title
CHEMICAL ENGINEERING SCIENCE
ISSN journal
00092509 → ACNP
Volume
54
Issue
12
Year of publication
1999
Pages
1903 - 1907
Database
ISI
SICI code
0009-2509(199906)54:12<1903:OTKORE>2.0.ZU;2-S
Abstract
Extraction kinetics of rare-earth elements (La3+, Ce3+, Pr3+, Nd3+, Eu3+) i n nitric acid, thiocyanate and formate into D2EHPA (bis-2-ethylhexyl phosph oric acid ester, 0.05 kmol m(-3)) is studied in a stirred cell at pH = 2.1. Extraction rate is found to be limited by diffusion. Individual mass trans fer coefficients remain consistent for the metal ions investigated within a given aqueous system but are found to be approximately 25% higher in the f ormate system than in others. An explanation can be given by coupled diffus ion of cationic and anionic species. (C) 1999 Elsevier Science Ltd. All rig hts reserved.