Extraction of lanthanoids by liquid surfactant membranes

Journal Article · Thu May 01 00:00:00 EDT 1986 · Sep. Sci. Technol.; (United States)

DOI:https://doi.org/10.1080/01496398608058375· OSTI ID:5502680

Teramoto, M; Sakuramoto, T; Koyama, T; Matsuyama, H; Miyake, Y

Separation and concentration of lanthanoids such as La/sup 3 +/, Nd/sup 3 +/, Sm/sup 3 +/, Eu/sup 3 +/, Gd/sup 3 +/, Dy/sup 3 +/, and Yb/sup 3 +/ were carried out using liquid surfactant membranes containing 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester as a carrier. Under the condition of sufficiently high distribution ratio, more than 98% of these metal ions was extracted within 5 min even if the volume ratio of W/O emulsion to the external aqueous phase was as low as 1/32. The ratio of the concentration of metal ions in the internal aqueous phase to that in the external feed phase reached about 50,000 within 20 min. In the conventional solvent extraction of Yb/sup 3 +/, the aggregates of metal-carrier complexes, which were insoluble in the organic membrane phase, were formed at high loading ratio. In the extraction of Yb/sup 3 +/ by liquid surfactant membranes, however, formation of such aggregates was suppressed because both extraction and stripping occurred simultaneously on both sides of the membranes. The rate of interfacial reaction between lanthanoids and the carrier was remarkably reduced by the presence of the emulsifier, and the forward reaction rate was represented by r/sub f/ = k/sub f/(Ln/sup 3 +/)((HR)/sub 2/)/sup 3//(H/sup +/)/sup 3/ where ((HR)/sub 2/) is the concentration of the dimer of the carrier. The rate of the extraction by liquid surfactant membranes was satisfactorily simulated by a proposed permeation model, i.e., a multilayer shell model.

• Research Organization: Kyoto Institute of Technology, Japan
• OSTI ID: 5502680
• Journal Information: Sep. Sci. Technol.; (United States), Journal Name: Sep. Sci. Technol.; (United States) Vol. 21:3; ISSN SSTED
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400105* -- Separation Procedures
400301 -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
DATA
DIMERS
DYSPROSIUM
EFFICIENCY
ELEMENTS
ESTERS
EUROPIUM
EXPERIMENTAL DATA
EXTRACTION
FLUIDS
GADOLINIUM
INFORMATION
KINETICS
LANTHANUM
LIQUIDS
MATHEMATICAL MODELS
MEMBRANES
METALS
NEODYMIUM
NUMERICAL DATA
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PERFORMANCE
PHOSPHONIC ACIDS
RARE EARTHS
REACTION KINETICS
SAMARIUM
SEPARATION PROCESSES
SOLVENT EXTRACTION
SOLVENT PROPERTIES
SURFACTANTS
YTTERBIUM