The effect of porous support composition and operating parameters on the performance of supported liquid membranes
Factors, such as porous support composition and operating parameters, that influence the performance of supported liquid membranes (SLMs) were investigated. SLMs of varying porous support compositions and structures were studied for the transport of metal ions. A microporous polybenzimidazole support was synthesized and prepared in the form of an SLM. This SLM containing the selective extractant di-(2-ethylhexyl)phosphoric acid was evaluated for the transport of copper and neodymium. Dramatically improved performance over that of commercially available membranes was found in tests for removing the metal ions from solution. Metal ion transport reaches near completion in less than 3 hours, whereas Celgard-polypropylene and Nuclepore-polycarbonate reaches only 50% completion even after 15 hours. The transport driving force for acidic extractants is a pH gradient between the feed and strip solutions. Polybenzimidazole, an acid- and radiation-resistant polymer, has two protonatable tertiary nitrogens per repeat unit that may help sustain the pH driving force. Another factor may be the ability of the polybenzimidazole to hydrogen bond with the extractant. Transport through the flat-sheet SLMs were tested using a unique cell design. Countercurrent flow of the feed and strip solutions was established through machined channels in half-cell faceplates that are in a spiral, mirror-image pattern with respect to each other, with the flat-sheet SLM interposed between the two channeled solutions. 7 refs., 14 figs.
- Research Organization:
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- Sponsoring Organization:
- DOE/DP
- DOE Contract Number:
- W-7405-ENG-36
- OSTI ID:
- 6235612
- Report Number(s):
- LA-12027-MS; ON: DE91007313
- Country of Publication:
- United States
- Language:
- English
Similar Records
Influence of membrane solvent on strontium transport from reprocessing concentrate solutions through flat-sheet-supported liquid membranes
Supported extractant membranes for americium and plutonium recovery
Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
36 MATERIALS SCIENCE
POLYMERS
PERMEABILITY
SUPPORTED LIQUID MEMBRANES
PERFORMANCE
ACTINIDES
BENZIMIDAZOLES
CHEMICAL COMPOSITION
MEMBRANE TRANSPORT
POROSITY
AZOLES
ELEMENTS
HETEROCYCLIC COMPOUNDS
IMIDAZOLES
MEMBRANES
METALS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
400105* - Separation Procedures
360603 - Materials- Properties