Membrane transport of organics. I. Sorption and permeation of carboxylic acids in perfluorosulfonic and perfluorocarboxylic polymer membranes

✍ Scribed by Romuald Wódzki; Jacek Nowaczyk

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 200 KB
• Volume: 63
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19970118)63:3<355::aid-app11>3.0.co;2-#

✦ Synopsis

Experimental studies have been made on the sorption and permeation of propionic (PA), acetic (AA), and formic (FA) acid in perfluorosulfonic Nafion, and perfluorocarboxylic Flemion membranes. The sorption isotherms show the increase of distribution coefficients K d Å C m /C e with the pK of acids, i.e., K d,PA ú K d,AA ú K d,FA . The transmembrane fluxes (J) and permeabilities (P) change their values in the same order for C e õ 0.1M and in the order J PA ú J FA ú J AA for higher concentrations. The differentiation of fluxes in single-component dialyses does not result in the effective separation of AA and PA during their competitive permeation through the Nafion-120 membrane. Under the same conditions, the Flemion membrane exhibits the preference toward propionic acid and transports PA and AA with the selectivity coefficient a PA AA equal to 1.5.