Electrosorption of 1-butanol at the mercury-electrolytic solution interface in the presence of specifically adsorbed anions. A test of the basic Frumkin model

Journal Article · Mon Mar 01 04:00:00 EST 1993 · Langmuir; (United States)

DOI:https://doi.org/10.1021/la00027a040· OSTI ID:5989304

Baikerikar, K G; Hansen, R S ^[1]

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1. Ames Lab., IA (United States)

The mercury-electrolytic solution interfacial tension [gamma] was measured at 25[degrees]C as a function of 1-butanol activity a[sub A] and polarization E measured against a saturated NaCl calomel electrode for 1-butanol reduced concentrations c/c[sub 0] from 0 to 0.5 at 50-mV intervals for 0.10 M electrolytes HClO[sub 4], KCl, KBr, and KI. For KCl, KBr, and KI the function ln (a[sub A]/c[sub 0]c) was found to vary linearly with c/c[sub 0] within experimental error; parameters for the linear functions are given. For HClO[sub 4], values of ln(a[sub A]c[sub 0]/c) were comparable to those for KCl for c/c[sub 0] > 0.2 but were irreproducible for lower values of c/c[sub 0]. Plots of [gamma](c/c[sub 0]E) with E referred to the electrocapillary maximum of the 0.10 M HClO[sub 4] and KCl base solutions (-0.477.V vs SSCE in both cases) for a given c/c[sub 0] for all four electrolytes were indistinguishable for E < -0.35 V, but as E became more positive than -0.35 V first the [gamma](c/c[sub 0],E) curve for KI, then that for KBr, then that for KCl deviated negatively from that for HClO[sub 4]. As c/c[sub 0] increased, the polarization required for divergence also increased. The basic Frumkin model for regular localized monolayer electrosorption was used to develop a master curve of [pi]/[Gamma][sub m]RT vs ln Ba[sub A] with parameters [Gamma][sub m]RT, [alpha], B[sub 0], C[prime], and E[sub N] taken as the same for all electrolytes. These parameters and experimental values of [gamma](0,E) permit determination of B(E)/B[sub 0], so that experimental points can be compared with the master curve. Results for E [le] E[prime] -0.1 with E[prime] = 0.500, 0.300, and 0.000 V for KCl, KBr, and KI, fell quite close to the master curve for all values of a with values of [pi][Gamma][sub m]RT deviating from it by more than 0.04 quite rare and no systematic pattern to deviations apparent. 23 refs., 5 figs.

• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 5989304
• Journal Information: Langmuir; (United States), Journal Name: Langmuir; (United States) Vol. 9:3; ISSN LANGD5; ISSN 0743-7463
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400400* -- Electrochemistry
99 GENERAL AND MISCELLANEOUS
990200 -- Mathematics &amp; Computers
ADSORPTION
ALCOHOLS
BUTANOLS
CHEMISTRY
ELECTROCHEMISTRY
ELECTRODES
ELECTROLYTES
ELEMENTS
HYDROXY COMPOUNDS
MATHEMATICAL MODELS
MERCURY
METALS
ORGANIC COMPOUNDS
SORPTION
SURFACE PROPERTIES
SURFACE TENSION