Electrosorption of vinyltriphenyl and propargyltriphenylphosphonium cations from methanolic solutions at the dropping and hanging mercury drop electrodes

Abstract

Recelled February 19, 1986 ANASTASIA CHRISTODOULOU, ANASTOS ANASTOPOULOS. and DEMETRIOS JANNAKOUDAKIS. Can. J. Chem. 64,2279Chem. 64, (1986. The interfacial behaviour of vinyltriphenyl and propargyltriphenylphosphonium cations at the mercury electrode -methanolic solution interface is studied by phase selective ac polarography using dropping Hg electrodes of short ( S 5 s) and long (=20 s) drop times and the hanging Hg drop electrode.The various adsorption parameters are determined on the basis of non-ionic adsorption isotherms involving capacitance data independent as well dependent on time.ANASTASIA CHRISTODOULOU, ANASTOS ANASTOPOULOS et DEMETRI~S JANKAKOUDAKIS. Can. J. Chem 64, 2279Chem 64, (1986. Faisant appel a la polarographie a ca et a phase sklective et utilisant soit des Clectrodes a goutte tombante de mercure avec des temps de chute court ( 5 5 s) et longs (=20 s) soit une electrode i goutte pendante de mercure, on a etudiC le comportement interfacial des cations vinyltriphbnyl-et propargyltriphenyl-phosphonium.On a dktermink les divers paramhtres d'adsorption en se basant sur des isothermers d'adsorptions non-ioniques impliquant des donnCes de capacitance tant indkpendantes que dependantes du temps.[Traduit par la revue]

Is the Free Energy Change of Adsorption Correctly Calculated?

“…In fact, according to Chritodoulou et al, 21 the Flory-Huggins isotherm (eq 20) can be rearranged to ln…”

“…The original Flory−Huggins isotherm accounts for the effect of the surface coverage on adsorption θ e false( 1 − θ e false) n FH exp false( −2 n FH α FH θ e false) = K FH C e in which K FH is the so-called Flory−Huggins equilibrium constant, n FH is constant, and α FH is an effective coefficient indicating the interaction between adsorbed molecules. It can be seen that eq turns into a Frumkin-type isotherm (eq ) at n FH = 1.…”

“…In fact, according to Chritodoulou et al, the Flory−Huggins isotherm (eq ) can be rearranged to ln θ e C e = ln K FH + 2 n FH α FH θ e + n FH ln false( 1 − θ e false) …”