Work

Temperature-Jump Investigation of Adsorption/Desorption Kinetics at Methylated Silica/Solution Interfaces

Year: 1995

Type: article

Abstract: A temperature-jump relaxation technique is used to monitor reversible adsorption/desorption kinetics at the reversed-phase C1-silica/solution interface. A Joule-discharge is used to heat a packed bed of trimethylchlorosilane-derivatized silica gel on a microsecond time scale. Single-exponential relaxation kinetics are observed for adsorption of an ionic fluorescent probe, 1-anilino-8-naphthalene sulfonate, to a C1-silica surface from methanol:water solution. The relaxation rate increases with concentration of solute in solution, which shows that adsorption kinetics are detectable in the relaxation. The adsorption rate of the ionic probe is slower than diffusion-controlled, exhibiting significant influence over the adsorption equilibrium constant. Furthermore, the adsorption rate of N-phenyl-1-naphthylamine is indistinguishable from the diffusion limit, indicating a negligible barrier to adsorption for this neutral species.

Source: Analytical Chemistry

DOI: 10.1021/ac00115a012

Authors: F. Y. Ren, S. W. Waite, J. M. Harris

Institution: University of Utah

Language: English

Topic: Analytical Chemistry and Chromatography

Subfield: Spectroscopy

Field: Chemistry

Domain: Physical Sciences

Open Access status: green

Funder: U.S. Department of Energy

Award: NEW GRANT - TIME RESOLVED ANALYTICAL METHODS FOR LIQUID/SOLID INTERFACES P.I. - JOEL M. HARRIS