The Kinetics of Propane Adsorption on Platinum in Hydrofluoric Acid

As a first stage in the investigation of the electrochemical oxidation of saturated hydrocarbons on platinum in acid electrolytes, the rate of adsorption of propane on a smooth platinum electrode was studied at 90°C in 37 mole % HF. Using an all‐PTFE apparatus and single linear voltage sweep techniques, the surface coverage by hydrocarbon species was measured as a function of adsorption time and potential. The steady‐state coverage resulting from propane adsorption shows a sharp maximum at 0.2v ( vs. rhe). The amount of the most electrochemically active species is highest at 0.3v. The adsorption rate follows Langmuir kinetics with a third‐order dependence on free surface. The rate constant has been measured for 0.2 and 0.3v at 90°C.