Chemisorption rate study by chromatography-$H_2$ over Pt/$SiO_2$

Abstract

The rates of chemisorption of hydrogen over a 2.52 w\% platinum on silica gel catalyst were measured by a chromatographic technique. The moment method and the isotope technique were used to determine the equilibrium and rate parameters. The pseudo-linearity of the system in the nonlinear range of isotherm was obtained by use of deuterium. The adsorption equilibrium constants and adsorption capacity decreased slightly, from $5.1\times10^{-5}$ to $4.1\times10^{-5}$ gmole/g, with increasing temperature from -20$^\circ$C to 30$^\circ$C. The rates of adsorption, or desorption were measured at given temperatures, -20$^\circ$C to 30$^\circ$C, and compared with those of the hydrogenation of ethylene. The rate of adsorption of hydrogen in this work is in good agreement with that of the hydrogenation of ethylene reported in literatures. The corresponding activation energy was 6 kcal/mole.