@article{oai:nagasaki-u.repo.nii.ac.jp:00015873, author = {鹿川, 修一 and 岡, 宏 and 中森, 一誠}, issue = {5}, journal = {長崎大学工学部研究報告, Reports of the Faculty of Engineering, Nagasaki University}, month = {Dec}, note = {The heats of adsorption of three isomers of xylene on the Pt-SiO2-Al2O3 isomerization catalyst have been measured by gas chromatographic technique with hydrogen as a carrier gas in the temperature range of 340 to 460℃, and compared with those obtained from the measurement of reaction kinetics by using a fixed bed flow reactor. A retention volume of xylene varied with an amount of sample injected and with a contact time (amount of catalyst packed/flow rate of carrier gas). Under the condition of a constant contact time, an apparent heat of adsorption was determined from the temperature dependency of the retention volume obtained, by extrapolating to infinitesimal samples. The apparent heat of adsorption thus obtained was incrgased with contact times, which may arise from the extent of reaction. In order to eliminate the extent of reaction, the extrapolation of the apparent heat of aqsorption was made to infinitesimal contact times. The heats of adsorption of ο-, m-, and p-xylene for infinitesimal contact times were found to be 7.9 ± 2.1, 6.2 ± O.4, and 5.9 ± O.9 kcal/mole, respectively. On the other hand, from the analysis of reaction kinetics, the xylene isomerization was verified to consist of six interconversion reactions among three isomers, each of which follows the rate equation of Langmuir-Hinshelwood type, and the heats of adsorption of these isomers were determined from the temperature dependency of adsorption equilibrium constants. Taking the error into account, both heats of adsorption were in good agreement. It should be emphasized that on the measuremeht of a heat of adsorption during course of reaction by gas chromatographic technique the effect of reaction must be eliminated., 長崎大学工学部研究報告, (5), pp.149-153; 1974}, pages = {149--153}, title = {ガスクロ法による反応中の吸収特性の測定 I.Pt - Si02 - Al2 O3 異性化触媒へのキシレンの吸収熱}, year = {1974} }