Modeling n-Pentane Hydroisomerization over a TsVM-Type Palladium-Containing Zeolite Catalyst

Abstract

Two methods to form the active surface of TsVM-type palladium-containing zeolite catalysts are studied. The substance of the active sites of these catalysts is palladium, which is introduced into TsVM-type zeolite by impregnation or ion exchange. Catalyst samples are tested in the n-pentane hydroisomerization reaction. A step mechanism of n-pentane hydroisomerization over palladium-containing zeolite is proposed, and its corresponding kinetic model is constructed. Kinetic experiments are carried out in a flow reactor with a 200-cm3 reaction zone. The pressure in the reactor varies from 10 to 30 atm, the temperature from 553 to 633 K, the hydrogen-to-(n-pentane + isopentane) molar ratio from 2 to 6, and the contact time from 0.05 to 2.0 h. The constants of the kinetic model, the variances of estimates of the constants, the variances of responses, the variances of observations, and the repeatability error variances are estimated by the maximum likelihood method from the results of the sequentially designed experiment. A precision kinetic model of n-pentane hydroisomerization over a TsVM-type palladium-containing zeolite catalyst has been built.