ISOTHERM ADSORPTION OF TOLUENE AND ZEOLITE Cu2+ZSM-5

Abstract

This paper presents the results of toluene adsorption isotherm in Cu2+ZSM-5 zeolite. To measure the adsorption isotherm, we used a system consisting of a universal high-vacuum adsorption unit and a differential modified microcalorimeter of the Tiana-Calve type DAK-1-1A connected to it, which directly gives quantitative and qualitative characteristics of the nature and forces of adsorption interaction. A correlation between the adsorption-energy characteristics was found and the molecular mechanism of toluene adsorption in Cu2+ZSM-5 zeolite was revealed in the entire filling area. It was determined that at low fillings, the isotherm rapidly rises, which indicates strong adsorption of two toluene molecules on Cu2+ cations. At the experimental temperature, it was determined that the volume occupied by a saturated toluene molecule is 0.102 cm3/g. This is 62% of the sorption volume of Cu2+ZSM-5 zeolite. It has been established that copper cations simultaneously interact with -electrons of benzene rings and with oxygen atoms of the lattice, hydrogen atoms of toluene molecules - with oxygen atoms of zigzag channels.