The adsorption heat of ethylamine, n-pentane and ethanol was measured based upon the determination of adsorption isothemis at different temperatures on high silica FAU type zeolite with perfect Si-O framework. Calculated with Clapeyron - Clausious equation, the isosteric heat of adsorption Qst (C) (adsorption heat at certain coverage, which is defined as the numbers of adsorbed melecules per unit cell) and average isosteric heat of adsorption Qst^* (the average adsorption heat with various coverage determined in a certain temperature range) were obtained for the adsorbates investigated. △ H1-the difference of Qst^* and △Hv(the heat of vaporization of certain adsorbate), was defined as interaction strength for characterizing the interaction between Si-O framework of the zeolite and the adsorbed organic compound. The order of △H1 for the adsorbed organic compounds is as follows: △ H1(ethylamine)>△H1(n-pentane)>>△ H1(ethanol), which is consistent with the order of AT value (affinity index, was defined as AT=Td-Tb, where Td is the temperature of the weight loss peak of the DTG curve, and Tb is the boiling point of a certain adsorbate). The strong interaction between Si-O framework and the adsorbed ethylamine, which was observed from the desorption behavior on FAU zeolite, is thermodynamically proved in this study by the high interaction strength of △H1(ethylamine) determined quantitatively.

Key words: ADSORPTION, ETHYLAMINE, PENTANE, ETHANOL, HIGH SILICA ZEOLITES, ADSORPTION ISOTHERM, ADSORPTION HEAT