Determination of Differential Enthalpy and Isotherm by Adsorption Calorimetry

V. GARCIA-CUELLO, J.C.MORENO-PIRAJÁN , L. GIRALDO-GUTIÉRREZ, K. SAPAG, G. ZGRABLICH

RESEARCH LETTERS LIN PHYSICAL CHEMISTRY

Hindawi Publishing Corporation

Año: 2008 vol. 2008 p. 1 - 4

1687-6881

An adsorption microcalorimeter for the simultaneous determination of the differential heat of adsorption and the adsorption isotherm for gas-solid systems are designed, built, and tested. For this purpose, a Calvet heat-conducting microcalorimeter is developed and is connected to a gas volumetric unit built in stainless steel to record adsorption isotherms. The microcalorimeteris electrically calibrated to establish its sensitivity and reproducibility, obtaining K = 154.34 ± 0.23WV−1. The adsorption microcalorimeter is used to obtain adsorption isotherms and the corresponding differential heats for the adsorption of CO2 on a reference solid, such as a NaZSM-5 type zeolite. Results for the behavior of this system are compared with those obtained with commercial equipment and with other studies in the literature.