Zeolite 4A: Heat capacity and thermodynamic properties

Abstract

The heat capacity of zeolite 4A (also known as LTA, Linde Type A and sodium zeolite A), in the temperature range from 37 to 311 K, is reported. The heat capacity shows no anomalies in this temperature range. Thermodynamic parameters, H, S and G, relative to their values at T = 0 K were derived. From these data, we find that zeolite 4A is stabilized by strong enthalpic interactions. Furthermore, its thermodynamic stability results from the strong Si-O and Al-O bonds in the primary building units, with bond strengths very close to those in other similar materials. © 2000 Éditions scientifiques et médicales Elsevier SAS.