The stability of zeolite coatings grown on metal supports for heat pump applications

Abstract

The utilization of zeolite coatings synthesized on metal substrates may eliminate the heat and mass transfer limitations present in systems such as adsorption machines which provide heating and cooling effects. In this study, the stabilities of the zeolite 4A coatings, prepared by using a recently developed method that allows the controlled deposition of the zeolite on the substrate, are tested for various amounts of zeolite synthesized on stainless steel plates. The thermal and mechanical stabilities of the coatings are determined by the application of consecutive heating and cooling cycles and ultrasonic treatments, respectively. Although ultrasonic treatments resulted in relatively higher mass losses, the stabilities of the zeolite coatings synthesized on stainless steel plates are observed to be only moderately affected by the very rapid and consecutive heating and cooling cycles applied. No difficulty is observed for the desorption of water vapor out of the zeolite layer for any of the samples investigated in this study.