Adsorbent coatings for heat pumping applications: Verification of hydrothermal and mechanical stabilities

This paper presents novel experimental methods for verification of both hydrothermal and mechanical stabilities of adsorbent coatings. Experiments have been carried out on zeolite-based coatings over aluminum substrates, prepared by a dip-coating technique developed at CNR-ITAE. Hydrothermal aging of several adsorbent coatings is ongoing. Adsorption and structural stability of some samples under test was successfully verified after 35000 aging cycles by isobars measurement and XRD analysis. Mechanical properties of coatings have been evaluated by applying different typologies of static and dynamic mechanical stresses. Results obtained have been compared with those achieved by subjecting adsorbent coatings prepared by Mitsubishi Plastic Incorporation (MPI) to the same characterization protocol. The comparison between the two types of coating returned that MPI coatings posses similar thermal stability and better mechanical strength than CNR-ITAE coatings.

► Novel methods for verification of hydrothermal and mechanical stabilities of adsorbent coatings are presented.
► Hydrothermal and mechanical stabilities were verified for ITAE and MPI adsorbent coatings.
► Hydrothermal stability of both ITAE and MPI coatings cycled 35000 times was successfully verified.
► MPI coatings presented better mechanical strength than ITAE coatings.