Synthesis of SAPO-34 zeolite filled macrocellular foams for adsorption heat pump applications: A preliminary study

In this work, a new approach for an innovative adsorber is presented, not necessarily alternative to the zeolite coated absorbers, based on the use of composite SAPO-34 filled silicone foams that can improve the adsorption surface area without altering the adsorption pump dynamic performances. Flexible, semirigid or rigid zeolite/silicone foams, obtained with different zeolite amount, were produced ranging from mixed open/closed cell configurations to closed cell configurations. The cells are homogeneously distributed along the foam cross section, consequently mechanically unstable regions were not identified. Adsorption measurements evidenced that the adsorbent foams have effective adsorption capacity without obstruction of the porous structure of the pure zeolite, indicating its potential application in adsorption heat pump. In particular composite foam with 70 wt.% of zeolite evidenced a water adsorption of 21.6%. Considering that SAPO-34 powder evidenced an adsorption of 31.7% thus indicating that above 96% of zeolite in the foam is active and the zeolite porosity was maintained also in silicone binder as matrix.