SAPO-34 coated adsorbent heat exchanger for adsorption chillers. (5th May 2015)

• Record Type: Journal Article
• Authors: Freni, Angelo; Bonaccorsi, Lucio; Calabrese, Luigi; Caprì, Angela; Frazzica, Andrea; Sapienza, Alessio
• Is Part Of: Applied thermal engineering. Volume 82(2015:May)
• Page Start: 1
• Page End: 7
• Publication Date: 2015-05-05
• Subjects: Adsorption cooling -- Coating -- SAPO 34 -- Coated adsorber; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2015.02.052
• Languages: English
• ISSNs: 1359-4311

Abstract

Abstract: In this work, adsorbent coatings on aluminum surfaces were prepared by dip-coating method starting from a water suspension of SAPO-34 zeolite and a silane-based binder. Silane-zeolite coatings morphology and surface coverage grade were evaluated by scanning electron microscopy. Adhesive and mechanical properties were evaluated by peel, pull-off, impact and micro-hardness tests, confirming the good interaction between metal substrate, binder and zeolite. Adsorption equilibrium and kinetics of water vapour adsorption on the adsorbent coating were studied in the range T = 30–150 °C and pH2 O = 11 mbar using a CAHN 2000 thermo-balance. It was found that, in the investigated conditions, the organic binder doesn't affect the water adsorption capacity and adsorption kinetics of the original SAPO-34 zeolite. Subsequently, the zeolite coating was applied on a finned flat-tubes aluminum heat exchanger realizing a full-scale AdHEx with an uniform adsorbent coating 0.1 mm thick and a metal/adsorbent mass ratio = 6. The cooling capacity of the realized coated AdHEx was measured by a lab-scale adsorption chiller under realistic operating conditions for air conditioning applications. The coated AdHEx produced up to 675 W/kgads specific cooling power with a cycle time of 5 min. Adsorption stability of the coated adsorber subjected to 600 sorption cycles was successfully verified. Highlights: Adsorbent coatings on aluminum surfaces were prepared by dip-coating method. Silane-zeolite coatings morphology, and mechanical properties were studied. The zeolite coating was applied on a finned flat-tubes aluminum heat exchanger. The coated AdHEx was tested in a lab scale adsorption chiller.