New composite sorbents of water and methanol “salt in anodic alumina”: Evaluation for adsorption heat transformation

• Composite sorbents based on (LiCl, CaCl2) in anodic alumina (AA) are synthesized.
• Texture parameters of the AA layers are superior to those presented in literature.
• Efficient heat transfer in the AA/Al sandwich leads to fast ad-/desorption process.
• Good potential of the new composite sorbents for heat transformation is revealed.

Development of new adsorbents of water and methanol specialised for AHT (adsorption heat transformation) can essentially advance this emerging low-carbon technology. This paper addresses the synthesis of novel composite sorbents based on an AA (anodic alumina) layer impregnated with hygroscopic salts, and the study of their ability to sorb water and methanol vapours. This work consists of the three parts: (1) synthesis and comparison of AA/Al sandwiches obtained with various electrolytes (sulphuric, oxalic, and phosphoric acids); (2) preparation of salt/AA composites (salt = CaCl2 and LiCl) and study of their sorption equilibrium and dynamics with water and methanol vapours; and (3) evaluation of the new sorbents feasibility for AHT applications. The results obtained show that a) the new AA-based composites could be interesting for making compact AHT units with short working cycles, and b) still more R&D are necessary for further progress towards practical implementation of the new sorbents.

Figure optionsDownload as PowerPoint slide