Chitosan reinforced boehmite nanocomposite desiccant: A promising alternative to silica gel

Abstract This paper describes the synthesis and performance evaluation of a granular solid desiccant composite synthesized through a sol-gel process at atmospheric pressure and ambient temperature. The composite desiccant essentially comprises of a biopolymer template, chitosan, and nanoscale boehmite particles embedded on the fibrils of the biopolymer. The chitosan fibers not only help in the formation of boehmite nanoparticles but also act as a reinforcing agent and enable the formation of sand like granules upon aging and drying. The composite showed promising ability to dehumidify the moist air. The desiccant was characterized in detail to study its textural, morphological and chemical properties. The results revealed the formation of crystalline, nanostructured composite with moisture adsorption capacity more than its self-weight (>1.5 g/g at 55–65% RH). The high moisture removal capacity, ease of synthesis and scale-up, and green synthesize approach would make the material a sustainable substitute for silica gel.