Carbonic anhydrase (CA) has been immobilized on chitosan beads and has been tested for its activity using p-NPA. CA immobilized chitosan beads were further tested for targeted application of carbonation reaction to convert CO2 to CaCO3. It was observed that onset time for precipitation of CaCO3 was 40s for immobilized catalyst as compared to non-catalyzed system (100s). Mechanistic and kinetic aspects have been addressed for immobilized catalyst as well as free CA using p-NPA assay. K-m and V-max of the immobilized CA was observed to be 2.36mM and 0.54 mu moles/min/ml as compared to K-m and V-max of 0.87 mM and 0.93 mu moles/min, respectively, for free CA. Storage stability test was conducted up to 20 days and it was observed that at -20 degrees C, the Half Life Period (HLP) of immobilized CA was 216h as compared to 192 h for free CA whereas at 25 degrees C the HLP for immobilized and free CA was observed to be 456h and 408 h, respectively. (c) 2011 Elsevier Ltd. All rights reserved.