Synthesisation of CaCl2-in-zeolite adsorbents for water based isotherms and kinetics study

• Main Author: Lee, Geoffery Gan He
• Other Authors: Anutosh Chakraborty
• Format: Final Year Project
• Language: English
• Published: 2019
• Subjects: DRNTU::Engineering::Mechanical engineering
• Online Access: http://hdl.handle.net/10356/77650
• Institution: Nanyang Technological University

Climate changes in recent decades have brought about more attention towards renewable energy systems and technology that releases less greenhouse gases, such as hydrochlorofluorocarbons, into the environment, and reduced energy wastages. Hence, the adsorption chiller is perceived as one of the solutions to the problem of climate change and thus giving the notion that it will eventually replace conventional vapour compression cycle chillers. To aid in this area of development, adsorbents such as the AQSOA zeolite are studied based on their adsorption equilibrium and kinetic behaviours in order to improve the efficiency and cooling capacity for adsorption chillers. Calcium Chloride is impregnated to improve water absorbency characteristics of the AQSOA zeolite. This newly synthesized composite adsorbent is then assessed for their uptake characteristics and surface properties using thermogravimetric analysis (TGA), scanning electron microscopy (SEM), N2 adsorption and lastly, measured for their water uptake at temperatures of first 25°C, then 35°C, followed by 45°C and 60°C. Result analysis using the TGA, N2 adsorption and water sorption test show results that for the AQSOA Z05 zeolite, with an increase in the amount of calcium chloride impregnated, there is a trend of increasing water uptake performance. Re-impregnation of the composite adsorbent improves the uptake performance even further, with re-impregnation of calcium chloride providing an increase of as much as three times the original AQSOA Z05 at 1kPa. These findings may be useful in chiller applications, as a higher uptake signifies a more efficient and smaller footprint of chiller designs.