Thermodynamic analysis of promising biomass-derived activated carbons/CO₂based adsorption cooling systems

Adsorption systems are known as energy-saving and environmentally friendly technology, and porous adsorbent material is one of the critical elements of it. High-efficiency, compactness, and cost concern of these systems have motivated the preparation of functional carbons from waste biomass materials, which could be a promising adsorbent in the near future. In this paper, recently developed activated carbons (ACs) prepared from waste palm trunk and mangrove, possessing extremely high CO2 adsorption capacity, have been employed to estimate thermodynamic properties for understanding the performance of practical adsorption cooling systems. The thermodynamic properties such as heat of adsorption, specific heat capacity, enthalpy, and entropy are investigated with the variation of temperature and surface loading. The highest theoretical value of specific cooling effect (SCE) and the coefficient of performance is predicted for different operating conditions of cooling systems. It should be mentioned that SCE improvement compared to Maxsorb III is 52 % for C600 samples and 74 % for C500 samples, indicating studied four samples are promising. The presented analyses carry crucial importance and would provide a guideline to design practical biomass-derived ACs/CO2 based adsorption systems.