Feasibility Study of Cold Production Using Activated Carbon/CO2 Pair Amal Bel Haj Jrad 1* , Abdelaziz Zagnani 2 , Abdallah Mhimid 1 , Mohammed El Ganaoui 3 1 University of Monastir, National School of Engineering of Monastir, Laboratory of Thermal and Energetic Systems Studies, LR99ES31, 5019, Ibn Eljazzar Street, Monastir, Tunisia 2 Higher Institute of Sciences and Energy Technology, 2119 Tozeur Road, University of Gafsa, Tunisia 3 Laboratory of Studies and Research on Wood Material, Lorraine University, 186, rue de Lorraine, BP 54400, Longwy, France Corresponding Author Email: amalbhjm2@yahoo.fr https://doi.org/10.18280/ijht.370234 ABSTRACT Received: 26 March 2019 Accepted: 20 June 2019 The use of CO2 for adsorption cooling system is attractive and interesting. the production of solar cooling adsorption using activated carbon possesses many advantages: nontoxic and nonflammable natural refrigerant, with zero ozone depleting potentiel, negligible global warming potentiel for refrigeration and operating with solar thermal energy. A computer program written in Fortran language has been developed to provide us with the time-space evolution of temperature and average fluid content and to optimize the heat and mass transfers performance using activated-carbon/CO2 pair in Monastir city (Tunisia) during sorption phenomena. The main numerical results showed that activated carbon / methanol pair is more efficient than activated carbon / CO2 pair. COPs is less than 0.206 and 0.098 for activated-carbon/methanol and activated-carbon/CO2 pairs, respectively. The temperature is strongly related to mass desorbed. So, to improve the solar coefficient of performance COPs, it is necessary to have a large evaporation temperature and a low condensation temperature. Keywords: solar adsorption cooling, heat and mass transfers, activated carbon/CO2 pair, solar coefficient of performance (COPs) 1. INTRODUCTION Throughout Energy is an essential input to all economic activities, therefore access to energy is a vital component to ensure economic competitiveness and growth. The conventional fossil-fuel based energy structure comprises of fuel sources like coal, natural gas and petroleum. These sources are non-renewable in nature because their supply is limited and finite. In addition to being unsustainable, the fossil-fuel based energy structure is a major contributor to climate change and in some cases it proliferates adverse ecological impacts. The catastrophic effects caused by the overdependence of fossil based fuel sources have forced modern economies to consider renewable forms of energy. Renewable energy sources are infinite since they are naturally replenished. Adsorption cooling system is one of the most promising research topics in field of renewable energy. Common adsorbents, which have been studied in adsorption cooling applications: zeolite, silica-gel, and activated-carbon [1-7]. The activated carbon has been used with different refrigerants for low-temperature applications [8] for example activated-carbon/methanol [9, 10], activated- carbon/ammonia [11, 12], activated- carbon/ethanol [13, 14], activated-carbon/ /HFO-1234ze(E) [15]. During this work we are interested to the production of cold by adsorption using activated carbon / CO2 pair. The studies made so far are few, we note some work [16-20]. Animesh Pal et al. [16] have studied, experimentally, CO2 adsorption by a composite adsorbent using three models. They have showed that the Toth model is the most adequate. Skander Jribi et al. [17] studied the adsorption kinetics of CO2 on a microporous activated carbon powder of Maxorb III type. They found that the classical linear driving force (LDF) allows for better tuning of Toth and Duinin-Astakhov models. Vinod Kumar Singh et al. [18] have experimentally determined CO2 adsorption isotherms on three types of activated carbons. They found that specific cooling effect (SCEmax) and maximum coefficient of performance (COPmax) are respectively equal to 25.85 kJ / kg and 0.09, when heating temperature is 80 °C and evaporation temperature is 15 °C. Skander Jribi et al. [19] studied, numerically, the performance of four-bed adsorption refrigeration machine using activated carbon / CO2 pair. They found that with heating temperature of 95 °C and an optimal desorption pressure of 79 bar, the maximum coefficient of performance is 0.1. Wu Fan et al. [20] have studied, theoretically and experimentally, CO2 adsorption by five types of activated carbon to determine the maximum capacity of CO2 adsorption for each adsorbent. This study, also allowed that coefficient of performance is better when pore diameter of activated carbon is between 7 and 15 A. Nor Adilla Rashidi et al. [21] have studied, experimentally, CO2 adsorption by using a static volumetric instrument. They have determined CO2 adsorption isotherms using a various isotherm models. They found that Freundlich isotherm is the most adequate to the experimental data. Saha et al. [22] measured CO2 adsorption isotherms using activated carbon fiber of type A-20 and activated carbon powder of type Maxsorb III. The results show that that The Tóth and modified D−A isotherms are better fitting than that of the Langmuir and the D−A equations. International Journal of Heat and Technology Vol. 37, No. 2, June, 2019, pp. 625-632 Journal homepage: http://iieta.org/journals/ijht 625