Evaluation of adsorption characteristics of HFO-1234yf refrigerant with different adsorbents

The adsorption refrigerator system with HFO-1234yf refrigerant (2,3,3,3-tetrafluoropropene) has a global warming potential of less than 4 and activated carbons (MaxsorbIII, MH-00), mesoporous silica (TMPS-2), and metal organic frameworks (MOF-177). We measured the adsorption isotherm under diverse temperature and pressure conditions experimentally, and evaluated the adsorption characteristics of these adsorbents. In this study, we designed an experimental apparatus using a volumetric method and measured the adsorption equilibrium uptake. The MaxsorbIII/HFO-1234yf pair has an adsorption uptake as high as 1.30 g-HFO-1234yf/g-ads at 40 °C and 300 kPa. The adsorption uptake is approximately equivalent to that of the MaxsorbsIII/HFC-134a pair. The experimental data of the adsorption/desorption isotherms show that there is no hysteresis for the studied pair. The experimental results were reproduced using the Dubinin–Astakhov model (D–A model). The D–A model fits the experimental results precisely within 7%. A diagram of the relationship between HFO-1234yf and MaxsorbsIII also generated the D–A model, and the adsorption uptake capacity between the adsorption and desorption steps was obtained as 0.07 kg-HFO-1234yf/kg-ads at 40 and 80 °C. The adsorption capacities of MOF-177, MaxsorbIII, TMPS-2, and MH-00 were evaluated under similar operating conditions to be 0.19, 0.08, 0.11, and −0.03 kg/kg respectively.