Experimental study on the solubility of Propylene (R1270) in PAG, POE and AB lubricants

• The solubility of R1270 in PAG, POE and AB lubricants was measured and compared. • The NRTL model was applied to correlate the experimental solubility data. • R1270 exhibited the highest solubility in PAG lubricants. R1270 is considered a suitable alternative to chlorodifluoromethane (R22) and 1,1,1,2-tetrafluoroethane (R134a) due to its environmentally friendly nature and comparable thermophysical properties . In compression refrigeration systems , the used lubricants need to be matched with alternative refrigerants and exhibit appropriate solubility. Therefore, in this study, the solubility of R1270 in three lubricants: polyalkylene glycol (PAG), polyolester (POE), and alkybenzene (AB) was measured using the isochoric saturation method at temperatures ranging from 283.15 to 323.15 K. Henry's constant was calculated to intuitively compare the solubility of R1270 in the three lubricants. The results indicate that R1270 is miscible with PAG46, POE68, and AB100 lubricants across the entire test temperature range, with the highest solubility observed in PAG46, while POE68 and AB100 exhibit similar solubility characteristics. Subsequently, the non-random two-liquid (NRTL) activity coefficient model was applied to correlate the experimental solubility data. The significance of this study is to provide a reference for the selection of suitable lubricants for R1270 in various applications.