Vapor–liquid equilibria for R22 + N,N-dimethylformamide system at temperatures from 283.15 to 363.15 K

Binary vapor–liquid equilibrium p–T–x data were measured for R22 + DMF (N,N-dimethylformamide) system at temperature from 283.15 to 363.15 K by the circulating method. The experimental data are correlated by the Peng–Robinson–Stryjek–Vera equation of state using the Wong–Sandler mixing rule with NRTL model. The overall deviation of the pressure is 0.57%. The results reveal that the correlated data have a good agreement with the experimental ones. It is shown that the mixture has a large negative deviation from Raoultʹs law. The vapor–liquid equilibrium characteristics of the mixture are expressed in a log p − 1/T diagram and pressure–composition diagram for use in the analysis of an absorption refrigeration system.