Isothermal Vapor–Liquid Equilibria of the Absorption Working Pairs (R1234yf + NMP, R1234yf + DMETrEG) at Temperatures from 293.15 K to 353.15 K

The vapor–liquid equilibria (VLE) data of R1234yf + NMP and R1234yf + DMETrEG were measured at the temperature range of 293.15–353.15 K in a dual cycle experimental apparatus. The thermodynamic consistency of the VLE data was checked with an area test. The VLE data were correlated by the nonrandom two-liquid model, and the results showed that they had a good agreement. The average relative deviation of pressure for R1234yf + DMETrEG was within 1.37% and its maximum was 3.51%; the average relative deviation of pressure for R1234yf + NMP was within 1.43% and its maximum was 3.65%. The results still showed that there was a large positive deviation between the binary system R1234yf + NMP and Raoul’s law, and the system R1234yf + DMETrEG exhibited a slight positive deviation to the ideal solution.