Isobaric Vapor Liquid Equilibria for (Water+1-Methoxy-2-propanol), (Water+2-Methoxy-1-propanol), and (1-Methoxy-2-propanol+2-Methoxy-1-propanol) at 101.3 kPa

Isobaric vapor liquid equilibria (VLE) data were measured at 101.3 kPa for three binary systems (water + 1-methoxy-2-propanol), (water + 2-methoxy-1-propanol), and (1-methoxy-2-propanol + 2-methoxy-1-propanol) by using a modified Rose-Williams still, in which both vapor and liquid phases circulate continuously. Positive deviations and azeotropic behaviors were found in systems (water + 1-methoxy-2-propanol) and (water + 2-methoxy-1-propanol), while a negative deviation was found in the system (1-methoxy-2-propanol + 2-rnethoxy-1-propanol). All of the experimental VLE data for the three binary systems were tested and verified to be thermodynamically consistent by the Herington area test and Van Ness point test. The nonideality of the vapor phase was corrected by the Hayden O'Connell method. The experimental isobaric VLE data were correlated'by using the universal quasichemical (UNIQUAC) and nonrandom two-liquid (NRTL) models, and the binary interaction parameters for the two models were reported. Results showed that both models correlated the experimental data with good accuracy.