Hydrogen-bonding between HFCs and dimethyl ether

Analysis of VLE data for HFC+dimethyl ether (RE170) systems always show a strongly negative deviation from Raoult's law, as effect of H-bonding between RE170 and HFC. This H-bonding was quantified through the excess Gibbs energy (gE) function obtained from the VLE data correlation by selected equations of state (EoS). Binary systems with the following HFCs: R125, R134a, R236ea, R236fa, and R227ea were included in the study. Two HCFCs (R22 and R142b) were also considered. The gE values for the HFCs systems were split into two parts representing the H-bonding and the physical interaction, as given by systems formed by the same HFCs with propane (R290) as a homomorph of RE170. It is worth noting that HFC+R290 systems show strong positive deviations from Raoult's law with the formation of positive azeotropes, due to the strong repulsive forces between HFCs and R290.