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.
Hydrogen-bonding between HFCs and dimethyl ether
S Bobbo;L Fedele;R Camporese;
2001
Abstract
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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
