Measurements and Correlations of cis-1,3,3,3-Tetrafluoroprop-1-ene (R1234ze(Z)) Saturation Pressure

In the recent past, several studies have been devoted to find substances, for example, blowing agents, propellants, and refrigerants, with low global warming potential (GWP). Primarily because of the increasing amount of taxes, laws, and regulations being proposed and implemented by various government bodies related to high-GWP compounds. Recently, great attention has been put on fluorinated propylene isomers (HFO) as potential new and replacement refrigerants with low GWP. The two most studied HFOs are R1234ze(E) (trans-1,3,3,3-tetrafluoroprop-1-ene; CF3CH=CHF), with a GWP of 6 relative to carbon dioxide1 based on a 100-year timeframe, and R1234yf (2,3,3,3-tetrafluoroprop-1-ene; CF3CF=CH2), with a GWP of 4 relative to carbon dioxide2 over the same timeframe. R1234yf is considered as a potential replacement of R134a in automotive applications3. One other fluorinated propene isomer being considered is cis-1,3,3,3-tetrafluoropropene (R1234ze(Z), CHF=CHCF3, CAS 29118-25-0). The GWP of R1234ze(Z) has not been reported; however, the authors expect its value to be approximately 10 or less, i.e., the same order of magnitude as R1234ze(E). Higashi et al.4 report the critical temperature, pressure, and density and nineteen vapour pressure measurements over the temperature range 310 K to 420 K. Continuing investigations of HFO isomers by the authors, here they present new vapour pressure data for R1234ze(Z) over the an important temperature range from 230 K to 380 K from two different laboratories, i.e. the Thermodynamic Properties Laboratory of the Istituto per le Tecnologie della Costruzione del Consiglio Nazionale delle Ricerche (ITC-CNR) and the Dipartimento di Ingegneria Industriale e Scienze Matematiche of the Università Politecnica delle Marche (UnivPM). In addition, they provide an estimate of its normal boiling point temperature (NBP) and two vapour pressure correlations.