Evaluation of R-1132(E)/32 mixtures: pVT properties, critical parameters and binary interaction parameters.

R-32 (difluoromethane) exhibits exceptional performance as a refrigerant, making it the dominant refrigerant in domestic heat pumps across Japan. Its high Global Warming Potential (GWP), however, drives efforts to find environmentally friendly alternatives, including mixtures. Refrigerant mixtures that include R-32 often reduce environmental impact but typically lower the coefficient of performance (COP) compared with pure R-32 systems. R-1132(E) (trans-1,2- difluoroethylene) offers properties similar to R-32 with a lower GWP. Industry interest in the R-1132(E)/32 mixture stems from the limited production capacity and technical challenges associated with R-1132(E). This study investigates the thermophysical properties of the R-1132(E)/32 mixture. The evaluation includes pressure-volume-temperature (pVT) behaviour over temperatures ranging from 230 to 370 K and the critical parameters. Using these experimental data, the binary interaction parameters of this mixture are determined. These findings contribute to understanding the mixture's behaviour and support its assessment as a refrigerant in heat pump systems.