p–T–x Measurements for 1,1,1,2-Tetrafluoroethane (R134a) + N,N-Dimethylacetamide (DMA) and N-Methyl-2-pyrrolidone (NMP)

Abstract

The present study concerns p-T-x phase equilibria measurements involving two working fluid pairs (Refrigerant + Organic solvent) , namely 1,1,1,2-tetrafluoroethane (R134a) + N,Ndimethylacetamide (DMA) and , 1,1,1,2-tetrafluoroethane + N-methyl-2pyrrolidone (NMP), using the static-analytic method at temperatures varying between 303 and 353 K. The experimentally measured data were successfully correlated using the Peng-Robinson equation of state (PR-EoS) in combination with Huron-Vidal mixing rule, and the non-random two liquid activity coefficient model (NRTL), contrarily to the predictive Soave-Redlich-Kwong (PSRK) group contribution equation of state which failed to reproduce accurately enough such data.

Measurement and Correlation of Vapor–Liquid Equilibrium for R124 (1-Chloro-1,2,2,2-Tetrafluoroethane)-NMP (N-Methyl-2-Pyrrolidone) and R124-DMF (N,N-Dimethylformamide) Mixtures

“…It can be seen from Figure 2 that the deviation between p ref. 32 and p cal increases gradually with x 1 decreasing. Comparing p cal with p exp from Table 4 or Figure 2, the measurement data of this work is good in accordance with the data from ref 10.…”

“…Also, the maximum relative deviation between p ref. 32 and p cal is 8.03% at the point of x 1 = 0.54 and average relative deviation is 2.48%. It can be seen from Figure 2 that the deviation between p ref.…”

“…10 , p ref. 32 , p cal , and p exp with x 1 are shown in Figure 2 in which the curve of p cal is achieved by the five-parameter NRTL model given in ref 10. The maximum relative deviation between p exp and p cal is 3.76% and the average relative deviation is 1.87%.…”

“…In order to validate the reliability of measurement method mentioned above, the VLE data of binary mixture, R134a-DMAC, at 313.15 K were measured. Comparison of the measurement data and literature data , was listed in Table .…”

Thermodynamic Modeling of the Use of Alkane Mixtures as Working Fluids in Absorption Cycles

“…The operation of any absorption cycle‐based machines is also related to the nature of the refrigerant and the absorbent, their thermophysical and transport properties, and to the vapor‐liquid phase equilibria (VLE) occurring in different parts of these systems. Generally, VLE data are not always available or difficult to measure, hence the need for predictive models . However, the major problem is the choice of the most appropriate combination of activity and fugacity coefficient models.…”