The vapor and liquid equilibrium data for N2 - G2H6- CO2 ternary system were measured at temperature 220.00 - 253.15 K and pressure 3.00 - 5.00 MPa. The experimental results were compared with the data calculated with equations of state PR
SRK and LKP. The experimental data were used to determine the optimal binary interaction coefficients kij for these equations of state. All of these equations gave satisfactory results with optimal kij. For all of 105 experimental points the arithmetic average error between experimental and calculated vaper composition data Δγ is 0.0064 for N2
0.0035 for C2H6
0. 0050 for CO2 and the error between experimental and calculated pressure data Δp ·p-1 is 1.7 % .