The critical temperatures and critical pressures of some examples of (a polar substance + a non-polar substance) and of (a polar substance + another polar substance)

Abstract

Measurements of the critical temperature and critical pressure of [ x C 5 H 11 OH + (1 − x {CH 3 CH(CH 3 )CH(CH 3 )CH 3 or CH 3 CH(OH)CH(CH 3 )CH 3 or CH 3 COCH(CH 3 )CH 3 or CH 3 CH(CH 3 )OOCCH 3 or CH 3 CH(CH 3 )CH 2 OOCCH 3 or CH 3 CH(CH 3 )CH 2 CH 2 OOCCH 3 }] were made by visual observation of the disappearance and reappearance of the meniscus. The results are presented on p ( T ), T ( x ), and p ( x ) planes. None of the mixtures forms an azeotrope in the critical region. The deviations of the critical properties from linearity in the mole fraction are also presented. The interaction parameter between pairs of unlike molecules in the mixture have been estimated from the experimental values. The experimental uncertainty in T c and p c is within ± 0.5 K and ±0.03 MPa, respectively.