Solubilities in the system comprising acetonitrile (1) and hexadecane (2) have been reported in four publications. Schmid et al.¹ determined the upper critical solution temperature by the synthetic method. Rogalski and Stryjek² studied the mutual solubility of (1) and (2) between 298 to 418 K by an synthetic method. Stryjek et al.³ reported the mutual solubility of (1) and (2) between 298 K and 413 K at standard temperatures. McLure et al.⁴ measured of the upper critical temperature solution of components (1) and (2) as part of a study of the binary solubilities of acetonitrile + alkanes (C₅-C₁₈).

The upper critical solution temperature has been reported as 403.7 K,⁴ 417.2 K,¹ and 417.65 K.² The UCST of McLure et al.⁴ is rejected. The remaining values give an average recommended value of: UCST = 417.5 ±0.4 K. The corresponding critical solution composition has been reported as x_cl = 0.8358.²
All experimental values reported² have been approximated by an equation based on the scaling law (described in the introduction to this volume) for which the following parameters have been derived:

a₁ = 0.4482, a₂= 0.5602, b₁ = 3.0206, b₂ = -3.6064

(mean standard error of estimate was 0.0254).
For approximation x_cl and UCST from Rogalski and Stryjek² have been used. In the opinion of the evaluators, the mutual solubilities calculated by this equation may be treated as tentative. The results of calculations for the selected temperatures are presented in the following table. This relationship together with experimental points^2-3 are also presented in Fig. 12.