Journal of the Chinese Institute of Chemical Engineers, Vol.36, No.2, 135-145, 2005
Using aniline as an adductive agent for separation of an m-chlorophenol plus p-chlorophenol mixture
The experimental solid-liquid equilibrium data of ternary mixtures consisting of m-chlorophenol, p-chlorophenol, and aniline, and those of the constituent binary pairs were determined using the solid-disappearance method. The isomer mixture consisting of m-chlorophenol + p-chlorophenol exhibits one eutectic point at 276.0 K with 0.52 mole percentage of m-chlorophenol. The binary mixture of aniline + m-chlorophenol exhibits two eutectic points, 278.7 K and 257.2 K, at aniline compositions of 0.22 and 0.85, respectively, and one congruent point at aniline mole fraction of 0.5. And another pair of aniline + p-chlorophenol also exhibits two eutectic points, 286.2 K and 259.2 K, at aniline compositions of 0.28 and 0.87, respectively, and one congruent point at aniline mole fraction of 0.5. Ternary mixtures with designated mole ratios of m-chlorophenol to p-chlorophenol exhibit two eutectic points and one congruent point also at aniline mole fraction of 0.5. All the experimental SLE data were fitted by the empirical equation of Ott and Goates with an optimization technique. The results showed the equation of Ott and Goates represents the experimental data fairly well with the average absolute deviation of temperature less than 1.0 K. All the parameters were given and can be used for interpolation purpose. Based on the experimental data and the ternary phase diagram showing all the eutectic and congruent points, three conceptual feasible processes using aniline as an adductive agent for separating m-chlorophenol from p-chlorophenol are proposed.