Extractive distillation of propanol–water mixtures employing less‐soluble and sparingly soluble salts as separating agents

Extractive distillation of 1‐propanol and 2‐propanol from the respective organo‐aqueous mixtures employing less soluble (Na IO3, K2SO4, PbCl2) and sparingly soluble salts (Ca(OH)2, CaSO4, BaSO4, PbSO4, PbCO3) dissolved to saturation in the boiling liquid phase at atmospheric pressure has been examined. The 98% purification of 2‐propanol obtained with Ca++−, Pb++ and Ba++ salts suggests large perturbation of phase equilibria with relatively small salt concentrations (9 × 10−6 M for Pb++) on the 2‐propanol‐water system.