GB107961A - Improvements in the Process for the Separation of Cresols. - Google Patents

Abstract

107,961. Darzens, G. A. July 11, 1916,. [Convention date]. Cresols.-The three cresols are separated from mixtures thereof by forming addition compounds of m - cresol with anhydrous sodium acetate, and of p - cresol with anhydrous oxalic acid, separating these crystalline compounds, and decomposing them by water. The process may be carried out by diluting the mixture of cresols with an anhydrous solvent (ligroin, benzene, toluene, xylenes, chloroform, chlorbenzene, hydroaromatic compounds, &c.), adding oxalic acid, separating the solid p-cresol addition product and decomposing it by steam-distillation in the presence of sufficient water, treating the residual mixture of o - and m - cresol with sodium acetate, separating the solid m - cresol addition product and decomposing it by distillation in the presence of sufficient water; the residue consists mainly of o - cresol. The order of the treatments with oxalic acid and sodium acetate may be reversed. If desired, the bulk of the ocresol may be removed by a preliminary fractional distillation in vacuo. The aqueous solutions of oxalic acid and sodium acetate mav be evaporated to recover these reagents. The m - cresol separated by the above process gives a high yield of trinitro - m - cresol on nitration. The Specification, as open to inspection under Sect. 91 (3) (a), refers to the separation of cresols by forming addition products generally. This subject-matter does not appear in the Specification as accepted.