Phthalic Anhydride → Naphthalene

Participants

Reaction Steps

In a process for separation of naphthoquinone from an aqueous slurry prepared by contacting, with an aqueous medium, a reaction mixture gas containing naphthoquinone and phthalic anhydride formed by a catalytic vapor phase oxidation of naphthalene, an improvement characterized in that naphthoquinone having a purity of higher than 95% in a form of a solution or a powder is separated by adjusting the pH of said aqueous slurry to 1.2 to 5 and extracting naphthoquinone with a straight or branched chain saturated hydrocarbon or cyclic saturated hydrocarbon at 60° to 110° C. under the condition of substantially dissolving phthalic acid in the aqueous phase and leaving resinous materials separated as a bottom phase and separating a solvent solution of naphthoquinone.

Provenance & Evidence