The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 02, 1989
Filed:
Oct. 29, 1986
Roger Cocco, Saint-Symphorien d'Ozon, FR;
Rhone-Poulenc Specialites Chimiques, Courbevoie, FR;
Abstract
Essentially pure salicylic acid crystals, typically containing less than 0.01% inorganic salt, less than 0.01% para-hydroxybenzoic and 4-hydroxyisophthalic acid and well adopted for foodstuff and pharmaceutical applications, are facilely recovered from an aqueous solution of sodium salicylate by (i) adding an organic solvent for salicylic acid to such aqueous solution, in an amount sufficient to dissolve the salicylic acid corresponding to said sodium salt thereof, (ii) next adding thereto an at least stoichiometric amount, relative to said sodium salicylate, of a strong inorganic acid, and (iii) separating therefrom an essentially organic phase which comprises said salicylic acid and an aqueous phase which comprises an inorganic sodium salt.