Chemical process
OwnerGert Jansen, Per Wolffinventors
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Abstract
An improved process for the production of sodium salicylate and salicylic acid from phenol at a high degree of conversion with a concomitant reduction in undesirable by-products. The process comprises reacting a sodium phenolate with carbon dioxide in a direct, single step at a temperature above about 165.degree. C. to produce directly sodium salicylate, which is then converted by conventional means to the salicylic acid.
Claims6
A process for preparing sodium salicylate which comprises reacting phenol with an aqueous solution of sodium hydroxide in a reaction zone to form sodium phenolate;
- heating the resulting reaction product mixture at elevated temperatures, which are raised to above about 175.degree. C., to remove water therefrom;
- introducing carbon dioxide into the reaction zone while the thus produced sodium phenolate is maintained at an elevated temperature above about 175.degree. C., and producing sodium salicylate directly in a single step by reaction between the sodium phenolate and carbon dioxide at said elevated temperatures.
In a process for the production of salicylic acid comprising sequentially reacting phenol with an aqueous solution of sodium hydroxide in a reaction zone to form sodium phenolate, contacting carbon dioxide with said sodium phenolate to form sodium salicylate, and then acidifying said sodium salicylate to form salicylic acid;
- the improvement which comprises contacting the carbon dioxide with the sodium phenolate at a reaction temperature of above about 175.degree. C. to reduce substantially the formation of by-product sodium salts of non-salicylic acids.
Dependencies are inferred from the claim text.