GB865294A - Improvements in the production of cyanuric acid and alkali metal cyanurates - Google Patents

Abstract

In a process for the production of cyanuric acid by heating urea in a water immiscible organic liquid which does not dissolve or attack the urea or cyanuric acid, after the urea has been reacted, the reaction mixture contained in the reaction vessel is treated with a solution of potassium or sodium hydroxide, acetate, carbonate, or formate in water or a water/alcohol mixture and the resulting cyanurate solution is separated from the water immiscible organic liquid. The use of aqueous solutions of sodium or potassium hydroxide containing less than 25% wt. of the sodium or potassium hydroxide is preferred. The reaction mixture is preferably treated with an amount of solution sufficient to cause the cyanuric acid to be substantially converted into the corresponding trialkali metal cyanurate. The resulting solution of cyanurate after isolation from the water immiscible organic liquid which may subsequently be returned to the reaction vessel, may be reacted with chlorine to yield tri or dichloro cyanuric acid or be acidified with mineral acids to recover the cyanuric acid. Alcohols specified for use in the water/alcohol mixtures are methanol, ethanol, or isopropanol, the alcohol being present in amount sufficient only to ensure complete solution of the sodium or potassium compounds therein.