Cyanuric chloride high yield - from cyanogenchloride dried over phosphorus pentoxide before trimerisation prolonging catalyst li

Cyanuric chloride is prepd. in 83-95% yields from cyanogen chloride by drying it over P2O5 prior to trimerisation with activated charcoal in presence of 5% Cl2 or COCl2 above 250 degrees C. The life-time of the catalyst is thereby prolonged to 6-9 months. In an example a 95.4% conversion to cyanuric chloride is achieved by passing CNCl, dried over P2O5, and Cl2 over 5g activated charcoal at 360 degrees at specified speeds and a contact-time of 15 secs.