NITROGENOUS PRODUCTS OBTAINED BY OZONIZATION OF AZO DYES

Nitrogenous substances produced by the ozonization of azo dyes [1]~[5] in aqueous solution were investigated. Nitrogen gas was found to be the main product. The yields of nitrogen gas, differing from one another due to the variety of dyes, were 65~92% based on the total nitrogen of azo group and pyrazole ring. Only minor amount of nitrate was produced. In the case of [2], in addition to nitrate, a small amount of ammonium ion was produced. The qualitative analyses of nitrogenous residue after the ozonization by means of spot tests showed the absence of nitrosamine, C-nitroso, nitro, and amine compounds. © 1979, The Chemical Society of Japan. All rights reserved.