Hydrogen peroxide first oxidizes the cyanide to cyanate, and then the cyanate is hydrolyzed to carbonate. The reaction formula is:

CN ^- +H ₂ O ₂ ^- CNO ^- +H ₂ O

CNO ^- +2H ₂ O - NH ₄ ⁺ +CO ₃ ^{2 -}