Study on the reaction of hexamine and acetic acid system by online infrared spectrum technology

In the process of HMX commercial production, acetic acid is recycled, which may contain impurities such as HNO₃ and H₂O, so the reaction of acetic acid with hexamine may influence the stability of HMX production process. The online infrared spectrum technology was used to study the reaction of the hexamine and acetic acid system. The results show that, after the hexamine is added in the acetic acid, new N-H bond absorption peaks appear at the range of 2700~2300 cm^-1, -CO₂^- absorption peak appears at 1557 cm^-1, the hexamine C-N absorption peaks at 671 cm^-1 and 809 cm^-1 are shifted, the acetic acid O-H bond absorption peak at 3026 cm^-1 is shifted. The hexamine reacts with acetic acid to form the salt. The structures of hexamine, acetic acid and the hexamine acetate were optimized by use of Gaussian package. The results show that the hexamine acetate is stable. Gaussian simulation results are consistent with the experimental results.