KINETICS OF THE THERMAL-DECOMPOSITION OF NITROCELLULOSE AFTER TREATMENT WITH WEAK ACIDS

The kinetics of the thermal decomposition of nitrocellulose, treated with weak acids after nitrationin a nitric-sulfuric acid mixture, have been studied in the temperature range 75-110-degrees-C. It was found by chromatographic analysis of the gaseous decomposition products that to an extent of up to 10% the decomposition takes place according to second order autocatalysis kinetics, and the rate of decomposition can vary by a factor of approximately two with the duration of the preliminary treatment and with the nature of the original cellulose. The activation energy in the initial stages of the process, determined from the rate of evolution of N2O, CO2, CO, and NO amounted to 24 kcal/mole. It was concluded that thermal decomposition is determined by acid hydrolysis of nitrocellulose residues by sulfuric acid. The rate constant for the hydrolysis of nitrocellulose by sulfuric acid in a nitrate ester medium and the diffusion constant of H2SO4 in nitrocellulose have been estimated.