Kinetics Study and Process Optimization for the Reaction of Carbohydrazide with Sodium Percarbonate

Zinc tri(carbohydrazide) perchlorate(GTX) is a widely-used, safe, environmental-friendly and highly-energetic primary explosive. However, excessive quantities of carbohydrazide(CHZ) and GTX are dissolved in the mother liquor during the primary explosive manufacturing processes. To maximize the elimination of the residual CHZ, the reaction process and influence factors of the reaction of sodium percarbonate(SPC) with CHZ were studied by using the volumetric titration analysis and the controlled variable method. The optimum reaction conditions under 80 ℃ are as follows: the volume ratio of CHZ (0.1 mol•L^-1) and SPC (0.15 mol•L^-1) is 1:4, the reaction time isn't less than 90 min, and the corresponding removal rate of CHZ could be as high as 68%. Moreover, the obtained reaction time and the residual CHZ concentration were fitted by the least square method based on both first-order and second-order kinetic models. Results indicate that the aforementioned reaction accords with the second-order kinetic model.