Taking the combustion tear gas mixture as the research object, the system formula was optimized by adding a different mass fraction of 5-amino-1H-tetrazole(5AT). TG-DSC, a thermocouple, and a laser smoke test system were used to characterize the characteristic combustion parameters such as combustion temperature and velocity, as well as the end-point effects such as smoke concentration and particle size. Starink’s method, the Flynn–Wall–Ozawa method, and the Coats–Redfern method were used to evaluate the pyrolysis kinetic parameters of the samples. The results show that when the mass fraction of 5-amino-1H-tetrazole in the system is 10%, the maximum combustion temperature of the sample decreases by nearly 70 °C and the smoke concentration increases by 12.81%. The kinetic study also found that with a different mass fraction of 5-amino-1H-tetrazole in the system, the main reaction model of the mixed agent in the first, third, and fourth stages of pyrolysis changed significantly, but for the second stage of sample pyrolysis, the main reaction model (the A4 model) showed a high degree of consistency, which can be considered as the thermal diffusion stage of the tear agent capsicum oleoresin (OC) (the temperature range is 220~350 °C), which is highly consistent with the results of the TG-DSC analysis. It was also confirmed that OC’s thermal diffusion is mainly concentrated in this stage. The results of this study show that adding an appropriate amount of the combustible agent 5-amino-1H-tetrazole to the combustion tear gas mixture can improve its combustion performance and smoking performance, which provides an important, new idea for the development of a new generation of safe, efficient, and environmentally friendly tear gas mixtures.

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The riot dyeing agent Rhodamine B is a dyeing agent loaded in riot ammunition, which can produce serious environmental pollution after use. In order to eliminate the environmental pollution of rhodamine B, a decontamination method with simple operation, wide material sources and green environment protection was studied. First, an orthogonal experiment was used to obtain a concentration ratio of decontaminant with excellent performance, that is, the best decontamination effect of rhodamine B when the concentration of hydrogen peroxide was 15%, the concentration of boric acid was 3.5% and the concentration of ferrous sulfate heptahydrate was 0.4%. Then, the actual decontamination effect of the formulated decontaminants on rhodamine B was examined by test tube decontamination method and immersion decontamination method. The results of the decontamination experiments showed that the decontaminants formulated according to the optimal results of the orthogonal experiments had significant decontamination effects on both the rhodamine B powder and the non-woven masks contaminated with rhodamine B. This decontamination method has good application value and can be used for the decontamination of riot dyeing ammunition contaminated sites and clothes to eliminate the environmental hazards of dyeing agent rhodamine B.