Purity analysis and by-product separation of pentazole sodium

As an important intermediate in the synthesis of most energetic pentazole compounds, the reaction system of sodium pentazole is complex and has many by-products, but there is no suitable HPLC analysis method. Based on the study of ultraviolet absorption peak of sodium pentazole aqueous solution, the HPLC purity analysis method of sodium pentazole was successfully established and its sensitivity, accuracy and repeatability were verified. When the detection wavelength was 192 nm, the chromatographic column was Agilent WondaSil C18 Superb (4.6 × 250 mm, 5 μm), the mobile phase was 95% water and 5% acetonitrile mixed solution, the flow rate was 0.8 ml/min, the analysis time was 8 min, the sample size was 1 μL and the column temperature was 40 °C, a liquid phase map of sodium pentazole was obtained. The analysis results showed that the retention time of pentazole sodium was 3.76 min, and showed a good linear relationship in the range of 0.3068–0.3288 g/L. The linear equation is y = -217447.64+835837.85x, the correlation coefficient R² is 0.99997, and it has good sensitivity, accuracy and repeatability. In addition, three by-products from the synthesis of sodium pentazole were simply separated.