滴定法测定CL-20的酸值

Determination of Acid Value of CL-20 by Titration Method

为建立CL-20酸值的可行测定方法,通过电位滴定法和指示剂滴定法对比,筛选出合适的溶剂和指示剂,得到酸值测定的最佳体系。结果表明,最佳电位滴定体系是以氢氧化钠/水溶液为滴定剂、250mL微酸性丙酮和50mL水的混合液为溶剂。最佳指示剂滴定体系是上述滴定剂、溶剂和中性红-亚甲基蓝为指示剂。上述两种方法的标准偏差小于0.000 303 11%,最小达0.000 01%,相对标准偏差小于0.999 49%,最小达0.194 58%。以氢氧化钾/乙醇替代上述滴定剂中的氢氧化钠/水,同样满足使用要求。

To establish feasible method to determine the acid value of hexanitrohexaazaisowurtane（CL-20）, through comparing potentiometric titration method with indicator titration method and screening out the best solvent and in- dicator, the best system to determine the acid value was obtained. The results show that the optimum potentiometric titration system is sodium hydroxide / water solution as titrant and mixed solution of 250mL slightly acidic acetone and 50mL water as solvent. The optimum indicator titration system is the above titrant and solvent, and the neutral red--methylene blue as the indicator. The standard deviation of above two methods is less than 0. 00030311% and the minimum is 0. 00001%. The relative standard deviation of above two methods is less than 0. 99949%, and the minimum is 0. 19458%. The substitution of potassium hydroxide / ethanol for the sodium hydroxide / water in the above titrant can also meet the operating requirement.