离子色谱法检验液体炸药爆炸尘土中的肼离子

建立了离子色谱检测液体炸药爆炸尘土中肼离子的方法。用去离子水超声提取尘土样品中的肼离子,离心后取上清液并将其分别过OnGuardⅡ RP小柱和0.22 μm过滤膜,经IonPac CS-12A阴离子色谱柱(250 mm×4 mm)分离,采用5 mmol/L甲基磺酸等度淋洗,0.1 mol/L NaOH溶液柱后加碱,金电极安培检测器检测。结果表明,肼离子质量浓度在0.02~2.0 mg/L范围内的线性关系良好(相关系数r²=0.9997)。以信噪比(S/N)为3确定方法检出限为5.0 μg/L, S/N为10确定方法定量限为16.6 μg/L。方法回收率在95.4%~99.1%之间,相对标准偏差(RSD, n=5)在2.1%~3.3%之间。应用该方法检测液体炸药爆炸尘土中肼离子的含量为10.3 mg/kg。该方法操作简便,结果准确,适用于液体炸药爆炸尘土中肼离子的定量检测,满足刑事物证鉴定工作的需要。

Determination of hydrazine ion in explosion dust of liquid explosive by ion chromatography

A method for the determination of hydrazine ion in explosion dust of liquid explosive has been established by ion chromatography. The hydrazine ion in an explosion dust sample was extracted with deionized water by sonification and centrifugation. The large molecules and solid particles in supernatant were removed by an OnGuardⅡ RP column and a 0.22 μm filtration membrane, respectively. The filtrate was separated on an IonPac CS-12A column with isocratic elution of 5 mmol/L methanesulfonic acid (MSA). Then 0.1 mol/L NaOH solution was post-column added and the resultant solution was detected by an ampere detector with golden electrode. The results showed that, the calibration curve was linear in the range of 0.02-2.0 mg/L with a correlation coefficient (r²) of 0.9997. The limits of detection (LOD, S/N=3) and quantification (LOQ, S/N=10) of hydrazine were 5.0 μg/L and 16.6 μg/L, respectively. The recoveries ranged between 95.4% and 99.1% with the relative standard deviations (RSDs, n=5) of 2.1%-3.3%. The hydrazine content in a real explosion dust sample of liquid explosive was 10.3 mg/kg by this method. The method is simple, accurate, and suitable for the quantitative detection of hydrazine ions in explosion dust of liquid explosive, and the method can meet the needs of the criminal evidence identification work.