气相色谱法测定盐酸羟胺肟化反应液中环己酮、环己酮肟和硝基环己烷的含量

Determination of Cyclohexanone,Cyclohexanone Oxime and Nitrocyclohexane in Hydroxylamine Hydrochloride Oximation Reaction Solution by GC

建立了气相色谱法(GC)同时测定盐酸羟胺肟化反应液中环己酮、环己酮肟和硝基环己烷含量的方法。称取盐酸羟胺肟化反应液0.1 g,加入5.0 mL环戊酮肟内标溶液,用无水乙醇稀释至100 mL。优化的GC条件为:以Kromat KB-624色谱柱(30 m×0.32 mm,1.8μm)为分析柱,采用程序升温方式分离待测物和其他杂质组分,流量2.0 mL·min^(-1),分流比为100∶1。以环戊酮肟为内标物,内标法定量。结果表明:环己酮、环戊酮肟、环己酮肟、硝基环己烷色谱峰与相邻组分的分离度均大于2.0,3种待测物的标准曲线的线性范围均为1.0~1000.0 mg·L^(-1),检出限(3S/N)均为0.02 mg·L^(-1);按标准加入法进行回收试验,3种待测物的回收率为97.5%~102%,测定值的相对标准偏差(n=6)为1.5%~4.5%。方法用于测定8批盐酸羟胺肟化反应液,测得环己酮、环己酮肟和硝基环己烷的质量分数为5.51%~55.32%,11.86%~88.52%和0.10%~80.62%。

A method for simultaneous determination of cyclohexanone,cyclohexanone oxime and nitrocyclohexane in hydroxylamine hydrochloride oximation reaction solution by gas chromatography(GC)was developed.Hydroxylamine hydrochlonde oximation reaction solution of 0.1 g was added to 5.0 mL internal standard solution of cyclopentanone oxime,and diluted to 100 mL by anhydrous ethanol.The optimized conditions of GC were found.Kromat KB-624 chromatographic column(30 m×0.32 mm,1.8μm)was used to separate the targets and other impurities by temperature programmed method,with the flow rate of 2.0 mL·min^(-1) and the split ratio of 100∶1.Internal standard method was applied to quantification with cyclopentanone oxime as internal standard substance.As shown by the results,the resolutions of the chromatographic peaks of cyclohexanone,cyclopentanone oxime,cyclohexanone oxime and nitrocyclohexane with their adjacent components were all greater than 2.0.Linear ranges of the standard curves of 3 compounds were 1.0-1000.0 mg·L^(-1),with detection limits(3 S/N)of 0.02 mg·L^(-1).Recovery test was made by standard addition method,giving results of 3 compounds in the range of 97.5%-102%,with RSDs(n=6)of the determined values ranged from 1.5%to 4.5%.This method was used to determine 8 batches of hydroxylamine hydrochloride oximation reaction solution,and the mass fractions of cyclohexanone,cyclohexanone oxime and nitrocyclohexane were 5.51%-55.32%,11.86%-88.52%and 0.10%-80.62%,respectively.