基于氦离子化气相色谱法测定微量氧、氮的影响因素

探讨氦离子化气相色谱法测定样品中微量氧、氮含量的影响因素。采用控制变量法,对色谱柱温度、进样流量、进样管道环境及极化电压等因素对微量氧、氮测定结果的影响进行讨论和分析。结果表明,当色谱柱温度为25~45℃时,色谱柱对氧、氮吸附量最小;当进样流量不小于70 mL/min时,微量氧、氮测定结果受外界干扰最小;当极化电压为80~160 V时,氧、氮具有最佳的响应值;初次测定样品中微量氧、氮含量时,需使进样管道表面吸附的氧、氮处于饱和状态,以便获得理想的测定结果。讨论的结果可为氦离子化气相色谱法测定相关样品中微量氧、氮含量时提供技术参考。

Influence factors of determination of trace oxygen and nitrogen by helium ionization gas chromatography

The influence factors of content termination of trace oxygen and nitrogen in the sample by helium ionization gas chromatography were discussed.The factors influencing the determination results of trace oxygen and nitrogen,such as column temperature,sample flow rate,sampling pipeline environment and polarization voltage were discussed and analyzed by the control variable method.The results showed that the adsorption capacity of the column for oxygen and nitrogen was the smallest when the column temperature was 25-45℃,the determination results of trace oxygen and nitrogen were the least affected by external interference when the sample flow rate was not less than 70 mL/min,the oxygen and nitrogen had optimal response value when the polarization voltage was 80-160 V,and it is necessary to saturate the oxygen and nitrogen adsorbed on the surface of the sampling pipeline so as to obtain ideal determination results when determining the content of trace oxygen and nitrogen in the sample for the first time.This results can provide a technical reference for the determination of trace oxygen and nitrogen in related sample by helium ionization gas chromatograph.