气相色谱法分析二氨基二苯甲烷中的微量水

Analyses of Trace Water in Diaminodiphenylmethane by Gas Chromatography

利用气相色谱反吹技术,针对二氨基二苯甲烷产品的高沸点、多组分、粘度大的特点,采用热导池检测器,安装六通阀、锥形阀、电磁阀,实现气路转换、气路平衡、气路反吹功能。通过实验确定反吹时间及色谱条件,利用外标法定量分析。实验结果表明,选用GDX-102填充柱（2 m×4 mm）,进样口温度280℃,检测器温度250℃,柱箱温度100℃（1.0min）-60℃/min-50℃（2 min）,在1.0 min时开启反吹,保持4.5 min。水分含量在0.596~3.706 mg/m L之间呈良好线性关系,相关系数为0.994 6,水的检出限为9.43μg/m L,定量下限为26.22μg/m L,达到微量级别,样品加标回收率为82.82%~118.34%,精密度变异系数〈8.53%,实验验证反吹气路和分析方法的可行性。该方法简便、快捷、准确,减少大量检测时间,适用于工业分析。

Using the reverse blowing gas chromatography technology,aiming at the high boiling point, multi-component and high viscosity of the diaminodiphenylmethane, the thermal conductivity cell detector was applied. Installing the six valve and cone valve, solenoid valve to realize the function of transformation, balance and reverse blow of the gas path. The time of reverse blow and the chromatography conditions were confirmed by the experiment. Using the external standard method for the quantitative anal- ysis. The GDX-102 column （2 m × 4 mm）was used, the temperature of the injection and the detection were set at 280 ℃ and 250 ℃, respectively, the process of oven was from 100 ℃ （ 1.0 rain） to 250 ℃ （ 2 min） （ the heating rate was 60 ℃/rain）, and the time of the reverse blow was set at 1.0 min,keeping 4.5 min. The good linearity was obtained when the moisture content ranged from 0. 596 - 3. 706 mg/mL,the correlation coefficient was O. 994 6 ,the detection limit of the water was 9.43μ g/mL,the lower limit of the quantification was 26. 22 μg/mL, the recoveries ranged from 82.82% - 118.34% , and the relative standard deviations （ RS- Ds） was less than 8.53%. The experiments verified that the gas path of reverse blow and the analysis method were feasible,sim- ple ,fast and accurate ,which reduced plenty of the detection time and can be applied to industrial analysis.