气相色谱法测定DMO重组分及其杂质含量

Determination of DMO Heavy Component and Its Impurities by Gas Chromatography

建立一种测定DMO(草酸二甲酯)重组分及其杂质含量的方法。该重组分是煤制乙二醇技术的副产物,在不同有机溶剂中具有较低的沸点和熔点,且在56℃以下会凝固结晶。使用了ShimCap-InoWax毛细管色谱柱和FID氢火焰离子化检测器,并在优化后的色谱条件下成功分离了DMO重组分及其杂质,获得了良好的检测效果。结果表明:在所选的色谱条件下,DMO重组分的质量分数与测量结果呈线性关系,测量范围为0~99.916%。此外,DMC和甲醇这两种常见杂质也呈现出良好的线性关系,其测量范围分别为0~0.20%和0~0.65%。在加标回收率实验中,DMO的加标回收率在99.00%~101.23%,变异系数为0.57%。而对于DMC和甲醇这两种杂质,加标回收率分别在97.83%~106.01%和97.85%~102.64%,变异系数分别为1.05%和0.82%。本方法在测定DMO重组分及其杂质含量方面取得了良好的结果。

A method for determining the composition and impurity levels of DMO(dimethyl oxalate)was developed.DMO is a byproduct of coal-to-ethylene glycol technology and has low boiling and melting points in different organic solvents.It crystallizes below 56℃.A ShimCap-InoWax capillary column and FID hydrogen flame ionization detector were used,and the DMO heavy component and its impurities were successfully separated under the optimized chromatographic conditions,and good detection results were obtained.The results showed that,under the selected chromatographic conditions,there was a linear correlation between the mass fraction of DMO and the measurement results within the range of 0 to 99.916%.For the two common impurities,DMC(dimethyl carbonate)and methanol,good linear relationships were also observed with measurement ranges of 0 to 0.20%and 0 to 0.65%,respectively.In the spiked recovery experiments,the recovery rates of DMO ranged from 99.00%to 101.23%,with a coefficient of variation of 0.57%.For DMC and methanol,the recovery rates ranged from 97.83%to 106.01%and 97.85%to 102.64%,respectively,with coefficients of variation of 1.05%and 0.82%.This method has achieved satisfactory results in determining the composition and impurity levels of DMO.