气相色谱法分析聚甲醛二甲基醚合成产物中的甲醛含量  

Analysis of Formaldehyde in Synthesized PODE_m Products by Gas Chromatography

作　　者：许竞早[1] 张育红[1] 王川[1] 高晓晨[1] 

机构地区：[1]中国石化上海石油化工研究院,上海201208

出　　处：《石油化工》2015年第9期1127-1130,共4页Petrochemical Technology

摘　　要：采用CP—Wax毛细管柱（25m×0．25mm i．d．×0．2μm），建立测定聚甲醛二甲基醚（PODEm）合成产物中甲醛含量的气相色谱法；针对该体系中难分离的甲醇和甲醛组分，优化了色谱条件，考察了方法的精密度和准确性，用该方法分析了PODEm实际试样。实验结果表明，使用CP—Wax毛细管色谱柱，实现了甲醛、甲缩醛、甲醇和水的完全分离；该方法测定PODEm合成产物中甲醛含量时，PODEm合成产物中的甲醛含量与峰面积呈良好的线性关系，线性相关系数为0．9982～0．9995，实际试样加标回收率为98％～101％，相对标准偏差小于3．0％（n=5），最低检测限为0．049％（w）。与传统的化学滴定法相比，气相色谱法无需前处理，操作简便，测定结果准确、可靠。该方法可用于PODEm合成产物中甲醛含量的定量分析，也可用于含甲醇的体系中常量甲醛的分析。A novel gas chromatography method for the analysis of formaldehyde in synthesized polyoxymethylene dimethyl ethers（PODEm） products was established with a CP-Wax capillary column（25 m × 0.25 mm i.d. ×0.2 μm） and TCD detector. For methanol and formaldehyde separated difficultly in the system, the chromatographic conditions were optimized. The repeatability and accuracy of the method were investigated. The experimental results showed that four components in the system, namely formaldehyde, methylal, methanol and water, were separated completely by using the CP-Wax capillary column. The linear correlation coefficients of the standard curves were 0.998 2-0.999 5. The addition standard recoveries of the method were in the range of 98%-101%. The relative standard deviations and the detection limit were less than 3.0%（n=5） and 0.049%（w）, respectively. Compared with the traditional chemical titration method, the gas chromatography method without pre-treatment is simple and convenient, and the results are more accurate. It can also be used for the analysis of formaldehyde in methanol system.

关 键 词：聚甲醛二甲基醚 气相色谱法 甲醛 甲缩醛 甲醇 

分 类 号：O657.7[理学—分析化学]