色谱组合法分析对二甲苯氧化产物

建立了气相色谱和高效液相色谱相结合的方法分析对二甲苯氧化产物,其中气相色谱分析对二甲苯(PX)、对甲基苯甲醇(TALC)和对甲基苯甲醛(TALD),高效液相色谱分析对甲基苯甲酸(p-TA)、对羧基苯甲醇(4-HMBA)、对羧基苯甲醛(4-CBA)和对苯二甲酸(TA),得到了气相色谱和高效液相色谱的分析条件。实验结果表明,各组分标准工作曲线的线性关系较好,其中PX,TALC,TALD的线性相关系数分别为1.000,0.999,0.998,相对标准偏差小于1.4%;p-TA,4-HMBA,4-CBA,TA的线性相关性系数均为1.000,相对标准偏差小于1.5%;准确度实验结果表明,所有组分的回收率介于99.23%~101.29%之间。此方法可用于对二甲苯液相氧化产物的分析和测量粗TA中杂质的含量。

Analysis of Products from p-Xylene Oxidation by Combined Chromatographies

Products from p-xylene(PX)oxidation were analyzed by combination of gas chromatography and high performance liquid chromatography.The gas chromatography was used to analyze PX,p-tolualcohol(TALC)and p-tolualdehyde(TALD),and high performance liquid chromatography was used to analyze p-toluic acid(p-TA),4-hydroxymethylbenzal acid(4-HMBA), 4-carboxybenzaldehyde (4-CBA),and terephthalic acid(TA).Relative coefficients for standard curves of PX,TALC,and TALD are 1.000,0.999 and 0.998,respectively.Relative coefficients for standard curves of p-TA,4-HMBA,4-CBA and PTA are all 1.000.Precision experiments showed that relative standard deviation(RSD)of analysis for PX,TALC and TALD are less than 1.400 0%,and RSD of p-TA, 4-HMBA,4-CBA and PTA are less than 1.500 0%. The recoveries of all components are between 99.23% and 101.29%.The combined analysis method can be used to analyze PX oxidation products and impurity in crude terephthalic acid.