针对目前磷酸-乙酸混酸体系中乙酸含量分析方法准确度低、操作繁琐的问题，提出了一种以丙酸为内标物采用气相色谱快速测定磷酸-乙酸混酸体系中乙酸含量的方法。通过加标回收实验、精密度实验、与文献方法对比测试实验、磷酸浓度干扰实验来验证本方法的准确性与适用性。结果表明，乙酸的空白加标回收率为97.67%~104.55%，样品的加标回收率为97.72%~104.35%，多次测定结果的相对标准偏差为1.26%；与文献方法对比发现，本方法的准确度较高；当磷酸浓度在0~70%（质量分数）时，乙酸的分析结果基本不受磷酸含量的影响。由此说明，该色谱分析方法可准确、快速、简便地测定磷酸-乙酸混酸体系中乙酸的含量，对相关行业乙酸含量的分析具有重要意义。

A method using gas chromatography with propionic acid as an internal standard was proposed to solve the problems of low accuracy and cumbersome operation in the analysis of acetic acid content in the phosphoric acid and acetic acid mixed system.The accuracy and applicability of this method were verified through recovery experiments，precision experiments，comparison tests with literature methods，and experiments on the interference of phosphoric acid concentration.The experimental results showed that the recoveries of blank standard of acetic acid was 97.67%~104.55%，and the recoveries of sample standard of acetic acid was 97.72%~104.35%，and the precision of multiple test results was 1.26%.Compared with the literature methods，this method had high accuracy.In addition，for phosphoric acid concentrations at the range of 0~70%，the analytical results of acetic acid were not affected by the phosphoric acid content.Therefore，this chromatographic analysis method could accurately，rapidly，and easily determine the content of acetic acid in the phosphoric acid and acetic acid mixed system.This method was of great importance for the analysis of acetic acid content in related industries.