超高效液相色谱紫外法检测对苯二甲酸生产废水中的芳香羧酸

建立了超高效液相色谱－紫外法（UPLC-TUV）测定对苯二甲酸生产废水中6种芳香羧酸（邻苯二甲酸、对苯二甲酸、3-羧基苯甲醛、间苯二甲酸、苯甲酸和间甲基苯甲酸）的快速分析方法。该方法使用的色谱柱为Waters Acquity BEH C18 （2.1mm×50mm，1.7μm）,以甲醇-0.2%甲酸水（体积分数）体系进行梯度洗脱，紫外检测波长为254?nm。在优化的色谱条件下，6种芳香羧酸得到基线分离，质量浓度范围为0.5～100μg/mL（其中对苯二甲酸的质量浓度范围是0.25～50μg/mL）时，线性相关系数均大于0.9998。利用该方法检测3批废水中的6种芳香羧酸，批内相对标准偏差(RSD)均小于1.5%（n＝3）。6种芳香羧酸的一组浓度加标平均回收率均在80%～110%之间，RSD均小于6%（n＝3），表明基质干扰少，重现性好。

Determination of aromatic acids in terephthalic acid wastewater by ultra-performance liquid chromatography/ultraviolet detection

An ultra-performance liquid chromatographic (UPLC) method has been developed for the determination of the six aromatic acids (o-phthalic acid, terephthalic acid, 3-carboxybenzaldehyde, m-phthalic acid, benzoic acid and m-toluic acid) in the wastewater discharged from a plant producing terephthalic acid. Analyses were performed using a Waters Acquity BEH C18 column (2.1mm×50mm, 1.7μm). A three-component mobile phase (methanol, water, formic acid) was used for gradient elution, and ultraviolet detection was performed at 254nm. The external standard method was employed. The linear range was 0.5-100μg/mL (with terephthalic acid in the range 0.25-50μg/mL).The correlation coefficients were all more than 0.9998. The inter-day relative standard deviations (RSD) of the six aromatic acids in three groups of samples were less than 1.5% (n=3). The mean standard recoveries of the six aromatic acids were between 80% and 110%, and RSD values were less than 6% (n=3), showing that the repeatability of the UPLC method is acceptable. 