间接电合成甲基苯甲醛产物中3种异构体的同时测定

摘要

将迭代算法、PLS与紫外吸收光谱法相结合,建立了同时测定二甲苯间接电合成甲基苯甲醛混合6组分中3种甲基苯甲醛含量的新方法.该方法将PLS镶嵌在迭代算法内部,通过多次迭代计算逐步逼近样品真值,提高了光谱的识别能力.将该方法用于4组模拟样本的测定,邻、间、对甲基苯甲醛的平均回收率分别为101％、100％和101％,预测均方差(RMSEP)分别为0.214、0.148和0.057.而应用于5批实际电合成产物中3种甲基苯甲醛同分异构体的同时测定,邻、间、对甲基苯甲醛的平均回收率分别为106％、92％和100％,相对偏差≤±19.7％,与高效液相色谱法测定结果基本吻合.%A new method, based on the composite application of the iterative algorithm, the partial least squares (PIS) and the ultraviolet spectrophotometry, was presented for the simultaneous determination of three tolualdehyde isomers among the six components prepared by indirect electrosynthesis with the xylene. The PLS was enchased to the iterative algorithm to obtain the approximation through the interactive calculations, which could improve the spectral identification ability of the products. The proposed method was applied in the simultaneous determination of three tolualdehyde isomers in four simulating samples with satisfactory results. The mean recoveries of o-tolualdehyde, m-tolualde-hyde and p-tolualdehyde were 101% , 100% and 101% , respectively, and root mean square errors of prediction (RMSEP) were 0.214, 0. 148 and 0.057, respectively. The practical application to five group electrosynthesis tolualdehyde products showed that the average recoveries were 106% , 92% and 100% for o-tolualdehyde, m-tolualdehyde and p-tolualdehyde, respectively, and the relative error was less than 19.7% . The results were compared with those obtained from the HPLC method with no significant difference.