桉木热水预水解液有机酸离子色谱分析

Determination of Organic Acids in Extraction Liquor from Hot-water Prehydrolysis of Eucalyptus by Ion Chromatography

关键词:  离子色谱  有机酸  桉木  热水预水解

Key Words:ion chromatography  organic acid  eucalyptus  hot-water prehydrolysis

摘要:建立了离子色谱法直接分析桉木热水预水解液中有机酸的方法，样品经简单处理后，就可采用离子色谱仪进行检测。结果表明，用IonPacTM AS11-HC阴离子分析柱（250 mm×4 mm），在2.0 mmol/L NaOH溶液等梯度淋洗15.0 min、淋洗液流速1.0 mL/min的条件下，用电导检测器可以测定桉木热水预水解液中的乙酸、甲酸和乙酰丙酸。乙酸、甲酸和乙酰丙酸的检出限分别为12.5 μg/L、6.3 μg/L、18.8 μg/L，相关系数（r2）分别为0.9999、0.9997、0.9990，相对标准偏差（RSD）分别为1.91%、0.82%、1.96%，加标回收率分别为98.02%、103.00%、96.00%；该法具有操作简单、快速、结果准确、重现性好等优点。

Abstract:A method for the determination of organic acids in extraction liquor from hot-water prehydrolysis of eucalyptus by an ion chromatography was developed. After simply treatment of the samples, the extraction liquor was analyzed using Dionex ICS-5000 ion-exchange chromatography with conductivity detector. The experimental results showed that acetic acid, formic acid and levulinic acid in the extraction liquor were separated on a IonPacTM AS11-HC anion-column (250 mm×4 mm) by using 2.0 mmol/L NaOH as mobile phase to isocratically elute at a flow rate of 1.0 mL/min in 15 minutes. Detection limits of acetic acid, formic acid and levulinic acid were 12.5 μg/L, 6.3 μg/L and 18.8 μg/L, respectively. The correlation coefficients were 0.9999, 0.9997 and 0.9990, respectively. Relative standard deviations (RSD) of repeated analyses were 1.91%, 0.82% and 1.96%, respectively. Recovery rates were 98.02%, 103.00% and 96.00%, respectively. The method developed was fast and easy to operate, with high accuracy and good repeatability.