HPLC法测定乙醛酸水溶液中的草酸

摘要

采用HPLC测定乙醛酸水溶液中的草酸,以C18为色谱柱,0.025 mol/L磷酸二氢钾-0.01 mol/L四丁基氢氧化铵溶液(磷酸调pH =2.0)为流动相,流速1.0 mL/min检测波长为210 nm.结果表明,草酸在0.4064～3.251 2 mmol/L的摩尔浓度范围内线性良好,R2=0.999 7.加标回收率为98.3％～100.4％,RSD为1.06％,检出乙醛酸水溶液中草酸平均含量为3.22％,RSD为1.08％.该方法简单,具有良好的重复性与可靠性.%The determination of oxalic acid in the solution of glyoxylic acid by HPLC. Under the condition of 0.025 mol/L potassium dihydrogen phosphate-0.01 mol/L tetrabutylammonium hydroxide (phosphorous acid to pH =2.0) as mobile phase at 210 nm. The calibration curves showed good linearities in the range of 0.406 4 ~ 3.251 2 mmol/L with correlation coefficients of 0.999 7. The average recoveries were 98.3% ~ 100. 4% with RSD of 1. 06%. The average content of oxalic acid in the solution of glyoxylic acid were 3. 22% , with RSD of 1.08%. The method could be applied to the determination of oxalic acid in the solution of glyoxylic acid with good reproducibility and reliability.