Simultaneous Analysis of Organic Acids and Inorganic Anions in Alcoholic Drink(Dongjiu) by Ion Chromatography
离子色谱法同时分析董酒中的有机酸与无机阴离子

An ion chromatographic method for the simultaneous analysis of organic acids and inorganic anions in Dongjiu (alcoholic drink) was developed. An anion exchange column Shim-pack IC-A1(100 mm x 4.6 mm) was used. In non-suppressed anion exchange chromatography, potassium hydrogen phthalate (KHPh) is used as eluent most widely. However, there are several problems in this eluent for the analysis of Dongjiu (alcoholic drink) sample, such as the influence of a negative peak to the determination of acetic acid, ascorbic acid and lactic acid, the non-resolution of ascorbic acid, and lactic acid, and part overlapping of the peak of acetic acid with water peak. In order to solve these problems, a mixed eluent of 0.50 mmol/L KHPh and 0.25 mmol/L phthalic acid(H2Ph) was used in this work. The main organic acids and inorganic anions in Dongjiu were separated without interference peaks. The detection limits obtained by using the mixed eluent were 0.05-0.13 mg/L, several times lower than those obtained by using single KHPh eluent. This method, being without pretreatment, is simple to operate.