直接电导检测-离子排斥色谱法测定碳酸氢根

发展了直接电导检测一离子排斥色谱测定碳酸氢根的方法。以Shim-pack SCR-102H离子排斥色谱柱为分离柱，选用对羟基苯甲酸为淋洗液，考察了淋洗液浓度、流速、色谱柱温度对碳酸氢根保留时间的影响。确定最佳色谱条件为：以0．1mmol／L对羟基苯甲酸为淋洗液，流速1．0mL／min，色谱柱温度40℃。在此条件下，碳酸氢根的保留时间在12min之内，检出限（S／N=3）为0．8mdL，连续5次测定峰面积的相对标准偏差为0．4％。将方法应用于可乐样品的分析，加标回收率为96．5％。

Determination of Bicarbonate by Ion-exclusion Chromatography with Direct Conductivity Detection

A method was developed for the determination of bicarbonate by ion-exclusion chromatography with direct conductivity detection. Chromatographic separation was performed on a Shim-pack SCR-102H column （300 mm ×8.0 mm i.d.） using phydroxy benzoic acid as eluent. The effects of eluent concentration, flow rate, column temperature on the retention times of bicarbonate were investigated. The optimized chromatographic conditions for determination of bicarbonate were using 0.1 mmol/L p-hydroxy benzoic acid as eluent, column temperature 40℃ and flow rate 1.0 mL/min. The retention time of bicarbonate was less 12 min under the conditions. The detection limit （SIN = 3） of bicarbonate was 0.8 mg/L. The relative standard deviation （RSD） of chromatographic peak area was 0.4 % （n = 5）. The method has been applied to the determination of bicarbonate in cola. The recovery of bicarbonate after spiking was 96.5 %.