离子色谱法测定复混肥料中氯离子含量

IC Determination of Chloride Ion in Compound Fertilizers

按国标GB15063-2001所述处理样品。取10mL滤液稀释50倍,使Cl^-浓度保持在约20mg·L^(-1)。注入高交换容量Dionex Ionpac AS 23阴离子色谱柱,用0.8mmol·L^(-1)碳酸氢钠和4.5mmol·L^(-1)碳酸钠混合溶液作等度淋洗,流量为1.0mL·min^(-1),用抑制电导检测,保留时间定性,外标法峰面积定量,在5.0～50.0mg·L^(-1)范围内氯离子浓度与色谱峰面积呈线性关系,加标回收率在87.2%～104.9%之间。分析结果的平均值与国标法测定值相符。

Sample of compound fertilizer was treated as described in GB 15063-2001,and 10 mL aliquot of the filtrate were diluted 50 times to keep the mass concentration of Cl^- at ca.20 mg·L^（-1）.The Dionex Ionpac AS 23 column was used as stationary phase and the mixture of 0.8 mmol·L^（-1） NaHCO_3 solution and 4.5 mmol·L^（-1） Na_2CO_3 solution was used as the mobile phase in the elution at the flow-rate of 1.0 mL·min^（-1）.Suppression conductivity detection was used in measurements.Retention time was used for identification,and external standard method was used in determination.Linear relationship between values of peak area and mass concentration of Cl^- ion was kept in the range of 5.0 to 50.0 mg·L^（-1）.Recovery was tested by standard addition method,giving values of recovery in the range of 87.2%to 104.9%.Samples of compound fertilizer were analyzed by the present method and checked by the method of National standard,results obtained were found in good consistency.