色谱

色谱

• 研究论文 • 上一篇    下一篇

离子色谱法测定烟气脱硫海水中的亚硫酸根离子

尹丽倩, 袁东星*, 郭娟, 刘锡尧   

  1. Environmental Science Research Center, Xiamen University, Xiamen 361005, China
  • 收稿日期:2009-06-01 修回日期:2009-08-01 出版日期:2009-11-30 发布日期:1981-12-25
  • 通讯作者: 袁东星

Determination of sulfite in flue gas desulfurization with seawater by ion chromatography

YIN Liqian, YUAN Dongxing*, GUO Juan, LIU Xiyao   

  1. Environmental Science Research Center, Xiamen University, Xiamen 361005, China
  • Received:2009-06-01 Revised:2009-08-01 Online:2009-11-30 Published:1981-12-25
  • Contact: YUAN Dongxing

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818

被引次数

22

摘要： 建立了燃煤电厂烟气脱硫海水中亚硫酸根(SO2~3)的离子色谱-脉冲安培检测方法。色谱柱为IonPac AS14A阴离子交换柱,流动相为14 mmol/L NaOH-12 mmol/L Na2CO3溶液(pH 11.7),流速1.2 mL/min,脉冲安培法检测。因SO2~3易被氧化,故在采样时加入甲醛作为保护剂,使之稳定存在。在测定海水样品前,用NaOH溶液(pH 12.0)沉淀海水中的Mg2+,以避免其在pH较高的流动相中生成沉淀堵塞色谱柱。采用该方法检测SO2~3的线性范围为0～100 mg/L,平均回收率为116.8%,检出限为0.05 mg/L;对7.5,25.0和75.0 mg/L的海水基底加标溶液分别进行9次平行测定,其相对标准偏差(RSD)分别为2.1%,3.1%和4.0%。该方法具有快速、灵敏、选择性好等特点,用于烟气脱硫的海水中SO2~3的检测,可得到令人满意的结果。

关键词: 海水 , 离子色谱法, 亚硫酸根离子, 烟气脱硫

Abstract: The technology for flue gas desulfurization (FGD) with seawater is widely adopted by coal-fired power plants in coastal areas. SO2 in the flue gas is absorbed by alkaline seawater and transfered in aqueous phase as sulfite (SO2~3), and most SO2~3 is transformed to sulfate (SO2~4) after an aeration process. The remaining SO2~3 in the seawater discharged to sea area may be harmful to marine organism because of its biological toxicity, thus it is necessary to determine the concentration of SO2~3 in the seawater for desulfurization. In this study, the method of determination of SO2~3 in the seawater by ion chromatography was investigated. The separation was achieved on an IonPac AS14A column with 14 mmol/L NaOH-12 mmol/L Na2CO3 solution as the mobile phase at a flow rate of 1.2 mL/min, and the detection was performed by a pulsed amperometric detector. Formaldehyde was added as a protective agent when sampling because the SO2~3 is easy to be oxidized. To avoid the formation of Mg(OH)2 in the mobile phase with high pH value which might block the column, the Mg2+ in seawater was precipitated by NaOH solution (pH 12.0) before sample determination. The method showed good linearity within the range of 0~100 mg/L with an average recovery of 116.8%. The method detection limit (MDL) reached as low as 0.05 mg/L. The relative standard deviations (RSD) for seawater matrix samples spiked at levels of 7.5, 25.0 and 75.0 mg/L were 2.1%, 3.1% and 4.0% (n=9), respectively. The method has been applied for the determination of SO2~3 in flue gas desulfurization seawater with the advantages of being fast, sensitive and selective.

Key words: flue gas desulfurization, seawater , sulfite, ion chromatography (IC)