• 中文核心期刊
  • 中国科技核心期刊
  • CSCD来源期刊
  • DOAJ 收录
  • Scopus 收录

微波消解-电感耦合等离子体发射光谱法测定粉煤灰中的镓

Determination of Gallium in Coal Fly Ash by Inductively Coupled Plasma-Optical Emission Spectrometry with Microwave Digestion

  • 摘要: 粉煤灰中镓元素含量为12~230μg/g,测定粉煤灰中的镓对实现粉煤灰高附加值利用具有重要的意义。传统敞口酸溶法作为样品的预处理方法存在局限性,如需使用大量氢氟酸,对分析仪器腐蚀大,溶样时间长,在开放容器中易造成元素损失和环境污染。微波消解法具有消解完全、元素损失量少、消解时间短等优点,可以有效解决酸溶法的不足。本文选取内蒙古某电厂采集的粉煤灰,采用硝酸-氢氟酸-盐酸-高氯酸微波消解法对粉煤灰样品进行预处理,电感耦合等离子体发射光谱法(ICP-OES)测定元素含量。结果表明:使用硝酸-氢氟酸-盐酸-高氯酸(5:1:5:1),消解温度190℃,消解时间30min,微波功率1400W时,镓被浸出完全。方法检出限为0.004mg/L,相对标准偏差(RSD)为1.7%,加标回收率为95.1%~100.9%。本方法在体系中引入盐酸,减少了氢氟酸的用量,显著缩短了除氟时间,降低了对分析仪器的损害,且操作方便,可应用于粉煤灰中微量元素镓的测定。

     

    Abstract:
    BACKGROUNDThe content of gallium in coal fly ash is 12-230μg/g. The determination of gallium in coal fly ash is crucial to realize the high-value-added utilization of coal fly ash. As a sample pretreatment method, the conventional open wet digestion method has limitations including a large amount of hydrofluoric acid, corrosion of analytical instruments, long dissolution time, the loss of elements, and environmental pollution. Microwave digestion has the advantages of complete digestion, minimal loss, and short digestion time, which can effectively solve the shortcomings of the open wet digestion method.
    OBJECTIVESTo develop a good method for the determination of gallium in coal fly ash.
    METHODSThe coal fly ash was collected from a power plant in Inner Mongolia. The sample was digested with nitric acid (5.0mL), hydrofluoric acid (1.0mL), hydrochloric acid (5.0mL) and perchloric acid (1.0mL) by microwave digestion and then determined by inductively coupled plasma-optical emission spectrometry (ICP-OES).
    RESULTSThe results showed that gallium could be leached totally using HNO3-HF-HCl-HClO4 (5:1:5:1, V/V) when the temperature was 190℃, the time 30 minutes and the microwave power 1400W. The limit of detection was 0.004mg/L. The relative standard deviation (RSD) was 1.7% with the recoveries ranging from 95.1% to 100.9%.
    CONCLUSIONSICP-OES with microwave digestion method adds hydrochloric acid and reduces the amount of hydrofluoric acid, thus shortening the time of removing fluoride and reducing the damage to instruments. The method is easy to be used for the determination of trace gallium in coal fly ash.

     

/

返回文章
返回