碳酸钠碱熔-氟离子选择电极法检测煤中氟含量

Determination of Fluorine Content in Coal by Fluorine Ion Selective Electrode after Sodium Carbonate Alkali Fusion

煤中氟元素是煤中主要有害元素,其含量直接影响焦炭质量和焦炉状态。本文采用碳酸钠于1050℃下碱熔煤样一小时,盐酸高温消解后利用稀硫酸和稀氢氧化钠调节酸度至5.0~5.5。选择煤标准物质建立标准曲线,用氟离子选择电极法检测煤样中氟含量。该方法熔样过程简单,无需沉淀分离,采用含量相当的标准物质建立检测曲线降低了基体干扰,检测结果精度良好,相对标准偏差和相对误差均小于1.0%。

The fluorine element in coal is the main harmful element,and its content directly affects the quality of coke and the state of coke oven.In this paper,sodium carbonate was used to melt coal samples at 1050℃for one hour,after which the sample was dissolved by hydrochloric acid at high temperature.Dilute sulfuric acid and dilute sodium hydroxide were used to adjust the acidity to 5.0~5.5.We selected caol standard samples to establish the detection curve,and fluorine ion selective electrode method was used to detect fluorine content in coal samples.The method is quite simple and does not require precipitation separation.The detection curve is established with the equivalent content of reference material reduces matrix interference,and the detection accuracy is good.The relative standard deviation and relative error are less than 1.0%.