摘要
建立了碱熔-离子选择电极法测定煤样中氟的分析方法。煤样低温灰化后和氢氧化钾混合,在600℃马弗炉中熔融,然后用热水提取,加柠檬酸三钠掩蔽铝、钙、镁,调节酸度,以酚红为指示剂,氟离子选择性电极,用标准加入法测定样品溶液中氟离子浓度。氟离子的线性相关系数为0.9995,氟的检出限为0.022μg/m L,方法用煤样标准样品中氟的测定,结果与认定值相吻合,相对标准偏差为2.37%。方法对照试验表明本方法测定值与国标法GB/T 4633-1997测得的氟含量一致。此法简单、准确、迅速,适合批量煤样中氟的快速分析。
A method was developed for the determination of fluorine in coal using alkali melt tbr sample preparation and ion selective electrode method. After calcination in nickel crucibles at 450 ℃, the samples were fused with kalium hydroxide at 600℃. The melt was leached with hot water. The interferences from AI^3＋, Ca^2＋, Mg^2＋ etc were eliminated using trisodium citrate dihydrate. With the p H of solution adjusted and using phenol red as indicator, the fluorine content was determined by ion selective electrode and standard addition method. The correlation coefficient of the calibration curve lbr fluoride was 0.9995 with a detection limit of 0.022 μg/mL. This method was applied in the determination of fluorine in coal certified reference material. The method was consistent with the certified value, and the relative standard deviation （RSDs, n=6） was 2.37 %. Control trials showed that the measured values by this method were consistent with those obtained by national standard method GB/T 6730.28-2006. This method is not only simple, rapid, accurate but also can be used for the determination of fluorine content in coal.
出处
《广东化工》
CAS
2017年第14期115-116,共2页
Guangdong Chemical Industry
关键词
离子选择电极
碱熔
煤样
氟化物
ion selective electrode： alkali melt： coal： fluorine
