艾氏卡法测定煤中全硫的操作规范研究

依据GB/T214—2007《煤中全硫的测定方法》,结合实际工作经验,运用定量分析化学实验方法,从煤样的伴熔,水抽提,BaSO4的沉淀、过滤、洗涤、灼烧等方面详细阐述了艾氏卡法测定煤中全硫应注意的操作细节及规范操作方法、步骤。煤样伴熔时,应准确控制熔样温度与时间;水抽提时应保证清洗坩埚用水量约为50mL;BaSO4沉淀时应做到稀、热、慢、搅、陈;沉淀(或残渣)的过滤和洗涤必须不间断一次完成;过滤应按照倾泻法、转移沉淀(或残渣)至漏斗上、清洗烧杯和漏斗上的沉淀(或残渣)3步进行;BaSO4沉淀灼烧时,应将滤纸卷成三角锥形,包好沉淀后放入坩埚;将坩埚放入冷马弗炉中,在200～250℃灰化滤纸,800～850℃下灼烧20～40min。细化和规范艾氏卡法测定煤中全硫的实验步骤,不仅增强了项目的可操作性,也确保了测试结果的准确、可靠、稳定。

Operation standard of Eschka method for determination of total sulfur in coal

According to GB/T 214-2007 Determination of the total sulfur in coal and practical experiences, using quantitative analysis chemistry experiment knowledge, expound the details, standard operation method steps in the process of Eschka method for determination of total sulfur in coal from the aspects of coal sample ignition, water extraction, precipitation of barium sulfate （ BaSO4 ）, filtration, washing, ignition and the like. The ignition temperature and time should be controlled accurately when the mixture mixed with coal and Eschka is ignited. Wash the crucible thoroughly with about 50 mL hot water while transfer the ignited mixture from crucible to beaker. Precipitation of barium sulfate should be performed under the conditions of ＂dilute solution, hot solution, slow drop, stir and aging＂. Filtration and washing are continuous processes. Filtration includes three steps which is decantation filtration, transferring the insoluble matter to filter and washing the residue or precipitate. When burning BaSO4 sediment, roll the filter paper into pyramidal shape, which is used to hold sediment, put the filter paper bag into crucible, then put the crucible into the cold-vented muffle furnace. Ash the paper gradually at 200 ℃ to 250 ℃, then heat it for 20 minutes to 40 minutes at 800 ~（2 to 850 ℃. These studies provide the standard operation method and elaborate test procedure which enhance the maneuverability of the test project and ensures the accuracy, reliability and stability of the test results.