前言我厂过去测定萤石中氟化钙的含量,一直是采用以下两种方法。第一种方法:试样用醋酸浸取后,将沉淀连同滤纸于铂坩埚中灰化、灼烧,再以氢氟酸去掉硅,然后再用高氯酸蒸发三次,所得高氯酸皆用稀盐酸溶解,用硫化氢分离铅、钡等重金属。最后,按照一般定钙方法用草酸与草酸铵将钙离子沉淀为草酸钙,再以重量法或高锰酸钾容量法测定其中钙的含量并换算为氟化钙。第二种方法:将试样以醋酸浸取后,所得沉淀用氯化钙溶液溶解,用硫化氢分离重金属。然后如上法将钙离子沉淀为草酸 Preface Our factory in the past determination of fluorite in fluorite content, has been the use of the following two methods. The first method: the sample is leached with acetic acid, the precipitate with the filter paper in a platinum crucible ashing, burning, and then remove the silicon hydrofluoride, and then evaporated three times with perchloric acid, the resulting perchlorate are all used Dissolved dilute hydrochloric acid, hydrogen sulfide separation of lead, barium and other heavy metals. Finally, calcium oxalate is precipitated with oxalic acid and ammonium oxalate as calcium oxalate according to the method of determining calcium, and the content of calcium therein is determined by gravimetric method or potassium permanganate volumetric method and converted into calcium fluoride. The second method: After the sample is leached with acetic acid, the resulting precipitate is dissolved with calcium chloride solution and the heavy metal is separated with hydrogen sulfide. Then, the above method precipitates calcium ions as oxalic acid