硅钙合金中硅的快速分析法  

Rapid Determination Method of Silicon Element in Calcium-Silicon Alloy

作　　者：任亦然 REN Yi-ran(Sichuan Province Academy of Industiral Environmental Monitoring,Chengdu 610046,China)

机构地区：[1]四川省工业环境监测研究院,四川成都610046

出　　处：《化工管理》2023年第15期44-46,66,共4页Chemical Engineering Management

摘　　要：传统手工法用高氯酸脱水重量法对硅钙合金中硅元素的含量进行测定:通过两次灼烧后重量的差值,计算出二氧化硅的质量,进一步得到硅的含量。然而,该方法不仅步骤较为复杂,对操作人员要求较高,同时也需要较长的检测周期,不利于日常检测的时效性要求。对比其他铁合金样品中硅元素含量的测定,对硅钙合金中的硅元素含量可以使用容量法进行检测:对已符合要求的硅钙合金粉末,用硝酸和氢氟酸溶解,加入饱和硝酸钾溶液生成氟硅酸钾沉淀。过滤后,取滤纸和沉淀,先用氢氧化钠溶液中和剩余的硝酸和氢氟酸,再用沸水使氟硅酸钾水解,析出氢氟酸。再次用氢氧化钠溶液滴定,计算得出硅的质量分数。按此方法对两组硅钙合金标样中硅的成分进行了测定,检测结果与标准值相符,其相对标准偏差分别为0.177%和0.268%。该方法简便、迅速,数据结果准确性高,重复性好,符合日常检测工作的需要。Traditionally,the determination of silicon element in calcium-silicon alloy was often realized by gravimetric method:after ignition to constant weight twice,weighing twice respectively and gaining the weight of silicon dioxide,hence,the content of silicon element.However,this method not only takes complicated steps so that it requires more from the operating personnel,but also costs much time thus don’t fit for daily experiments.Compared with other measurements to determine the content of silicon element,it appears that the content of silicon in calcium-silicon alloy can be achieved by volumetric method,that is:appropriate powder sample of calcium-silicon alloy was first dissolved completely in the solution of nitric acid and hydrofluoric acid.The solution was then added saturated nitrate solution to produce potassium fluosilicate precipitate.It was followed by filtration.After the filtration,sodium hydroxide solution was used to neutralize the acid residue in the filter paper as well as that in the precipitate.Then,we added boiled water to hydrolyze potassium fluosilicate and produce hydrofluoric acid.Sodium hydroxide solution was added again in titration and therefore gained the content of silicon.Two sets of samples were determined in this method.The results were consistent with their standard values.The relative standard deviations was 0.177%and 0.268%respectively.This method was more convenient and faster.The results were accurate and repeatable,that is,it’s appropriate to daily determination.

关 键 词：硅钙合金 硅 氟硅酸钾 滴定 

分 类 号：TQ54[化学工程—煤化学工程]