滴定法测定刻蚀酸中氢氟酸、氟硅酸和硝酸含量  

Titrimetric Determination of Hydrofluoric Acid,Fluosilicic Acid and Nitric Acid in Etching Acid

作　　者：唐晓婵[1,2] 张晓霞 王达彤 张小蒙 岳涛 Tang Xiaochan;Zhang Xiaoxia;Wang Datong;Zhang Xiaomeng;Yue Tao(Qingdao University of Science&Technology,Shandong Chemical Industry Research Institute,Jinan,Shandong 250014,China;Organic Reaction in Aqueous Engineering Research Center of Shandong Province,Jinan,Shandong 250014,China)

机构地区：[1]青岛科技大学山东化工研究院,山东济南250014 [2]山东省水相有机合成及高效清洁分离工程技术研究中心,山东济南250014

出　　处：《化学世界》2022年第6期393-398,共6页Chemical World

基　　金：山东省“泰山学者”建设工程基金(No.08190201)资助项目。

摘　　要：建立了一种测定氢氟酸-氟硅酸-硝酸刻蚀体系中三种酸含量的滴定方法。利用硝酸钾与氟硅酸生成氟硅酸钾沉淀,消除氟硅酸的干扰,用氢氧化钠标准溶液和硝酸镧标准溶液分别测定溶液的总酸度和氢氟酸含量。将氟硅酸在强碱性条件下水解生成氟化物,用硝酸镧标准溶液测定溶液中的总氟,扣除氢氟酸含量得到氟硅酸的含量,以总酸度减去氢氟酸和氟硅酸含量计算硝酸的含量。考察了反应pH值和反应时间对氟硅酸含量测定的影响,测定结果与模拟样品理论值一致,相对标准偏差(RSD)<1.0%,按照该法前处理步骤制备的溶液可稳定24 h,有利于批量操作。A titration method was developed for the determination of hydrofluoric acid, fluosilicic acid and nitric acid in etching solution. Potassium nitrate was adapted to eliminate the interference of fluosilicic acid on hydrofluoric acid. The total acidity and hydrofluoric acid content of the solution were determined by sodium hydroxide and lanthanum nitrate standard solution, respectively. Fluosilicic acid was hydrolyzed into fluoride by strong alkaline, and the total fluoride in the solution was determined by lanthanum nitrate standard solution. The content of fluosilicic acid was obtained by deducting the content of hydrofluoric acid from the total fluoride content. The content of nitric acid was calculated by subtracting hydrofluoric acid and fluosilicic acid from total acidity. The factors such as reaction time and acidity to affect the content of fluosilicic acid were studied. The results were consistent with the theoretical values of simulated samples, and the repeatability relative standard deviation(RSD) is less than 1.0%. The solution prepared according to the pretreatment steps of this method can be stable for at least 24 h, which is beneficial to batch operation.

关 键 词：氢氟酸 氟硅酸 硝酸 刻蚀酸 

分 类 号：O657.3[理学—分析化学]