摘要
采用焦磷酸分离岩石及粉尘中的游离二氧化硅 ,再用氢氟酸—饱和氯化钾将分离出来的游离二氧化硅溶解 ,使硅形成K2 SiF6沉淀 .然后水解 ,应用氟离子选择性电极间接测定游离二氧化硅的含量 ,方法简便、准确、快速 .
This investigation is to analyse the free SiO 2 in rocks and dust by a fluoride-ion selective electrode(F-I.S.E)method.In this method,the free silicon can be separated with pyrophosphoric acid(H 4P 2O 7)firstly,and dissolved with hydrofluorde acid(HF),and then saturated with potassum chlorade(KCl).The precipitate of K 2SiF 6 can be formed.Therefore,the free SiO 2 can be determined indirectly by the F-I.S.E after the hydrolosis of the precipitate.The results obtained by this method indicate that the free SiO 2 in the rock or dust can be determined accurately,as compared with the weight method.
