GB/T 18114.11-2010 《Chemical analysis methods of rare earth concentrates - Part 11：Determination of fluorine contentv - EDTA titration》 Related products

This standard specifies a method for determining the amount of fluorine in rare earth concentrates using the EDTA Titrimetric method. It is suitable for rare earth concentrates with fluorine content ranging from 2.00% to 20.00%. During the determination, the sample is distilled with perchloric acid in 135 ° C 140 ° C water vapor to separate fluorine from Miscellaneous elements. At a pH value of 2.02.5, a lanthanum chloride standard solution is added to form lanthanum fluoride settling with fluoride. Subsequently, in a hexamine buffer solution at pH 5.5~ 6.0, using xylenol orange as an indicator, excess lanthanum chloride is titrated using the EDTA standard solution, thereby calculating the mass fraction of fluorine. The standard details the required reagents and preparation methods.