GB/T 223.8-2000 《Methods for chemical analysis of iron，steel and alloy--The sodium fluoride separation--EDTA titration method for the determination of aluminium content》 Related products

This standard describes a method for the determination of aluminum content in steel and alloys using sodium fluoride separation - EDTA Titrimetric method. It is suitable for samples with aluminum content in the range of 0.50% to 10.00%. The samples are first dissolved with acid. Ammonium citrate and ammonium oxalate are used to complex elements such as iron, chromium, nickel, and manganese. At pH 4~ 5, sodium fluoride separates aluminum settling from coexisting elements. Settling is dissolved by muriatic acid - Boricacid mixed acid, and fluorine is removed using nitric acid and perchloric acid. Next, excess EDTA solution is added to the slightly acidic solution, and the excess EDTA is titrated with xylenol orange as an indicator, zinc standard solution, and then the EDTA complexed with aluminum is replaced with fluoride ions, and finally the zinc standard solution is titrated. This method is suitable for samples containing up to 50 mg of zirconium, cerium or rare earth elements without interference.