Microwave digestion and inductively coupled plasma atomic emission spectrometric method for the determination of niobium, tungsten, zirconium, cobalt,vanadium and tin in low-medium alloy steel
WEI Li,ZHOU Su-lian,HE Xiao-hu
1.Guangxi Metallurgical Products Quality Supervision and Test Station, Nanning 530023, China;
2 College of Chemistry and Bioengineering,Guilin University of Technology, Guilin 541004, China
Abstract:Niobium, tungsten, zirconium, cobalt and vanadium in low-medium alloy steel could improve the performance of the steel, for example, enhancing the strength, corrosion resistance and weldability. However, tin was a kind of harmful element in the steel. Therefore, it was necessary to determine these elements in steel. The microwave digestion was used for the dissolution of sample in this study. Because of the increase of temperature and pressure of dissolved sample, the sample was dissolved in sulfuric acid and hydrofluoric acid medium quick and completely. Then, oxalic acid and boric acid were added to complex niobium and excessive hydrofluoric acid, respectively. The same amount of iron and acid as in testing solution were added into calibration curve series solutions to make the matrix and acidity in calibration curve series solutions and testing solution consistent. So the interference of matrix effect could be eliminated. Then, the simultaneous determination of niobium, tungsten, zirconium, cobalt, vanadium and tin in testing solution by inductively coupled plasma atomic emission spectrometry (ICP-AES) was carried out. The proposed method was applied to the determination of niobium, tungsten, zirconium, cobalt and vanadium in low-medium alloy steel standard sample, and the determination values were in good agreement with the certified values. The relative standard deviations (RSD) were 0.03%-1.2%.