METHOD FOR DETERMINATION OF ANTIMONY AND ARSENIC IN STEEL AND CAST IRON

摘要

FIELD: chemistry.;SUBSTANCE: concentrated hydrofluoric, hydrochloric and nitric acids in ratio 16:10:5, respectively, are added successively to the test sample. Decomposition of the sample by acid mixture is carried out during heating. To remove nickel, iron and chromium compounds from the solution, alkali metal (sodium or potassium) hydroxide solution is added to the obtained solution until pH value 6-7 is reached, and then alkali metal acetate solution is added to reach pH value 5-6. The obtained precipitate is separated by filtration. Arsenic content in the filtered solution is measured by the method of inductively coupled plasma atomic emission spectrometry at wavelength of 193.696 nm and antimony content is assessed at wavelength of 206.836 nm.;EFFECT: increased accuracy of determination.;3 cl, 1 dwg, 1 tbl, 1 ex