Studies on simultaneous determination of RE elements in steels with dibromo-p-methye-methylsulfonazo by double-wavelength spectrophotometry

The method for the determination of light rare earth elements based on the color reaction of RE(Ⅲ) with DBM-MSA in 0.24～0.72 mol/L HCl by double-wavelength(spectrophotometry) was(proposed.) The(maximum)(absorption)(wavelength) are all 640 nm.Beer′s law is(obeyed) in the (concentration) range of 0～500 μg/L for RE(elements.) Their apparent molar absorptivity are between 0.8×10~5 and 1.5×10~5 L·mol·cm~(-1).In(double-)(wavelength)(condition,) the(apparent) molar(absorptivity) is 1.5～2.6×10~5 L·mol~(-1)·cm~(-1) and its(sensitivity)(increases) 75%(compared) with that of the(single)(wavelength.) The(method) (was)(applied) to the(determination) of(light) rare earth(elements) in steels with satisfactory results.