Sensitive determination of sulfur concentration in steel by spectrophotometry with a waveguide capillary cell
Abstract
Poly(tetrafluoroethylene-co-hexafluoropropylene) tubing was used as a waveguide capillary cell with an ethanol–water solvent system. The refractive index of the solvent had an effect on the light transmission through the waveguide capillary cell, but had no effect on the absorbance. The sensitivity in detecting Methylene Blue with the 2 m waveguide capillary cell was enhanced about 120-fold in comparison with that of a conventional cell (2 cm). This method can be used to determine 0.2 µg g–1 of sulfur in steel even after the conventional sample-preparation procedure.