Quantitative measurement model for sulfate in the temperature range of 298.15–343.15 K based on vacuum ultraviolet absorption spectroscopy

In order for SO 3 measurement without impurity gas interference in coal-fired power plants, a quantitative measurement model for sulfate in the temperature range of 298.15–343.15 K based on vacuum ultraviolet absorption spectroscopy was created. A vacuum ultraviolet absorption spectrum measurement system that eliminates oxygen interference was set up, and the vacuum ultraviolet absorption of sulfate was ascertained at 1 atm pressure by means of vacuum combined with nitrogen purging. The law of the vacuum ultraviolet absorption of sulfate with temperature was revealed, that the full width at half maximum ( FWHM ) and peak absorbance ( A max ) both increased linearly with temperature. The quadratic function relationship between the integrated area ( OP ) of the vacuum ultraviolet absorption spectrum of sulfate and temperature was found, and a universal sulfate concentration measurement model was established in the temperature range of 298.15–343.15 K. The average relative calculation error of this model for 0.0025 mol L −1 sulfate was as low as 0.6%, which supports the measurement of trace sulfate.