Abstract:The content of sulfate radical in organic amines is determined by Inductively Coupled Plasma-Atomic Emission Spectrometry（ICP-AES）. The experimental conditions such as the amount of hydrochloric acid, the degree of evaporation and the correction value of residual sulfur are investigated. The low valence sulfur in the sample solution is evaporated by hydrochloric acid. The sulfur that cannot be evaporated exists in the form of sulfate radical, which can be determined directly on the spectrometer. The result of this method is accurate, simple and rapid. The detection limit is 0.45mg/L, the recovery is 98.5% ~ 100.2%，and the determination range is 10 ~ 100g / L.