Fourier transform infrared spectrometric determiantion of thiourea in the presence of sulphur dioxide in aqueous solution

摘要

An analytical procedure has been developed for quantitative determination of thiourea in aqueous solution acidified with sulphuric acid in the presence of sulphur dioxide. The method is based on the partial least squares treatment of data obtained by attenuated total reflectance Fourier transform infrared spectrometric method in the wave number range 1350-1450 cm(-1) and not required any sample pre-treatment. Absorbance spectra were employed for measurement using a set of 14 aqueous standard solubions of thiourea. THe method is valid in the presence of high concentration of sulphur dioxide and inorganic salts. This is particularly importnat with respect to the use of such solubitions for the leaching of gold from ores and concntrates. The method is simple, rapid, accurate (to within +_0.07%) and has been applied to the study of solutions used in leaching experiments.