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

An analytical procedure has been developed for quantitative determination o f thiourea in aqueous solution acidified with sulphuric acid in the presenc e of sulphur dioxide. The method is based on the partial least squares trea tment of data obtained by attenuated total reflectance Fourier transform in frared spectrometric method in the wave number range 1350-1450 cm(-1) and n ot required any sample pre-treatment. Absorbance spectra were employed for measurement using a set of 14 aqueous standard solutions of thiourea, The method is valid in the presence of high concentration of sulphur dioxid e and inorganic salts. This is particularly important with respect to the u se of such solutions for the leaching of gold from ores and concentrates. T he method is simple, rapid, accurate (to within 10.07%) and has been applie d to the study of solutions used in leaching experiments. (C) 2001 Elsevier Science B.V. All rights reserved.