The thermal decomposition of sodium ethyl xanthate (SEX) adsorbed
onto activated carbon was studied by coupled thermogravimetric
analysis-Fourier transform infrared spectroscopy (TG-FTIR). Two
discrete mass losses were observed, in the temperature ranges 100 - 230C and 200 - 340C. The same two gases, carbonyl sulphide (COS)
and carbon disulphide (CS2), were the main gases evolved in each of the
mass losses. Samples of activated carbon from two industrial plants were obtained
and analysed by TG-FTIR. COS and CS2 were not detected in one of the
samples. The other sample did show evidence of COS and CS2, which
indicated that fouling of the carbon by SEX was still present. Other
organic compounds were detected in the evolved gas stream of both
samples, indicating the presence of organic reagents other than SEX.