Determination of sulphur content in waste materials by ion chromatography

The aim of this work is to apply an ion - chromatography method which was initially developed for the determination of sulfur content in fuels, on other classes of samples as municipal waste and oil and sewage sludge. With respect to their physical properties and texture, solid waste materials as municipal waste, are typically strongly heterogeneous and thus, sample preparation can be critical in obtaining reliable analysis results so that, particle size reduction and homogenizing of the municipal waste was an important step in conducting the experiments. The homogenization of the samples was performed by cutting and then
grinding the material in two steps: first a reduction of the particles to diameters passing a 10-mm sieve and secondly to diameters passing a 2-mm sieve. The sulfur extraction from the homogenized waste samples was carried out by the combustion method in the calorimetric bomb. Sulfur as sulfate anion was then analyzed by ion-chromatography and gravimetric techniques and the results were compared. Depending on the nature and sulfur content of the sample, the repeatability standard deviation sr and the relative repeatability standard deviation RSD of the results were of the same order of magnitude for the both gravimetric and ion –
chromatography methods and they were in the range of about 0.01 - 0.05 % for sr and in the range of about 3.23 – 6.25 % for RSD.