Comparison between Ion-chromatography and Titration Methods for the Determination of Sulfite in Wastewater Containing Furfural

Sulfur-containing species, such as sulfite, are detrimental to the operation of anaerobic systems, therefore, it is critical to determine their concentrations in order to optimize an anaerobic reactor. In this study, the traditional titration method for the determination of sulfite was applied to acid-condensate samples from an acid sulfite pulp mill effluent, and the results showed that they were consistently lower than those from ion chromatography (IC). It was found that the presence of furfural in the acid-condensate samples can interfere with the titration for sulfite, resulting in lower sulfite values; the higher the furfural concentration in the sample, the lower the indicated sulfite concentration by titration. It was concluded that IC method is a reliable method for determining the sulfite concentration for samples containing furfural.