Abstract
Volatile sulphur compounds (VOSCs) and hydrogen sulphide are key contributors to odour emissions and represent a significant challenge for accurate odour monitoring due to their low odour thresholds and the potential analytical interferences. This study evaluates the performance of HORIBA APSA-370 designed for the detection of sulphur species thanks to two conversion units for specific detection and quantification of H2S and Total Reduced Sulphur (TRS). From the obtained results, the instrument demonstrated good selectivity and reliability for SO2 measurements in the simpler configuration (detector UV for SO2), with no significant interference observed from tested sulphur-containing and aromatic compounds. In contrast, the internal H2S conversion unit showed limited selectivity, with substantial signal interference from other sulphur species even if present at low concentrations, limiting its applicability for specific H2S quantification. The TRS conversion unit, however, provided robust and accurate oxidation of sulphur compounds across a concentration range of 5–1000 ppb, yielding consistent results for both simple and complex sample matrices. These findings highlight the limitations associated with selective H2S monitoring in the presence of mixed VOSCs, while showing promising perspectives for broader sulphur compound analysis in odour-related applications.
