EVALUATION OF METHODS FOR MONITORING AIR CONCENTRATIONS OF HYDROGEN SULFIDE

The development of different branches of industry and a growing fossil fuels minming results in a considerable emission of by-products. Major air pollutants are: CO, CO2, SO2, SO3, H2S, nitrogen oxides, as well as compounds of an organic arigin. The main aspects of this paper is to review and evaluate methods used for monitoring of hydrogen sulfide in the air. Different instrumental techniques were discussed, electrochemical, chromatographic and spectrophotometric (wet and dry), to select the method most suitable for monitoring low levels of hydrogen sulfide, close to its odor threshold. Based on the literature review the method for H2S determination in the air, involving absorption in aqueous zinc acetate and reaction with N,N-dimethylo-p-phenylodiamine and FeCl3, has been selected and preliminary verified. The adopted method allows for routine measurements of low concentration of hydrogen sulfide, close to its odor threshold in workplaces and ambient air.