The spectrophotometric determination of sulphur in iron alloysMethylene blue method

Voltammetric Determination of Low‐Molecular‐Weight Sulfur Compounds in Hydrothermal Vent Fluids – Studies with Hydrogen Sulfide, Methanethiol, Ethanethiol and Propanethiol

“…No reference material for hydrothermal vent fluids exists; thus, the proposed method was validated against the reference Methylene Blue spectrophotometric method [22]. Because the speciation of sulfides cannot be performed by the reference method, the regression analysis was carried out considering the total sulfide content of the samples.…”

“…Before use, equal volumes of each hydrothermal vent fluid sample were mixed to compose a pooled sample to be used as a representative matrix of the real samples to test the methodology through recovery experiments. The total sulfide content of the samples (without speciation) was also determined spectrophotometrically by the Methylene Blue method adapted from Kriege and Wolfe [22].…”

“…The voltammetric method was tested in real samples spiked with the analytes in order to test the methodology as a tool to assay and speciate sulfides by on-ship measurements. Real samples, free of sulfides according to the spectrophotometric Methylene Blue method [22], were used as a matrix. Hydrothermal vent fluid samples were pooled and separated into 6 identical subsamples, to which the analytes were spiked in concentrations ranging from 0.5 to 4.0 mmol L À1 for the recovery experiments (Table 1).…”

Ferrous Metallurgy

“…Comparison of chemical methods (solution of the steel in acid with or without further treatment to complete decomposition of the sample and separation of the nitrogen as ammonia by distillation) with the hot (vacuum fusion or carrier gas) methods have been made (49, 97,188,165). Since there are many embodiments of each method, the general conclusion that one is better than the other does not seem warranted.…”

“…In the rapid colorimetric determination of sulfur, the sulfur dioxide obtained by the combustion method was reacted with fuchsine and the color was measured at 530 µ (249). In other methods the sulfur was converted to hydrogen sulfide and determined colorimetrically by the iodine-azide reaction (222) or with V,V-dimethyl-p-phenylendiamine in the presence of ferric iron as methylene blue (188).…”