Hydrogen sulphide spectrophotometric determination

Florin THJ. 1991. Hydrogen sulphide and total acid-volatile sulphide in feces, determined with a direct spectrophotometric method. Clin Chim Acta 196 127-134. 

The functions of the reagents used in the reduction of arsenic compounds, such as Zn, HCl, NiCla, SnCh, and KI are discussed below in connection with the Gutzeit method. Sodium borohydride also has been proposed as the reducing agent [39-42]. Sequential spectrophotometric determination of As(III) and As(V) is possible by using borohydride [40]. Hydrogen sulphide, which interferes in the reaction, is separated from arsine on cotton wool impregnated with lead acetate. 

Various forms of sulphur have been determined. Two particularly sensitive methods are discussed below. In the Methylene Blue method sulphur is first converted into hydrogen sulphide, and in the pararosaniline method SO2 is the reacting species. The classical turbidimetric (BaS04) method is also discussed. All these methods are highly selective. Spectrophotometric (and other) methods for S determination have been reviewed [13]. 

Spectrophotometric determination. Hydrogen sulphide is captured in a zinc acetate solution with an admixture of N, JV-dimethyl-p-phenylenediamine and an iron(III) salt, forming Methylene Blue. This compound is determined by spectrophotometry at 670 nm [20]. 

M. Kass, A. Ivaska, Spectrophotometric determination of sulphur dioxide and hydrogen sulphide in gas phase by sequential injection analysis technique. Anal. Chim. Acta 449 (2001) 189-197. 

We recommend spectrophotometric determination of hydrogen sulphide, but other methods will be mentioned as well (see Sections 5.3.3 and 5.3.4). 

Determination of the low levels of Mn in oceanic waters is outlined in Section 12.2.1. Here, we describe a fast and precise spectrophotometric method for dissolved Mn concentrations in the pg/L range which can be applied to samples containing several mg/L of hydrogen sulphide. 

Similar to hydrogen sulphide and sulphides, sulphur dioxide and sulphites can be determined by titration with iodine or by oxidation to sulphate followed by gravimetric determination as barium sulphate. Additionally a spectrophotometric method was developed based on the colour of p-nitroaniline which is discharged on acidification but is restored by adding formaldehyde and sulphur dioxide or sulphite. 

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See also in sourсe #XX -- [ ]

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