Hydrogen sulphide abundance

Hydrogen sulphide is present in many mineral springs, and even free sulphur is occasionally found therein.2 Many metallic sulphides, for example, iron pyrites, galena, zinc blende, stibnitc and cinnabar, occur abundantly. Sulphur dioxide, sulphites, sulphuric acid and sulphates are also found in nature, more especially in waters springing from volcanic earth, whilst the sulphates of certain metals such as calcium, barium and magnesium exist in large deposits. 

Sulphur colouring matters are more or less soluble in water, but readily soluble in alkalies or alkaline sulphides when treated with hydrochloric acid or, better, with hydrochloric add and stannous chloride, they emit hydrogen sulphide when burnt they give an odour of sulphur dioxide and leave a more or less abundant residue containing alkaline sulphates and sulphites. 

Any precipitated sulphides being removed by filtration, the filtrate is boiled to expel hydrogen sulphide, then oxidised with a few drops of concentrated nitric acid and boiled with ammonium chloride and ammonia. The liquid is then filtered and the precipitate carefully washed with hot water and dissolved in dilute nitric acid, the nitric acid solution being treated with excess of sodium hydroxide, boiled for a few minutes and filtered when cold. Any ferric and chromium hydroxides remain on the filter, the filtrate containing the alumina as sodium aluminate. If the filtrate is heated to boiling with ammonium chloride, an abundant precipitation of gelatinous white flocks will occur in the case of a sample dyed on an aluminium mordant. 

Metastable ion decomposition of hydrogen sulphide to give sulphur ions and molecular hydrogen has been investigated [247]. The metastable peak abundances were in the ratios 16 2 1 for H2S HDS D2S. 

PtLABON has shown that liquid sulphur absorbs hydrogen sulphide in abundance this circumstance complicates somewhat the verification of the preceding laws, as may be seen in F abon s memoir, I e. 

Along with natural gas, oil fields have other products. Hydrogen sulphide is the most abundant of the impurities. A small quantity in natural gas is desirable as a warning of leakage. When large quantities are present this sour gas is used to manufacture carbon black or is processed for sulphur recovery. Sometimes helium is present in useful quantities. Carbon dioxide is found in some fields. It is recovered and used in the manufacture of dry ice. 

Hydrogen sulphide is produced by obligate anaerobic bacteria if there are abundant sulphate and organic substrates at redox potentials below zero. 

Hydrogen can be produced more abundantly by allowing sulphuric acid to act upon one of the metals, preferably zinc. As mentioned in a previous part of this book, sulphuric acid, upon coming in contact with zinc, results in the production of zinc sulphide and hydrogen, according to the following formula ... 

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