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  2. Sulfidation - Wikipedia

    en.wikipedia.org/wiki/Sulfidation

    The increased resistance to corrosion found in stainless steel is attributed to a layer of chromium oxide that forms due to oxidation of the chromium found in the alloy. [4] The process of liquid sulfidation has also been used in the manufacturing of diamond-like carbon films. These films are generally used to coat surfaces to reduce the wear ...

  3. Sulfur cycle - Wikipedia

    en.wikipedia.org/wiki/Sulfur_cycle

    Sulfur can be found under several oxidation states in nature, mainly −2, −1, 0, +2 (apparent), +2.5 (apparent), +4, and +6. When two sulfur atoms are present in the same polyatomic oxyanion in an asymmetrical situation, i.e, each bound to different groups as in thiosulfate, the oxidation state calculated from the known oxidation state of accompanying atoms (H = +1, and O = −2) can be an ...

  4. Shell–Paques process - Wikipedia

    en.wikipedia.org/wiki/Shell–Paques_process

    The process consist of three main sections: An absorber (gas washing section), a bioreactor (sulfide oxidation and regeneration of washing liquid) and Sulfur handling section as shown in the figure below: The washing step uses a dilute alkaline solution to remove hydrogen sulfide (H 2 S) from the sour gas according to: H 2 S + NaOH → NaHS + H 2 O

  5. Claus process - Wikipedia

    en.wikipedia.org/wiki/Claus_process

    A schematic process flow diagram of a basic 2+1 ... This is a strongly exothermic free-flame total oxidation of hydrogen sulfide generating sulfur dioxide that reacts ...

  6. Sulfide - Wikipedia

    en.wikipedia.org/wiki/Sulfide

    The sulfide ion does not exist in aqueous alkaline solutions of Na 2 S. [3] [4] Instead sulfide converts to hydrosulfide: S 2− + H 2 O → SH − + OH −. Upon treatment with an acid, sulfide salts convert to hydrogen sulfide: S 2− + H + → SH − SH − + H + → H 2 S. Oxidation of sulfide is a complicated process.

  7. Sulfur metabolism - Wikipedia

    en.wikipedia.org/wiki/Sulfur_metabolism

    These processes typically produce hydrogen sulfide as a byproduct, which can go on to serve as an electron donor in sulfur oxidation. [11] Sulfate reduction by sulfate-reducing bacteria is dissimilatory; the purpose of reducing the sulfate is to produce energy, and the sulfide is excreted.

  8. Supergene (geology) - Wikipedia

    en.wikipedia.org/wiki/Supergene_(geology)

    Supergene processes include the predominance of meteoric water circulation (i.e. water derived from precipitation) with concomitant oxidation and chemical weathering. The descending meteoric waters oxidize the primary (hypogene) sulfide ore minerals and redistribute the metallic ore elements.

  9. Microbial oxidation of sulfur - Wikipedia

    en.wikipedia.org/wiki/Microbial_oxidation_of_sulfur

    The oxidation of reduced sulfur compounds is performed exclusively by Bacteria and Archaea.All the Archaea involved in this process are aerobic and belong to the Order Sulfolobales, [19] [20] characterized by acidophiles (extremophiles that require low pHs to grow) and thermophiles (extremophiles that require high temperatures to grow).