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Thiosulfate ion extensively forms diverse complexes with transition metals. This reactivity is related to its role in of silver-based photography. Also reflecting its affinity for metals, thiosulfate ion rapidly corrodes metals in acidic conditions. Steel and stainless steel are particularly sensitive to pitting corrosion induced by thiosulfate ...
The advantages of this approach are that (i) thiosulfate is far less toxic than cyanide and (ii) that ore types that are refractory to gold cyanidation (e.g. carbonaceous or Carlin-type ores) can be leached by thiosulfate. One problem with this alternative process is the high consumption of thiosulfate, which is more expensive than cyanide.
Tetrathionate is a product of the oxidation of thiosulfate, S 2 O 2− 3, by iodine, I 2: 2 S 2 O 2− 3 + I 2 → S 4 O 2− 6 + 2I −. The use of bromine instead of iodine is dubious as excess bromine will oxidize the thiosulfate to sulfate.
These salts are often generated by oxidation of thiosulfate. For example, tetrathionate is obtained by oxidation of thiosulfate ion with iodine (reaction is used in iodometry): S 2 O 2− 3 + I 2 → S 4 O 2− 6 + 2 I −. More specialized routes involve reactions of sulfur chlorides with bisulfite salts: SCl 2 + 2 HSO − 3 → [O 3 SSSO 3] 2 ...
The decomposition of dithionite produces reduced species of sulfur that can be very aggressive for the corrosion of steel and stainless steel. Thiosulfate (S 2 O 2− 3) is known to induce pitting corrosion, whereas sulfide (S 2−, HS −) is responsible for stress corrosion cracking (SCC).
Pitting corrosion, or pitting, is a form of extremely localized corrosion that leads to the random creation of small holes in metal. The driving power for pitting corrosion is the depassivation of a small area, which becomes anodic (oxidation reaction) while an unknown but potentially vast area becomes cathodic (reduction reaction), leading to ...
As an oxygen scavenger agent, it is used to treat water being fed to steam boilers to avoid corrosion problems, [6] in the photographic industry, it protects developer solutions from oxidation and (as hypo clear solution) to wash fixer (sodium thiosulfate) from film and photo-paper emulsions.
The branched thiosulfate oxidation pathway, a mechanism in which water-insoluble globules of intermediate sulfur are formed during the oxidation of thiosulfate and sulfide. It is present in all the anoxygenic photolithotrophic green and purple sulfur bacteria, and the free-living as well as symbiotic strains of certain sulfur-chemolithotrophic ...