ChemicalBook > Product Catalog > Inorganic chemistry > Inorganic salts > Metal Sulphides and sulphates > Ammonium thiosulfate
Ammonium thiosulfate Chemical Properties
- Melting point:180°C (dec.)
- Density 1.679 g/mL at 25 °C(lit.)
- solubility H2O: very soluble(lit.)
- form Crystalline Powder
- color White
- OdorAmmonical odour
- Water Solubility Soluble in water, slightly soluble in acetone. Insoluble in ethanol and diethyl ether.
- Sensitive Hygroscopic
- Merck 14,562
- Stability:Stable. Hygroscopic.
- CAS DataBase Reference7783-18-8(CAS DataBase Reference)
- EPA Substance Registry SystemAmmonium thiosulfate (7783-18-8)
Ammonium thiosulfate Usage And Synthesis
- DescriptionAmmonium thiosulfate is an inorganic compound. It is white crystalline solid with ammonia odor, readily soluble in water, slightly soluble in acetone and insoluble in ethanol and diethyl ether. And Ammonium thiosulfate is used in photographic fixer. It is a so-called rapid fixer, acting more quickly than sodium thiosulfate fixers. Fixation involves these chemical reactions (illustrated for silver bromide). Ammonium thiosulfate is also used for leaching of gold and silver. It works with presence of copper as a catalyst here. This process is a nontoxic alternative gold cyanidation. Ammonium thiosulfate can be used as a fertilizer. As suggested by some research studies it can be used as an additive to coal-waste mixtures to reduce formation of very dangerous dioxins and furans.
Methods of Manufacturing
Direct reaction of ammonium sulfite with sulfur. Besides，the ATS process, sulfur dioxide is absorbed from incinerated Claus tail gas in aqueous ammonia to produce ammonium sulfate and ammonium bisulfite in solution. The solution passes to a converter where it flows countercurrent to hydrogen sulfide. Ammonium thiosulfate forms /in solution and/ is concentrated to 60 wt%.
- ToxicityAmmonium thiosulfate exists as colorless, monoclinic or white crystals with ammonia like odor. It is very soluble in cold water; slightly soluble in acetone and insoluble in alcohol and ether. It is used to clean white metal; in lubricants for metal cold working, as an analytical reagent; fungicide, reducing agent; brightener in silver plating bath, and in hair waving preparations; fog screens, and cleaning compounds for zinc base die cast metals and it is used as a desiccant and defoliant in crop bearing plants. Inhalation of dust may irritate respiratory system. Contact with eyes or skin may cause irritation. Ingestion may be harmful.
- Chemical Propertieswhite or colourless crystals
- Chemical PropertiesAmmonium thiosulfate is a white crystalline solid with an ammonia odor.
- Physical propertiesColorless, monoclinic crystal; hygroscopic; decomposes on heating above 100°C; density 1.679 g/cm3; very soluble in water (64 g/100 g at 20°C), insoluble in alcohol, and slightly soluble in acetone.
- UsesTo clean "white" metal; in photography; in lubricants for metal cold-working.
- General DescriptionAMMONIUM THIOSULFATE is a white crystalline solid. AMMONIUM THIOSULFATE is very soluble in water. The primary hazard is the threat posed to the environment. Immediate steps should be taken to limit its spread to the environment. AMMONIUM THIOSULFATE is used in photography, in chemical analysis, and for many other uses.
- Air & Water ReactionsHygroscopic. Very soluble in water.
- Reactivity ProfileAMMONIUM THIOSULFATE is sensitive to heat. AMMONIUM THIOSULFATE is incompatible with magnesium and aluminum powder. Mixtures with sodium chlorate can cause an exothermic reaction which can then decompose explosively. . Reacts with strong oxidizers such as chlorates, nitrates, and nitrites to release toxic ammonia, hydrogen sulfide, and sulfur trioxide gases. Will not polymerize. Ammonia, hydrogen sulfide, and oxides of nitrogen and oxides of sulfur may form in fires [USCG, 1999].
- Health HazardInhalation of dust may irritate respiratory system. Ingestion could be harmful. Contact with eyes or skin may cause irritation.
- Fire HazardSpecial Hazards of Combustion Products: Toxic ammonia, hydrogen sulfide, and oxides of nitrogen and sulfur may form in fires.
- Agricultural UsesAmmonium thiosulphate, [(NH4)2S2O3 or ATS] is a
crystalline salt, the aqueous solution of which is
commonly used as a liquid fertilizer. Crystalline
ammonium thiosulphate contains 19% nitrogen and 43 %
sulphur and its aqueous solution contains 12% nitrogen
and 26 % sulphur.
Ammonium thiosulphate is compatible with nitrogen and nitrogen-potassium solutions, which are neutral or slightly acidic (pH 5.8). It is also used as a suspension: As it is non-corrosive, it can be stored in steel or aluminumdrums.
Ammonium thiosulphate is prepared by the reaction of sulphur dioxide and aqueous ammonia, followed by a further reaction with elemental sulphur.
ATS can be applied directly to soils or as a foliar spray through sprinkler irrigation systems. When applied to soils, ATS decomposes into ammonium sulphate and colloidal sulphur. The ammonium sulphate is available immediately to plants, while the sulphur gets oxidized over a period of time to sulphate ion (SO42-) It is thus available to plants for a longer time. Ammonium thiosulphate also acts as a urease inhibitor. When added to a urea-ammonium nitrate solution, it inhibits urease activity for a month or so. In industry, it is also used as a photographic fixing agent, analytical reagent, fungicide and as a brightener in silverplating baths.
- Safety ProfileModerately toxic by ingestion.When heated to decomposition it emits toxic vapors ofNH4- and SOx.
- Potential ExposureUsed as an agricultural chemical and fungicide, metal lubricant; in cleaning metals; in photographic chemicals, making other chemicals. A laboratory reagent.
- ShippingUN3077 Environmentally hazardous substances, solid, n.o.s., Hazard class: 9; Labels: 9-Miscellaneous hazardous material, Technical Name Required.
- IncompatibilitiesContact with sodium chlorate may cause a violent reaction. Corrodes brass, copper, and copperbased metals.
- Waste DisposalIncinerate. It may be possible to dispose of waste material at a municipal facility if treated, neutralized and oxidized.
Ammonium thiosulfate Preparation Products And Raw materials
- Company Name:Aikon International Limited Gold
- Company Name:J & K SCIENTIFIC LTD.
- Tel:400-666-7788 010-82848833-
- Company Name:Meryer (Shanghai) Chemical Technology Co., Ltd.
- Tel:400-660-8290 21-61259100-
- Company Name:Alfa Aesar
- Company Name:Energy Chemical
- Tel:400-005-6266 021-58432009