Name | Ammonium thiosulfate |
Synonyms | AMMONIUM HYPOSULFITE AMMONIUM THIOSULFATE Ammonium thiosulfate Ammonium thiosulphate Aminonium Thiosulfate AMMONIUM THIOSULPHATE AMMONIUM THIOSULFATE PURE Ammoniumthiosulfatewhitextl AmmoniumThiosulfateH8N2O3S2 Thiosulfuricacid,diammoniumsalt thiosulfuricacid[h2s2o3],diammoniumsalt AMMONIUM THIOSULFATE CRYSTALLIZED STAB |
CAS | 7783-18-8 |
EINECS | 231-982-0 |
InChI | InChI=1/2H3N.H2O3S2/c;;1-5(2,3)4/h2*1H3;(H2,1,2,3,4) |
Molecular Formula | H8N2O3S2 |
Molar Mass | 148.21 |
Density | 1.679 g/mL at 25 °C (lit.) |
Melting Point | 150 °C (lit.) |
Water Solubility | Soluble in water, slightly soluble in acetone. Insoluble in ethanol and diethyl ether. |
Solubility | H2O: very soluble(lit.) |
Appearance | Crystalline Powder |
Color | White |
Odor | Ammonical odour |
Merck | 14,562 |
Storage Condition | 2-8 ℃, stored in nitrogen |
Stability | Stable. Hygroscopic. |
Sensitive | Hygroscopic |
MDL | MFCD00015965 |
Physical and Chemical Properties | Character white monoclinic crystal. relative density 1.679 solubility: very soluble in water. Insoluble in alcohol. Slightly soluble in acetone. |
Use | Used as photographic fixer, metal cleaning agent, plating solution and reducing agent |
Risk Codes | R33 - Danger of cumulative effects R36/37/38 - Irritating to eyes, respiratory system and skin. |
Safety Description | S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S37 - Wear suitable gloves. |
WGK Germany | 1 |
RTECS | XN6465000 |
TSCA | Yes |
HS Code | 28323000 |
Toxicity | LD50 orl-rat: 2890 mg/kg GTPZAB 26(6),54,82 |
colorless monoclinic crystals. Deliquescence. Soluble in water, acetone-soluble, insoluble in alcohol, ether. The aqueous solution was long-lived with sulfur precipitation. 150 C decomposition of the formation of ammonium sulfite, sulfur, ammonia, hydrogen sulfide and water.
ammonium sulfite is formed by the interaction of ammonium bicarbonate with sulfur dioxide and water, and then reacts with sulfur, and ammonium thiosulfate is obtained by filtration, evaporation, cooling crystallization and separation. Alternatively, ammonium pentasulfide and excess aqueous ammonia are added to an aqueous solution of ammonium sulfate, and after the reaction, the sulfur is removed by filtration and then evaporated under vacuum at a low temperature to obtain ammonium thiosulfate.
for photographic fixation, the silver halide emulsion film is more soluble than the sodium salt, and has the advantage that the washing time is short and the silver recovery is easy. Also used for silver plating plating solution, metal cleaning agent, reducing agent, aluminum magnesium alloy casting protective agent and chemical reagent.
packed in a plastic woven bag lined with a polyethylene plastic bag. 25kg net weight per bag. Should be stored in a cool, dry warehouse. To prevent moisture. Should be stored in a closed device filled with ammonia.
EPA chemical substance information | information provided by: ofmpeb.epa.gov (external link) |
Use | ammonium thiocyanate, also known as ammonium thiocyanate, is commonly used as a photographic fixative, a metal cleaner, a plating solution, and a reducing agent. In agriculture The intermediate for synthesis of the insecticide Buprofezin, tert-butyl isothiocyanate, and the intermediate for the insecticide zoxaparb, the fungicide leaf kupazole, the herbicide fluthiachlor, etc., thiosemicarbazide, it is also used in the manufacture of hydrogen peroxide auxiliary raw materials and dyes, organic synthesis of Polymerization Catalysts, etc.; In the photosensitive industry; Used as a photographic fixative, sodium salt more easily soluble silver halide emulsion film, it has the advantages of short washing time and easy recovery of silver; It is also used as the main component of silver plating bath, as a complexing agent in cyanide-free electroplating, thiosulfate and silver ions are combined to form thiosulfate silver complex ions. Improve the cathodic polarization, so that the silver layer crystallization fine, good coverage. General dosage of 200~250g/L. Also used in the synthesis of organic boron compounds, plasticizers, welding flux; Metal surface detergent; Aluminum magnesium alloy casting protection agent. It is used as a fungicide and an analytical reagent in medicine. used as a photographic fixative, metal cleaning agent, electroplating solution and reducing agent ammonium thiocyanate, also known as ammonium thiocyanate, an intermediate for the synthesis of Buprofezin, tert-butyl isothiocyanate, and the insecticide zoxaparb, thiosemicarbazide, an intermediate of the herbicide fluorothiachlor and the like, is also used as an auxiliary raw material and dye for producing hydrogen peroxide, a polymerization catalyst for organic synthesis, and the like. The photosensitive industry is used as a photographic fixative, and has an advantage that the washing time is short and the recovery of silver is easy because the emulsion film of silver halide is more soluble than the sodium salt. It is also used as the main component of silver plating bath; Detergent for metal surface; Aluminum magnesium alloy casting protective agent. In medicine used as fungicides, Analytical reagents. This product is used as a complexing agent in cyanide-free electroplating, and thiosulfate is combined with silver ions to form silver complex ions of thiosulfate. Improve the cathodic polarization, so that the silver layer crystallization fine, good coverage. General dosage of 200~250g/L. used as analytical reagent, photographic fixer and reducing agent This product is used for semiconductor components, synthesis of organic boron compounds, plasticizers, welding flux photosensitive industry used as photographic fixer, the emulsion film of silver halide, which is more soluble than sodium salt, has the advantages of short washing time and easy recovery of silver, and is also used as the main component of silver plating bath, detergent for metal surface, aluminum magnesium gold casting protective agent. In medicine used as fungicides, Analytical reagents. |
production method | 1. Ammonium sulfite method: NH3 water is added into the reaction kettle, and SO2 is passed to obtain ammonium sulfite for standby. In addition, the ammonium polysulfide was added into the reaction kettle, and after adding water to dissolve, the above solution was slowly added with stirring, and the reaction was carried out at 30~55 °c, so that the reaction solution remained dark orange during the reaction. The amount of ammonium sulfite solution was slightly lower than the theoretical amount. After the addition of the ammonium sulfite solution was complete, steam was passed for several hours to drive off the ammonium sulfide. The reaction solution was filtered, distilled under a nitrogen atmosphere, and decolorized with activated carbon to remove sulfur. Frozen crystallization, centrifugal dehydration, drying under the protection of ammonia to obtain the finished product. ammonium bicarbonate method: ammonium sulfite is formed by the interaction of ammonium bicarbonate with sulfur dioxide and water, which is filtered to remove impurities and then reacted with sulfur by heating and boiling, then filtered, evaporated, cooled and crystallized, the final product of ammonium thiosulfate was prepared by centrifugal separation. 2NH4HCO3 SO2 H2O →(NH4)2SO3 2H2O 2CO2 ↑;(NH4)2SO3 S →(NH4)2S2O 3. Carbon disulfide method: carbon disulfide and a slight excess of liquid ammonia are mixed with water, and the reaction is carried out for about 20H at a pressure of 5.88 × 105Pa and a temperature of 100 ° C. The reaction solution is evaporated under reduced pressure to remove hydrogen sulfide, at a liquid temperature of 105 ° C., iron and heavy metals were removed with ammonium sulfide, filtered, and the filtrate was concentrated under reduced pressure, cooled and crystallized in a crystallizer, centrifuged and dried to obtain ammonium thiocyanate. Reaction equation: CS2 3NH3 = NH4SCN NH4HS NH4HS = nh3Δh2s ↑ 4. Sulfur method: Stir appropriate amount of water and sulfur powder in the reactor to form slurry, and slowly add solid sodium cyanide in several times, the reaction is carried out at about 110 ℃ to generate sodium thiocyanate, and then solid ammonium chloride is added to generate ammonium thiocyanate. Then barium thiocyanate is added to the reaction solution to remove impurity and clarify, and the supernatant is evaporated under reduced pressure, the sodium chloride is concentrated and precipitated, and then filtered, cooled, crystallized, separated and dried to obtain ammonium thiocyanate. Reaction equation: NaCN S = NaSCN NaSCN NH4Cl = NaCl NH4SCN NH3 water is added into the reaction vessel, and SO2 is passed to obtain ammonium sulfite for standby. In addition, the ammonium polysulfide was added into the reaction kettle, and after adding water to dissolve, the above solution was slowly added with stirring, and the reaction was carried out at 30~55 °c, so that the reaction solution remained dark orange during the reaction. The amount of ammonium sulfite solution was slightly lower than the theoretical amount. After the addition of the ammonium sulfite solution was complete, steam was passed for several hours to drive off the ammonium sulfide. The reaction solution was filtered, distilled under a nitrogen atmosphere, and decolorized with activated carbon to remove sulfur. Frozen crystallization, centrifugal dehydration, drying under the protection of ammonia to obtain the finished product. ammonium bicarbonate method generates ammonium sulfite by the interaction of ammonium bicarbonate with sulfur dioxide and water, which is filtered to remove impurities and then heated and boiled with sulfur to react, then filtered, evaporated, cooled and crystallized, and centrifuged, A finished product of ammonium thiosulfate was obtained. Its 2NH4HCO3 SO2 H2O →(NH4)2SO3 2H2O 2CO2+(NH4)2SO3 S →(NH4)2S2O ammonium thiocyanate can be prepared by carbon disulfide method or sulfur method. Carbon disulfide method carbon disulfide and a slight excess of liquid ammonia mixed with water, under the condition of pressure 5.88 × 105Pa, temperature 100 ℃ reaction for about 20h, the reaction solution is evaporated under reduced pressure to remove hydrogen sulfide, at a liquid temperature of 105 ° C., iron and heavy metals were removed with ammonium sulfide, filtered, and the filtrate was concentrated under reduced pressure, cooled and crystallized in a crystallizer, centrifuged and dried to obtain ammonium thiocyanate. Reaction equation: CS2 3NH3 = NH4SCN NH4HSNH4HS = nh3-h2s-sulfur method the appropriate amount of water and sulfur powder were stirred in the reactor to form a slurry, the solid sodium cyanide was slowly added in several times, and the reaction was carried out at about 110 ℃, generate sodium thiocyanate, and then add solid ammonium chloride, reaction to generate ammonium thiocyanate, and then add barium thiocyanate in the reaction solution to remove impurity clarification, the supernatant was evaporated under reduced pressure, concentrated and precipitated sodium chloride, and then filtered, cooling crystallization, isolation and drying gave ammonium thiocyanate. Reaction equation: NaCN S = NaSCNNaSCN NH4Cl = NaCl NH4SCN |
solubility in water (g/100ml) | grams dissolved per 100ml of water: 2.15g/20 ℃ |
category | toxic substances |
toxicity grade | poisoning |
Acute toxicity | oral-rat LD50: 2890 mg/kg; Oral-mouse LD: >3000 mg/kg |
flammability hazard characteristics | toxic sulfur oxide and ammonia smoke generated at high temperature |
storage and transportation characteristics | warehouse ventilation and low temperature drying |
fire extinguishing agent | dry powder, foam, sand, carbon dioxide, water mist |
toxic substance data | information provided by: pubchem.ncbi.nlm.nih.gov (external link) |