Ammonium thiosulfate is one of the chemicals commonly used in life and industrial production. It is widely used, and its production method and preparation methods are relatively simple. In this article, you will learn in detail the production and preparation methods and main uses of ammonium thiosulfate.
The production preparation method of ammonium thiosulfate
It is produced by treating ammonium sulfite with sulfur at temperatures between 85 and 110°C:
(NH4)2SO3+S→(NH4)2S2O3
1. Add NH3 water into the reaction kettle and pass through SO2 to obtain ammonium sulfite for later use. Add ammonium polysulfide to the reaction kettle, add water to dissolve it, then slowly add the above solution under stirring, react at 30-55 °C, and keep the reaction solution dark orange during the reaction process. The amount of ammonium sulfite solution added is slightly lower than the theoretical amount. After the addition of the ammonium sulfite solution is complete, steam for several hours drives off the ammonium sulfide. The reaction solution was filtered, evaporated under nitrogen protection, and decolorized with activated carbon to remove sulfur. Freezing crystallization, centrifugal dehydration, and drying under the protection of ammonia gas to obtain the finished product.
2. Ammonium sulfite is generated by the action of ammonium bicarbonate, sulfur dioxide, and water, and then reacted with sulfur, filtered, evaporated, cooled, crystallized, and separated to obtain ammonium thiosulfate. Alternatively, add ammonium pentasulfide and excess ammonia water to the ammonium sulfate aqueous solution, filter to remove sulfur after reaction, and then vacuum evaporate at low temperature to obtain ammonium thiosulfate.
3. Add excess ammonium carbonate to calcium thiosulfate aqueous solution, and filter to remove the precipitate. Place the filtrate in a constant temperature water tank at 50°C for two days to decompose excess ammonium carbonate. Then evaporate under reduced pressure at 30°C to concentrate the crystals. The separated crystals are sandwiched between filter papers and dried on phosphorus pentoxide under reduced pressure to obtain anhydrous matter.
4. Mix ammonium bisulfide and ammonium bisulfite aqueous solution according to the ratio of accurate substance molar ratio of 1:2 and react at room temperature to generate ammonium thiosulfate. A small amount of sulfur was also precipitated during the reaction, and the sulfur was precipitated by heating in a water bath and removed by filtration. The filtrate was evaporated and concentrated according to the same steps as the previous method, and the separated crystals were clamped in filter paper to dry.
Application of ammonium thiosulfate
1. Ammonium thiosulfate is used in photographic fixers. It is a so-called fast fixer that acts faster than a sodium thiosulfate fixer. Fixation involves these chemical reactions:
AgBr+2(NH4)2S2O3→(NH4)3[Ag(S2O3)2]+NH4Br
AgBr+3(NH4)2S2O3→(NH4)5[Ag(S2O3)3]+NH4Br
2. Ammonium thiosulfate is also used for gold and silver leaching. It works because copper is present here as a catalyst. This method of gold cyanidation is harmless. The advantage of ammonium thiosulfate is that the pyrolysis of its silver complex leaves only silver sulfide residues, rather than complexes formed from sodium thiosulfate.
3. Ammonium thiosulfate can also be used as fertilizer. An excellent nitrogen fertilizer (commonly known as fertilizer powder), suitable for general soil and crops, can make branches and leaves grow vigorously, improve fruit quality and yield, and enhance the disaster resistance of crops. It can be used as base fertilizer and top dressing.
4. According to some research investigations, it can also be used as an additive in coal-waste combinations to prevent the generation of dioxins and furans during combustion.
5. Catalyst for food caramel color, nitrogen source for yeast culture in fresh yeast production, dyeing aid for acid dyes, deliming agent for leather. In addition, it is used in beer brewing, chemical reagents, and battery production.
6. Rare earth mining: Ammonium sulfate is used to exchange rare earth elements in mineral soil by ion exchange.
7. For polyprotein purification process.
8. Industry: It can be used as a developer, bleaching agent, deodorant, etc. In addition, it can be used in the processing of textiles, leather goods, and paper.
In the end
Ammonium thiosulfate is widely used, and its production and preparation methods are diverse and simple. Jinbangch has many years of experience in manufacturing and selling ammonium thiosulfate. We can provide ammonium thiosulfate in various contents and grades, contact us now, we will provide free samples and the biggest price discount.