Cyanuric acid, also known as cyanuric acid, chemical formula C3H3N3O3, white crystal, taste slightly bitter, basically non-toxic, soluble in hot water, slightly soluble in cold water, aqueous solution is acidic. Cyanuric acid exists in two isomers, ketone and enol structures, usually as a mixture of the two isomers.
1. Use
In recent years, cyanuric acid has been used more and more widely. In addition to the manufacture of cyanuric acid bromide, chloride, bromine chloride, iodide chloride and cyanuric acid salts and esters, it is also used in the synthesis of new disinfectants, water treatment agents, bleach, chlorination agents, brominating agents, antioxidants, and even directly used as chlorine stabilizer for swimming pools. Nylon, plastic, polyester flame retardant and cosmetic additives and special resin synthesis.
2. Production mode
The production methods of cyanuric acid are mainly divided into pyrolysis method (solid phase method, liquid phase method) and semi-cycle method, and the manufacturers around our company mainly use pyrolysis solid phase production.
(1) Solid phase method: The urea is heated in the furnace by solid phase method (in this process, some manufacturers will add the catalyst ammonium chloride in order to increase the urea absorption rate), and the crude cyanuric acid is obtained by pyrolysis (this product is hard in the bathtub), and then sulfuric acid is added, and the wet product of cyanuric acid is obtained by crushing, hydrolysis and sedimentation (some manufacturers do not centrifuge and dry it, and it comes out of the tank is wet product). Then it is dried to get the finished product (dry cyanuric acid), which is the main method of industrial production of cyanuric acid and consumes about 1.7 tons of urea per ton of product.
(2) Liquid phase method: the organic solvent (dimethylformamide, dimethylacetamide) is heated, under the condition of continuous agitation, urea is added to the solvent in a certain proportion, and after stirring at a certain temperature for a period of time, urea is condensed to obtain a hot slurry mixed with cyanuric acid and organic solubilites. Then, after cooling, precipitation and separation, cyanuric acid filter cake is obtained, and then after washing and drying, cyanuric acid crystal is obtained.
(3) Semi-cycle method: Put cyanuric acid powder into the rolling ball tray, gradually add urea, heat up to a certain temperature, continue for a period of time, stop heating, continue rolling until no ammonia gas is generated. A small part is taken out, crushed, dissolved in sulfuric acid, boiled, centrifuged, filtered, washed and dried to get the finished product.
3, downstream products
Main downstream products of cyanuric acid: (1) Synthetic chlorinated derivatives: trichloroisocyanuric acid (powder solid), sodium dichloroisocyanuric acid or potassium (powder solid). (2) Other uses: mainly used in the production of Seck (solid powder, chemical intermediates), flame retardants (automobile tires).
