Preparation and application of dibromohydantoin (DBDMH)

DBDMH (DBDMH)

[Alias] 1,3-dibromo-5,5-dimethylhydantoin

[Structural formula]

[Physical and chemical properties] White or light yellow crystalline powder, slightly soluble in water, soluble in chloroform , ethanol and other organic solvents, easily decomposed in strong acid or strong alkali, stable when dry, with a slight pungent odor; mass fraction ≥98% Melting point: 194～197℃; loss on drying 0.

[Preparation method] There are three methods for preparing dibromohydantoin

① Prepare hypohalite ( sodium hypochlorite , sodium hypobromite ) with alkali and halogen , and then react with dimethyl hydantoin with this halogenating agent, and then neutralize with hydrochloric acid to obtain halogenated hydantoin.

②Using dimethyl sea base as the raw material, adding bromide solution (such as sodium bromide or potassium bromide) and then injecting chlorine gas in the presence of alkali to oxidize the bromide ion in the bromide to bromine for bromination, according to Different proportions can get bromochlorohydantoin and dibromohydantoin;

③Using dimethyl sea as raw material, passing bromine and chlorine in the presence of alkali to obtain halogenated hydantoin

In recent years, scholars at home and abroad have conducted research on process simplification, increased yield, and reduced costs, and some patents have been proposed

Add 152kg of dimethyl hydantoin and 1189kg of water into a 2000L glass-lined reactor, stir at room temperature for 15 minutes, then control the temperature at 5°C, and simultaneously add 290kg of 34.

[technical standard]

[application]

Dibromohydantoin is mainly used as an industrial brominating agent and disinfectant

(1) Swimming pool water disinfection

Adding 1 mg/L of effective bromine dibromohydantoin in the swimming pool water for 1 hour can reduce the total number of bacteria in the water from 1960cfu/mL to 0, and the coliforms from 226300efu/L to less than 10cfu/L

(2) Hospital sewage disinfection

Adding 25mg/L of dibromohydantoin with effective bromine to hospital sewage for 1 hour can reduce the fecal coliform in the sewage from >23800MPN/L before disinfection to below 900MPN/L; it can be separated in undisinfected hospital sewage As for Salmonella and Shigella, none of these bacteria was detected after disinfection, which met the "Sewage Discharge Requirements of Medical Institutions"

(3) Aquaculture disinfectant

It is mainly used for the prevention and treatment of fulminant hemorrhagic disease and gill rotting disease, enteritis, red skin of freshwater fish, etc.

(4) Disinfection in other areas

Disinfect the surface of various objects and tableware, soak, wipe, and spray.