production method
The phosphorus oxychloride method uses phosphorus oxychloride as a raw material, aluminum trichloride as a catalyst, and is heated at a temperature of about 80°C, and hydrogen bromide gas is introduced to react to obtain phosphorus oxybromide.
The hydrogen chloride gas generated by the reaction is absorbed by water to generate dilute hydrochloric acid.
Phosphorus tribromide method In a round-bottomed flask equipped with a ground-mouth reflux condenser, add a mixture of phosphorus pentabromide and phosphorus pentoxide (250gPBr5/about 30gP2O5), and slowly heat to 150℃. Phosphorus pentoxide is chemically The metering is slightly more than that of phosphorus pentabromide. At this time, while paying attention to expelling bromine, the reaction is completed within 5 hours. Next, 10 g of bromine and a corresponding amount of phosphorus pentoxide were added to the molten material, and refluxed at 150°C for several hours. This is because it takes time for the intermediate product phosphorus tribromide to oxidize to phosphorus pentabromide and to transform to phosphorus oxybromide. The product was vacuum distilled under reduced pressure. After removing the bromine and phosphorus tribromide contained in the initial fraction, it is collected. The receiver is cooled with ice brine.