Abstract:

An aqueous solution of dibromohydantoin （DBDMH） whose concentration was 25.3 g/L was prepared with sulfamic acid as the stabilizer. The UV absorption spectrum, stability and bactericidal activity of this solution were examined. The experimental results show that, there is an absorption peak at the wavelength of 280 nm, indicating that covalent bonds have been formed between the nitrogen atoms in the sulfamic acid molecules and part of active bromine atoms in the DBDMH molecules. This can reduce the release of the active bromines and help to stabilize the DBDMH in the water. The results of stability test reveal that the solution is very stable. It is found that the solution containing 1 000 mg/L DBDMH shows superior disinfection effects against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. The solution containing 2 500 mg/L DBDMH shows superior disinfection effects against Candida albicans in the suspension. The results of the spot test show that the solution of DBDMH also shows good disinfection effects against natural germs.

Key words: DBDMH, sulfamic acid, disinfector, disinfection effect