DBNPA, active ingredient chemical name is dibromocyanoaceta mide or dibromonitrilopropio namide. (DBNPA) is a biocide, used in paper industry and as preservatives for coatings and slurries and to control microbial fouling in paper mills and process water systems. DBNPA is a quick kill biocide which quickly hydrolyzies under both acid and alkaline conditions. It is preferred for its instability in water as it quickly kills and then quickly degrades to ammonia and bromide ion.
The facile reaction of DBNPA with microbially important, sulfur-containing nucleophiles such as glutathione or cysteine is the basis of its mode of antimicrobial action; it is not classified as an oxidizing or halogen-releasing biocide.
Unlike typical thiol-reactive biocides, its action is such that thiol-based amino acids like cystiene and penicillamine are oxidized beyond the formation of disulfide species.5 By irreversibly disrupting the function of cell-surface components, transport across cell membranes is precluded, and key biological functions are inhibited. DBNPA offers an advantageous combination of rapid degradation to relatively non-toxic end products, and even faster microbial kill at low ppm concentrations.
DBNPA, when formulated as a 20% solution in water and polyethylene glycol (DOWICIL QK-20), is completely miscible with water and readily disperses upon introduction into a waterborne system.
The DBNPA molecule begins functioning as an antimicrobial agent immediately upon introduction into a system; the rate of this activity is not affected by pH, and antimicrobial control is usually achieved before complete degradation occurs. The combination of instantaneous antimicrobial activity and rapid chemical breakdown makes DBNPA both a cost-effective and environmentally friendly biocide
DBNPA liquid is widely used in pulp and paper water treatment applications. It is less widely used in cooling water due to its high cost relative to other agents.
The liquid formulations of DBNPA contain DBNPA (white solid), sodium bromide, hydrobromic acid, hypobromous acid, tetraethylene glycol, and water. The liquid formulation is an oxidizing formulation and is similar to bleach and sodium bromide-bleach combinations. The liquid formulation is oxidizing because of the hypobromous acid in the formulation.
DBNPA solid slow release form is very cost effective relative to isothiazolinones, the most expensive biocides and requires no metering equipment, special feeders, and one tablet can last up to 3 weeks!
Glutaraldehyde and DBNPA: An Effective Combination Treatment Program for the Control of Microbial Growth in Cooling Water Systems. The use of biocide combinations has found increased use over the years in combating microbial problems within cooling water systems.
The use of two or more biocides in combination offers both greater broad-spectrum control, as well as limiting the possibility of tolerance development due to the use of one biocide alone. A particularly effective biocide combination is glutaraldehyde, fed on an intermittent basis, along with a continuous low dose of DBNPA (2,2-dibromo-3-nitrilopropionamide). The low dose of DBNPA can either be fed as a liquid, or more conveniently, via a solid, slow release tablet. |
