Formulations containing a non-oxidative biocide and a source of active halogen and use thereof in water treatment

Abstract

Novel formulations containing a non-oxidative biocide, such as DBNPA, and a source of an in situ produced active biocide, such as a concentrated aqueous solution of an inorganic halide salt, are disclosed. These novel formulations are particularly effective in the treatment of water, and are characterized by high stability, desirable rheological properties and an excellent biocidal activity.

1 .- 53 . (canceled) 
     
     
         54 . A method of treating an aqueous composition which comprises:
 a) introducing to an aqueous composition for which biocidal treatment is desired a liquid formulation comprising at least one non-oxidative biocide and a concentrated aqueous solution of an inorganic halide salt that produces an active halogen upon activation by an oxidizer; and,   b) introducing to the aqueous composition an oxidizer that activates the inorganic halide salt component of the liquid formulation to produce an active halogen in situ, the oxidizer being introduced to the aqueous composition prior to, with and/or following introduction of liquid formulation to the aqueous composition, the amount of liquid formulation and oxidizer introduced to the aqueous composition being effective to kill, prevent or inhibit the growth of microorganisms therein.   
     
     
         55 . The method of  claim 54  wherein the non-oxidative biocide is at least one member selected from the group consisting of bronopol and 2,2-dibromo-3-nitrilopropionamide. 
     
     
         56 . The method of  claim 54  wherein the oxidizer is at least one member selected from the group consisting of chlorine, bromine, hypochlorite salt, hypochlorous acid, hypobromite salt, hypobromous acid, a halogenated hydantoin, a halogenated isocyanurate, a peroxide and a persulfate. 
     
     
         57 . The method of  claim 54  wherein the liquid formulation further comprises a solvent. 
     
     
         58 . The method of  claim 57  wherein the organic solvent is a glycol. 
     
     
         59 . The method of  claim 58  wherein the glycol is a polyalkylene glycol. 
     
     
         60 . The method of  claim 59  wherein the polyalkylene glycol is a polyethylene glycol. 
     
     
         61 . The method of  claim 54  wherein the aqueous composition for which biocidal treatment is desired is at least one member selected from the group consisting of drinking water, sewage water, process water used in papermaking, process water used in industrial cooling, washing water, heavy oil sludge, cutting oil, lignin-containing liquor and textile oil. 
     
     
         62 . The method of  claim 61  wherein the non-oxidative biocide is at least one member selected from the group consisting of bronopol and 2,2-dibromo-3-nitrilopropionamide. 
     
     
         63 . The method of  claim 61  wherein the oxidizer is at least one member selected from the group consisting of chlorine, bromine, hypochlorite salt, hypochlorous acid, hypobromite salt, hypobromous acid, a halogenated hydantoin, a halogenated isocyanurate, a peroxide and a persulfate. 
     
     
         64 . The method of  claim 61  wherein the liquid formulation further comprises a solvent. 
     
     
         65 . The method of  claim 64  wherein the organic solvent is a glycol. 
     
     
         66 . The method of  claim 65  wherein the glycol is a polyalkylene glycol. 
     
     
         67 . The method of  claim 66  wherein the polyalkylene glycol is a polyethylene glycol. 
     
     
         68 . The method of  claim 61  wherein the inorganic halide salt is sodium bromide and the oxidizer is at least one member selected from the group consisting of hypochlorite salt and hypochlorous acid. 
     
     
         69 . The method of  claim 68  wherein the non-oxidative biocide is at least one member selected from the group consisting of bronopol and 2,2-dibromo-3-nitrilopropionamide. 
     
     
         70 . A method of treating an aqueous composition which comprises:
 a) introducing to at least one aqueous composition selected from the group consisting of drinking water, sewage water, process water used in papermaking, process water used in industrial cooling, washing water, heavy oil sludge, cutting oil, lignin-containing liquor and textile oil for which biocidal treatment is desired a liquid formulation comprising at least one non-oxidative biocide selected from the group consisting of bronopol and 2,2-dibromo-3-nitrilopropionamide, and a concentrated aqueous solution of sodium bromide; and,   b) introducing to the aqueous composition at least one oxidizer selected from the group consisting of hypochlorite salt and hypochlorous acid, the oxidizer activating the sodium bromide to produce an active bromide in situ, the oxidizer being introduced to the aqueous composition prior to, with and/or following introduction of liquid formulation to the aqueous composition, the amount of liquid formulation and oxidizer introduced to the aqueous composition being effective to kill, prevent or inhibit the growth of microorganisms therein.   
     
     
         71 . The method of  claim 70  wherein the liquid formulation further comprises a solvent. 
     
     
         72 . The method of  claim 71  wherein the solvent is a polyalkylene glycol. 
     
     
         73 . The method of  claim 72  wherein the polyalkylene glycol is a polyethylene glycol.