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The invention provides a method for manufacturing a bromourea derivative, comprising reacting a salt or adduct of a urea derivative of the general structure A-U, where A stands for an acid and U stands for the urea derivative, with an oxidizer, while combining or mixing aqueous solutions of said urea derivative, of said acid, and of said oxidizer, wherein said urea derivative is in a molar excess over said acid, and the molar ratio of said acid to said oxidizer is at least 1.0. Said urea derivative is in at least four fold molar excess over said acid and at least ten fold excess over said oxidizer, wherein said molar ratio of said acid to said oxidizer is at least 1.0. In a preferred embodiment of the invention, said urea derivative is in at least fifteen fold molar excess over said acid, wherein said molar ratio of said acid to said oxidizer is at least 2.0. In a preferred embodiment of the invention, provided is a method for manufacturing a bromourea derivative comprising reacting a salt or adduct of the general structure A-U, where A stands for HCl or HBr, and wherein U stands for urea. In one aspect of the invention, said A stands for HCl, and the method comprises i) reacting said salt or adduct with NaOCl, thereby forming chlorourea, and ii) adding to said chlorourea a solution comprising NaBr, thereby obtaining a composition comprising bromourea. In another aspect of the invention, said A stands for HBr or a mixture of HBr with HCl, comprising reacting said salt or adduct with NaOCl, resulting in the formation of bromourea and in obtaining a composition comprising bromourea. Said oxidizer is preferably selected from NaOCl, LiOCl, Ca(OCl)2, ClO2, ozone, urea hydroperoxide, hydrogen peroxide, hydrogen peroxide precursors, percarbonates, perborates, peracetates or peroxycarboxylic acids, persulfates, and electrolytically prepared species. The method of the invention comprises, in a preferred embodiment, contacting or mixing of at least two liquid streams, one of which comprises an aqueous solution of said oxidizer. In one aspect of the invention, provided is a method for manufacturing a brominated urea derivative, comprising mixing at least two liquid streams, a first stream comprising an aqueous solution of an adduct or salt of a urea derivative of the general structure A-U, where A stands for HBr, HCl, or a mixture thereof, and U stands for a urea derivative, a second stream comprising an oxidizer. In one embodiment of the invention, the method comprises mixing two streams, a first stream comprising a urea derivative of the general structure A-U where A stands for HBr, and a second stream comprising an oxidizer. In another embodiment of the invention, the method comprises mixing three streams, a first stream comprising a urea derivative of the general structure A-U where A stands for HCl, a second stream comprising an oxidizer, and a third stream comprising bromide anion. In another aspect of the invention, provided is a method for manufacturing bromourea, comprising mixing three liquid streams, a first stream comprising an aqueous solution of an adduct or salt of urea of the general structure A-U, where A stands for an acid other than HBr, and U stands for urea, a second stream comprising an oxidizer, and a third stream comprising bromide ion. In a still other aspect of the invention, provided is a method for manufacturing bromourea, comprising mixing at least two liquid streams, one of the streams comprising an aqueous solution of an adduct or salt of urea of the general structure A-U, where A stands for HBr, HCl, or a mixture thereof, and U stands for urea. In a preferred embodiment of the invention, the method comprises mixing two streams, a first stream comprising an adduct or salt of urea of the general structure A-U where A stands for HBr, and a second stream comprising an oxidizer. In another preferred embodiment of the invention, the method comprises mixing three streams, a first stream comprising an adduct or salt of urea of the general structure A-U where A stands for HCl, a second stream comprising an oxidizer, and a third stream comprising bromide anion. In a preferred embodiment, the method comprises contacting at least two liquid streams, a first stream comprising an aqueous solution of urea hydrobromide in an excess of urea, and a second stream comprising hypochlorite. In other preferred embodiment of the invention, the method comprises mixing three aqueous streams one of which comprises urea hydrochloride, another one comprises hypochlorite, and the third one comprises bromide anion. In a preferred embodiment, the invention is directed to a method for manufacturing bromourea, comprising mixing two aqueous streams, one comprising a salt or adduct of urea of the general structure A-U and the other comprising NaOCl, where A stands for an acid being either HBr or a mixture of HBr with HCl, and U stands for urea, wherein said urea is in a molar excess over said acid, and said acid is in a molar excess over said NaOCl. In another aspect of the invention, provided is a method for manufacturing a bromourea derivative, comprising i) electrolytically treating a salt or adduct of urea of the general structure A-U, where A stands for HCl or HBr, and U stands for urea, thereby providing a mixture comprising chlorourea or bromourea; and if A does not comprise a bromide source ii) reacting said mixture with a bromide source thereby converting said chlorourea to bromourea. When relating to a salt or adduct of urea or urea derivative of the general structure A-U, intended is an equimolar mixture of urea or its derivative with an acid having formula A; in the preferred embodiments of the invention, said salt or adduct is present in the aqueous solution in the presence of an excess of free urea. The term bromourea derivative aims at the same chemical entity as the term brominated urea derivative. The invention relates to a bromourea derivative composition comprising an aqueous solution in which a part of said urea derivative is brominated and a part is not, wherein the non brominated part of said urea derivative is in at least five fold, and preferably in at least ten fold molar excess over the brominated part of said urea derivative. Said brominated urea derivative is preferably obtained in a process comprising reacting a salt or adduct of said urea derivative of the general structure A-U, where A stands for an acid and U stands for said urea derivative, with an oxidizer in a mixture containing said urea derivative, said acid, and said oxidizer, wherein said urea derivative is in at least ten fold molar excess over said acid and in at least twenty fold molar excess over said oxidizer. Said brominated urea derivative is preferably obtained in a process comprising reacting a salt or adduct of urea derivative of the general structure A-U, where A stands for acid selected from HCl or HBr, and U stands for urea derivative, particularly urea, with an oxidizer comprising NaClO in a mixture containing urea derivative, particularly urea, and further containing said acid and said oxidizer, wherein said urea derivative is in at least ten fold molar excess over said acid and in at least twenty fold molar excess over said oxidizer. The invention aims at providing a biocidal composition comprising a urea derivative that is partially brominated, comprising an aqueous mixture containing said urea derivative in non-brominated form, said urea derivative in brominated form, and further chloride, wherein said non-brominated form is in at least three fold molar excess, preferably in at least ten fold molar excess over said brominated form, and in at least three fold molar excess, preferably in at least ten fold molar excess over said chloride. In a preferred embodiment of the invention, said brominated urea derivative composition comprises an aqueous mixture of urea, bromourea, and chloride, wherein said urea is in at least three fold molar excess, preferably in at least ten fold molar excess over said bromourea, and in at least three fold molar excess, preferably in at least ten fold molar excess over said chloride. The invention provides a method of cleaning industrial and agricultural equipment, comprising contacting the surfaces or volumes to be cleaned with an aqueous composition containing a partially brominated urea derivative, wherein the non brominated part of said urea derivative is in at least four fold molar excess over the brominated part of said urea derivative. The invention is directed to the use of said aqueous composition for cleaning an industrial and agricultural equipment, particularly irrigation pipes.
