Process for generating stabilized bromine compounds

Details Process for generating stabilized bromine compounds Process for generating stabilized bromine compounds

2001-04-16

2003-12-09

Pryor, Alton N. (Department: 1616)

Drug, bio-affecting and body treating compositions

Inorganic active ingredient containing

Elemental sulfur or compound thereof

C424S615000, C424S663000, C424S665000, C424S680000, C424S688000, C424S723000

Reexamination Certificate

active

06660307

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for producing and stabilizing active bromine solutions and, more particularly, to a method for producing an active bromine solution from a bromate salt solution with sulfamic acid.
2. Description of the Related Art
A typical process for producing bromine has been described. For example, European Patent Application Publication No. 476,862 teaches that an aqueous solution containing bromide ions may be electrolyzed under acidic conditions to produce a bromine solution. Also, equivalent bromine, as hypobromous acid, has been formed by electrolyzing a solution containing chloride and bromide ions as described in European Patent No. 391,924.
Other processes for producing bromine have been described, for example, by Blum et al., in U.S. Pat. Nos. 5,679,239, 5,868,911, and 6,165,343. Blum et al. teach a process for generating an aqueous active bromine solution by electrolyzing an aqueous solution containing bromide ions until bromate ions are formed and adding acid to the aqueous solution containing the bromate ions to generate an aqueous solution containing the active bromine compounds. Additionally, Belohlav et al., in U.S. Pat. No. 3,222,276, teach a bromination process which mixes metered quantities of a bromide-bromate salt solution and a mineral acid to liberate elemental bromine.
Howarth et al., in U.S. Pat. No. 5,385,650, describe a process for recovering bromine from acidic alkaline metal bromide and hydrobromic acid solutions. Howarth et al. teach that a process for recovery of bromine involving passing an electric current through an acidic solution thereby generating bromine by electrolysis to produce an electrolyzate containing bromine. Bromine may be separated from the electrolyzate as a vapor under negative pressure.
Aqueous bromine solutions are typically unstable and readily decompose. Accordingly, efforts have been focused on improving the stability of active bromine-containing solutions. For example, Goodenough et al., in U.S. Pat. No. 3,558,503, teach of a stable bromo-sulfamates composite which comprises a bromine stabilizer such as biuret, succinimide, urea and lower aliphatic mono- and di-substituted ureas, sulfamic acid and alkyl sulfonamides with the general formula RSO
3
NH
2
with sufficient hydroxide additive to provide a pH of about 8 to about 10. Trulear, in U.S. Pat. No. 4,759,852, teaches using sulfamic acid to inhibit phosphonate decomposition in chlorine-bromine mixtures. Meier et al., in U.S. Pat. No. 4,929,424, similarly teach of a method for inhibiting the corrosion of metal surfaces in contact with halogenated water vapor by adding sulfamic acid. Also, Moore, Jr. et al., in U.S. Pat. No. 6,068,861, teach of preparing aqueous bromine solutions by mixing bromine-chloride or bromine with an aqueous solution of an alkali metal salt of sulfamic acid at a pH of at least about 7.
BRIEF SUMMARY OF THE INVENTION
The present invention is directed to a method for producing an active bromine solution comprising the steps of providing a solution comprising a bromate salt, adding an amino-complexing agent to the solution, adjusting a pH of the solution to below about 1, adding a halide salt to the solution and adjusting the pH of the solution to at least about 4.
In another embodiment, the present invention is directed to a method for producing a biocide solution comprising the steps of adding at least one of a sulfamate salt and sulfamic acid to a solution comprising a bromate salt, adding a halide salt to the solution, adding sulfuric acid to the solution to produce the biocide solution and adding sodium hydroxide to the biocide solution while maintaining the biocide solution at less than about 30° C.
In another embodiment, the present invention is directed to a biocide additive kit comprising a first solution comprising a bromate salt and a bromide salt, a second solution comprising an amino-complexing agent and a mineral acid and a third solution comprising an alkali.
In another embodiment, the present invention is directed to a process for producing an active bromine solution comprising the steps of providing a solution comprising a bromate salt, adding a halide salt to the solution, adding an amount of an amino-complexing agent to produce a bromate to amino-complexing agent molar ratio of at least about 3:1 to the solution, adding an amount of a mineral acid to adjust a pH of the solution to less than about 1, adding an amount of an alkali to raise the pH of the solution to between about 4 and about 10 and maintaining the solution at less than about 30° C.
In another embodiment, the present invention is directed to a biocide additive kit comprising a first solution comprising a bromate salt, a second solution comprising an amino-complexing agent, a third solution comprising a halide salt, a fourth solution comprising a mineral acid and a fifth solution comprising an alkali.
In another embodiment, the present invention is directed to a method for producing a biocide solution comprising the steps of adding at least one of a sulfamate salt and sulfamic acid to a solution comprising a bromate salt and a halide salt, adding sulfuric acid to produce the biocide solution and adding sodium hydroxide to the biocide solution while maintaining the biocide solution at less than about 30° C.
In another embodiment, the present invention is directed to a method for producing an active bromine solution comprising the steps of providing a solution comprising a bromate salt and a halide salt, adding an amino-complexing agent, adjusting a pH of the solution to below about 1 and adjusting the pH of the solution to at least about 4.
In another embodiment, the present invention is directed to a system for producing a biocide comprising a vessel in fluid communication with a first reservoir comprising a bromate salt solution, a second reservoir in fluid communication with the vessel and comprising an amino-complexing agent solution and a third reservoir in fluid communication with the vessel and comprising an alkali.
DETAILED DESCRIPTION
The present invention is directed to a method for producing and stabilizing active bromine-containing solution by reacting bromate and bromide salts with an amino-complexing agent at low pH and raising the pH to at least about 4. The active bromine-containing solution may be used as for the onsite-treatment of water such as industrial water wastewater, sewage, pools and hot tubs. Other uses of the generated solution would be apparent to those skilled in the art.
As used herein, an active bromine compound is meant to include brominated biocide compounds, and solutions thereof, having oxidative or biocide properties. A solution containing an active bromine compound may comprise any of hypobromous acid, HOBr, hypobromate salt such as sodium hypobromate, NaOBr, and bromine, Br
2
, hypobromite ion, hydrogen tribromide and bromine chloride. In addition, stability is meant to be the ability of a solution to resist degradation because of aging, and, in this context, the ability to retain the initial active bromine equivalent. The active bromine equivalent of a solution may be determined by any method known in the art including, for example, iodine titration. A biocide is any substance that is toxic or lethal to living organisms, such as a pesticide, herbicide, or fungicide, and in this context, a biocide solution may be an active bromine-containing solution.
A bromate solution may be produced by electrolyzing a bromide salt, for example, sodium bromide, NaBr, in alkaline conditions to produce an aqueous solution containing bromate salts. Such a process has been described by Blum et al., in U.S. Pat. Nos. 5,679,239, 5,868,911 and 6,165,343, each of which are incorporated by reference in their entireties.
The aqueous solution containing the bromate salts may then be used to produce an active bromine-containing solution. Typically, the bromate salt containing solution also comprises halide salts. Preferably, the halide is a bromide salt such as sodium bromide.

Affiliated with

Also associated with

Rating

Process for generating stabilized bromine compounds does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Process for generating stabilized bromine compounds, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for generating stabilized bromine compounds will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3172082