Sorbic acid and/or its derivatives, such as potassium sorbate, as a preventative for rust, corrosion and scale on metal surfaces

Abstract

An aqueous solution that will prevent rust, corrosion and scale on metal surfaces that includes potassium sorbate at percentages above 0.3%. This aqueous solution is effective at pH 4.5. However, its optimum effectiveness as a rust preventive is at pH 6.0 and above. The solution can be produced in a concentrated form and then diluted with tap or deionized water. The potassium sorbate solution has reduced conductivity and reduced oxygen content, both relative to tap water. This is believed to be the technical basis for its ability to prevent rust. Furthermore, the combination of lower conductivity and reduced oxygen content renders the potassium sorbate solution less viable for microbiological growth which prevents the solution from becoming rancid when it is used in re-circulating water systems. This also permits the use of toxic biocides to be eliminated in re-circulatory water systems, which are often used to reduce and control microbiological growth. Also, the solution can be substituted for tap water in water-based products, such as paints, which eliminates the need to plate the cans.

1 . An aqueous solution that prevents the formation of rust, corrosion and scale on metal surfaces that are exposed to it comprising: 
 potassium sorbate dissolved in tap water or deionized water at a concentration of 0.3 %, by weight, or higher, the aqueous solution having a pH of 4.5 or higher.    
     
     
         2 . The aqueous solution as set forth in  claim 1  in which the concentration of potassium sorbate is in the range of 0.30% to 1.75%.  
     
     
         3 . A concentrated form of aqueous solution that, when diluted with 16 parts of tap water or deionized water, prevents the formation of rust, corrosion and scale on metal surfaces that is exposed to it comprising a solution formed in accordance with the following ratio of ingredients: 
 269.5 milligrams of tap or deionized water;    0.5 milligrams of sodium nitrate; and    270.0 milligrams of potassium sorbate.    
     
     
         4 . The method of producing a concentrated form of aqueous solution for use as a rust preventor comprising the steps of: 
 a) providing 269.5 milligrams of tap or deionized water to a mixing container;    b) adding 0.5 milligrams of sodium nitrate to the mixing container;    c) adding 270.0 milligrams of potassium sorbate to the mixing container; and    d) mixing the contents of the mixing container.    
     
     
         5 . The method of producing a aqueous solution for use as a rust preventor comprising the steps of: 
 a) providing a multiple of 269.5 milligrams of tap or deionized water to a mixing container;    b) adding 0.5 milligrams, multiplied by the same multiple, of sodium nitrate to the mixing container;    c) adding 270.0 milligrams, multiplied by the same multiple, of potassium sorbate to the mixing container; and    d) diluting the contents of the mixing container with 16 parts of tap or deionized water.