Corrosion resistance of industrial brine solutions

Abstract

An industrial brine which exhibits improved corrosion inhibition which contains a carbohydrate having a molecular weight in the range of about 180 to 342 and where said carbohydrate is present in a concentration sufficient to reduce the corrosion rate of said brine by at least about 70%. The brine includes chloride salts such as magnesium chloride, calcium chloride, sodium chloride and mixtures thereof.

1 . A method of inhibiting the corrosion of iron, steel and other ferrous alloys exposed to brines, both man made and naturally occurring, by the addition to said brine of an effective amount of a carbohydrate having a molecular weight in the range of about 150 to 1476 with said carbohydrate being at least one from the group consisting of monosaccharides, both aldoses and ketoses, as well as disaccharides to nonasaccharides and mixtures thereof. 
   
   
       2 . The method of  claim 1  in which the aldoses as represented by glucose and galactose. 
   
   
       3 . The method of  claim 1  in which the ketoses are represented by fructose and sorbose. 
   
   
       4 . The method of  claim 1  in which the carbohydrate mixtures have dextrose equivalents (DE values) of 18 to 66. 
   
   
       5 . The method of  claim 1  in which concentration of carbohydrates is 3% to 60% by weight. 
   
   
       6 . An industrial brine which exhibits improved corrosion inhibition which contains a carbohydrate having a molecular weight in the range of about 180 to 342 and where said carbohydrate is present in a concentration sufficient to reduce the corrosion rate of said brine up to about 70%. 
   
   
       7 . The brine of  claim 6  in which the carbohydrate is at least one selected from the group consisting of sorbose, fructose and glucose. 
   
   
       8 . The brine of  claim 6  in which the carbohydrate is a ketose sugar. 
   
   
       9 . The brine of  claim 6  in which the corrosion rate of said brine is in the range of about 13 to 39 mils/yr. 
   
   
       10 . The brine of  claim 6  in which the corrosion rate of said brine is in the range of about 13 to 24 mils/yr. 
   
   
       11 . The brine of  claim 6  in which the carbohydrate is at least one of the group consisting of sorbose and fructose and where the corrosion rate of said brine is less than about 15 mils/yr. 
   
   
       12 . A method of reducing the corrosion rate of an industrial brine which comprises adding at least 3 wt % of a low molecular weight carbohydrate with said carbohydrate having a molecular weight in the range of about 180 to 342. 
   
   
       13 . The method of  claim 12  in which the carbohydrate is at least one selected from the group consisting of sorbose, fructose and glucose. 
   
   
       14 . The method of  claim 12  in which the carbohydrate is a ketose sugar. 
   
   
       15 . The method of  claim 12  in which the corrosion rate of said brine is in the range of about 13 to 39 mils/yr. 
   
   
       16 . The method of  claim 12  in which the corrosion rate of said brine is in the range of about 13 to 24 mils/yr. 
   
   
       17 . The method of  claim 12  in which the carbohydrate is at least one of the group consisting of sorbose and fructose, and where the corrosion rate of said brine is less than about 15 mils/yr. 
   
   
       18 . An industrial brine which contains calcium chloride and which further includes a carbohydrate having a molecular weight in the range of about 180 to 342 and where said carbohydrate is present in a concentration sufficient to reduce the corrosion rate of said brine by at least about 20%. 
   
   
       19 . The brine of  claim 18  in which the carbohydrate is at least one selected from the group consisting of sorbose, fructose and glucose. 
   
   
       20 . The brine of  claim 18  in which the carbohydrate is a ketose sugar. 
   
   
       21 . The brine of  claim 18  in which the corrosion rate of said brine is in the range of about 13 to 39 mils/yr. 
   
   
       22 . The brine of  claim 18  in which the corrosion rate of said brine is in the range of about 13 to 24 mils/yr. 
   
   
       23 . The brine of  claim 18  in which the carbohydrate is at least one of the group consisting of sorbose and fructose and where the corrosion rate of said brine is less than about 15 mils/yr. 
   
   
       24 . A method of reducing the corrosion rate of a calcium chloride containing industrial brine which comprises adding at least 3 weight % of a low molecular weight carbohydrate with said carbohydrate having a molecular weight in the range of about 180 to 342. 
   
   
       25 . The method of  claim 24  in which the carbohydrate is at least one selected from the group consisting of sorbose, fructose and glucose. 
   
   
       26 . The method of  claim 24  in which the carbohydrate is a ketose sugar. 
   
   
       27 . The method of  claim 24  in which the corrosion rate of said brine is in the range of about 13 to 39 mils/yr.