Colorant treated ion exchange resins, method of making, heat transfer systems and assemblies containing the same, and method of use

Abstract

Disclosed is a colorant treated ion exchange resin comprising at least 15% of exchangeable groups comprising at least one of an ion, a Lewis acid, or a Lewis base resulting from a colorant having a pK a or pK b of greater than 5 in an aqueous solution at 25° C., based on the total number of exchangeable groups. Also disclosed are heat transfer systems, assemblies, fuel cell systems and methods of maintaining a conductivity of less than 200 μS/cm in a heat transfer fluid that employ the disclosed colorant treated ion exchange resins. Finally, a method of making the disclosed colorant treated ion exchange resins is provided.

1 . An ion exchange resin comprising at least 15% by total number of exchangeable groups comprising at least one of an ion, a Lewis acid, or a Lewis base resulting from a colorant having a pK a  or pK b  of greater than 5 in an aqueous solution at 25° C., based on the total number of exchangeable groups. 
     
     
         2 . The ion exchange resin of  claim 1  wherein the colorant is substantially free of functional groups that will form an ionic species due to hydrolysis in an aqueous alcohol solution. 
     
     
         3 . The ion exchange resin of  claim 2  wherein the colorant is substantially free of functional groups selected from the group consisting of carboxylate groups, sulfonate groups, phosphonate groups, quaternary amines, groups that carry a positive charge, and groups that carry a negative charge. 
     
     
         4 . The ion exchange resin of  claim 1  wherein the colorant comprises at least one of the following chromophores: anthraquinone, triphenylmethane, diphenylmethane, azo containing compounds, disazo containing compounds, trisazo containing compounds, diazo containing compounds, xanthene, acridine, indene, phthalocyanine, azaannulene, nitroso, nitro, diarylmethane, triarylmethane, methine, indamine, azine, oxazine, thiazine, quinoline, indigoid, indophenol, lactone, aminoketone, hydroxyketone, stilbene, thiazole, one or more conjugated aromatic groups, one or more conjugated heterocyclic groups, one or more conjugated C—C double bond, or combinations thereof. 
     
     
         5 . The ion exchange resin of  claim 1  wherein the colorant comprises the reaction product of a chromophore and a non-conductive alkoxy radical comprising from 1 to 30 carbons. 
     
     
         6 . The ion exchange resin of  claim 5  wherein the colorant at least one chromophore selected from the group consisting of anthraquinone, triphenylmethane, diphenylmethane, azo containing compounds, disazo containing compounds, trisazo containing compounds, diazo containing compounds, or combinations thereof. 
     
     
         7 . A heat transfer system, comprising
 a circulation loop defining a flow path for a colored heat transfer fluid having a conductivity of less than 10 μS/cm, and   an ion exchange resin positioned in the flow path, the ion exchange resin comprising at least 15% by total number of the exchangeable groups comprising a colorant, based on the total number of the exchangeable groups.   
     
     
         8 . The heat transfer system of  claim 7 , wherein the colored heat transfer fluid comprises a non-conductive colorant and has a conductivity of no more than or equal to 10 μS/cm. 
     
     
         9 . The heat transfer system of  claim 8 , wherein the colored heat transfer fluid has a conductivity of less than 5 μS/cm. 
     
     
         10 . The heat transfer system of  claim 9 , wherein the colored heat transfer fluid has a conductivity from 0.02 to 5 μS/cm. 
     
     
         11 . The heat transfer system of  claim 10 , wherein the colored heat transfer fluid has a conductivity from 0.05 to 1 μS/cm. 
     
     
         12 . The heat transfer system of  claim 8 , wherein the non-conductive colorant is present in an amount of from 0.0001 to 0.2% by weight, based on the total weight of the colored heat transfer fluid. 
     
     
         13 . The heat transfer system of  claim 12 , wherein the non-conductive colorant is present in an amount of from 0.0005 to 0.1% by weight, based on the total weight of the colored heat transfer fluid. 
     
     
         14 . The heat transfer system of  claim 13  wherein the non-conductive colorant is present in an amount of from 0.0005 to 0.05% by weight, based on the total weight of the colored heat transfer fluid. 
     
     
         15 . The heat transfer system of  claim 7  wherein the colored heat transfer fluid further comprises an alcohol. 
     
     
         16 . The heat transfer system of  claim 15  wherein the alcohol is at least one of methanol, ethanol, propanol, butanol, furfurol, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, dipropylene glycol, butylene glycol, glycrol, monoethylether of glycerol, dimethyl ether of glycerol, 1,2,6-hexanetriol, trimethylolpropane, methoxyethanol, or a combination thereof. 
     
     
         17 . The heat transfer system of  claim 8  wherein the colorant in the ion exchange resin and the non-conductive colorant in the colored heat transfer fluid are the same. 
     
     
         18 . The heat transfer system of  claim 17  wherein the colorant is substantially free of functional groups that will form an ionic species due to hydrolysis in an aqueous alcohol solution. 
     
     
         19 . The heat transfer system of  claim 18  wherein the colorant is substantially free of functional groups selected from the group consisting of carboxylate groups, sulfonate groups, phosphonate groups, quaternary amines, groups that carry a positive charge, or groups that carry a negative charge. 
     
     
         20 . The heat transfer system of  claim 17  wherein the colorant comprises at least one of the following chromophores: anthraquinone, triphenylmethane, diphenylmethane, azo containing compounds, disazo containing compounds, trisazo containing compounds, diazo containing compounds, xanthene, acridine, indene, phthalocyanine, azaannulene, nitroso, nitro, diarylmethane, triarylmethane, methine, indamine, azine, oxazine, thiazine, quinoline, indigoid, indophenol, lactone, aminoketone, hydroxyketone, stilbene, thiazole, one or more conjugated aromatic groups, one or more conjugated heterocyclic groups, one or more conjugated C—C double bond, or combinations thereof. 
     
     
         21 . The heat transfer system of  claim 20  wherein the colorant comprises the reaction product of a chromophore and a non-conductive alkoxy compound comprising from 1 to 30 carbons. 
     
     
         22 . The heat transfer system of  claim 21  wherein the colorant comprises the reaction product of at least one chromophore selected from the group consisting of anthraquinone, triphenylmethane, diphenylmethane, azo containing compounds, disazo containing compounds, trisazo containing compounds, diazo containing compounds, or combinations thereof. 
     
     
         23 . A fuel cell system, comprising
 at least one fuel cell comprising an anode, a cathode, and an electrolyte; and   a fuel cell heat transfer system in thermal communication with the at least one fuel cell, comprising
 a circulation loop defining a flow path for a colored liquid heat transfer fluid having a conductivity of less than 10 μS/cm, and 
 an ion exchange resin positioned in the flow path, the ion exchange resin comprising ion exchangeable groups, wherein at least 15% of the total ion exchangeable groups comprise a colorant. 
   
     
     
         24 . A method of maintaining a conductivity of less than 10 μS/cm in a colored heat transfer fluid, comprising first contacting an ion exchange resin with an aqueous colorant solution for a period of time sufficient to exchange at least 15% of the exchange sites with at least one of an ion, a Lewis acid, or a Lewis base resulting from a colorant having a pK a  or pK b  of greater than 5 in an aqueous solution at 25° C. and forming a colorant treated ion exchange resin; and later passing a colored heat transfer fluid through a heat transfer system, wherein the colored heat transfer fluid has a conductivity of less than 10 μS/cm and the heat transfer system comprises a circulation loop defining a flow path for the colored heat transfer fluid and the colorant treated ion exchange resin positioned in the flow path. 
     
     
         25 . The method of  claim 24  wherein the colored heat transfer fluid has a color that is visible to the human eye. 
     
     
         26 . A method of making a colorant treated ion exchange resin, comprising contacting an ion exchange resin with an aqueous colorant solution for a period of time sufficient to exchange at least 15% of the exchange sites with at least one of an ion, a Lewis acid, or a Lewis base resulting from a colorant having a pK a  or pK b  of greater than 5 in an aqueous solution at 25° C. 
     
     
         27 . An assembly powered by an alternative power source comprising
 an alternative power source and   a heat transfer system in thermal communication with the alternative power source, the heat transfer system comprising
 a circulation loop defining a flow path for a heat transfer fluid having a conductivity of less than 200 μS/cm, and 
 an ion exchange resin positioned in the flow path, the ion exchange resin comprising ion exchangeable groups, wherein at least 15% of the total ion exchangeable groups comprise at least one of an ion, a Lewis acid, or a Lewis base resulting from a colorant having a pK a  or pK b  of greater than 5 in an aqueous solution at 25° C., based on the total number of exchangeable groups.