Co2 utilization in electrochemical systems

Abstract

A low-voltage, low-energy electrochemical system and method of removing protons and/or producing a base solution comprising hydroxide and carbonate/bicarbonate ions, utilizing carbon dioxide in a cathode compartment that is partitioned into a first cathode electrolyte compartment and a second cathode electrolyte compartment such that liquid flow between the cathode electrolyte compartments is possible, but wherein gaseous communication to between the cathode electrolyte compartments is restricted. Carbon dioxide gas in one cathode electrolyte compartment is utilized with the cathode electrolyte in both compartments to produce the base solution with less that 3V applied across the electrodes.

1 . An electrochemical system comprising:
 a cathode compartment partitioned into a first cathode electrolyte compartment and a second cathode electrolyte compartment by a partition wherein,   cathode electrolyte in the second cathode electrolyte compartment is in contact with a cathode; and   anode electrolyte in an anode compartment is in contact with an anode.   
     
     
         2 . The system of  claim 1 , wherein cathode electrolyte in the first cathode electrolyte compartment contacts cathode electrolyte in the second cathode electrolyte compartment. 
     
     
         3 . The system of  claim 2 , wherein cathode electrolyte in the first cathode electrolyte compartment comprises a gas. 
     
     
         4 . The system of  claim 3 , wherein the gas comprises carbon dioxide. 
     
     
         5 . The system of  claim 4 , wherein the gas is absorbed into the cathode electrolyte. 
     
     
         6 . The system of  claim 4 , wherein the carbon dioxide gas is isolated from cathode electrolyte in the second cathode electrolyte compartment. 
     
     
         7 . The system of  claim 5 , wherein the cathode electrolyte in the first cathode electrolyte compartment comprises hydroxide ions, carbonic acid, carbonate ions and/or bicarbonate ions. 
     
     
         8 . The system of  claim 1 , wherein cathode electrolyte in the second cathode electrolyte compartment comprises dissolved carbon dioxide. 
     
     
         9 . The system of  claim 7 , wherein cathode electrolyte in the second cathode electolyte compartment comprises hydroxide ions, carbonic acid, carbonate ions and/or bicarbonate ions. 
     
     
         10 . The system of  claim 4 , wherein the system is configured to produce to hydroxide ions in the second cathode electrolyte compartment with less than 2V applied across the anode and cathode. 
     
     
         11 . The system of  claim 10 , wherein the system is configured to produce hydrogen gas at the cathode. 
     
     
         12 . The system of  claim 11 , wherein the system does not produce a gas at the anode. 
     
     
         13 . The system of  claim 12 , wherein the system is configured to migrate hydroxide ions from the second cathode electrolyte compartment to the first cathode electrolyte compartment. 
     
     
         14 . The system of  claim 12 , further comprising a hydrogen gas delivery system configured to direct hydrogen gas produced at the cathode to the anode. 
     
     
         15 . The system of  claim 1 , wherein the first cathode electrolyte compartment is operatively connected to an industrial waste gas system. 
     
     
         16 . The system of  claim 15 , wherein the industrial waste gas system comprises carbon dioxide. 
     
     
         17 . The system of  claim 16 , wherein the carbon dioxide is derived from combusting fossil fuels. 
     
     
         18 . The system of  claim 13 , wherein the cathode compartment is operatively connected to a waste gas treatment system. 
     
     
         19 . The system of  claim 18 , wherein the waste gas system comprises carbon dioxide. 
     
     
         20 . The system of  claim 1 , wherein the cathode compartment is operatively connected to a hydroxide, carbonate and/or bicarbonate precipitation system. 
     
     
         21 . The system of  claim 20 , wherein the precipitation system is configured to utilize the cathode electrolyte to produce hydroxide, carbonates and/or divalent cation bicarbonate. 
     
     
         22 . The system of  claim 4 , wherein the anode and cathode are operatively connected to an off-peak electrical power-supply system. 
     
     
         23 . The system of  claim 4 , further comprising an ion exchange membrane between the anode compartment and the cathode compartment. 
     
     
         24 . The system of  claim 23 , wherein the ion exchange membranes comprises a cation exchange membrane separating the cathode electrolyte in the second cathode electrolyte compartment from a third electrolyte. 
     
     
         25 . The system of  claim 23 , wherein the ion exchange membrane comprises an anion exchange membrane separating the anode electrolyte from the third electrolyte. 
     
     
         26 . The system of  claim 25 , wherein the third electrolyte comprises sodium ions and chloride ions. 
     
     
         27 . The system of  claim 26 , wherein the system is configured to migrate sodium ions from the third electrolyte to cathode electrolyte through the cation exchange membrane, and migrate chloride ions from the third electrolyte to the anode electrolyte through the anion exchange membrane. 
     
     
         28 . The system of  claim 26 , wherein the system is configured to produce sodium hydroxide in the cathode electrolyte. 
     
     
         29 . The system of  claim 26 , wherein the system is configured to produce sodium hydroxide, sodium carbonate and/or sodium bicarbonate in the cathode electrolyte. 
     
     
         30 . The system of  claim 26 , wherein the system is configured to produce partially desalinated water in the third electrolyte. 
     
     
         31 . The system of  claim 29 , wherein the partially desalinated water is operatively connected to a water treatment system. 
     
     
         32 . The system of  claim 26 , wherein the system is configured to produce hydrochloric acid in the anode electrolyte. 
     
     
         33 . The system of  claim 26 , wherein the cathode electrolyte is operatively connected to a first carbon dioxide gas/liquid contactor configured to dissolve carbon dioxide in the cathode electrolyte. 
     
     
         34 . The system of  claim 10 , wherein the system is configured to produce a pH differential of between 0 and 14 or greater pH units between the anode and cathode electrolytes. 
     
     
         35 . An electrochemical method comprising:
 directing a gas into cathode electrolyte in a first cathode electrolyte compartment; and   applying a voltage across a cathode in contact with cathode electrolyte in a second cathode electrolyte compartment that is partitioned from the first cathode electrolyte compartment, and an anode in contact with an anode electrolyte.   
     
     
         36 . The method of  claim 35 , wherein the gas comprises carbon dioxide. 
     
     
         37 . The method of  claim 36 , comprising producing hydroxide ions, carbonic acid, carbonates ions and/or bicarbonate ions in the first cathode electrolyte compartment. 
     
     
         38 . The method of  claim 36 , comprising producing carbonate ions and/or bicarbonate ions in the second cathode electrolyte compartment. 
     
     
         39 . The method of  claim 37 , comprising producing hydrogen gas at the cathode. 
     
     
         40 . The method of  claim 39 , comprising producing hydrogen ions at the anode. 
     
     
         41 . The method of  claim 40 , wherein a gas is not produced at the anode. 
     
     
         42 . The method of  claim 41 , further comprising directing hydrogen gas produced at the cathode to the anode. 
     
     
         43 . The method of  claim 35 , wherein the voltage is less than 2V. 
     
     
         44 . The method of  claim 42 , further comprising separating the cathode electrolyte from a third electrolyte by a cation exchange membrane. 
     
     
         45 . The method of  claim 38 , further comprising separating the anode electrolyte from the third electrolyte by an anion exchange membrane. 
     
     
         46 . The method of  claim 45 , wherein the third electrolyte comprises sodium and chloride ions. 
     
     
         47 . The method of  claim 45 , further comprising migrating sodium ions from the third electrolyte to the cathode electrolyte across the cation exchange membrane, and migrating chloride ions from the third electrolyte to the anode electrolyte across the anion exchange membrane. 
     
     
         48 . The method of  claim 47 , wherein the cathode electrolyte comprises sodium carbonate, sodium bicarbonate or sodium hydroxide, and the anode electrolyte comprises hydrochloric acid. 
     
     
         49 . The method of  claim 48 , comprising producing an acid in the anode electrolyte. 
     
     
         50 . The method of  claim 49 , comprising utilizing the acid to dissolve a mafic mineral or a cellulose material. 
     
     
         51 . The method of  claim 48 , comprising producing partially desalinated water in the third electrolyte. 
     
     
         52 . The method of  claim 48 , further comprising contacting the cathode electrolyte with a divalent cation solution to produce divalent cation hydroxide, carbonate and/or bicarbonate compounds. 
     
     
         53 . The method of  claim 52 , wherein the divalent carbonate and/or bicarbonate compounds comprise calcium and magnesium. 
     
     
         54 . The method of  claim 52 , further comprising:
 withdrawing a first portion of the cathode electrolyte;   dissolving carbon dioxide in the first portion of cathode electrolyte to produce a first enriched carbonated cathode electrolyte; and   replenishing cathode electrolyte with the first enriched carbonated cathode electrolyte.   
     
     
         55 . The method of  claim 54 , further comprising:
 withdrawing a second portion of the cathode electrolyte;   dissolving carbon dioxide in the second portion of cathode electrolyte to produce a second enriched carbonated cathode electrolyte; and   contacting the second enriched carbonated cathode electrolyte with a divalent cation solution to produce divalent cation carbonates.   
     
     
         56 . The method of  claim 35 , comprising applying an off-peak electrical power-supply across the cathode and anode to provide the voltage across the anode and cathode.