Electrochemical hydroxide systems and methods using metal oxidation

Abstract

There are provided methods and systems for an electrochemical cell including an anode and a cathode where the anode is contacted with a metal ion that converts the metal ion from a lower oxidation state to a higher oxidation state. The metal ion in the higher oxidation state is reacted with hydrogen gas, an unsaturated hydrocarbon, and/or a saturated hydrocarbon to form products.

1 - 68 . (canceled) 
     
     
         69 . A method, comprising:
 contacting an anode with an anode electrolyte in an electrochemical cell wherein the anode electrolyte comprises sodium chloride and metal chloride, wherein the metal chloride comprises metal chloride with metal ion in lower oxidation state and metal chloride with metal ion in higher oxidation state;   contacting a cathode with a cathode electrolyte in the electrochemical cell;   applying a voltage to the anode and the cathode and oxidizing the metal chloride with the metal ion in the lower oxidation state to the metal chloride with the metal ion in the higher oxidation state at the anode;   transferring the anode electrolyte comprising the metal chloride with the metal ion in the lower oxidation state, the metal chloride with the metal ion in the higher oxidation state, and the sodium chloride to a chlorination reaction; and   chlorinating ethylene or ethane with the anode electrolyte comprising the metal chloride with the metal ion in the higher oxidation state in an aqueous medium to form ethylene dichloride, chloroethanol, chloral, and the metal chloride with the metal ion in the lower oxidation state.   
     
     
         70 . The method of  claim 69 , further comprising separating the ethylene dichloride from the chloroethanol, the chloral, and the metal chloride with the metal ion in the lower oxidation state. 
     
     
         71 . The method of  claim 70 , further comprising recirculating the aqueous medium comprising the metal chloride with the metal ion in the lower oxidation state, the metal chloride with the metal ion in the higher oxidation state, and the sodium chloride from the chlorination reaction back to the anode electrolyte in the electrochemical cell. 
     
     
         72 . The method of  claim 69 , further comprising forming an alkali, water, or hydrogen gas at the cathode. 
     
     
         73 . The method of  claim 69 , wherein the cathode electrolyte comprises water and the cathode is an oxygen depolarizing cathode that reduces oxygen and water to hydroxide ions; or the cathode electrolyte comprises water and the cathode is a hydrogen gas producing cathode that reduces water to hydrogen gas and hydroxide ions. 
     
     
         74 . The method of  claim 69 , wherein the metal ion in the metal chloride is selected from the group consisting of iron, chromium, copper, tin, silver, cobalt, uranium, lead, mercury, vanadium, bismuth, titanium, ruthenium, osmium, europium, zinc, cadmium, gold, nickel, palladium, platinum, rhodium, iridium, manganese, technetium, rhenium, molybdenum, tungsten, niobium, tantalum, zirconium, hafnium, and combination thereof. 
     
     
         75 . The method of  claim 69 , wherein the metal ion in the metal chloride is selected from the group consisting of iron, chromium, copper, and tin. 
     
     
         76 . The method of  claim 69 , wherein the metal ion in the metal chloride is copper. 
     
     
         77 . The method of  claim 69 , wherein the lower oxidation state of the metal ion in the metal chloride is 1+, 2+, 3+, 4+, or 5+ and the higher oxidation state of the metal ion in the metal chloride is 2+, 3+, 4+, 5+, or 6+. 
     
     
         78 . The method of  claim 69 , wherein the metal ion in the metal chloride is copper that is converted from Cu +  to Cu 2+ , the metal ion in the metal chloride is iron that is converted from Fe 2+  to Fe 3+ , the metal ion in the metal chloride is tin that is converted from Sn 2+  to Sn 4+ , the metal ion in the metal chloride is chromium that is converted from Cr 2+  to Cr 3+ , the metal ion in the metal chloride is platinum that is converted from Pt 2+  to Pt 4+ , or combination thereof. 
     
     
         79 . The method of  claim 69 , wherein no gas is used or formed at the anode. 
     
     
         80 . The method of  claim 69 , wherein total amount of the metal chloride in the anode electrolyte is between 6-12M. 
     
     
         81 . The method of  claim 69 , wherein the anode electrolyte comprises the metal chloride with the metal ion in the higher oxidation state in range of 4-7M, the metal chloride with the metal ion in the lower oxidation state in range of 0.1-2M, and the sodium chloride in range of 1-3M. 
     
     
         82 . A system, comprising:
 an anode chamber comprising an anode in contact with an anode electrolyte in an electrochemical cell, wherein the anode electrolyte comprises metal chloride and sodium chloride, wherein the metal chloride comprises metal chloride with metal ion in lower oxidation state and metal chloride with metal ion in higher oxidation state, wherein the anode is configured to oxidize the metal chloride with the metal ion in the lower oxidation state to the metal chloride with the metal ion in the higher oxidation state;   a cathode chamber comprising a cathode in contact with a cathode electrolyte in the electrochemical cell;   a power source configured to apply a voltage at the anode and the cathode;   a conduit configured to transfer the anode electrolyte comprising the metal chloride with the metal ion in the lower oxidation state, the metal chloride with the metal ion in the higher oxidation state, and the sodium chloride from the electrochemical cell to a chlorination reactor; and   the chlorination reactor operably connected to the anode chamber of the electrochemical cell through the conduit and configured to chlorinate ethylene or ethane with the anode electrolyte comprising the metal chloride with the metal ion in the higher oxidation state in an aqueous medium to form ethylene dichloride, chloroethanol, chloral, and the metal chloride with the metal ion in the lower oxidation state.   
     
     
         83 . The system of  claim 82 , wherein the cathode electrolyte comprises water and the cathode is an oxygen depolarizing cathode configured to reduce oxygen and water to hydroxide ions; or the cathode electrolyte comprises water and the cathode is a hydrogen gas producing cathode configured to reduce water to hydrogen gas and hydroxide ions. 
     
     
         84 . The system of  claim 82 , further comprising a separator operably connected to the chlorination reactor and configured to separate the ethylene dichloride from the chloroethanol, the chloral, and the metal chloride with the metal ion in the lower oxidation state. 
     
     
         85 . The system of  claim 84 , further comprising a recirculation system operably connected to the separator and the anode chamber of the electrochemical cell and configured to recirculate at least a portion of the aqueous medium from the separator back to the anode electrolyte in the electrochemical cell.