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 - 28 . (canceled) 
     
     
         29 . A method, comprising:
 contacting an anode with an anode electrolyte in an electrochemical cell wherein the anode electrolyte comprises saltwater and metal ions;   contacting a cathode with a cathode electrolyte in the electrochemical cell;   applying a voltage at the anode and the cathode and oxidizing the metal ions from a lower oxidation state to a higher oxidation state at the anode; and   reacting propylene or propane with the anode electrolyte comprising the metal ions in the higher oxidation state to form propylene oxide.   
     
     
         30 . The method of  claim 29 , wherein the anode electrolyte comprises more than 5 wt % water. 
     
     
         31 . The method of  claim 29 , wherein the reacting step is in an aqueous medium comprising more than 5 wt % water. 
     
     
         32 . The method of  claim 31 , wherein yield of the propylene oxide is more than 80% by weight. 
     
     
         33 . The method of  claim 29 , wherein the anode electrolyte comprises alkali metal ions. 
     
     
         34 . The method of  claim 33 , wherein the alkali metal ions are in an amount between 0.01-5M in the anode electrolyte. 
     
     
         35 . The method of  claim 29 , wherein the anode electrolyte comprises alkaline earth metal ions. 
     
     
         36 . The method of  claim 35 , wherein the alkaline earth metal ions are in an amount between 0.01-5M in the anode electrolyte. 
     
     
         37 . The method of  claim 29 , wherein total amount of the metal ions in the anode electrolyte is between 6-12M. 
     
     
         38 . The method of  claim 29 , wherein the anode electrolyte comprises the metal ions in the higher oxidation state in range of 4-7M, the metal ions in the lower oxidation state in range of 0.1-2M, and sodium chloride in range of 1-3M. 
     
     
         39 . The method of  claim 29 , wherein the metal ion is a metal halide and further comprising reacting the propylene or propane with the anode electrolyte comprising the metal halide in the higher oxidation state to form propylene oxide and the metal ions in the lower oxidation state. 
     
     
         40 . The method of  claim 29 , wherein the cathode is an oxygen depolarizing cathode that reduces oxygen and water to hydroxide ions; the cathode is a hydrogen gas producing cathode that reduces water to hydrogen gas and hydroxide ions; the cathode is a hydrogen gas producing cathode that reduces hydrochloric acid to hydrogen gas; or the cathode is an oxygen depolarizing cathode that reacts hydrochloric acid and oxygen gas to form water. 
     
     
         41 . The method of  claim 29 , wherein the cathode is oxygen depolarized cathode (ODC). 
     
     
         42 . The method of  claim 29 , wherein the metal ion 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. 
     
     
         43 . The method of  claim 29 , wherein the metal ion is selected from the group consisting of iron, chromium, copper, and tin. 
     
     
         44 . The method of  claim 29 , wherein the metal ion is copper. 
     
     
         45 . The method of  claim 29 , wherein the metal ion is selected from the group consisting of copper that is converted from Cu +  to Cu 2+ , iron that is converted from Fe 2+  to Fe 3− , tin that is converted from Sn 2+  to Sn 4+ , chromium that is converted from Cr 2+  to Cr 3− , and platinum that is converted from Pt 2+  to Pe  4+ . 
     
     
         46 . A method, comprising:
 contacting an anode with an anode electrolyte in an electrochemical cell wherein the anode electrolyte comprises saltwater and copper ions;   contacting a cathode with a cathode electrolyte in the electrochemical cell;   applying a voltage at the anode and the cathode and oxidizing the copper ions from a lower oxidation state to a higher oxidation state at the anode; and   reacting propylene or propane with the anode electrolyte comprising the copper ions in the higher oxidation state to form propylene oxide.   
     
     
         47 . The method of  claim 46 , wherein the anode electrolyte comprises more than 5 wt % water. 
     
     
         48 . A system, comprising:
 an anode chamber comprising an anode in contact with an anode electrolyte comprising metal ions wherein the anode is configured to oxidize the metal ions from a lower oxidation state to a higher oxidation state;   a cathode chamber comprising a cathode in contact with a cathode electrolyte;   a power source configured to apply a voltage at the anode and the cathode; and   a reactor operably connected to the anode chamber configured to react propylene or propane with the anode electrolyte comprising the metal ions in the higher oxidation state to form propylene oxide.