Electrochemical, halogenation, and oxyhalogenation systems and methods

Abstract

Disclosed herein are methods and systems that relate to electrochemically oxidizing metal halide with a metal ion in a lower oxidation state to a higher oxidation state; halogenating an unsaturated hydrocarbon or a saturated hydrocarbon with the metal halide with the metal ion in the higher oxidation state; and oxyhalogenating the metal halide with the metal ion from a lower oxidation state to a higher oxidation state in presence of an oxidant. In some embodiments, the oxyhalogenation is in series with the electrochemical oxidation, the electrochemical oxidation is in series with the oxyhalogenation, the oxyhalogenation is parallel to the electrochemical oxidation, and/or the oxyhalogenation is simultaneous with the halogenation.

1 - 25 . (canceled) 
     
     
         26 . A method, comprising:
 (i) contacting an anode with an anode electrolyte wherein the anode electrolyte comprises metal halide and saltwater; contacting a cathode with a cathode electrolyte; applying a voltage to the anode and the cathode and oxidizing the metal halide with metal ion in a lower oxidation state to a higher oxidation state at the anode;   (ii) halogenating an unsaturated hydrocarbon or a saturated hydrocarbon with the metal halide with the metal ion in the higher oxidation state in the saltwater to result in one or more organic compounds or enantiomers thereof and the metal halide with the metal ion in the lower oxidation state; and   (iii) oxyhalogenating the metal halide with the metal ion in the lower oxidation state to the higher oxidation state in presence of an oxidant and the saltwater;   wherein the step (iii) is parallel to the step (i).   
     
     
         27 . The method of  claim 26 , wherein the method comprises delivering both the anode electrolyte of the step (i) comprising the metal halide with the metal ion in the higher oxidation state as well as saltwater of the oxyhalogenating step (iii) comprising the metal halide with the metal ion in the higher oxidation state to the halogenating step (ii). 
     
     
         28 . The method of  claim 27 , wherein the metal halide with the metal ion in the lower oxidation state from the step (ii) is re-circulated back to the anode electrolyte of the step (i) and/or is re-circulated back to the oxyhalogenating step (iii). 
     
     
         29 . The method of  claim 26 , further comprising separating the one or more organic compounds or enantiomers thereof from the metal halide with the metal ion in the lower oxidation state in the saltwater after the halogenating step (ii) and delivering the metal halide with the metal ion in the lower oxidation state to the anode electrolyte of the step (i) and/or to the oxyhalogenating step (iii). 
     
     
         30 . The method of  claim 26 , wherein the cathode electrolyte comprises water and the cathode is an oxygen depolarizing cathode that reduces oxygen and water to hydroxide ions; the cathode electrolyte comprises water and the cathode is a hydrogen gas producing cathode that reduces water to hydrogen gas and hydroxide ions; the cathode electrolyte comprises hydrochloric acid and the cathode is a hydrogen gas producing cathode that reduces hydrochloric acid to hydrogen gas; or the cathode electrolyte comprises hydrochloric acid and the cathode is an oxygen depolarizing cathode that reacts hydrochloric acid and oxygen gas to form water. 
     
     
         31 . The method of  claim 26 , wherein the oxidizing, the halogenating and the oxyhalogenating steps are carried out in the saltwater. 
     
     
         32 . The method of  claim 26 , wherein the saltwater comprises alkali metal halide. 
     
     
         33 . The method of  claim 32 , wherein the alkali metal halide is sodium chloride, sodium bromide, sodium fluoride, sodium iodide, potassium chloride, potassium bromide, potassium fluoride, potassium iodide, lithium chloride, lithium bromide, lithium fluoride, or lithium iodide. 
     
     
         34 . The method of  claim 26 , wherein metal ion in the metal halide 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. 
     
     
         35 . The method of  claim 26 , wherein metal ion in the metal halide is selected from the group consisting of iron, chromium, copper, and tin. 
     
     
         36 . The method of  claim 26 , wherein metal ion in the metal halide is selected from 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+ , platinum that is converted from Pt 2+  to Pt 4+ , or combinations thereof. 
     
     
         37 . The method of  claim 26 , wherein the unsaturated hydrocarbon is ethylene, propylene, or butylene which reacts with the metal halide with the metal ion in the higher oxidation state wherein the halide is chloride, bromide, fluoride, or iodide. 
     
     
         38 . The method of  claim 26 , wherein the unsaturated hydrocarbon is a C2-C10 alkene or the saturated hydrocarbon is C2-C10 alkane. 
     
     
         39 . The method of  claim 26 , wherein the saturated hydrocarbon is methane, ethane, or propane. 
     
     
         40 . The method of  claim 26 , wherein the oxidant is X 2  gas alone; or HX gas and/or HX solution in combination with gas comprising oxygen or ozone; hydrogen peroxide; HXO or salt thereof, HXO 3  or salt thereof; HXO 4  or salt thereof, or combinations thereof, wherein each X independently is a halogen selected from fluoro, chloro, iodo, and bromo. 
     
     
         41 . The method of  claim 40 , wherein the HX is HCl and the oxyhalogenation is oxychlorination; HX is HBr and the oxyhalogenation is oxybromination; or HX is HF and the oxyhalogenation is oxyfluorination. 
     
     
         42 . The method of  claim 26 , wherein concentration of the metal halide with the metal ion in the lower oxidation state exiting the electrochemical reaction and entering the halogenation reaction is between about 0.5-2M; concentration of the metal halide with the metal ion in the lower oxidation state exiting the oxyhalogenation reaction and entering the halogenation reaction is between about 0.5-2.5M; concentration of the metal halide with the metal ion in the lower oxidation state exiting the halogenation reaction and entering the oxyhalogenation reaction and/or entering the electrochemical reaction is between about 0.6-2.5M; or combinations thereof. 
     
     
         43 . The method of  claim 26 , wherein the yield of the one or more organic compounds is more than 90 wt % and/or the space time yield (STY) of the one or more organic compounds is more than 0.5. 
     
     
         44 . A system, comprising:
 an electrochemical cell comprising an anode in contact with an anode electrolyte wherein the anode electrolyte comprises metal halide and saltwater; a cathode in contact with a cathode electrolyte; and a voltage source configured to apply a voltage to the anode and the cathode wherein the anode is configured to oxidize the metal halide with the metal ion from a lower oxidation state to a higher oxidation state;   a halogenation reactor operably connected to the electrochemical cell and an oxyhalogenation reactor wherein the halogenation reactor is configured to receive the anode electrolyte comprising the metal halide with the metal ion in the higher oxidation state from the electrochemical cell and/or configured to receive the metal halide solution with the metal ion in the higher oxidation state from the oxyhalogenation reactor and halogenate an unsaturated hydrocarbon or a saturated hydrocarbon with the metal halide with the metal ion in the higher oxidation state to result in one or more organic compounds or enantiomers thereof and the metal halide solution with the metal ion in the lower oxidation state; and   the oxyhalogenation reactor operably connected to the electrochemical cell and/or the halogenation reactor and configured to oxyhalogenate the metal halide with the metal ion from the lower oxidation state to the higher oxidation state in presence of an oxidant,   wherein the oxyhalogenation reactor is parallel to the electrochemical cell.   
     
     
         45 . The system of  claim 44 , wherein the electrochemical cell, the halogenation reactor and the oxyhalogenation reactor are all configured to carry out the reactions in saltwater.