Electrochemical reactor and process

Abstract

The electrochemical reactors disclosed herein provide novel oxidation and reduction chemistries and employ in-creased mass transport rates of materials to and from the surfaces of electrodes

1 . An electrochemical reactor for producing chemical species, said electrochemical reactor comprising a first half-cell comprising an anode electrode and an anolyte, a second half-cell comprising a cathode electrode and a catholyte, a gas distributor introduces gas adjacent to at least one of said anode electrode and/or said cathode electrode and an ion permeable separator separating said first half-cell and said second half-cell. 
     
     
         2 . The electrochemical reactor of  claim 1  wherein the chemical species produced is determined according to the composition of said anolyte, the composition of said catholyte, the composition of the gas distributed adjacent to at least one of said anode electrode and/or said cathode electrode, and the ion permeability of said ion permeable separator. 
     
     
         3 . The electrochemical reactor of  claim 2  wherein the chemical species produced is determined according to the pH of said anolyte, the pH of said catholyte, the voltage applied to said anode electrode, the electric current applied to said anode electrode, the voltage applied to said cathode electrode, and the electric current applied to said cathode electrode. 
     
     
         4 . The electrochemical reactor of  claim 1  wherein the gas feed volume flow rate to said cathode electrode and/or anode electrode is from about 100 to about 1400 times greater than the liquid anolyte or liquid catholyte flow rate. 
     
     
         5 . The electrochemical reactor of  claim 4  wherein said cathode electrode exhibits electroactivity over greater than 50% of its specific surface area, and
 wherein said cathode electrode has a specific surface area greater than about 1 m 2  per 1 m 2  superficial area, preferably a specific surface area greater than about 5 m 2  per 1 m 2  superficial area, more preferably a specific surface area greater than about 10 m 2  per 1 m 2  superficial area, and even more preferably a specific surface area greater than about 100 m 2  per 1 m 2  superficial area. 
 
     
     
         6 . The electrochemical reactor of  claim 4  wherein the composition of the gas is from about 20% oxygen to about 93% oxygen. 
     
     
         7 . The electrochemical reactor of  claim 1  wherein said chemical species produced are selected from the group consisting essentially of: hydrogen peroxide, superoxide, alkali, acids, citric acid, sodium hypochlorite, hypochlorites, sulfate acids, chlorine, and chlor-alkali. 
     
     
         8 . A method for using a flow pathway in the electrochemical reactor of  claim 5  to produce at least one product chemical species, said flow pathway comprising:
 introducing said liquid anolyte into said first half-cell wherein at least one chemical species of said liquid anolyte is oxidized at said anode electrode, and 
 introducing said liquid catholyte into said second half-cell wherein said gas distributor introduces said gas into said liquid catholyte and creates a multiphase catholyte solution, and 
 wherein said gas distributor introduces said gas into said cathode electrode, and 
 wherein at least one chemical species of said multiphase catholyte solution is reduced at said cathode electrode, and 
 wherein the reduced multiphase catholyte solution and/or the oxidized liquid anolyte contains said at least one product chemical species, and 
 wherein the reduced multiphase catholyte solution flows out of said second half-cell, and 
 wherein the oxidized liquid anolyte flows out of said first half-cell. 
 
     
     
         9 . The method of  claim 8  wherein said at least one product chemical species is selected from the woup consisting essentially of: hydrogen peroxide, superoxide, alkali, acids, citric acid, sodium hypochlorite, hypochlorites, sulfate acids, chlorine, and chlor-alkali. 
     
     
         10 . An electrochemical reactor for reducing and/or oxidizing chemical species, said electrochemical reactor comprising a first half-cell comprising an anode electrode and an anolyte, a second half-cell comprising a cathode electrode and a catholyte, a gas distributor introduces gas adjacent to at least one of said anode electrode and/or said cathode electrode and an ion permeable separator separating said first half-cell and said second half-cell. 
     
     
         11 . The electrochemical reactor of  claim 10  wherein the chemical species reduced and/or oxidized is determined according to the composition of said anolyte, the composition of said catholyte, the composition of the gas distributed adjacent to at least one of said anode electrode and/or said cathode electrode, and the ion permeability of said ion permeable separator. 
     
     
         12 . The electrochemical reactor of  claim 11  wherein the chemical species reduced and/or oxidized is determined according to the pH of said anolyte, the pH of said catholyte, the voltage applied to said anode electrode, the electric current applied to said anode electrode, the voltage applied to said cathode electrode, and the electric current applied to said cathode electrode. 
     
     
         13 . The electrochemical reactor of  claim 10  wherein the gas feed volume flow rate to said cathode electrode and/or anode electrode is from about 100 to about 1400 times greater than the liquid anolyte or liquid catholyte flow rats. 
     
     
         14 . The electrochemical reactor of  claim 13  wherein said cathode electrode exhibits electroactivity over greater than 50% of its specific surface area, and
 wherein said cathode electrode has a specific surface area greater than about 1 m 2  per 1 m 2  superficial area, preferably a specific surface area greater than about 5 m 2  per 1 m 2  superficial area, more preferably a specific surface area greater than about 10 m 2  per 1 m 2  superficial area, and even more preferably a specific surface area greater than about 100 m 2  per 1 m 2  superficial area. 
 
     
     
         15 . The electrochemical reactor of  claim 13  wherein the composition of the gas is from about 20% oxygen to about 93% oxygen. 
     
     
         16 . The electrochemical reactor of  claim 10  wherein said chemical species reduced and/or oxidized are selected from the group consisting essentially of: molecular oxygen, hydroxyl radicals, hydroxide ions, hydrogen ions, hydrogen peroxide, superoxide, oxygen, water, alkali, acids, citric acid, sodium hypochlorite, hypochlorites, sulfate acids, hypochlorous acid, chlorine, and chlor-alkali 
     
     
         17 . A method for using a flow pathway in the electrochemical reactor of  claim 14  to reduce and/or oxidize at least one chemical species, said flow pathway comprising:
 introducing said liquid anolyte into said first half-cell wherein at least one chemical specics of said liquid anolytc is oxidized at said anode electrode, and introducing said liquid catholyte into said second half-cell wherein said gas distributor introduces said gas into said liquid catholyte and creates a multiphase catholyte solution, and 
 wherein said gas distributor introduces said gas into said cathode electrode, and 
 wherein at least one chemical species of said multiphase catholyte solution is reduced at said cathode electrode, and 
 wherein the reduced multiphase catholyte solution and/or the oxidized liquid anolyte contains said at least one chemical species that has been reduced and/or oxidized, and 
 wherein the reduced multiphase catholyte solution flows out of said second half-cell, and 
 wherein the oxidized liquid anolyte flows out of said first half-cell. 
 
     
     
         18 . The method of  claim 17  wherein said at least one chemical species that has been reduced and/or oxidized are selected from the group consisting essentially of: molecular oxygen, hydroxyl radicals, hydroxide ions, hydrogen ions, hydrogen peroxide, superoxide, oxygen, water, alkali, acids, citric acid, sodium hypochlorite, hypochlorites, sulfate acids, hypochlorous acid, chlorine, and chlor-alkali. 
     
     
         19 . An electrochemical reactor, said electrochemical reactor comprising:
 a containment boundary, a gas chamber, a gas distributor, a cathode chamber, a three dimensional cathode, a separator, an anode chamber, a three dimensional anode, and   wherein said containment boundary contains said gas chamber, said gas distributor, said cathode chamber, said three dimensional cathode, said separator, said anode chamber, said three dimensional anode, and   wherein said gas chamber is defined on a first side by said containment boundary and on a second side by a first side of said gas distributor, and   wherein a second side of said gas distributor is in contact with and defines a first side of said cathode chamber, and   wherein said cathode chamber is further defined on a second side by a first side of said separator, and   wherein said cathode chamber contains said three dimensional cathode, and   wherein said anode chamber is in contact with and defined on a first side by a second side of said separator, and   wherein said anode chamber is further defined on a second side by said containment boundary, and   wherein said anode chamber contains a three dimensional anode.   
     
     
         20 . The electrochemical reactor of  claim 19  wherein the superficial area of said second side of said gas distributor is equal to or greater than the superficial area of a side of said three dimensional cathode that faces said second side of said gas distributor, and
 wherein said superficial area of said second side of said gas distributor is separate from said three dimensional cathode. 
 
     
     
         21 . A method for using a flow pathway in the electrochemical reactor of  claim 20  to produce at least one chemical species, said flow pathway comprising:
 introducing an anolyte flow into said anode chamber wherein at least one chemical species of said anolyte flow is oxidized at said three dimensional anode, and 
 introducing a catholyte flow into said cathode chamber wherein said gas distributor introduces a gas into said catholyte flow and creates a multiphase catholyte solution, and 
 wherein said gas distributor introduces said gas into said three dimensional cathode, and 
 wherein at least one chemical species of said multiphase catholyte solution is reduced at said three dimensional cathode, and 
 wherein the reduced multiphase catholyte solution flows out of said cathode chamber, and 
 wherein the oxidized anolyte flow flows out of said anode chamber, and 
 wherein the reduced multiphase catholyte solution and/or the oxidized anode flow contains said at least one chemical species produced. 
 
     
     
         22 . The method of  claim 21  wherein said at least one chemical species produced is selected from the group consisting essentially of: hydrogen peroxide, superoxide, alkali, acids, citric acid, sodium hypochlorite, hypochlorites, sulfate acids, chlorine, and chlor-alkali. 
     
     
         23 . A tubular electrochemical reactor, said tubular electrochemical reactor comprising:
 a tubular gas chamber, a tubular gas dispersion tube, a cathode flow channel, a tubular cathode, a tubular separator, a tubular anode, a tubular anolyte chamber, a tubular anolyte chamber housing, and   wherein said tubular gas chamber resides within and i s defined by the interior surface of said tubular gas dispersion tube, and   wherein the exterior surface of said tubular gas dispersion tube forms the interior side of said cathode flow channel, and   wherein the interior surface of said tubular separator forms the exterior side of said cathode flow channel, and   wherein said tubular cathode resides within said cathode flow channel, and   wherein the exterior surface of said tubular separator forms the interior side of said tubular anolyte chamber, and   wherein the exterior side of said tubular anolyte chamber is formed by the interior surface of said tubular anolyte chamber housing, and   wherein said tubular anode resides within said tubular anolyte chamber.   
     
     
         24 . The tubular electrochemical reactor of  claim 23  further comprising a first toroidal seat plate, a second toroidal seat plate, a first end plate, a second end plate, a first toroidal cathode current distributor and compression ferrule, a second toroidal cathode current distributor and compression ferrule, and
 wherein a second side of said first toroidal seat plate forms a first end of said tubular anolyte chamber by bridging a first end of said interior surface of said tubular anolyte chamber housing at an exterior portion of said first toroidal seat plate and a first end of said exterior surface of said tubular separator at an interior portion of said first toroidal seat plate, and 
 wherein a first side of said second toroidal seat plate forms a second end of said tubular anolyte chamber by bridging a second end of said interior surface of said tubular anolyte chamber housing at an exterior portion of said second toroidal seat plate and a second end of said exterior surface of said tubular separator at an interior portion of said second toroidal seat plate, and 
 wherein a second side of said first toroidal cathode current distributor and compression ferrule contacts a first end of said tubular cathode, and 
 wherein said second side of said first toroidal cathode current distributor and compression ferrule bridges a first end of said tubular separator and a interior surface of said first toroidal seat plate, and 
 wherein a first side of said second toroidal cathode current distributor and compression ferrule contacts a second end of said tubular cathode, and 
 wherein said first side of said second toroidal cathode current distributor and compression ferrule bridges a second end of said tubular separator and a interior surface of said second toroidal seat plate, and 
 wherein a second side of said first cnd plate forms a first end of said tubular gas chamber, and 
 wherein said second side of said first end plate forms a first end of said tubular gas dispersion tube, and 
 wherein said second side of said first end plate compresses said first toroidal cathode current distributor and compression ferrule between said second side of said first end plate and said first side of said first toroidal seat plate, and 
 wherein a first side of said second end plate forms a second end of said tubular gas chamber, and 
 wherein said first side of said second end plate forms a second end of said tubular gas dispersion tube, and 
 wherein said first side of said second end plate compresses said second toroidal cathode current distributor and compression ferrule between said first side of said second end plate and a second side of said second toroidal seat plate. 
 
     
     
         25 . The tubular electrochemical reactor of  claim 24  further comprising at least one cathode electrical feed through post in said first and said second end plate, at least one catholyte intlet/outlet port in said first and said second end plate, at least one gas inlet/outlet port in said first and said second end plate, at least one anolyte inlet/outlet port in said tubular anolyte chamber housing, at least one anode electrical feed through post that passes through said tubular anolyte chamber housing and makes contact with said tubular anode at at least one anode current collector tab. 
     
     
         26 . The tubular electrochemical reactor of  claim 25  wherein a second end of said at least one cathode electrical feed through post contacts a first toroidal cathode current distributor and compression ferrule, and
 wherein a first end of said at least one cathode electrical feed through post protrudes from a first side of said first end plate, and 
 wherein a first end of said at least one cathode electrical feed through post contacts a second toroidal cathode current distributor and compression ferrule, and 
 wherein a second end of said at least one cathode electrical feed through post protrudes from a second side of said second end plate. 
 
     
     
         27 . The tubular electrochemical reactor of  claim 26  wherein at least one catholyte intlet/outlet port in said first and said second end plate forms a channel with said cathode flow channel, and
 wherein at least one gas inlet/outlet port in said first and said second end plate forms a channel with said tubular gas chamber, and 
 wherein at least one anolyte inlet/outlet port in said tubular anolyte chamber housing forms a channel with said tubular anolyte chamber. 
 
     
     
         28 . A method for using a flow pathway in the tubular electrochemical reactor of  claim 27  to produce at least one chemical species, said flow pathway comprising:
 introducing an anolyte flow into said tubular anolyte chamber wherein at least one chemical species of said anolyte flow is oxidized at said tubular anode, and 
 introducing a catholyte flow into said cathode chamber wherein said tubular gas distributor introduces a gas into said catholyte flow and creates a multiphase catholyte solution, and 
 wherein said tubular gas distributor introduces said gas into said tubular cathode, and 
 wherein at least one chemical species of said multiphase catholyte solution is reduced at said tubular cathode, and 
 wherein the reduced multiphase catholyte solution and/or the oxidized anode flow contains said at least one chemical species produced, and 
 wherein the reduced multiphase catholyte solution flows out of said cathode chamber, and 
 wherein the oxidized anolyte flow flows out of said tubular anolyte chamber. 
 
     
     
         29 . The method of  claim 28  wherein said at least one chemical species produced is selected from the group consisting essentially of: hydrogen peroxide, superoxide, alkali, acids, citric acid, sodium hypochlorite, hypochlorites, sulfate acids, chlorine, and chlor-alkali. 
     
     
         30 . The tubular electrochemical reactor of  claim 27  wherein said tubular separator is selectively permeable to cations. 
     
     
         31 . The tubular electrochemical reactor of  claim 27  wherein said tubular separator is selectively permeable to anions. 
     
     
         32 . The tubular electrochemical reactor of  claim 27  wherein said tubular cathode has a thickness that is between about 0.1 and 10 millimeters, and preferably between about 0.5 and 5 millimeters and more preferably between about 1 and 3 millimeters. 
     
     
         33 . The tubular electrochemical reactor of  claim 27  wherein said tubular cathode exhibits electroactivity over greater than 50% of its specific surface area, and
 wherein said tubular cathode has a specific surface area greater than about 1 m 2  per 1 m 2  superficial area, preferably a specific surface area greater than about 5 m 2  per 1 m 2  superficial area, more preferably a specific surface area greater than about 10 m 2  per 1 m 2  superficial area, and even more preferably a specific surface area greater than about 100 m 2  per 1 m 2  superficial area. 
 
     
     
         34 . A method of making hydrogen peroxide by providing the electrochemical reactor of  claim 27  with a catholyte feed, an anolyte feed, a gas feed, a voltage to said tubular cathode, and a voltage to said tubular anode. 
     
     
         35 . A method of making superoxide by providing the electrochemical reactor of  claim 27  with a catholyte feed, an anolyte feed, a gas feed, a voltage to said tubular cathode, and a voltage to said tubular anode. 
     
     
         36 . A method of making a mixture of hydrogen peroxide and superoxide in said cathode flow channel of the electrochemical reactor of  claim 27  by providing a catholyte feed, an anolyte feed, a gas feed, a voltage to said tubular cathode, and a voltage to said tubular anode of said electrochemical reactor. 
     
     
         37 . A method of making alkaline hydrogen peroxide and citric acid by providing the electrochemical reactor of  claim 27  with a catholyte feed, an anolyte feed, a gas feed, a voltage to said tubular cathode, and a voltage to said tubular anode. 
     
     
         38 . A method of making alkaline hydrogen peroxide and sulfate acids by providing the electrochemical reactor of  claim 27  with a catholyte feed, an anolyte feed, a gas feed, a voltage to said tubular cathode, and a voltage to said tubular anode. 
     
     
         39 . A method of making alkaline hydrogen peroxide and sodium hypochlorite by providing the electrochemical reactor of  claim 27  with a catholyte feed, an anolyte feed, a gas feed, a voltage to said tubular cathode, and a voltage to said tubular anode.