Porous electrode for the electrochemical reaction of organic compounds in two immiscible phases in an electrochemical flow reactor

Abstract

A method for the electrochemical reaction of an organic material, and a device in which a corresponding method is carried out including a porous electrode for the electrochemical reaction of organic compounds in two immiscible phases in an electrochemical flow reactor. A first nonpolar solvent and a first polar electrolyte or a first organic material in the form of a liquid or gas and the first polar electrolyte form a first phase boundary with one another in such a form that the first phase boundary in the electrochemical conversion is at least partly within a first electrode, preferably at an interface between a first lipophilic layer and a second hydrophilic layer.

1 . A method of electrochemical conversion of a first organic material which is soluble in or miscible with a first nonpolar solvent, the method comprising:
 introducing the first organic material into the first nonpolar solvent to produce a first organic solvent or mixture;   providing an electrolysis cell comprising a porous first electrode comprising at least one first lipophilic layer and at least one second hydrophilic layer, where the first lipophilic layer and the second hydrophilic layer are porous, and a second electrode;   introducing the first organic solution or mixture into the electrolysis cell in such a way that the first organic solution or mixture makes contact with the first lipophilic layer of the first electrode;   introducing a first polar electrolyte into the electrolysis cell in such a way that the first polar electrolyte makes contact with the second hydrophilic layer of the first electrode and the second electrode; and   electrochemically converting the first organic material at the first electrode;
 or 
   providing an electrolysis cell comprising a porous first electrode comprising at least one first lipophilic layer and at least one second hydrophilic layer, where the first lipophilic layer and the second hydrophilic layer are porous, and a second electrode;   introducing the first organic material in the form of a liquid or gas into the electrolysis cell in such a way that the first organic material makes contact with the first lipophilic layer of the first electrode;   introducing a first polar electrolyte into the electrolysis cell in such a way that the first polar electrolyte makes contact with the second hydrophilic layer of the first electrode and the second electrode; and   electrochemically converting the first organic material at the first electrode;   wherein the first nonpolar solvent and the first polar electrolyte or the first organic material in the form of a liquid or gas and the first polar electrolyte form a first phase boundary with one another in such a form that the first phase boundary in the electrochemical conversion is at least partly within the first electrode, preferably at an interface between the first lipophilic layer and the second hydrophilic layer.   
     
     
         2 . The method as claimed in  claim 1 ,
 wherein the first polar electrolyte is liquid.   
     
     
         3 . The method as claimed in  claim 1 ,
 wherein the first electrode comprises a first current collector which is not in contact with the second hydrophilic layer.   
     
     
         4 . The method as claimed in  claim 1 ,
 wherein the first lipophilic layer has zero catalytic activity in respect of the first polar electrolyte, and/or   wherein the first lipophilic layer comprises hydrophobic first particles and/or at least one first hydrophobic binder.   
     
     
         5 . The method as claimed in  claim 1 ,
 wherein the second hydrophilic layer comprises a first electrocatalyst and optionally at least one second binder, and/or   wherein the second hydrophilic layer comprises a first ion-conducting additive, and/or first hydrophilic additives.   
     
     
         6 . The method as claimed in  claim 1 ,
 wherein the second hydrophilic layer of the first electrode makes at least partial contact with a first separator.   
     
     
         7 . The method as claimed in  claim 1 ,
 wherein the second electrode comprises at least one third lipophilic layer and at least one fourth hydrophilic layer,   wherein the third lipophilic layer and the fourth hydrophilic layer are preferably porous, wherein the first polar electrolyte makes contact with the fourth hydrophilic layer of the second electrode,   further comprising introducing—a second organic material in the form of a liquid or gas, or—a second organic solution or mixture comprising a second organic material which is soluble in or miscible with a second nonpolar solvent, and a second nonpolar solvent, into the electrolysis cell in such a way that the first organic material or the second organic solution or mixture makes contact with the third lipophilic layer of the second electrode,   wherein the second organic material is electrochemically converted at the second electrode.   
     
     
         8 . The method as claimed in  claim 7 ,
 wherein the second hydrophilic layer of the first electrode and the fourth hydrophilic layer of the second electrode make at least partial contact with a first separator on opposite sides of the first separator, wherein the first polar electrolyte is at least partly present in the first separator.   
     
     
         9 . An apparatus for electrochemical conversion of a first organic material which is soluble in or miscible with a first nonpolar solvent, comprising:
 an electrolysis cell, wherein the electrolysis cell comprises a porous first electrode comprising at least one first lipophilic layer and at least one second hydrophilic layer, wherein the first lipophilic layer and the second hydrophilic layer are porous, and a second electrode;   at least one first supply device for the supply of a first solution or mixture of a first organic material which is soluble in or miscible with a first nonpolar solvent in or with a first nonpolar solvent, or for the supply of a first organic material which is soluble in or miscible with a first nonpolar solvent, which is set up to supply the first solution or mixture of the first organic material in or with the first nonpolar solvent, or to supply the first organic material, to the electrolysis cell in such a way that the first organic solution or mixture or the first organic material makes contact with the first lipophilic layer of the first electrode; and   at least one first removal device for the removal of the remaining first solution or mixture and optionally at least one first product of the electrochemical conversion of the first organic material, or of the remaining first organic material and optionally at least one first product, or of the remaining first nonpolar solvent and optionally at least one first product, or of at least one first product, which is set up to remove the remaining first solution or mixture and optionally at least the first product of the electrochemical conversion of the first organic material, or the remaining first organic material and optionally at least the first product, or the remaining first nonpolar solvent and optionally at least the first product, or at least the first product from the electrolysis cell; and   at least one second supply device for a first polar electrolyte, which is set up to supply the first polar electrolyte to the electrolysis cell in such a way that the first polar electrolyte makes contact with the second hydrophilic layer of the first electrode and the second electrode, and/or a second removal device for the first polar electrolyte and optionally at least one first product of the electrochemical conversion of the first organic material, which is set up to remove the first polar electrolyte and optionally at least one first product of the electrochemical conversion of the first organic material from the electrolysis cell.   
     
     
         10 . The apparatus as claimed in  claim 9 ,
 wherein the first electrode comprises a first current collector that is not in contact with the second hydrophilic layer.   
     
     
         11 . The apparatus as claimed in  claim 9 ,
 wherein the first lipophilic layer comprises hydrophobic first particles and/or at least one first hydrophobic binder.   
     
     
         12 . The apparatus as claimed in  claim 9 ,
 wherein the second hydrophilic layer comprises a first electrocatalyst and optionally at least one second binder, and/or   wherein the second hydrophilic layer comprises a first ion-conducting additive, and/or first hydrophilic additives.   
     
     
         13 . The apparatus as claimed in  claim 9 ,
 wherein the second hydrophilic layer of the first electrode makes at least partial contact with a first separator.   
     
     
         14 . The apparatus as claimed in  claim 9 ,
 wherein the second electrode comprises at least one third lipophilic layer and at least one fourth hydrophilic layer,   wherein the third lipophilic layer and the fourth hydrophilic layer are porous,   wherein the second hydrophilic layer and the fourth hydrophilic layer are opposite one another but not in contact with one another in the electrolysis cell,   further comprising:   at least one further supply device for the supply of a second solution or mixture of a second organic material which is soluble in or miscible with a second nonpolar solvent in or with a second nonpolar solvent, or for the supply of a second organic material which is soluble in or miscible with a second nonpolar solvent, which is set up to supply the second solution or mixture of the second organic material in or with the second nonpolar solvent, or the second organic material, to the electrolysis cell in such a way that the second organic solution or mixture or the second organic material makes contact with the third lipophilic layer of the second electrode; and   at least one further removal device for the removal of the remaining second solution or mixture and optionally at least one second product of the electrochemical conversion of the second organic material, or of the remaining second organic material and optionally at least one second product, or of the remaining second nonpolar solvent and optionally at least one second product, or of at least one second product, which is set up to remove the remaining second solution or mixture and optionally at least the second product of the electrochemical conversion of the second organic material, or the remaining second organic material and optionally at least the second product, or the remaining second nonpolar solvent and optionally at least the second product, or at least the second product from the electrolysis cell.   
     
     
         15 . The apparatus as claimed in  claim 14 ,
 wherein the second hydrophilic layer of the first electrode and the fourth hydrophilic layer of the second electrode make at least partial contact with a first separator on opposite sides of the first separator, wherein a first polar electrolyte is at least partly present in the first separator.   
     
     
         16 . The method as claimed in  claim 2 ,
 wherein the first polar electrolyte contains water and optionally at least one salt.   
     
     
         17 . The method as claimed in  claim 4 ,
 wherein the first lipophilic layer comprises hydrophobic, conductive, first particles.   
     
     
         18 . The method as claimed in  claim 5 ,
 wherein the second hydrophilic layer comprises a first ion-conducting additive comprising a cation or anion exchanger, and/or first hydrophilic additives comprising metal oxides.   
     
     
         19 . The method as claimed in  claim 8 ,
 wherein the first separator has been swollen by the first polar electrolyte.   
     
     
         20 . The apparatus as claimed in  claim 11 ,
 wherein the first lipophilic layer comprises hydrophobic, conductive, first particles.   
     
     
         21 . The apparatus as claimed in  claim 12 ,
 wherein the second hydrophilic layer comprises a first ion-conducting additive comprising a cation or anion exchanger, and/or first hydrophilic additives comprising metal oxides.   
     
     
         22 . The apparatus as claimed in  claim 15 ,
 wherein the first separator has been swollen by the first polar electrolyte.