Device and method of obtaining diols and other chemicals using decarboxylation
A method for converting carboxylic acids (including carboxylic acids derived from biomass) into hydrocarbons. The produced hydrocarbons will generally have at least two oxygen containing substituents (or other substituents). In one example of application, the electrolysis converts alkali salts of carboxylic acids into diols which can then be used as solvents or be dehydrated to produce dienes, which can then be used to produce elastic polymeric materials. This process allows custom synthesis of high value chemicals from renewable feed stocks such as carboxylic acids derived from biomass.
1. An electrochemical cell comprising:
an anolyte compartment comprising an anolyte consisting of at least one alkali metal salt of a carboxylic acid in a molten state;
an anode in contact with the anolyte;
a catholyte compartment comprising a quantity of catholyte;
a cathode in contact with the catholyte;
an alkali ion conductive membrane separating the anolyte and catholyte compartments; and
a voltage source electrically connected to the anode and the cathode, wherein the voltage source decarboxylates the at least one alkali metal salt of the carboxylic acid into alkyl radicals that react to form a coupled radical product.
2. The electrochemical cell of claim 1 , wherein the cation of the at least one alkali metal salt of a carboxylic acid is selected from lithium, sodium, potassium and mixtures of the same.
3. The electrochemical cell of claim 1 , wherein the carboxylic acid of the at least one alkali metal salt is selected from the group consisting of fatty acids, alkyl carboxylic acids, amino acids, aryl carboxylic acids, and di- and tri-carboxylic acids.
4. The electrochemical cell of claim 1 , wherein the alkali ion conducting membrane comprises a thickness of between about 10 and about 5000 microns.
5. The electrochemical cell of claim 4 , wherein the alkali ion conducting membrane comprises a thickness of between about 100 and about 1000 microns.
6. The electrochemical cell of claim 5 , wherein the alkali ion conducting membrane comprises a thickness of between about 200 and about 700 microns.
7. The electrochemical cell of claim 1 , wherein the alkali ion conductive membrane comprises a planar configuration.
8. The electrochemical cell of claim 1 , wherein the alkali ion conductive membrane comprises a cylindrical configuration.
9. The electrochemical cell of claim 1 , wherein the alkali ion conductive membrane is a NaSICON or LiSICON membrane.
10. The electrochemical cell of claim 9 , wherein the catholyte comprises an alkali metal hydroxide or an alkali metal alkoxide or a mixture thereof.
11. The electrochemical cell of claim 10 , wherein the catholyte further comprises a solvent.
12. The electrochemical cell of claim 11 , wherein the solvent is water or methanol.
13. The electrochemical cell of claim 3 , wherein the cation of the at least one alkali metal salt of a carboxylic acid is selected from lithium, sodium, potassium and mixtures of the same.
14. The electrochemical cell of claim 13 , wherein the alkali ion conductive membrane is a NaSICON or LiSICON membrane.
15. The electrochemical cell of claim 14 , wherein the catholyte comprises an alkali metal hydroxide or an alkali metal alkoxide or a mixture thereof.
16. The electrochemical cell of claim 15 , further comprising a solvent selected from the group consisting of water and methanol.