PROCESS FOR CONVERTING HYDROCARBON FEEDSTOCKS WITH ELECTROLYTIC AND PHOTOELECTROCATALYTIC RECOVERY OF HALOGENS
A method for converting a hydrocarbon feedstock into higher hydrocarbons is provided comprising reacting a hydrocarbon feedstock with a molecular halogen to form alkyl halides; reacting at least a portion of the alkyl halide in the presence of a catalyst to form higher hydrocarbons and a hydrogen halide; and converting at least a portion of the hydrogen halide into the molecular halogen via photoelectrocatalysis. Additional methods are also provided.
1 . A method for converting a hydrocarbon feedstock into methanol, comprising:
(a) reacting a hydrocarbon feedstock with molecular halogen so as to form alkyl halides;
(b) contacting at least a portion of the alkyl halides with an alkali so as to form methanol and a halide salt; and
(c) photoelectrocatalytically converting at least a portion of the halide salt into molecular halogen.
2 . The method of claim 1 wherein the hydrocarbon feedstock comprises natural gas.
3 . The method of claim 1 wherein the hydrocarbon feedstock comprises methane.
4 . The method of claim 1 further comprising repeating steps (a) through (c), wherein the molecular halogen in step (c) is used in repeated step (a).
5 . The method of claim 1 further comprising separating the methanol from the halide salt prior to step (c).
6 . The method of claim 1 wherein the halide salt is photoelectrocatalytically converted into molecular halogen by electrolyzing the halide salt in a photoelectrocatalytic cell.
7 . The method of claim 1 wherein the hydrocarbon feedstock is derived from a biomass.
8 . The method of claim 1 wherein the hydrocarbon feedstock comprises coal.
9 . The method of claim 1 wherein the halide salt is photoelectrocatalytically converted into molecular halogen in a photoelectrocatalytic cell and wherein the method further comprises feeding carbon dioxide to the photoelectrocatalytic cell and photoelectrocatalytically converting the carbon dioxide into methanol, formic acid, or a mixture thereof.
10 . The method of claim 1 wherein the halide salt is photoelectrocatalytically converted into molecular halogen in a photoelectrocatalytic cell that comprises an electrolyte, an anodic electrode, and a cathodic electrode.
11 . The method of claim 10 wherein the anodic electrode, the cathodic electrode, or both have a flat sheet-like configuration.
12 . The method of claim 10 wherein the anodic electrode, the cathodic electrode, or both have a tubular configuration.
13 . The method of claim 10 wherein the anodic electrode, the cathodic electrode, or both have a particulate configuration.