Deoxygenation process
The invention is a process for the production of a hydrocarbon product including contacting an oxygenated aromatic feedstock, in the presence of hydrogen, with a catalyst composition including: a) a metal hydrogenation catalyst and b) a solid acid catalyst which is active for the deoxygenation of oxygenated hydrocarbons. The process is useful for the conversion of pyrolysis oils and other products derived from biomass and plastics recycling etc, into fuels and chemical feedstocks.
1. A process for the production of a hydrocarbon product comprising deoxygenating at least one oxygenated aromatic compound by contacting a feedstock comprising the at least one oxygenated aromatic compound, in the presence of hydrogen, with:
a) a metal hydrogenation catalyst and
b) a solid acid catalyst which is active for the deoxygenation of oxygenated hydrocarbons, the solid acid catalyst having a pKa<5.2.
2. A process as claimed in claim 1 , wherein said metal hydrogenation catalyst is selected from the group consisting of platinum, palladium, nickel, cobalt, copper, ruthenium, rhodium and rhenium and mixtures thereof.
3. A process as claimed in claim 1 , wherein said metal hydrogenation catalyst is present in dispersed form supported on particles of a support material.
4. A process as claimed in claim 3 , wherein said support material comprises particles of said solid acid catalyst.
5. A process as claimed in claim 3 , wherein said support material comprises particles of a material selected from the group consisting of silica-alumina, silica, a transition alumina, carbon, titania, zirconia and mixtures of two or more of these materials.
6. A process as claimed in claim 1 , wherein said solid acid catalyst comprises at least one material selected from the group consisting of a zeolite, clay, acid treated metal oxide, acid treated mixed metal oxide, supported heteropoly acid, metal oxide, mixed metal oxide, alumina-silicate, silica, silico-alumino-phosphate, sulphated carbon, proton exchange membrane, acidic ion exchange resin and immobilised Lewis acid catalyst.
7. A process as claimed in claim 1 , wherein said hydrocarbon product comprises at least one cyclic aliphatic hydrocarbon.
8. A process according to claim 1 wherein a reaction temperature is in the range from 50-400° C.
9. A process according to claim 1 wherein, in a first step, the oxygenated aromatic feedstock, in the presence of hydrogen, is contacted with the metal hydrogenation catalyst and then, in a second step, the product of said first step is contacted with the solid acid catalyst which is active for the deoxygenation of hydrocarbons.
10. A process according to claim 9 , wherein said first step is carried out at a higher temperature than said second step.
11. A process according to claim 9 , wherein said second step is carried out at a temperature of 225° C. or less.
12. A process according to claim 9 , wherein said second step is carried out in the presence of hydrogen.
13. A process according to claim 12 , wherein said second step is carried out in the presence of a metal hydrogenation catalyst.
14. A process according to claim 1 , wherein said process is carried out in a single step such that said feedstock is contacted with hydrogen, and a catalyst composition comprising both:
a) the metal hydrogenation catalyst and
b) the solid acid catalyst which is active for the deoxygenation of oxygenated hydrocarbons present in the same catalyst bed.
15. A process according to claim 1 , wherein a reaction temperature in contact with the solid acid catalyst is not greater than 250° C.
16. The process of claim 1 , wherein the metal hydrogenation catalyst and the solid acid catalyst comprise a plurality of formed particles selected from the group consisting of a tablet, an extrudate, and a granule, the formed particles having a minimum dimension of at least 1 mm and a maximum dimension less than 50 mm.