Processes for the conversion of mixed oxygenates feedstocks to hydrocarbon fuels
A method for forming a desired hydrocarbon fuel product from a mixed oxygenate feedstock by utilizing chemical processes to form ketones from the oxygenate feed, upgrade the ketones, recycle selected upgraded ketones through the upgrading process to obtain a desired intermediate and hydrogenating the desired intermediate to obtain the desired hydrocarbon fuel product. In various alternative configurations and embodiments this can be accomplished in a number of ways, and originate in a number of different positions and occasions.
1. A method for forming a desired hydrocarbon fuel product from a mixed oxygenate feed comprising the steps of:
forming ketones from the mixed oxygenate feedstock by passing the mixed oxygenate feedstock over a preselected catalyst under preselected conditions;
upgrading the ketones by reacting the ketones under preselected conditions;
recycling selected upgraded ketones through the upgrading process to obtain a branched cyclohexenone product; and
hydrogenating the branched cyclohexenone product to obtain the desired hydrocarbon fuel product.
2. The method of claim 1 wherein the mixed oxygenate feedstock includes alcohols, aldehydes, esters, and carboxylic acids.
3. The method of claim 1 wherein the ketones are C 2n-1 ketones.
4. The method of claim 1 wherein the forming of ketones includes passing the mixed oxygenate feedstock over a catalyst selected from the group consisting of 0.1% Pd—ZnO—ZrO 2 and 0.5% Pd—ZnO.
5. The method of claim 1 wherein the step of upgrading ketones includes passing the feedstock over a catalyst selected from the group consisting of 0.1% Pd—ZnO—ZrO 2 and 0.5% Pd—ZnO.
6. The method of claim 4 wherein the feedstock is passed at a weight hourly space velocity between 0.69 to 0.15 hr −1 .
7. The method of claim 4 wherein the reaction temperature at which the feedstock is passed over the catalyst is between 340° C. to 370° C.
8. The method of claim 1 wherein hydrogen gas generated in-situ through the formation of acetone is used in the hydrogenation step.
9. The method of claim 1 wherein the upgrading step includes dimerization over a catalyst selected from the group consisting of MgO—Al 2 O 3 and 0.01% to 1% Pd—MgO—Al 2 O 3 .
10. The method of claim 9 wherein the dimerization is performed by condensation chemistry.
11. The method of claim 1 wherein the upgrading steps includes aromatization using an acid catalyst.
12. The method of claim 1 wherein the upgrading step includes trimerization of smaller ketones over a catalyst selected from the group consisting of MgO—Al 2 O 3 and 0.01% to 1% Pd—MgO—Al 2 O 3 .
13. The method of claim 1 further comprising the step of performing a hydrodeoxygenation process to form alkanes, isoalkanes and cycloalkanes.
14. The method of claim 13 wherein the hydrodeoxygenation process includes passing C 9-15 cyclic and linear ketone mixtures over MgO—Al 2 O 3 , using a nickel-based hydrogenation catalyst.