Renewable jet production
View Patent ↗Systems and methods are provided for production of renewable jet fuel and/or jet fuel blending component fractions. The systems and methods provide for formation of jet boiling range fractions via hydrodeoxygenation and catalytic dewaxing of bio-derived feeds. The systems and methods for reducing or minimizing recycle and/or forming only a jet boiling range product and a lower boiling range product can be facilitated based on selection of a suitable feedstock and/or based on selection of suitable reaction conditions and catalyst for the catalytic dewaxing.
1. A method for producing a renewable jet boiling range fraction, comprising:
contacting a bio-derived feedstock with a hydrotreatment catalyst under effective hydrotreatment conditions to produce a deoxygenated effluent comprising a deoxygenated liquid fraction, the bio-derived feedstock comprising 70 wt % or more of C 17+ carbon chains;
contacting at least a portion of the deoxygenated liquid fraction with a dewaxing catalyst comprising ZSM-48 and Pt, Pd, or a combination thereof under effective dewaxing conditions to produce an isomerized effluent, the effective dewaxing conditions comprising a severity index of 3 to 9, a weighted average bed temperature of 300° C. to 350° C., a pressure of 1.4 MPa-g to 14 MPa-g, and a LHSV of 1.0 hr −1 to 8.0 hr −1 relative to a volume of dewaxing catalyst; and
separating the isomerized effluent to form a jet boiling range fraction as a bottoms fraction and one or more lower boiling fractions, the jet boiling range fraction comprising a T90 distillation point of 300° C. or less, a freeze point of −40° C. or less, 40 wt % or more of C 17 -C 18 hydrocarbons and 45 wt % or less of C 14 -C 17 hydrocarbons, and a flash point of 38° C. or more.
2. The method of claim 1 , wherein a yield of the jet boiling range fraction is 70 wt % or more relative to a weight of the at least a portion of the deoxygenated liquid fraction.
3. The method of claim 1 , wherein the jet boiling range fraction comprises 1.0 wppm or less of oxygen.
4. The method of claim 1 , wherein the jet boiling range fraction comprises a final boiling point of 300° C. or less.
5. The method of claim 1 , wherein the bio-derived feedstock comprises 5.0 wt % or less of C 19+ carbon chains.
6. The method of claim 1 , wherein the at least a portion of the deoxygenated effluent comprises 50 wt % or more of C 17+ n-paraffins.
7. The method of claim 1 , wherein contacting the bio-derived feedstock with a hydrotreatment catalyst further comprises contacting at least a portion of the deoxygenated effluent with the hydrotreatment catalyst.
8. The method of claim 1 , wherein the at least a portion of the deoxygenated liquid fraction is exposed to the dewaxing catalyst without exposing a liquid portion of the isomerized effluent to the dewaxing catalyst.
9. The method of claim 1 , wherein exposing the at least a portion of the deoxygenated liquid fraction to the dewaxing catalyst further comprises exposing at least a portion of the jet boiling range fraction to the dewaxing catalyst.
10. The method of claim 1 , wherein a density of the jet boiling range fraction is 765 kg/m 3 to 772 kg/m 3 .
11. The method of claim 1 , wherein the dewaxing catalyst comprises 0.1 wt % to 2.0 wt % of Pt, Pd, or a combination thereof, relative to a weight of the dewaxing catalyst.
12. The method of claim 1 , wherein the dewaxing catalyst further comprises a binder.
13. The method of claim 1 , further comprising separating the deoxygenated liquid fraction from the deoxygenated effluent.
14. A method for producing a renewable jet boiling range fraction, comprising:
contacting a bio-derived feedstock with a hydrotreatment catalyst under effective hydrotreatment conditions to produce a deoxygenated effluent comprising a deoxygenated liquid fraction, the bio-derived feedstock comprising 70 wt % or more of C 17+ carbon chains;
contacting at least a portion of the deoxygenated liquid fraction with a dewaxing catalyst comprising ZSM-48 and Pt, Pd, or a combination thereof under effective dewaxing conditions to produce an isomerized effluent, the effective dewaxing conditions comprising a severity index of 3 to 9, a weighted average bed temperature of 300° C. to 350° C., a pressure of 1.4 MPa-g to 14 MPa-g, and a LHSV of 1.0 hr −1 to 8.0 hr −1 relative to a volume of dewaxing catalyst; and
separating the isomerized effluent to form a jet boiling range fraction and one or more additional fractions, the jet boiling range fraction comprising a T90 distillation point of 300° C. or less, a freeze point of −40° C. or less, 40 wt % or more of C 17 -C 18 hydrocarbons and 45 wt % or less of C 14 -C 17 hydrocarbons, and a flash point of 38° C. or more.
15. The method of claim 14 , wherein a yield of the jet boiling range fraction is 70 wt % or more relative to a weight of the at least a portion of the deoxygenated liquid fraction.
16. The method of claim 14 , wherein the jet boiling range fraction comprises 1.0 wppm or less of oxygen.
17. The method of claim 14 , wherein the jet boiling range fraction comprises a final boiling point of 300° C. or less.
18. The method of claim 14 , wherein the bio-derived feedstock comprises 5.0 wt % or less of C 19+ carbon chains.
19. The method of claim 14 , wherein the at least a portion of the deoxygenated effluent comprises 50 wt % or more of C 17+ n-paraffins.