Method for producing ketones for fuel and oil applications

1. A method for producing ketones, suitable for manufacture of base oil or diesel fuel components, from a feedstock of biological origin containing fatty acids or fatty acid derivatives, wherein the feedstock is at least partly in liquid phase, the method comprising:

introducing the feedstock into a ketonisation reactor together with a carrier gas stream containing CO 2 ;

subjecting the feedstock to a catalytic ketonisation reaction, wherein the ketonisation reaction is carried out in a system having one or more ketonisation reactor(s) each with at least one ketonisation catalyst bed;

separating gas containing CO 2 from an effluent exiting a ketonisation reactor whereby the effluent containing ketones is used either as a feedstock for a further ketonisation reactor or for recovery of ketones from the effluent; and

recycling the separated gas containing CO 2 for use in the carrier gas stream in a ketonisation reactor.

2. Method according to claim 1 , wherein the feedstock is at least 60 wt-% in liquid phase.

3. Method according to claim 1 , wherein the feedstock of biological origin comprises:

at least one of saturated free fatty acids, saturated fatty acid esters, esters, amides, aldehydes, alcohols, anhydrides, metal salts, or mixture thereof, or fatty acid glycerols.

4. Method according to claim 1 , wherein the feedstock of biological origin comprises:

at least one of saturated free fatty acids, saturated fatty acid esters having an average carbon chain length of from C 4 to C 24 , or saturated fatty acid esters having an average carbon chain length of from C 6 to C 24 .

5. Method according to claim 1 , wherein the catalyst bed comprises:

a ketonisation catalyst which is a metal oxide catalyst selected from a list consisting of one or more of: Ti, Mn, Mg, Ca, and Zr containing metal oxide catalyst.

6. Method according to claim 1 , wherein a temperature in the feedstock is at least 330° C.

7. Method according claim 6 , wherein the temperature is 365° C. or less.

8. Method according to claim 7 , wherein a pressure in a ketonisation reactor is as least 1000 kPa.

9. Method according to claim 1 , wherein the liquid feed flow rate, WHSV, is from 0.1 to 10 −1 .

10. A method according to claim 1 , wherein the ketonisation reaction is carried out in a system having two or more ketonisation reactors in series each with a ketonisation catalyst bed, the method comprising:

introducing the feedstock into the first ketonisation reactor together with a first carrier gas stream containing CO 2 ; and

separating the gas containing CO 2 from the effluent exiting the first ketonisation reactor whereby the effluent is introduced into the second ketonisation reactor together with a second carrier gas stream containing CO 2 ; and if the system includes more than two ketonisation reactors:

separating the gas containing CO 2 from the effluent exiting each ketonisation reactor leaving a degassed effluent which is subsequently introduced into a next ketonisation reactor together with a further carrier gas stream containing CO 2 ;

separating gas containing CO 2 from effluent exiting a final ketonisation reactor whereby the effluent containing ketones is used for recovery; and

recycling the separated gas streams containing CO 2 for use as the carrier gas stream in one or more of the ketonisation reactor(s).

11. Method according to claim 10 , wherein a pressure in each ketonisation reactor in series following the first ketonisation reactor is lower than a pressure in a preceding ketonisation reactor.

12. Method according to claim 10 , wherein a catalyst loading in the catalyst bed in each ketonisation reactor in series following the first ketonisation reactor is higher than a catalyst loading in a first ketonisation reactor by at least 10% higher in the second reactor or at least 50% higher in a third reactor.

13. Method according to claim 1 , wherein the system includes at least two ketonisation reactors.

14. Method according to claim 13 , comprising:

heating the effluent exiting a ketonisation reactor and separated from gas containing CO 2 before introduction into a subsequent ketonisation reactor.

15. Method according to claim 1 , comprising:

purifying the separated gas streams containing CO 2 before recycling; and

recovering the separated gas steams in a separation process by:

separating CO 2 and H 2 O vapour from unreacted fatty acids and volatile organic compounds or separating substantially pure CO 2 , which is at least 98% pure, from the waste water; and

optionally recycling unreacted fatty acids or fatty acid derivatives to a ketonisation reactor.

16. Method according to claim 15 , comprising:

purifying the separated gas containing CO 2 by cooling, and optionally further purification

drying recovered purified gas before recycling to a ketonisation reactor.

17. Method according to claim 15 , comprising:

recovering and compressing substantially pure CO 2 , optionally under heating, before being recycled to a ketonisation reactor.

18. Method according to claim 16 , wherein heat generated by the cooling is used for compression under heating of the substantially pure CO 2 .

19. Method according to claim 1 , comprising:

a hydrodeoxygenation, optional isomerization, and optional hydrofinishing.

20. A system for producing ketones, suitable for manufacture of base oil components, from a feedstock of biological origin containing fatty acids or fatty acid derivatives by subjecting the feedstock to a catalytic ketonisation reaction, wherein the system comprises:

one or more ketonisation reactors (A′, B′) each having a ketonisation catalyst bed (G′), means for heating, inlet means for the feedstock, and outlet means for the effluent exiting a ketonisation reactor, wherein the one or more ketonisation reactors each includes:

inlet means for carrier gas streams, and outlet means for separated gas streams containing CO 2 ; and wherein the system comprises:

one or more gas-liquid separators (D′, E′) for separating CO 2 in separated gas streams from H 2 O vapour, unreacted fatty acids or fatty acid derivatives, or volatile organic compounds, and means (F′) for recirculating and optionally compressing the separated CO 2 ; and optionally

recycling means for liquid containing unreacted fatty acids or fatty acid derivatives, and outlet means for separated CO 2 .

21. System according to claim 20 , comprising:

means for purifying separated CO 2 to a substantially pure CO 2 gas, which is at least 98% pure.

22. System according to claim 20 , comprising:

two, three or four ketonisation reactors, in series.

23. System according to claim 20 , comprising:

three ketonisation reactors (A, B, C), in series, each having a ketonisation catalyst bed (G), means for heating, inlet means for the feedstock, and outlet means for effluent exiting a ketonisation reactor; wherein the three ketonisation reactors each include:

inlet means for a carrier gas stream, and outlet means for separated gas streams containing CO 2 ; and wherein the system includes:

one or more gas-liquid separators (D, E) for separating CO 2 in separated gas streams from H 2 O vapour, unreacted fatty acids or fatty acid derivatives, or volatile organic compounds, and means (F) for recirculating and optionally compressing the separated CO 2 ; and optionally

recycling means for liquid containing unreacted fatty acids or fatty avid derivatives, and outlet means for separated CO 2 .

24. System according to claim 20 , wherein the one or more ketonisation reactors is a trickle bed reactor.

25. System according to claim 20 , comprising:

means for purification of gas containing CO 2 , including means for separating CO 2 and/H 2 O vapour from volatile organic compounds.

26. Method for supplying a gas containing CO 2 as a carrier gas stream in a ketonisation reaction, the method comprising:

producing the gas containing CO 2 in a catalytic ketonisation reaction producing ketones, suitable for manufacture of base oil components, from a feedstock of biological origin containing fatty acids or fatty acid derivatives, wherein the feedstock is at least partly in liquid phase, in one or more ketonisation reactors each having a ketonisation catalyst bed; and

separating the gas from effluent exiting a ketonisation reactor and recycling the gas.

27. Method according to claim 26 for enhancing the gas flow within a ketonisation reactor having a ketonisation catalyst bed, comprising:

subjecting a feedstock of biological origin containing fatty acids or fatty acid derivatives to a ketonisation reaction.

28. Method according to claim 26 , comprising:

purifying and recovering the separated gas containing CO 2 before recycling in a separation process by separating CO 2 from H 2 O vapour or volatile organic compounds; and

optionally separating the CO 2 as substantially pure CO 2 from the waste water.

29. Method according to claim 28 , comprising:

cooling the separated gas containing CO 2 before purification; or

drying the recovered purified gas before recycling to a ketonisation reactor.

30. Method according to claim 26 , comprising:

purifying and recovering substantially pure CO 2 , optionally under heating, before being recycled to a ketonisation reactor.

31. Method for the manufacture of base oil or base oil components, the method comprising:

producing ketones according to claim 1 ; and

manufacturing a base oil or base oil components with the ketones.

32. Method according to claim 1 , wherein the feedstock is selected to be at least one of 65 wt-%, at least 70 wt-%, at least 75 wt-%, at least 80 wt-%, or at least 90 wt-% in liquid phase, or 100 wt-% in liquid phase.