Method of upgrading low-value linear alpha-olefins of C18 or more

1. A method of manufacturing lube base oil from linear alpha-olefin, comprising:

a) providing one or more linear alpha-olefin(s) having 18 or more carbons;

b) converting the linear alpha-olefin(s) into linear internal-olefin(s) having 18 or more carbons by a double bond shift reaction at a temperature ranging from 250° C. to less than 400° C. in the presence of a catalyst having weak acid sites; and

c) oligomerizing the linear internal-olefin(s), thus synthesizing a lube base oil having an X-shaped hydrocarbon;

wherein

in b), a weight reduction of the linear internal-olefin(s) relative to the linear alpha-olefin(s) is 5% or less;

in c), the X-shaped hydrocarbon in the lube base oil range has a α/β value of 1-10 (where α is a number of carbon atoms of a longest carbon chain in the X-shaped hydrocarbon, and β is a number of carbon atoms of a shortest carbon chain in the X-shaped hydrocarbon), and includes a dimer (D) and a trimer or higher oligomers (T+) X-shaped hydrocarbon of the linear internal-olefin(s), with a D/T+ weight ratio ranging from 0.1 to 100;

wherein the catalyst having weak acid sites is a mesoporous catalyst or a macroporous catalyst and the double bond shift reaction is conducted in mesopores of the mesoporous catalyst or macropores of the macroporous catalyst, and

wherein the catalyst having a weak acid site is one or more catalyst selected from the group consisting of alumina, silica-alumina, zirconia, titania, iron oxide, vanadium oxide, zeolite, and alumina-supported mesoporous silica.

2. The method of claim 1 , wherein the one or more linear alpha-olefin(s) having 18 or more carbons is one or more linear alpha-olefin(s) having 18 or more carbons having an even number of carbon atoms, derived from a C4-C40 full range linear alpha-olefin produced by ethylene polymerization or oligomerization.

3. The method of claim 2 , wherein the one or more linear alpha-olefin(s) having 18 or more carbons further comprises one or more linear alpha-olefin(s) having 18 or more carbons derived from Fischer-Tropsch reaction.

4. The method of claim 1 , wherein the number of carbon atoms of the longest carbon chain in a molecular structure of the X-shaped hydrocarbon in the lube base oil range is 20-60.

5. The method of claim 1 , wherein b) is performed at a temperature of 300-375° C.

6. The method of claim 1 , wherein b) is performed at a pressure of 4-10 bar.

7. The method of claim 1 , wherein b) is performed in a fixed bed reactor.

8. The method of claim 7 , wherein b) is performed at a weight hourly space velocity (WHSV) of 0.01-50 hr −1 and at an inactive carrier gas flow rate of 10-1000 sccm.

9. The method of claim 8 , wherein the inactive carrier gas is nitrogen, argon, helium, or a mixture thereof.

10. The method of claim 1 , wherein the alumina has a BET specific surface area of at least 150 m 2 /g, an average pore size of at least 5 nm, and a total pore volume of 0.5-1.3 cc/g.

11. The method of claim 1 , wherein the linear internal-olefin(s) having 18 or more carbons produced in b) contains at least 25 wt % of a one or more center linear internal-olefin(s) having 18 or more carbons.

12. The method of claim 1 , wherein the one or more linear alpha-olefin(s) having 18 or more carbons is one or more linear alpha-olefin(s) having 20 or more carbons.

13. The method of claim 1 , wherein c) is performed in the presence of a cationic polymerization catalyst, wherein the cationic polymerization catalyst comprises zeolite, clay, SAPO, AlPO, or a catalyst configured such that aluminum (Al) is supported on mesoporous silica.

14. The method of claim 13 , wherein the clay is montmorillonite, and wherein the zeolite is a Y-zeolite having a silica alumina ratio of 30-150, an RFCC catalyst, or beta-zeolite.

15. The method of claim 1 , wherein c) is performed at a temperature of 120-400° C.

16. The method of claim 1 , wherein c) is performed in an oxygen-containing atmosphere using a batch reactor.

17. The method of claim 1 , wherein c) is performed using a continuous reactor at a weight hourly space velocity (WHSV) of 0.01-10 hr −1 .

18. The method of claim 1 , further comprising performing hydrogenation to remove a double bond from the lube base oil, after c).

19. The method of claim 1 , further comprising performing isomerization of the linear internal-olefins(s) and/or the lube base oil to additionally improve low-temperature properties, before and/or after c).

20. The method of claim 19 , wherein the lube base oil in c) is lube base oil satisfying requirements of Group III+.