Process for hydrotreating heavy raw oils

1. A catalyst combination for hydrotreating raw oils, comprising:

one or both of at least one hydrogenation protection catalyst I and at least one hydrogenation demetalling catalyst I;

at least one hydrogenation demetalling catalyst II; and

at least one hydrogenation treatment catalyst III;

wherein a volume percentage of said hydrogenation demetalling catalyst II in said catalyst combination, based on a total volume of the catalyst combination, is 5-50%;

wherein said hydrogenation demetalling catalyst II comprises a shaped alumina support, the support has a pore volume measured by the mercury porosimetry of 0.9-1.2 mL/g, a specific surface area of 50-300 m 2 /g, a ratio of the volume of the pores having a diameter of 10 nm-30 nm to the total pore volume of 55-80%, and a ratio of the volume of the pores having a diameter of 300 nm-500 nm to the total pore volume of 18-35%.

2. The catalyst combination of claim 1 , wherein the catalyst combination comprises the hydrogenation protection catalyst I, the hydrogenation demetalling catalyst II and the hydrogenation treatment catalyst III, wherein, based on the total volume of the catalyst combination, a volume percentage of the hydrogenation protection catalyst I is 5-60%, the volume percentage of the hydrogenation demetalling catalyst II is 5-50%, and a volume percentage of the hydrogenation treatment catalyst III is 10-60%; the hydrogenation protection catalyst I has a bed voidage of 25-60%;

or

the catalyst combination comprises the hydrogenation demetalling catalyst I, the hydrogenation demetalling catalyst II and the hydrogenation treatment catalyst III, wherein, based on the total volume of the catalyst combination, a volume percentage of the hydrogenation demetalling catalyst I is 5-60%, a volume percentage of the hydrogenation demetalling catalyst II is 5-50%, and a volume percentage of the hydrogenation treatment catalyst III is 10-60%.

3. The catalyst combination of claim 1 , wherein the hydrogenation protection catalyst I comprises at least one hydrogenation active metal element and a support,

wherein the hydrogenation active metal element of the hydrogenation protection catalyst I comprises at least one metal element selected from the group consisting of the metal elements in the group VIII of the Periodic Table and at least one metal element selected from the group consisting of the metal elements in the group VIB of the Periodic Table,

wherein, calculated as oxide and based on a weight of the hydrogenation protection catalyst I, the weight percentage of the metal element in the group VIII of the Periodic Table is from more than zero to no more than 5 wt %,

wherein, calculated as oxide and based on a weight of the hydrogenation protection catalyst I, the weight percentage of the metal element in the group VIB of the Periodic Table is from more than zero to no more than 10 wt %, and

wherein the support has a crushing strength of 20-300 N/particle, a pore volume of 0.3-0.9 mL/g, and a specific surface area of from more than 30 m 2 /g to no more than 150 m 2 /g.

4. The catalyst combination of claim 1 , wherein the hydrogenation protection catalyst I has a support that is a titanium oxide-alumina shaped body, and the support of the hydrogenation protection catalyst I has an alumina weight percentage of 70-99 wt %, and a titanium oxide weight percentage of 1-30 wt %, based on a weight of the support.

5. The catalyst combination of claim 1 , wherein the hydrogenation demetalling catalyst I comprises a support that is a shaped alumina support and at least one hydrogenation active metal element,

wherein the shaped alumina support has a total pore volume of 0.8 mL/g-1.2 mL/g, a specific surface area of 90 m 2 /g-230 m 2 /g, an average pore diameter of 25 nm-35 nm, and a ratio of the volume of the pores having a diameter of 10 nm-60 nm to the total pore volume of 95%-99.8%,

wherein the at least one hydrogenation active metal element of the hydrogenation demetalling catalyst I comprises at least one metal element selected from the group consisting of the metal elements in the group VIII of the Periodic Table and at least one metal element selected from the group consisting of the metal elements in the group VIB of the Periodic Table,

wherein, calculated as oxide and based on a weight of the hydrogenation demetalling catalyst I, the weight percentage of the metal element in the group VIII of the Periodic Table is from more than zero to no more than 5 wt %; and

wherein, calculated as oxide and based on a weight of the hydrogenation demetalling catalyst I, the weight percentage of the metal element in the group VIB of the Periodic Table is from more than zero to no more than 15 wt %.

6. The catalyst combination of claim 1 , wherein the hydrogenation demetalling catalyst II comprises at least one hydrogenation active metal element, wherein the at least one hydrogenation active metal element of the hydrogenation demetalling catalyst II is a combination of at least one metal element selected from the group consisting of the metal elements in the group VIII of the Periodic Table and at least one metal element selected from the group consisting of the metal elements in the group VIB of the Periodic Table, and

wherein, calculated as oxide and based on a weight of the hydrogenation demetalling catalyst II, the weight percentage of the metal element in the group VIII of the Periodic Table is from more than zero to more than 3 wt %; and, calculated as oxide and based on the weight of the hydrogenation demetalling catalyst II, the weight percentage of the metal element in the group VIB of the Periodic Table is from more than zero to no more than 15 wt %.

7. The catalyst combination of claim 1 , wherein the hydrogenation treatment catalyst III comprises

at least one support selected from the group consisting of alumina, silica-alumina, and a combination thereof;

at least one hydrogenation active metal element selected from the group consisting of nickel, cobalt, molybdenum, tungsten and a combination thereof; and

optionally at least one auxiliary agent selected from the group consisting of fluorine, boron, phosphorus, and a combination thereof.

8. The catalyst combination of claim 1 , wherein said hydrogenation demetalling catalyst II comprises a shaped boron-containing alumina support, wherein the support has a boron weight percentage of 0.1-6 wt %, calculated based on B 2 O 3 .

9. The catalyst combination of claim 1 , wherein the support of hydrogenation demetalling catalyst II has a ratio of the volume of the pores having a diameter of 10 nm-30 nm to the total pore volume of 55-72%.

10. The catalyst combination of claim 9 , wherein the support of hydrogenation demetalling catalyst II has a ratio of the volume of the pores having a diameter of 10 nm-30 nm to the total pore volume of 59-66%.

11. The catalyst combination of claim 1 , wherein the support of hydrogenation demetalling catalyst II has a ratio of the volume of the pores having a diameter of 300 nm-500 nm to the total pore volume of 26-32%.

12. The catalyst combination of claim 6 , wherein the weight percentage of the metal element in the group VIII of the Periodic Table is from more than zero to no more than 0.8 wt %, and the weight percentage of the metal element in the group VIB of the Periodic Table is from more than zero to no more than 4 wt %.

13. The catalyst combination of claim 12 , wherein the weight percentage of the metal element in the group VIII of the Periodic Table is from more than 0.1 to no more than 0.6 wt %, and the weight percentage of the metal element in the group VIB of the Periodic Table is from more than 1.5 to no more than 3.5 wt %.

14. The catalyst combination of claim 6 , wherein the metal element in the group VIII of the Periodic Table is nickel and/or cobalt; the metal element in the group VIB of the Periodic Table is molybdenum and/or tungsten.

15. The catalyst combination of claim 7 , wherein the hydrogenation treatment catalyst III comprises nickel and/or cobalt, and molybdenum and/or tungsten, calculated as oxide and based on the catalyst III, the weight percentage of nickel and/or cobalt is 1-5 wt %, and the weight percentage of molybdenum and/or tungsten is 10-35 wt %;

wherein calculated as the element, the weight percentage of at least one auxiliary agent selected from the group consisting of fluorine, boron, phosphorus and a combination thereof is 0-9 wt %.

16. The catalyst combination of claim 1 , wherein the shaped alumina support of hydrogenation demetalling catalyst II is prepared by mixing a pseudoboehmite-containing hydrated alumina P1 and a P1's modifier P2, optionally introducing a boron-containing compound, shaping the resulting mixture, and drying and calcining the resulting shaped bodies, wherein the weight mixing ratio of P1 to P2 is 20-95:5-80; wherein the P2 is prepared by one of the following methods:

(1) shaping the pseudoboehmite-containing hydrated alumina P1; drying the shaped bodies of P1 40-350° C. for 1-24 hrs, grounding and sieving some or all of the dried shaped bodies of P1 to obtain P2 as powder;

(2) calcining the shaped bodied obtained in the above (1) at a temperature of from 350° C. to no more than 1400° C. for 1-8 hrs, grounding and sieving some or all of the calcined shaped bodies of P1 to obtain P2 as powder;

(3) flash-drying the pseudoboehmite-containing hydrated alumina P1 at a temperature of from more than 150° C. to no more than 1400° C. for 0.05-1 hr to obtain P2 as powder; and

(4) combining two or more powders obtained from the above (1), (2) and/or (3).

17. The catalyst combination of claim 1 , wherein the shaped alumina support is produced by mixing a pseudoboehmite-containing hydrated alumina P1 and a modifier P2 made from the pseudoboehmite-containing hydrated alumina and drying and calcining the mixture comprising P1 and P2.

18. A process for hydrotreating raw oils, comprising:

contacting a heavy raw oil feedstock with the catalyst combination of claim 1 under a first set of conditions or a second set of conditions,

wherein the first set of conditions comprises a hydrogen partial pressure of 6-20 MPa, a temperature of 300-450° C., a liquid-volume hourly space velocity of 0.1-1.0 h −1 , and a hydrogen/oil volume ratio of 600-1500,

wherein the second set of conditions comprise a hydrogen partial pressure of 10-18 MPa, a temperature of 350-420° C., a liquid-volume hourly space velocity of 0.2-0.6 h −1 , and a hydrogen/oil volume ratio of 750-1100, and

wherein the heavy raw oil feedstock comes into contact firstly with the hydrogenation protection catalyst I and/or the hydrogenation demetalling catalyst I, secondly with the hydrogenation demetalling catalyst II, and thirdly with the hydrogenation treatment catalyst III.

19. The process of claim 18 , wherein said heavy raw oil comprises one or more components selected from the group consisting of an asphaltine content>7 wt %, a Fe+Ca content>20 ppmw, a Ni+V content>80 ppmw, a sulfur content>3 wt %, and a residual carbon content>10 wt %.