U.S. patent application number 13/820839 was filed with the patent office on 2013-09-26 for method for producing lubricating base oil with low cloud point and high viscosity index.
This patent application is currently assigned to Dalian Institute of Chemical Physics (DICP), Chinese Academy of Sciences (CAS). The applicant listed for this patent is Kebin Chi, Shanbin Gao, Sheng Hu, Wenle Li, Yanfeng Liu, Xiangbin Meng, Mingwei Tan, Zhijian Tian, Bingchun Wang, Lei Wang, Yunpeng Xu, Lijun Yan, Jinling Zhu. Invention is credited to Kebin Chi, Shanbin Gao, Sheng Hu, Wenle Li, Yanfeng Liu, Xiangbin Meng, Mingwei Tan, Zhijian Tian, Bingchun Wang, Lei Wang, Yunpeng Xu, Lijun Yan, Jinling Zhu.
Application Number | 20130253238 13/820839 |
Document ID | / |
Family ID | 43434546 |
Filed Date | 2013-09-26 |
United States Patent
Application |
20130253238 |
Kind Code |
A1 |
Hu; Sheng ; et al. |
September 26, 2013 |
METHOD FOR PRODUCING LUBRICATING BASE OIL WITH LOW CLOUD POINT AND
HIGH VISCOSITY INDEX
Abstract
The present invention relates to a method for producing
lubricating base oil with a low cloud point and a high viscosity
index. In the method, a lubricating base oil with a low pour point,
a low cloud point and a high viscosity index is produced by a
hydrorefining-isomerization/asymmetrical cracking-hydrofinishing in
the presence of hydrogen, wherein a highly waxy heavy fraction oil
having an initial boiling point of 300.degree. C. to 460.degree.
C., a wax content of 5% or more, a pour point of -20.degree. C. or
more and a cloud point of -5.degree. C. or more is used as a raw
material, and naphtha and middle fraction oil being co-produced.
The method is characterized mainly in the high yield of heavy base
oil, a low pour point and cloud point, a high viscosity and
viscosity index of the base oil.
Inventors: |
Hu; Sheng; (Beijing, CN)
; Tian; Zhijian; (Dalian City, CN) ; Yan;
Lijun; (Beijing, CN) ; Li; Wenle; (Beijing,
CN) ; Xu; Yunpeng; (Dalian City, CN) ; Chi;
Kebin; (Beijing, CN) ; Meng; Xiangbin;
(Beijing, CN) ; Wang; Bingchun; (Dalian City,
CN) ; Tan; Mingwei; (Beijing, CN) ; Wang;
Lei; (Dalian City, CN) ; Liu; Yanfeng;
(Beijing, CN) ; Zhu; Jinling; (Beijing, CN)
; Gao; Shanbin; (Beijing, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hu; Sheng
Tian; Zhijian
Yan; Lijun
Li; Wenle
Xu; Yunpeng
Chi; Kebin
Meng; Xiangbin
Wang; Bingchun
Tan; Mingwei
Wang; Lei
Liu; Yanfeng
Zhu; Jinling
Gao; Shanbin |
Beijing
Dalian City
Beijing
Beijing
Dalian City
Beijing
Beijing
Dalian City
Beijing
Dalian City
Beijing
Beijing
Beijing |
|
CN
CN
CN
CN
CN
CN
CN
CN
CN
CN
CN
CN
CN |
|
|
Assignee: |
Dalian Institute of Chemical
Physics (DICP), Chinese Academy of Sciences (CAS)
Dalian City
CN
PetroChina Company Limited
Beijing
CN
|
Family ID: |
43434546 |
Appl. No.: |
13/820839 |
Filed: |
June 3, 2011 |
PCT Filed: |
June 3, 2011 |
PCT NO: |
PCT/CN11/00946 |
371 Date: |
March 5, 2013 |
Current U.S.
Class: |
585/253 ;
208/57 |
Current CPC
Class: |
C10G 45/58 20130101;
B01J 35/1047 20130101; C10G 47/18 20130101; C10G 2300/304 20130101;
C10G 2300/4018 20130101; C10G 2300/301 20130101; C10G 2300/302
20130101; B01J 29/7484 20130101; B01J 29/005 20130101; B01J 29/44
20130101; B01J 29/7492 20130101; B01J 35/1042 20130101; B01J 23/42
20130101; C10G 2400/10 20130101; C10G 2300/1074 20130101; B01J
35/1019 20130101; B01J 29/85 20130101; C10G 2400/02 20130101; C10G
2300/1022 20130101; C10G 65/12 20130101; C10G 69/02 20130101; C10G
45/08 20130101 |
Class at
Publication: |
585/253 ;
208/57 |
International
Class: |
C10G 69/02 20060101
C10G069/02 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 7, 2010 |
CN |
201010274479.X |
Claims
1. A method for producing a lubricating base oil with a low cloud
point and a high viscosity index, wherein the cloud point is lower
than -5.degree. C., and the viscosity index is higher than 120, the
method comprises: producing a lubricating base oil by a
hydrorefining-isomerization/asymmetrical cracking-hydrofinishing in
the presence of hydrogen, wherein a highly waxy heavy fraction oil
having an initial boiling point of 300.degree. C. to 460.degree.
C., a wax content of 5% or more, a pour point of -20.degree. C. or
more and a cloud point of -5.degree. C. or more is used as a raw
material; (1) during the hydrorefining process, a wax-containing
heavy feed stock contacts a pre-refining catalyst, and is subjected
to desulfurization, denitrogenation, aromatic saturation and a
ring-opening reaction, a light product generated in the
hydrorefining process is separated by a stripping column as a
byproduct, and a heavy product enters an isomerization-asymmetrical
cracking process; the operating conditions of the hydrorefining
process are: reaction temperature: 350.degree. C. to 410.degree.
C., hydrogen partial pressure: 10 MPa to 18 MPa, space velocity:
0.5 h.sup.-1 to 2.0 h.sup.-1, volume ratio of hydrogen to oil:300
Nm.sup.3/m.sup.3 to 1000 Nm.sup.3/m.sup.3; the pre-refining
catalyst comprises 60 wt % to 90 wt % of one or more of alumina,
silica and titania, and 10 wt % to 40 wt % of one or more of
molybdenum trioxide, tungsten trioxide, nickel oxide and cobalt
oxide; (2) during the hydrogenation isomerization-asymmetrical
cracking process, the heavy product generated in the hydrorefining
process contacts an isomerization-asymmetrical cracking catalyst,
wax-containing component having a high pour point is subjected to
an isomerization-asymmetrical cracking reaction, and is converted
into a an isomer and an asymmetrical cracking product having a low
pour point, which then directly enters a hydrofinishing process;
the operating conditions of the hydrogenation
isomerization-asymmetrical cracking process are: reaction
temperature: 260.degree. C. to 410.degree. C., hydrogen partial
pressure: 10 MPa to 18 MPa, volume space velocity: 0.5 h.sup.-1 to
3.0 h.sup.-1, volume ratio of hydrogen to oil:300 Nm.sup.3/m.sup.3
to 1000 Nm.sup.3/m.sup.3; the catalyst: the content of mesoporous
molecular sieve is 40% to 80%, the content of Pt and/or Pd is 0.3
wt % to 0.7 wt %, and alumina as the balance; (3) during the
hydrofinishing process, an isomerization-asymmetrical cracking
reaction product having a low pour point contacts a hydrofinishing
catalyst, residual aromatics and olefins generated by the
asymmetrical cracking reaction are hydrogenated and saturated, and
the resulting product is separated by a fractionating column to
obtain a lubricating base oil and gaseous hydrocarbons, naphtha and
middle fraction oil; the catalyst comprises amorphous
silica-alumina and at least one group VIII noble metal, the weight
ratio of SiO.sub.2:Al.sub.2O.sub.3 is 1:1.about.9, the average pore
size is 1.0 nm to 5.0 nm, the pore volume is 0.3 ml/g to 1.0 mug,
the BET specific surface area is 260 m.sup.2/g to 450 m.sup.2/g;
the noble metal is Pt and/or Pd, and the content of the noble metal
is 0.3 wt % to 0.6 wt %; and the hydrofinishing reaction conditions
are: reaction temperature: 180.degree. C. to 320.degree. C.,
hydrogen partial pressure: 10 MPa to 18 MPa, volume space velocity:
0.5 h.sup.-1 to 3.0 h.sup.-1, volume ratio of hydrogen to oil:300
Nm.sup.3/m.sup.3 to 1000 Nm.sup.3/m.sup.3.
2. The method for producing a lubricating base oil with a low cloud
point of and a high viscosity index according to claim 1, wherein
the heavy feed stock comprises anyone of furfural refined oil,
foots oil, cerate, propane deasphalted oil, hydrocracking UCO,
vacuum gas oil and Fischer-Tropsch wax or a mixture thereof.
3. The method for producing a lubricating base oil with a low cloud
point of and a high viscosity index according to claim 1, wherein
the mesoporous molecular sieve used in the hydrogenation
isomerization-asymmetrical cracking reaction catalyst is one of a
ZSM-22/ZSM-23 composite molecular sieve, a ZSM-23/ZSM-22 composite
molecular sieve, a ZSM-22/SAPO-11 composite molecular sieve, a
ZSM-23/SAPO-11 composite molecular sieve, a ZSM-5/SAPO-11 composite
molecular sieve and an EU-1/SAPO-11 composite molecular sieve.
4. A method for producing a lubricating base oil comprising: (1)
contacting a wax-containing heavy feed stock with a pre-refining
catalyst and separating a light product from a heavy product; (2)
contacting the heavy product with an isomerization-asymmetrical
cracking catalyst wherein a wax-containing component having a high
pour point is subjected to an isomerization-asymmetrical cracking
reaction, and is converted into an isomer and an asymmetrical
cracking product having a low pour point; (3) contacting the isomer
and the isomerization-asymmetrical cracking reaction product having
a low pour point with a hydrofinishing catalyst to generate a
product; and (4) separating the product by a fractionating column
to obtain a lubricating base oil and gaseous hydrocarbons, naphtha
and middle fraction oil.
5. The method of claim 4, wherein the lubricating base oil has a
low cloud point and a high viscosity index.
6. The method of claim 5, wherein the cloud point is lower than
-5.degree. C., and the viscosity index is higher than 120.
7. The method of claim 4, wherein the wax-containing heavy feed
stock has an initial boiling point of 300.degree. C. to 460.degree.
C., a wax content of 5% or more, a pour point of -20.degree. C. or
more and a cloud point of -5.degree. C.
8. The method of claim 4, wherein the contacting at step (1)
subjects the wax-containing heavy feed stock to desulfurization,
denitrogenation, aromatic saturation and a ring-opening
reaction.
9. The method of claim 4, wherein operating conditions of the
contacting at step (1) comprise a reaction temperature of from
350.degree. C. to 410.degree. C.; a hydrogen partial pressure of 10
MPa to 18 MPa; a space velocity of from 0.5 h.sup.-1 to 2.0
h.sup.-1; and a volume ratio of hydrogen to oil of from 300
Nm.sup.3/m.sup.3 to 1000 Nm.sup.3/m.sup.3.
10. The method of claim 4, wherein the pre-refining catalyst
comprises from 60 wt. % to 90 wt. % of one or more of alumina,
silica and titania; and 10 wt. % to 40 wt. % of one or more of
molybdenum trioxide, tungsten trioxide, nickel oxide and cobalt
oxide.
11. The method of claim 4, wherein the contacting at step (2)
subjects the heavy product is subjected to an
isomerization-asymmetrical cracking reaction, and is converted into
a an isomer and an asymmetrical cracking product having a low pour
point.
12. The method of claim 4, wherein operating conditions of the
contacting at step (2) comprise a reaction temperature of from
260.degree. C. to 410.degree. C.; a hydrogen partial pressure of
from 10 MPa to 18 MPa; a volume space velocity of from 0.5 h.sup.-1
to 3.0 h.sup.-1; and a volume ratio of hydrogen to oil of from 300
Nm.sup.3/m.sup.3 to 1000 Nm.sup.3/m.sup.3.
13. The method of claim 4, wherein the isomerization-asymmetrical
cracking catalyst comprises 40% to 80% mesoporous molecular sieve;
a Pt and/or Pd content of 0.3 wt % to 0.7 wt %; and alumina as the
balance.
14. The method of claim 13, wherein the mesoporous molecular sieve
is at least one of a ZSM-22/ZSM-23 composite molecular sieve, a
ZSM-23/ZSM-22 composite molecular sieve, a ZSM-22/SAPO-11 composite
molecular sieve, a ZSM-23/SAPO-11 composite molecular sieve, a
ZSM-5/SAPO-11 composite molecular sieve or an EU-1/SAPO-11
composite molecular sieve.
15. The method of claim 4, wherein the contacting at step (3)
hydrogenates and saturates residual aromatics and olefins generated
by the asymmetrical cracking reaction.
16. The method of claim 4, wherein operating conditions of the
contacting at step (3) comprise a reaction temperature of from
180.degree. C. to 320.degree. C.; a hydrogen partial pressure of
from 10 MPa to 18 MPa; a volume space velocity of from 0.5 h.sup.-1
to 3.0 h.sup.-1; and a volume ratio of hydrogen to oil of from 300
Nm.sup.3/m.sup.3 to 1000 Nm.sup.3/m.sup.3.
17. The method of claim 4, wherein the hydrofinishing catalyst
comprises amorphous silica (SiO.sub.2)-alumina (Al.sub.2O.sub.3)
and at least one group VIII noble metal, wherein the weight ratio
of SiO.sub.2:Al.sub.2O.sub.3 is 1:1.about.9; the average pore size
is from 1.0 nm to 5.0 nm; the pore volume is from 0.3 mL/g to 1.0
mL/g; the BET specific surface area is from 260 m.sup.2/g to 450
m.sup.2/g; the noble metal is Pt and/or Pd; and the content of the
noble metal is from 0.3 wt % to 0.6 wt %.
18. The method of claim 4, wherein the isomer and an asymmetrical
cracking product having a low pour point directly enter the
contacting at step (3).
19. The method of claim 4, wherein the heavy feed stock comprises
any one of furfural refined oil, foots oil, cerate, propane
deasphalted oil, hydrocracking UCO, vacuum gas oil and
Fischer-Tropsch wax or a mixture thereof.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a method for producing a
lubricating base oil with a low cloud point (<-5.degree. C.) and
a high viscosity index (>120).
BACKGROUND OF THE INVENTION
[0002] Patent CN101134910A discloses a method for lowering the pour
point and the cloud point of a lubricating oil distillate. In the
method, a catalytic dewaxing process is adopted, and the catalyst
includes nickel metal as an active component, which is contained in
a support of a ZSM-5 molecular sieve. The pour point of a light
deasphalted hydrotreated oil can be lowered from 9.degree. C. to
-24.degree. C., and the cloud point can be lowered from 12.degree.
C. to -16.degree. C. The method has the following obvious
disadvantage: the yield and the viscosity of the base oil product
will be greatly decreased when the wax content in the feed stock is
high, and the drops of the pour point and the cloud point need to
be increased.
[0003] Patent CN1524929 discloses a method for lowering the cloud
point of a lubricating base oil, in which a lube stock is first
subjected to solvent pre-dewaxing, the pour point of the dewaxed
oil is -5.degree. C. to 15.degree. C.; the pre-dewaxed oil is
subjected to hydrotreating to reduce the sulfur content and the
nitrogen content; the pre-dewaxed oil after hydrotreating is
subjected to isodewaxing, to obtain a lubricating base oil with a
low cloud point. In order to avoid increase of the severity of the
reaction and a resulted severe cracking reaction, in the method,
most of the wax needs to be removed through a solvent pre-dewaxing
process, and then a hydrotreating and isodewaxing process is
performed. The pour point of the dewaxed oil of the method should
be not higher than 15.degree. C., otherwise the cloud point of the
isomerization product cannot be lowered to less than 0.degree. C.,
even cannot be lowered to less than 5.degree. C.
[0004] U.S. Pat. No. 6,699,385 discloses a method for lowering the
cloud point through an isodewaxing process. In order to avoid
increase of the severity of the reaction and a resulted severe
cracking reaction, the waxy feed stock needs to be first
fractionated, and a light fraction is subjected to isodewaxing, and
the cloud point can only be decreased to about 0.degree. C.
[0005] All the methods for dewaxing a lubricating base oil
disclosed in the published patents and documents above do not
clarify or imply a method for producing a base oil with a low pour
point, a low cloud point and a high viscosity index by an
isomerization-asymmetrical cracking reaction process, and compared
with the method disclosed in the published patents and documents,
the yield of a base oil, especially the yield of a heavy base oil
of an isomerization-symmetric cracking reaction process is
higher.
SUMMARY OF THE INVENTION
[0006] The present invention is directed to a method for producing
a lubricating base oil having a low cloud point (<-5.degree. C.)
and a high viscosity index (>120), wherein a highly waxy heavy
fraction oil having an initial boiling point of 300.degree. C. to
460.degree. C., a wax content of 5% or more, a pour point of
-20.degree. C. or more and a cloud point of -5.degree. C. or more
is used as raw material to produce a API (American Petroleum
Institute) II, III (see the classification standard in Table 1)
type lubricating base oil having a low pour point and a high
viscosity index by a hydrogenation
pre-refining-isomerization/asymmetrical cracking-supplementary
refining three-stage hydrogenation process.
[0007] The production method provided by the present invention
includes: (1) a hydrorefining process: at a certain hydrogen
pressure, a waxy feed stock contacts a hydrorefining catalyst and
is subjected to desulfurization, denitrogenation, aromatic
saturation and an ring-opening reaction, products of the
hydrorefining reaction are separated by a stripping column, and the
bottom fraction enters a hydroisomerization/asymmetrical cracking
process; (2) a hydroisomerization/asymmetrical cracking process: at
a certain hydrogen pressure, a bottom product of the stripping
column contacts an isomerization-asymmetrical cracking catalyst and
is subjected to isomerization-asymmetrical cracking and a
hydrogenation saturation reaction, to obtain a product having a low
pour point, a low cloud point, a low aromatic content and a high
viscosity index, and then all the product directly enters a
hydrofinishing process; (3) a hydrofinishing process: at a certain
hydrogen pressure, the isomerization-asymmetrical cracking reaction
product contacts a hydrofinishing catalyst and is subjected to a
hydrogenation saturation reaction, to obtain a hydrofinishing oil
having good light stability and thermal stability; and (4) a
product separation process: the product obtained in the
hydrofinishing process is separated into a gas phase product and a
liquid phase product by a hot high-pressure separator and a cold
low-pressure separator, the liquid product passes through a
normal-pressure fractionating column and a reduced-pressure
fractionating column to extract naphtha, kerosene, diesel oil and
light, middle and heavy lubricating base oil having a low pour
point and a high viscosity index.
[0008] According to the method of the present invention, the feed
stock includes anyone of furfural refined oil, foots oil, cerate
(soft wax), propane deasphalted oil (DAO), hydrocracking
unconverted oil (UCO), Fischer-Tropsch wax, vacuum gas oil and
other waxy oils or a mixture thereof.
[0009] According to the method of the present invention, the
hydrorefining catalyst includes 60 wt % to 90 wt % of one or more
of alumina, silica and titania, and 10 wt % to 40 wt % of one or
more of molybdenum trioxide, tungsten trioxide, nickel oxide and
cobalt oxide.
[0010] According to the method of the present invention, before
use, the hydrorefining catalyst is pre-sulfurated by hydrogen
sulfide or sulfur-containing feed stock at a temperature of 150 to
350.degree. C. in the presence of hydrogen. This type of
pre-vulcanization may be carried out ex situ or in situ.
[0011] According to the method of the present invention, the
hydrorefining process conditions are: reaction temperature:
350.degree. C. to 410.degree. C., hydrogen partial pressure: 10 MPa
to 18 MPa, space velocity (LHSV): 0.5 h.sup.-1 to 2.0 h.sup.-1, and
volume ratio of hydrogen to oil:300 Nm.sup.3/m.sup.3 to 1000
Nm.sup.3/m.sup.3.
[0012] According to the method of the present invention, the oil
obtained by stripping separation of the hydrorefining product has a
total sulfur content of no higher than 10 .mu.g/g and a total
nitrogen content of no higher than 5 .mu.g/g.
[0013] According to the method of the present invention, the
isomerization-asymmetrical cracking catalyst is at least one of the
following one-dimensional 10-membered ring mesoporous composite
molecular sieves: a ZSM-22/ZSM-23 composite molecular sieve, a
ZSM-23/ZSM-22 composite molecular sieve, a ZSM-5/SAPO-11 composite
molecular sieve, a ZSM-22/SAPO-11 composite molecular sieve, a
ZSM-23/SAPO-11 composite molecular sieve, an EU-1/SAPO-11 composite
molecular sieve, and a NU-87/SAPO-11 composite molecular sieve. The
content of the molecular sieve is 40% to 80%, and the rest is
alumina and at least one group VIII noble metal, where the noble
metal is Pt and/or Pd and has a content of 0.3 wt % to 0.6 wt %.
The average pore diameter of the catalyst is 0.3 nm to 0.8 nm, the
average pore volume is 0.1 ml/g to 0.4 mug, and the BET specific
surface area is 120 m.sup.2/g to 300 m.sup.2/g.
[0014] According to the method of the present invention, before
use, the isomerization/asymmetrical cracking catalyst needs to be
pre-reduced at a temperature of 150 to 450.degree. C. in the
presence of hydrogen.
[0015] According to the method of the present invention, the
isomerization/asymmetrical cracking process conditions are:
reaction temperature: 260.degree. C. to 410.degree. C., hydrogen
partial pressure: 10 MPa to 18 MPa, volume space velocity: 0.5
h.sup.-1 to 3.0 h.sup.-1, volume ratio of hydrogen to oil:300
Nm.sup.3/m.sup.3 to 1000 Nm.sup.3/m.sup.3.
[0016] According to the method of the present invention, the
hydrofinishing catalyst includes amorphous silica-alumina and at
least one group VIII noble metal.
[0017] According to the method of the present invention, the
hydrofinishing catalyst has a ratio of SiO.sub.2:Al.sub.2O.sub.3 of
1:1 to 9, an average pore radius of 1.0 nm to 5.0 nm, a pore volume
of 0.3 ml/g to 1.0 ml/g, and a BET specific surface area of 260
m.sup.2/g to 450 m.sup.2/g. The noble metal is Pt and/or Pd, and
the content of the noble metal is 0.3 wt % to 0.6 wt %.
[0018] According to the method of the present invention, before
use, the hydrofinishing catalyst is generally pre-reduced at a
temperature of 150.degree. C. to 450.degree. C. in the presence of
hydrogen.
[0019] According to the method of the present invention, the
hydrofinishing reaction conditions are: reaction temperature:
180.degree. C. to 320.degree. C., hydrogen partial pressure: 10 MPa
to 18 MPa, volume space velocity: 0.5 h.sup.-1 to 3.0 h.sup.-1,
volume ratio of hydrogen to oil:300 Nm.sup.3/m.sup.3 to 1000
Nm.sup.3/m.sup.3.
[0020] According to the method of the present invention, the
normal-pressure distillation and reduced-pressure distillation
process are to separate the oil mixture after supplementary
refining by normal-pressure distillation and reduced-pressure
distillation, to obtain a naphtha, a middle fraction oil and a
lubricating base oil.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 shows product distribution of Example 1 and
Comparative Example 1.
[0022] FIG. 2 shows product distribution of Example 2 and
Comparative Example 2.
[0023] FIG. 3 is a flowchart of an isomerization-asymmetrical
cracking/supplementary refining process of a lubricating base
oil.
[0024] FIG. 4 is a flowchart of a
hydrorefining/isodewaxing/hydrofinishing process of a lubricating
base oil.
[0025] FIG. 5 is a flowchart of a
hydrorefining/isomerization-asymmetrical cracking/hydrofinishing
process of a lubricating base oil.
[0026] FIG. 6 is a flowchart of an isomerization-asymmetrical
cracking/hydrofinishing process of a lubricating base oil.
PREFERRED EMBODIMENTS
Examples
[0027] The present invention is further described with the
following examples.
[0028] The hydrorefining catalyst and the supplementary refining
catalyst used in the examples of the present invention and
preparation method thereof are briefly described as follows:
[0029] Same hydrorefining catalyst and hydrofinishing catalyst are
used in the examples and comparative examples of the present
invention. The hydrorefining catalyst is prepared according to the
following process: pseudo-boehmite having an appropriate pore
structure is selected and used to prepare a strip-like support
having a clover-shaped cross section, after the support is dried
and baked, Ni element and Mo element are loaded on the alumina
support by an impregnation method, and then dried and baked to
obtain a hydrorefining catalyst, wherein the NiO content is 4.20%,
the MoO.sub.3 content is 18.3%, and the rest is alumina, the
specific surface area is 175 m.sup.2/g, and the pore volume is 0.45
cm.sup.3/g.
[0030] The isomerization/asymmetrical cracking catalyst used in the
examples is a 0.5% Pt/ZSM-22/SAPO-11 catalyst prepared according to
the method described in Example 12 of patent CN 1762594A.
[0031] In a method for preparing the hydrofinishing catalyst,
amorphous silica-alumina used as support is prepared by using
cocurrent flow fixed pH value and silica-alumina coprecipitation.
After being dried and baked, the support is squeezed into a strip
having a clover-shaped cross section, and dried and baked, and then
metal Pt is loaded by an impregnation method, and then dried and
baked to obtain a hydrofinishing catalyst, wherein the Pt content
is 0.51%, the rest is silica and alumina, the ratio of
SiO.sub.2:Al.sub.2O.sub.3 is 1:6.3, the specific surface area is
305 cm.sup.2/g, and the pore volume is 1.08 cm.sup.3/g.
Comparative Example 1
[0032] A SAPO-11 molecular sieve was synthesized by a method
described in Example 18 of U.S. Pat. No. 4,440,871. Pseudo-boehmite
is incorporated into a SAPO-11 molecular sieve powder in a ratio of
70% SAPO-11 molecular sieve to 30% pseudo-boehmite, and then a
small amount of an adhesive such as an aqueous solution of
HNO.sub.3 was added, blended and shaped into a strip of .phi.1.2
mm, baked at 110.degree. C. for 24 hours and at 600.degree. C. for
24 hours, and pulverized into particles having a length of 1 mm to
2 mm. A sufficient amount of support particles was impregnated in a
suitable amount of a Pt(NH.sub.3).sub.4Cl.sub.2 solution having a
concentration of 3% for 16 hours by a common pore filling
impregnation method, and then dried at 120.degree. C. for 4 hours
and baked at 480.degree. C. for 8 hours. 200 ml of the prepared
catalyst was pre-reduced by pure hydrogen in situ on a
high-pressure hydrogenation reaction experimental device having a
catalyst load of 200 ml to obtain a 0.5% Pt/SAPO-11 catalyst. The
isodewaxing catalyst reduction conditions are: hydrogen flow rate:
2000 mL/h, the temperature was raised to 250.degree. C. at a rate
of 5.degree. C./min and maintained at 250.degree. C. for 2 hours.
Then, the temperature was raised to 450.degree. C. at a rate of
5.degree. C./min and maintained at 450.degree. C. for 2 hours, and
the reaction temperature was adjusted in a hydrogen flow. The
hydrogenation pre-refining-isodewaxing-hydrofinishing process shown
in FIG. 4 and the process conditions shown in Table 3 were adopted,
paraffin base 650N furfural refined oil was used as a raw material,
of which the physical and chemical properties are shown in Table 2.
The hydrorefining catalyst and the supplementary refining catalyst
were the same as the catalysts used in the examples mentioned
above.
Example 1
[0033] According to the process shown in FIG. 4, the experimental
device and the feed stock were the same as those in Comparative
Example 1. The other reaction conditions were the same as those in
Comparative Example 1 except that the reaction temperature of
isomerization/asymmetrical cracking was 351.degree. C., and the
space velocity was 0.75 h.sup.-1. The reaction conditions of
Comparative Example 1 are shown in Table 3.
[0034] Product distribution comparison of Example 1 and Comparative
Example 1 is shown in Table 4, and main product properties are
shown in Table 5.
[0035] According to the process shown in FIG. 4, paraffin base
200SN lightly dewaxed oil was used as a feed stock in the
experimental device of Comparative Example 1, and the physical and
chemical properties of the feed stock are shown in Table 2. The
reaction conditions are shown in Table 3.
TABLE-US-00001 TABLE 2 Properties of feed stocks of Comparative
Example 1 and Example 1 650SN Analysis Item Furfural Refined Oil
Method 20.degree. C. Density, g/cm.sup.3 0.8721 GB/T 1884 Kinematic
Viscosity 10.16 GB/T 265 (100.degree. C.), mm.sup.2/s Kinematic
Viscosity -- GB/T 265 (40.degree. C.), mm.sup.2/s Viscosity Index
-- GB/T 1995 Pour Point, .degree. C. 60 GB/T 3535 Cloud Point,
.degree. C. >60 GB/T 6986-86 Sulfur Content, .mu.g/g 607 ASTM
D2622 Nitrogen Content, .mu.g/g 322 ASTM D5762 Composition, %
SH/T0753 Saturated Hydrocarbons 86.08 Aromatic Hydrocarbons 13.58
Colloid + Asphaltene 0.34 Distillation Range, .degree. C. HK 421
ASTM D2887 5% 477 10% 498 30% 516 50% 525 70% 533 90% 541 95% 550
KK 557
TABLE-US-00002 TABLE 3 Reaction conditions adopted in Comparative
Example 1 and Example 1 Hydrorefining Isomerization Hydrofinishing
Comparative Comparative Comparative Example 1 Example 1 Example 1
Example 1 Example 1 Example 1 Average 370 370 378 351 230 230
Temperature, .degree. C. Hydrogen 13 13 12 12 12 12 Partial
Pressure, MPa Liquid hourly 0.90 1.00 0.70 0.75 1.50 1.50 Volume
Space Velocity, h.sup.-1 Raito of 500 500 500 500 500 500 Hydrogen
to Oil, Nm.sup.3/m.sup.3
TABLE-US-00003 TABLE 4 Product distribution of Comparative Example
1 and Example 1 Yield, % Product Example 1 Comparative Example 1
Fuel Gas + Naphtha 19.96 15.71 Diesel Oil 2.96 11.58 2 cst Base Oil
3.78 24.86 5 cst Base Oil 0 4.49 10 cst Base Oil 73.30 47.85 Total
Base Oil Yield 77.08 72.71
TABLE-US-00004 TABLE 5 Properties of heavy base oil products of
Comparative Example 1 and Example 1 Comparative Analysis Analysis
Item Example 1 Example 1 Method Initial Boiling Point, .degree. C.
421 385 GB/T 9168 20.degree. C. Density, g/cm.sup.3 0.8424 0.8524
GB/T 1884 Pour Point, .degree. C. -15 -15 GB/T 3535 Cloud Point,
.degree. C. 5 -6 GB/T 6986-86 Aromatic Content, % 1.2 0 Open Flash
Point, .degree. C. 265 270 GB/T 3536 Chroma, number +30 +30 GB/T
3555 Kinematic Viscosity 60.89 61.06 GB/T 265 (40.degree. C.),
mm.sup.2/s Kinematic Viscosity 9.313 9.423 GB/T 265 (100.degree.
C.), mm.sup.2/s Viscosity Index 132 136 GB/T 1995
[0036] It can be seen from Tables 2 to 5 and FIG. 1 that, the pour
point of the feed stock used in the hydrorefining,
isomerization-asymmetrical cracking, hydrofinishing process in
Example 1 is up to 60.degree. C., indicating that the feed stock
contains a large amount of high-carbon-number wax molecules. In the
method of Example 1 and Comparative Example 1, the hydrocracking
reaction occurs simultaneously with isomerization. However,
different from the conventional hydrocracking reaction of
Comparative Example 1, Example 1 has significant features of an
asymmetrical cracking reaction, that is, the cleavage of a C--C
bond preferably occurs at a position close to two ends of a
long-chain paraffin, so that the yields of both small-molecule
products (gas and naphtha) and big-molecule products (10 cst base
oil) are high, and are up to 19.96% and 73.3%, respectively, while
the yields of diesel oil and light base oil (2 cst base oil) are
only 2.96% and 3.78% respectively. The cracking reaction in the
method of Comparative Example 1 occurs at a position close to the
center of a long-chain paraffin, so that the yields of both
small-molecule products (gas+naphtha) and big-molecule products (10
cst base oil) are 15.71% and 47.85% respectively, which are both
lower than those in Example 1, and the yields of diesel oil and
light base oil (2 cst base oil) are 11.58% and 24.86% respectively,
which are both higher than those in Example 1. At the same time,
the cloud point of the heavy base oil product of Example 1 is
11.degree. C. lower than that of the heavy base oil product of
Comparative Example 1. The viscosity index of the heavy base oil
product of Example 1 is higher than that of the heavy base oil
product of Comparative Example 1 by 4%.
Comparative Example 2
[0037] A ZSM-22 molecular sieve was synthesized by the method
described in Example 2 of U.S. Pat. No. 5,783,168. Pseudo-boehmite
is incorporated into a ZSM-22 molecular sieve powder in a ratio of
70% ZSM-22 molecular sieve to 30% pseudo-boehmite, and then a small
amount of an adhesive such as an aqueous solution of HNO.sub.3 was
added, blended and shaped into a strip of .phi.1.2 mm, baked at
110.degree. C. for 24 hours and at 600.degree. C. for 24 hours, and
breaked into particles having a length of 1 mm to 2 mm. A
sufficient amount of support particles was impregnated in a
suitable amount of a Pt(NH.sub.3).sub.4Cl.sub.2 solution having a
concentration of 3% for 16 hours by a common pore filling
impregnation method, and then dried at 120.degree. C. for 4 hours
and baked at 480.degree. C. for 8 hours. 200 ml of the prepared
catalyst was pre-reduced by pure hydrogen in situ in a
high-pressure hydrogenation reaction experimental device having a
catalyst load of 200 ml to obtain 0.5% of Pt/ZSM-22. The catalyst
reduction conditions were the same as those in Comparative Example
1. A paraffin base 200SN dewaxed oil was used as a raw material,
the physical and chemical properties thereof are shown in Table 6,
and a hydrorefining-isodewaxing-hydrofinishing series process
(shown in FIG. 4) and process conditions shown in Table 7 were
adopted.
Example 2
[0038] The process, experimental device and feed stock were the
same as those in Comparative Example 2. The other reaction
conditions were the same as those in Comparative Example 2 except
that the temperature of the isomerization/asymmetrical cracking
reaction was 325.degree. C., and the liquid hourly space velocity
was 1.2 h.sup.-1.
[0039] The product distributions of the reactions of Example 2 and
Comparative Example 2 are shown in Table 8, and main properties of
the products are shown in Table 9.
[0040] It can be seen from Tables 6 to 9 and FIG. 2 that compared
with Comparative Example 2, the method of Example 2 has significant
features of a hydrorefining-isomerization/asymmetrical
cracking-hydrofinishing, that is, the yield of a heavy base oil (5
cst base oil) is high, and the yields of small-molecule products
(gas and naphtha) and big-molecule products (10 cst base oil) are
both high, and are up to 19.96% and 73.3% respectively, the yields
of diesel oil and a light base oil (2 cst base oil) are merely
2.96% and 3.78% respectively. The product distribution is in a
bimodal distribution. At the same time, it can be seen that, the
cloud point of the heavy base oil product of Example 2 is
10.degree. C. lower than that of the heavy base oil product of
Comparative Example 2.
TABLE-US-00005 TABLE 6 Feed stock properties 200SN Analysis Item
Lightly Dewaxed Oil Standard 20.degree. C. Density, g/cm.sup.3
0.8797 GB/T 1884 Kinematic Viscosity 6.277 GB/T 265 (100.degree.
C.), mm.sup.2/s Kinematic Viscosity 40.34 GB/T 265 (40.degree. C.),
mm.sup.2/s Viscosity Index 103 GB/T 1995 Pour Point, .degree. C. -3
GB/T 3535 Cloud Point, .degree. C. 15 GB/T 6986-86 Sulfur Content,
.mu.g/g 420 ASTM D2622 Nitrogen Content, .mu.g/g 144 ASTM D5762
Composition, % SH/T0753 Saturated Hydrocarbons 88.23 Aromatic
Hydrocarbons 11.44 Colloid + Asphaltene 0.33 Distillation Range,
.degree. C. HK 373 ASTM D2887 5% 404 10% 414 30% 429 50% 441 70%
453 90% 478 95% 487 KK 491
TABLE-US-00006 TABLE 7 Reaction conditions of Comparative Examples
1 and 2 Hydrorefining Isomerization Hydrofinishing Comparative
Comparative Comparative Example 2 Example 2 Example 2 Example 2
Example 2 Example 2 Average 368 368 360 325 230 230 Temperature,
.degree. C. Hydrogen 13 13 12 12 12 12 Partial Pressure, MPa Liquid
hourly 1.0 1.0 0.9 1.2 1.5 1.5 Volume Space Velocity, h.sup.-1
Raito of 500 500 500 500 500 500 Hydrogen to Oil,
Nm.sup.3/m.sup.3
TABLE-US-00007 TABLE 8 Product distribution of Examples 1 and 2 and
Comparative Examples 1 and 2 Yield, % Product Comparative Example 2
Example 2 Gas + Naphtha 8.85 9.74 Diesel 8.09 2.44 2 cst Base Oil
18.35 5.14 5 cst Base Oil 67.71 82.68 Total Base Oil Yield 86.06
88.82
TABLE-US-00008 TABLE 9 Properties of heavy base oil products of
Comparative Example 2 and Example 2 Comparative Analysis Analysis
Item Example 2 Example 2 Method Initial Boiling Point, .degree. C.
400 394 GB/T 9168 20.degree. C. Density, g/cm.sup.3 0.8521 0.8629
GB/T 1884 Pour Point, .degree. C. -18 -21 GB/T 3535 Cloud Point,
.degree. C. -5 -15 GB/T 6986-86 Open Flash Point, .degree. C. 220
235 GB/T 3536 Chroma, number +30 +30 GB/T 3555 Kinematic Viscosity
34.56 39.39 GB/T 265 (40.degree. C.), mm.sup.2/s Kinematic
Viscosity, 5.713 6.273 GB/T 265 (100.degree. C.), mm.sup.2/s
Viscosity Index 104 105 GB/T 1995
Example 3
[0041] According to the process shown in FIG. 4, the experimental
device is the same as that in Comparative Example 1, and the feed
stock is a 100N cerate obtained from crude oil by processes of
reduced-pressure distillation, furfural refining and
acetone-toluene dewaxing, of which the physical and chemical
properties are shown in Table 10. Under the process conditions
shown in Table 11, the resulting product distribution is shown in
Table 12, and the main properties of the products are shown in
Table 13.
Example 4
[0042] According to the process shown in FIG. 4, the experimental
device is the same as that in Comparative Example 1, and the feed
stock is a 400N cerate shown in Table 10. Under the process
conditions shown in Table 11, the resulting product distribution is
shown in Table 12, and the main properties of the products are
shown in Table 13.
[0043] It can be seen from Tables 10 to 13 that the distribution of
the product of the isomerization/asymmetrical cracking in Example 3
is similar to those of the products of isomerization/asymmetrical
cracking in Examples 1 and 2, the product mainly includes light
component products (gas and naphtha) and a 2 cst base oil product,
and the yields of the two products are 17.32% and 70.83%
respectively, and the diesel yield is 11.87%, indicating a bimodal
distribution of a high yield of the light component product and the
heavy component product and a low yield of the middle fraction. The
product distribution in Example 4 is similar to that in Example 3,
and the feature of bimodal distribution is more significant. The
pour points and the cloud points of the 2 cst and 6 cst base oil
products of Examples 3 and 4 are very low, and the viscosity index
of the 6 cst base oil is up to 123, which meets the requirements of
API Group III base oil.
TABLE-US-00009 TABLE 10 Properties of feed stocks of Examples 3 and
4 Analysis Item 100N Cerate 400N Cerate Density (20.degree. C.),
g/cm.sup.3 0.8319 0.8643 Kinematic Viscosity (40.degree. C.),
mm.sup.2/s 8.292 41.77 Kinematic Viscosity (100.degree. C.),
mm.sup.2/s 2.476 7.205 Viscosity Index 128 136 Pour Point, .degree.
C. 27 33 Sulfur Content, .mu.g/g 490 534 Nitrogen Content, .mu.g/g
176 430 Composition, % Saturated Hydrocarbons 90.11 83.51 Aromatic
Hydrocarbons 9.17 15.35 Polar Compounds 0.72 1.14 Distillation
Range, .degree. C. HK 307 370 5% 342 422 10% 348 450 30% 358 469
50% 367 477 70% 376 486 90% 386 498 95% 392 505 KK 404 510
TABLE-US-00010 TABLE 11 Process conditions of Examples 3 and 4
Isomerization- Asymmetrical Process Hydrorefining Cracking
Hydrofinishing Conditions Example 3 Example 4 Example 3 Example 4
Example 3 Example 4 Average 365 370 320 360 230 230 Temperature,
.degree. C. Hydrogen 13.0 13.0 12.0 12.0 12.0 12.0 Partial
Pressure, MPa Volume 1.0 1.0 0.8 0.5 1.33 0.83 Space Velocity,
h.sup.-1 Raito of 350 560 350 560 350 560 Hydrogen to Oil,
Nm.sup.3/Nm.sup.3
TABLE-US-00011 TABLE 12 Product distributions of Examples 3 and 4
Yield, % Product Example 3 Example 4 Gas + Naphtha 17.32 16.54
Diesel 11.87 5.81 2 cst Base Oil 70.81 -- 6 cst Base Oil -- 77.65
10 cst Base Oil -- -- Total Base Oil Yield 70.81 77.65
TABLE-US-00012 TABLE 13 Properties of base oil products of Examples
3 and 4 Feed stock 100N Cerate 400N Cerate Analysis Product 2 cst
base oil 6 cst base oil Method Density (20.degree. C.), 0.8340
0.8504 GB/T 1884 g/cm.sup.3 Pour Point, .degree. C. -25 -30 GB/T
3535 Cloud Point, .degree. C. -15 -19 GB/T 6986-86 Open Flash
Point, .degree. C. 176 214 GB/T 3536 Chroma, number +30 +30 GB/T
3555 Kinematic Viscosity 9.520 35.34 GB/T 265 (40.degree. C.),
mm.sup.2/s Kinematic Viscosity 2.588 6.168 GB/T 265 (100.degree.
C.), mm.sup.2/s Viscosity Index 102 123 GB/T 1995
Example 5
[0044] According to the process shown in FIG. 4, the experimental
device is the same as that in Comparative Example 1, and the feed
stock is a 650N cerate shown in Table 9, which is a waxy oil
obtained from crude oil by processes of reduced-pressure
distillation, furfural refining and acetone-toluene dewaxing, and
the physical and chemical properties. Under the process conditions
shown in Table 14, the resulting product distribution is shown in
Table 15, and the main properties of the products are shown in
Table 16.
Example 6
[0045] According to the process shown in FIG. 4, the experimental
device is the same as that in Comparative Example 1, and the feed
stock is a 150BS cerate, which is a waxy oil obtained from
paraffin-based crude oil by processes of reduced-pressure
distillation, propane deasphalting, furfural refining and
acetone--toluene dewaxing, and the physical and chemical properties
thereof are shown in Table 14. Under the process conditions shown
in Table 15, the resulting product distribution is shown in Table
16, and the main properties of the products are shown in Table
17.
[0046] It can be seen from Tables 14 to 17 that the fractions of
650SN cerate and 150BS cerate are very heavy, and the pour points
thereof are very high. With regard to the two types of heavy and
waxy feed stocks, the reduction of the pour point of the base oil
needs to be up to 78.degree. C. to achieve a pour point of base oil
of no higher than -15.degree. C. The features of high yields of
small-molecule products (gas and naphtha) and big-molecule products
(8 cst and 20 cst base oils) generated by the
hydrorefining-isomerization/asymmetrical cracking-hydrofinishing
and low yield of the middle fraction oil (diesel +2 cst base oil)
are significant. The viscosity index of the heavy product having a
low pour point is extremely high, which can be up to 140, and the
pour point and the cloud point of the heavy product can be
decreased to a very low level.
TABLE-US-00013 TABLE 14 Properties of feed stocks of Examples 5 and
6 650N 150BS Analysis Analysis Item Cerate Cerate Standard
Kinematic Density (20.degree. C.), 0.8646 0.8710 GB/T 1884
g/cm.sup.3 Kinematic Viscosity (40.degree. C.), -- -- GB/T 265
mm.sup.2/s Kinematic Viscosity (100.degree. C.), 9.359 25.10 GB/T
265 mm.sup.2/s Pour Point, .degree. C. 63 57 GB/T 3535 Sulfur
Content, .mu.g/g 690 752 ASTM D2622 Nitrogen Content, .mu.g/g 517
674 ASTM D5762 Composition, % SH/T0753 Saturated Hydrocarbons 87.65
69.1 Aromatic Hydrocarbons 11.31 23.0 Polar compounds 1.04 7.9
Simulated Distillation, .degree. C. HK 380 410 ASTM D2887 5% 480
465 10% 505 507 30% 522 562 50% 540 609 70% 551 667 90% 565 -- 95%
569 -- KK 589 --
TABLE-US-00014 TABLE 15 Process conditions of Examples 5 and 6
Isomerization- Asymmetrical Reaction Hydrorefining Cracking
Hydrofinishing Conditions Example 5 Example 6 Example 5 Example 6
Example 5 Example 6 Average 370 370 350 375 230 230 Temperature,
.degree. C. Hydrogen 14.5 14.5 14.0 14.0 14.0 14.0 Partial
Pressure, MPa Liquid hourly 0.75 0.75 0.5 0.5 1.25 1.25 Volume
Space Velocity, h.sup.-1 Raito of 750 750 750 750 750 750 Hydrogen
to Oil, Nm.sup.3/Nm.sup.3
TABLE-US-00015 TABLE 16 Product distributions of Examples 5 and 6
Yield, % Product Example 5 Example 6 Fuel Gas + Naphtha 19.31 18.76
Diesel 4.03 2.13 2 cst Base Oil 8.77 3.43 6 cst Base Oil -- 14.77 8
cst Base Oil 67.89 -- 20 cst base oil -- 60.91 Total Base Oil Yield
76.66 79.11
TABLE-US-00016 TABLE 17 Properties of heavy base oil products of
Examples 5 and 6 Feed stock 650N Cerate 150BS Cerate Analysis
Product Properties 10 cst base oil 20 cst base oil Method Density
(20.degree. C.), 0.8495 0.8542 GB/T 1884 g/cm.sup.3 Pour Point,
.degree. C. -19 -18 GB/T 3535 Cloud Point, .degree. C. -8 -6 GB/T
6986-86 Open Flash Point, .degree. C. 268 293 GB/T 3536 Chroma,
number +30 +30 GB/T 3555 Kinematic Viscosity 45.17 151.1 GB/T 265
(40.degree. C.), mm.sup.2/s Kinematic Viscosity 8.050 19.08 GB/T
265 (100.degree. C.), mm.sup.2/s Viscosity Index 152 144 GB/T
1995
Example 7
[0047] A hydrocracking UCO is a heavy fraction oil generated from a
reduced-pressure fraction oil by a hydrorefining-hydrocracking
reaction, the impurities such as sulfur and nitrogen have been
removed, and most of the aromatic hydrocarbons have been subjected
to hydrosaturation and ring-opening, such that the hydrocracking
UCO needs not to be subjected to a hydrorefining reaction to remove
sulfur and nitrogen, and needs not to be subjected to a
hydrorefining-reaction to improve the viscosity index, and the
isomerization-asymmetrical cracking/hydrofinishing shown in FIG. 6
can be adopted. Hydrogenation evaluation was performed on the
experimental device, and a hydrocracking UCO having the physical
and chemical properties shown in Table 18 was uses as a feed stock.
Under the process conditions shown in Table 19, the resulting
product distribution is shown in Table 20, and main properties of
the product are shown in Table 21. It can be seen from Tables 18 to
21 that the hydrocracking UCO has a low sulfur content and nitrogen
content, and a high viscosity index and pour point. After an
isomerization-asymmetrical cracking/hydrofinishing with mild
process conditions, the product distribution has features of high
yields of small-molecule products (gas and naphtha) and
big-molecule products (8 cst and 20 cst base oils) and low yield of
the middle fraction oil (diesel +2 cst base oil), and the cloud
point of the product achieves -15.degree. C.
TABLE-US-00017 TABLE 18 Properties of the feed stock of Example 7
Analysis Item Hydrocracking UCO Analysis Standard Kinematic Density
(20.degree. C.), 0.8245 GB/T 1884 g/cm.sup.3 Kinematic Viscosity
(40.degree. C.), 15.74 GB/T 265 mm.sup.2/s Kinematic Viscosity
(100.degree. C.), 3.824 GB/T 265 mm.sup.2/s Viscosity Index 139
GB/T 1995 Pour Point, .degree. C. 33 GB/T 3535 Sulfur Content,
.mu.g/g 2.787 ASTM D2622 Nitrogen Content, .mu.g/g 1.778 ASTM D5762
Composition, % SH/T0753 Saturated Hydrocarbons 98.75 Aromatic
Hydrocarbons 1.11 Polar Compounds 0.14 Distillation Range, .degree.
C. HK 331 ASTM D2887 5% 367 10% 375 30% 392 50% 409 70% 433 90% 473
95% 491 KK 516
TABLE-US-00018 TABLE 19 Process conditions of Example 7
Isomerization- Asymmetrical Process Conditions Cracking
Hydrofinishing Average Temperature, .degree. C. 310 230 Hydrogen
Partial Pressure, 12.4 12.4 MPa Liquid Hourly Volume Space 1.0 1.7
Velocity, h.sup.-1 Raito of Hydrogen to Oil, Nm.sup.3/Nm.sup.3 350
350
TABLE-US-00019 TABLE 20 Product distribution of Example 7 Product
Product Yield, % Fuel Gas + Naphtha 15.9 Diesel 4.66 2 cst Base Oil
1.09 4 cst Base Oil 78.35 Total Base Oil Yield 79.44
TABLE-US-00020 TABLE 21 Properties of the 4 cst base oil product of
Example 7 Analysis Item 4 cst Base Oil Analysis Method Density
(20.degree. C.), g/cm.sup.3 0.8288 GB/T 1884 Pour Point, .degree.
C. -18 GB/T 3535 Cloud Point, .degree. C. -15 GB/T 6986-86 Open
Flash Point, .degree. C. 204 GB/T 3536 Chroma, number +30 GB/T 3555
Kinematic Viscosity (40.degree. C.), 17.58 GB/T 265 mm.sup.2/s
Kinematic Viscosity (100.degree. C.), 3.974 GB/T 265 mm.sup.2/s
Viscosity Index 124 GB/T 1995
Example 8
[0048] An Fischer-Tropsch wax is a hydrocarbon product with
high-carbon-number long-chain normal paraffins as the main
component synthesized in the presence of a Co-based catalyst. The
wax mainly includes C.sub.8 to C.sub.45 normal paraffins, and the
distribution of maximum carbon number is around C.sub.18. After
cutting off components distillated at less than 320.degree. C., the
distribution of maximum carbon number of the Fischer-Tropsch wax is
slight shifted to a higher carbon number. FIG. 3 shows carbon
number distribution of a product synthesized in the presence of a
Co-based catalyst and an Fischer-Tropsch wax after cutting off
components distillated at less than 320.degree. C. by atmospheric
distillation. The Fischer-Tropsch wax substantially does not
contain impurities such as sulfur and nitrogen and aromatic
hydrocarbons, and needs not to be subjected to a hydrorefining
reaction to remove sulfur and nitrogen, and needs not to be
subjected to a hydrorefining reaction to improve the viscosity
index, and can be directly subjected to an
isomerization-asymmetrical cracking/hydrofinishing shown in FIG. 6.
The experimental device of isodewaxing is the same as that in
Comparative Example 1, the components distillated at more than
320.degree. C. in the Fischer-Tropsch wax was used as a feed stock,
of which the physical and chemical properties are shown in Table
22. Under the process conditions shown in Table 23, the resulting
product distribution is shown in Table 24, and main properties of
the product are shown in Table 25. It can be seen from Tables 22 to
25 that, the distribution of the product after the
isomerization-asymmetrical cracking/hydrofinishing has the feature
of bimodal distribution. Meanwhile, the cloud point of the 2 cst
base oil product achieves -6.degree. C., and the viscosity index is
up to 162.
TABLE-US-00021 TABLE 18 Properties of the feed stock of Example 8
Analysis Item Fischer-Tropsch wax Analysis Standard 20.degree. C.
Density, g/cm.sup.3 0.8536 GB/T 1884 100.degree. C. Viscosity,
mm.sup.2/s 4.673 GB/T 265 Pour Point, .degree. C. 59 GB/T 3535
Sulfur Content, .mu.g/g Not detected ASTM D2622 Nitrogen Content,
.mu.g/g Not detected ASTM D5762 Distillation Range, .degree. C. HK
316 ASTM D2887 5% 366 10% 375 30% 397 50% 409 70% 425 90% 495 95%
531 KK 549
TABLE-US-00022 TABLE 18 Process conditions of Example 8
Isomerization- Asymmetrical Supplementary Process Condition
Cracking Refining Average Temperature, .degree. C. 360 230 Hydrogen
Partial Pressure, 12.4 12.4 MPa Volume Space Velocity, h.sup.-1 0.5
0.85 Raito of Hydrogen to Oil, Nm.sup.3/Nm.sup.3 750 750
TABLE-US-00023 TABLE 19 Product distribution of Example 8 Product
Product Yield, % Fuel Gas + Naphtha 23.7 Diesel 6.63 2 cst Base Oil
Yield 69.67
TABLE-US-00024 TABLE 20 Properties of the product of Example 8
Product 2 cst Base Oil Analysis Method 20.degree. C. Density,
g/cm.sup.3 0.8416 GB/T 1884 Pour Point, .degree. C. -15 GB/T 3535
Cloud Point, .degree. C. -6 GB/T 6986-86 Open Flash Point, .degree.
C. 179 GB/T 3536 Chroma, number +30 GB/T 3555 40.degree. C.
Kinematic Viscosity, mm.sup.2/s 9.756 GB/T 265 100.degree. C.
Kinematic Viscosity, mm.sup.2/s 2.912 GB/T 265 Viscosity Index 162
GB/T 1995
INDUSTRIAL APPLICABILITY
[0049] In the present invention, the highly waxy heavy fraction oil
having an initial boiling point of 300.degree. C. to 460.degree.
C., a wax content of no lower than 5%, a pour point of no lower
than -20.degree. C., and a cloud point of no lower than -5.degree.
C. is used as a feed stock to produce a API (American Petroleum
Institute) Group II or Group III (see the classification standard
in Table 1) type lubricating base oil having a low pour point and a
high viscosity index by a hydrorefining-isomerization/asymmetrical
cracking-hydrofinishing three-stage hydrogenation process, wherein
a critical reaction process of hydrogenation
isomerization-asymmetrical cracking is involved. The
isomerization/asymmetrical cracking reaction include two chemical
reactions, namely, an isomerization reaction and an asymmetrical
cracking reaction. When the isomerization is carried out, the
linear paraffins having a high pour point and big-molecular and
less-branched iso-paraffins with high pour point and high viscosity
index in the feed stock are subjected to an asymmetrical cracking
reaction at the same time. The so-called asymmetrical cracking
reaction refers to a hydrocracking reaction occurs at a C--C bond
close to the two ends of the paraffin, and a big-molecule and a
small molecule are generated, wherein the small molecule belongs to
the gas and naphtha fraction, and the big-molecule belongs to the
lubricating base oil fraction.
[0050] In the asymmetrical cracking reaction, a 10-membered ring
composite molecular sieve having a special pore structure is used
as a catalyst support to enhance the restriction of the catalyst
pores on the internal diffusion of normal paraffins and
less-branched iso-paraffins, such that the cracking reaction
preferably occurs at a position close to the two ends of the normal
paraffins, thereby significantly improving the yield of the base
oil product, especially that of the heavy base oil product.
[0051] The isomerization/asymmetrical cracking reaction is
characterized in that the product has a bimodal distribution, that
is, the yields of the light components (gas and naphtha) and the
heavy base oil having a low pour point and a low cloud point are
high, and the yield of a middle fraction oil (kerosene and diesel)
is low. The method can solve the problems of low yield of target
product, high pour point and cloud point, high aromatic content and
low viscosity index and the like in the production of lubricating
base oil from heavy highly waxy oil by physical processes such as
solvent refining and solvent dewaxing and/or chemical processes
such as hydrotreating, catalytic dewaxing, hydrotreating and
hydrocracking. The process has the advantages of good adaptability
to heavy highly waxy feed stock, high yield of the heavy base oil
product with good properties such as viscosity, viscosity index,
pour point and cloud point of the product and co-production of
naphtha and a small amount of a middle fraction oil.
TABLE-US-00025 TABLE 1 API lubricating base oil Classification
standard Saturated Hydrocarbon Class Content, % Sulfur Content, %
Viscosity Index I <90 and/or >0.03 80~120 II .notlessthan.90
.notgreaterthan.0.03 80~120 III .notlessthan.90
.notgreaterthan.0.03 >120 IV poly-.alpha.-olefin (PAO) V Various
base oils except I~IV
* * * * *