Method for producing lubricant base oil

Abstract

A method for producing a lubricant base oil that has a predetermined boiling point range, the method including a first step of bringing a feedstock containing a first hydrocarbon oil having a boiling point in the above boiling point range and a second hydrocarbon oil having a lower boiling point than the boiling point range into contact with a hydroisomerization catalyst, wherein the catalyst contains a support that includes a zeolite having a one-dimensional porous structure including a 10-membered ring and a binder, and platinum and/or palladium supported on the support.

Claims

1. A method for producing a lubricant base oil that has a predetermined boiling point range, the method comprising: a first step of, in the presence of hydrogen, bringing a feedstock containing a first hydrocarbon oil having a boiling point in the predetermined boiling point range and a second hydrocarbon oil having a lower boiling point than the predetermined boiling point range into contact with a hydroisomerization catalyst, wherein the catalyst contains a support that includes a zeolite having a one-dimensional porous structure including a 10-membered ring and a binder, and platinum and/or palladium supported on the support, a carbon content of the catalyst is 0.4 to 3.5% by mass, a micropore volume per unit mass of the catalyst is 0.02 to 0.12 cc/g, the zeolite is derived from an ion-exchanged zeolite obtained by ion-exchanging an organic template-containing zeolite that contains an organic template and has a one-dimensional porous structure including a 10-membered ring in a solution containing ammonium ions and/or protons, and a micropore volume per unit mass of the zeolite contained in the catalyst is 0.01 to 0.12 cc/g.

2. The method according to claim 1, wherein a content of the first hydrocarbon oil in the feedstock is 5 to 60% by volume based on a total amount of feedstock.

3. The method according to claim 1, wherein the first hydrocarbon oil has a boiling point of at least 520 C. and the second hydrocarbon oil has a boiling point range of 330 C. to less than 520 C.

4. The method according to claim 1, wherein the first hydrocarbon oil has a boing point range of 470 C. to less than 520 C. and the second hydrocarbon oil has a boiling point range of 330 C. to less than 470 C.

5. The method according to claim 1, further comprising a second step of obtaining a hydrorefined oil by hydrorefining a dewaxed oil obtained in the first step, and a third step of fractionating a base oil fraction having the boiling point range from the hydrorefined oil.

Description

EXAMPLES

(1) Although the present invention will now be described more specifically based on the following Examples, the present invention is not limited to the Examples.

Production Example 1

Preparation of Hydroisomerization Catalyst A-1

(2) <Zeolite ZSM-22 Production>

(3) Zeolite ZSM-22 containing an organic template, having a Si/A1 ratio of 45, and formed from crystalline aluminosilicate was synthesized based on the following procedure. Hereinafter, zeolite ZSM-22 is referred to as ZSM-22.

(4) First, the following four types of aqueous solution were prepared.

(5) Solution A: Solution in which 1.94 g of potassium hydroxide was dissolved in 6.75 mL of ion-exchanged water.

(6) Solution B: Solution in which 1.33 g of aluminum sulfate 18-hydrate was dissolved in 5 mL of ion-exchanged water.

(7) Solution C: Solution in which 4.18 g of 1,6-hexanediamine (organic template) was diluted with 32.5 mL of ion-exchanged water.

(8) Solution D: Solution in which 18 g of colloidal silica (Ludox AS-40, manufactured by Grace Davison) was diluted with 31 mL of ion-exchanged water.

(9) Next, solution A was added into solution B, and stirring was carried out until the aluminum component was completely dissolved.

(10) Solution C was added into the mixed solution, and then while vigorously stirring at room temperature, the mixture of solutions A, B, and C was injected into solution D. In addition, as a seed crystal for promoting crystallization, 0.25 g of a separately-synthesized ZSM-22 powder that had not undergone any special treatments after being synthesized was added to the mixture to obtain a gel-like product.

(11) The gel-like product obtained by the above operation was transferred into a stainless steel autoclave reactor with an internal volume of 120 mL, and hydrothermal synthesis reaction was carried out in a 150 C. oven for 60 hours by rotating the autoclave reactor on a tumbling apparatus at a rotational speed of about 60 rpm. After the reaction was finished, the reactor was cooled, and then opened. The product was dried overnight in a 60 C. dryer to obtain ZSM-22 having a Si/Al ratio of 45.

(12) <Ion Exchange of ZSM-22 Containing an Organic Template>

(13) An ion-exchange treatment was carried out on the thus-obtained ZSM-22 with an aqueous solution containing ammonium ions by the following operation.

(14) The thus-obtained ZSM-22 was placed in a flask. 100 mL of 0.5 N aqueous ammonium chloride per 1 g of zeolite ZSM-22 was added, and the resultant mixture was heated under reflux for 6 hours. The mixture was cooled to room temperature, the supernatant was then removed, and the crystalline aluminosilicate was washed with ion-exchanged water. The same amount as above of 0.5 N aqueous ammonium chloride was again added, and the resultant mixture was heated under reflux for 12 hours.

(15) Subsequently, the solid content was collected by filtration, washed with ion-exchanged water, and dried overnight in a 60 C. dryer to obtain ion-exchanged NH.sub.4-type ZSM-22. This ZSM-22 was an ion-exchanged zeolite in a state that included an organic template.

(16) <Binder Blending, Extruding, and Calcining>

(17) The above-obtained NH.sub.4-type ZSM-22 and alumina as a binder were mixed in a mass ratio of 7:3, a small amount of ion-exchanged water was added, and the resultant mixture was kneaded. The obtained viscous fluid was loaded in an extrusion molder, and then extruded into a cylindrical extruded body having a diameter of about 1.6 mm and a length of about 10 mm. The extruded body was heated in a N.sub.2 atmosphere for 3 hours at 300 C. to obtain a support precursor.

(18) <Platinum Supporting and Calcining>

(19) An impregnation solution was obtained by dissolving tetraammineplatinum dinitrate [Pt(NH.sub.3).sub.4](NO.sub.3).sub.2 in ion-exchanged water equivalent to an amount of the water absorption of the support precursor measured in advance. This solution was impregnated into the above-described support precursor by an incipient wetness method and supporting was carried out so that the amount of platinum was 0.3% by mass based on the mass of the ZSM-22 type zeolite. Next, the obtained impregnated product (catalyst precursor) was dried overnight in a 60 C. dryer, and then calcined under an air flow for 3 hours at 400 C. to obtain a hydroisomerization catalyst A-1 containing 0.56% by mass of carbon. The carbon content was measured by combustion in oxygen gas flowinfrared absorption method. EMIA-920V manufactured by HORIBA, Ltd. was used for the measurement.

(20) In addition, the micropore volume per unit mass of the obtained hydroisomerization catalyst was calculated by the following method. First, to remove moisture adsorbed to the hydroisomerization catalyst, a pre-treatment was carried out for evacuating for 5 hours at 150 C. A nitrogen adsorption measurement was carried out on the pre-treated hydroisomerization catalyst at the temperature of liquid nitrogen (196 C.) using a BELSORP-max, manufactured by BEL Japan, Inc. Then, the micropore volume (cc/g) per unit mass of the hydroisomerization catalyst was calculated to be 0.055 by analyzing the adsorption isotherm of the measured nitrogen by a t-plot method.

(21) Further, the micropore volume V.sub.z per unit mass of the zeolite contained in the catalyst was calculated to be 0.079 based on the following expression. When the nitrogen adsorption measurement for the alumina used as a binder was carried out in the same manner as described above, it was confirmed that the alumina did not have any micropores.
V.sub.z=V.sub.c/M.sub.z100
In the expression, V.sub.c represents the micropore volume per unit mass of the hydroisomerization catalyst, and M.sub.z represents the content (% by mass) of zeolite contained in the catalyst.

Production Example 2

Preparation of Hydroisomerization Catalyst A-2

(22) Up to the step for obtaining ZSM-22, the operation was performed in the same manner as Production Example 1, and then the above-obtained ZSM-22 and alumina as a binder were mixed in a mass ratio of 7:3, a small amount of ion-exchanged water was added, and the resultant mixture was kneaded. The obtained viscous fluid was loaded in an extrusion molder, and then extruded into a cylindrical extruded body having a diameter of about 1.6 mm and a length of about 10 mm. The extruded body was heated in an air atmosphere for 3 hours at 400 C. to obtain the extruded body ZSM-22.

(23) <Ion Exchange of Extruded Body ZSM-22>

(24) An ion-exchange treatment was carried out on the thus-obtained extruded body ZSM-22 with an aqueous solution containing ammonium ions by the following operation.

(25) The thus-obtained ZSM-22 was placed in a flask. 100 mL of 0.5 N aqueous ammonium chloride per 1 g of zeolite ZSM-22 was added, and the resultant mixture was heated under reflux for 6 hours. The mixture was cooled to room temperature, the supernatant was then removed, and the crystalline aluminosilicate was washed with ion-exchanged water. The same amount as above of 0.5 N aqueous ammonium chloride was again added, and the resultant mixture was heated under reflux for 12 hours.

(26) Subsequently, the solid content was collected by filtration, washed with ion-exchanged water, and dried overnight in a 60 C. dryer to obtain ion-exchanged NH.sub.4-type ZSM-22.

(27) <Platinum Supporting and Calcining>

(28) An impregnation solution was obtained by dissolving tetraammineplatinum dinitrate [Pt(NH.sub.3).sub.4](NO.sub.3).sub.2 in ion-exchanged water equivalent to an amount of the water absorption of the support precursor measured in advance. This solution was impregnated into the above-described support precursor by an incipient wetness method and supporting was carried out so that the amount of platinum was 0.3% by mass based on the mass of the zeolite ZSM-22. Next, the obtained impregnated product (catalyst precursor) was dried overnight in a 60 C. dryer, and then calcined under an air flow for 3 hours at 400 C. to obtain a hydroisomerization catalyst A-2 containing 0.24% by mass of carbon.

(29) The micropore volume per unit mass of the hydroisomerization catalyst A-2 and the micropore volume per unit mass of the zeolite contained in the catalyst were calculated by the same method as for the hydroisomerization catalyst A-1 to be 0.132 (cc/g) and 0.189 (cc/g), respectively.

Example 1

(30) A slack wax having a boiling point range of 330 to 620 C. in which the content of the fraction having a boiling point range of 520 to 620 C. was 20% by volume was isomerized and dewaxed under conditions of an isomerization reaction temperature of 322 C., a hydrogen pressure of 15 MPa, a hydrogen/oil ratio of 500 NL/L, and a liquid hourly space velocity of 1.5 h.sup.1. For the hydroisomerization catalyst, the hydroisomerization catalyst A-1 was used. Further, the reaction temperature is a temperature at which the conversion rate was essentially 100%. In the produced oil, the content of the fraction having a boiling point range of 520 to 620 C., which is the main target fraction, was 15% by volume (the yield of this fraction in the slack wax was 80%).

Example 2

(31) A slack wax having a boiling point range of 330 to 520 C. in which the content of the fraction having a boiling point range of 470 to 520 C. was 40% by volume was isomerized and dewaxed under conditions of an isomerization reaction temperature of 325 C., a hydrogen pressure of 15 MPa, a hydrogen/oil ratio of 500 NL/L, and a liquid hourly space velocity of 1.5 For the hydroisomerization catalyst, the hydroisomerization catalyst A-1 was used. Further, the reaction temperature is a temperature at which the conversion rate was essentially 100%. In the produced oil, the yield of the fraction having a boiling point range of 470 to 520 C., which is the main target fraction, was 32% by volume (the yield of this fraction in the slack wax was 80%).

Example 3

(32) An FT synthetic wax having a boiling point range of 330 to 620 C. in which the content of the fraction having a boiling point range of 520 to 620 C. was 60% by volume was isomerized and dewaxed under conditions of an isomerization reaction temperature of 333 C., a hydrogen pressure of 15 MPa, a hydrogen/oil ratio of 500 NL/L, and a liquid hourly space velocity of 1.5 h.sup.1. For the hydroisomerization catalyst, the hydroisomerization catalyst A-1 was used. Further, the reaction temperature is a temperature at which the conversion rate was essentially 100%. In the produced oil, the yield of the fraction having a boiling point range of 520 to 620 C., which is the main target fraction, was 46% by volume (the yield of this fraction in the FT synthetic wax was 77%).

Example 4

(33) An FT synthetic wax having a boiling point range of 330 to 520 C. in which the content of the fraction having a boiling point range of 470 to 520 C. was 15% by volume was isomerized and dewaxed under conditions of an isomerization reaction temperature of 320 C., a hydrogen pressure of 15 MPa, a hydrogen/oil ratio of 500 NL/L, and a liquid hourly space velocity of 1.5 h.sup.1. For the hydroisomerization catalyst, the hydroisomerization catalyst A-1 was used. Further, the reaction temperature is a temperature at which the conversion rate was essentially 100%. In the produced oil, the yield of the fraction having a boiling point range of 470 to 520 C., which is the main target fraction, was 12% by volume (the yield of this fraction in the FT synthetic wax was 80%).

Comparative Example 1

(34) A slack wax having a boiling point range of 330 to 620 C. in which the content of the fraction having a boiling point range of 520 to 620 C. was 20% by volume was isomerized and dewaxed at an isomerization reaction temperature of 332 C., a hydrogen pressure of 15 MPa, a hydrogen/oil ratio of 500 NL/L, and a liquid hourly space velocity of 1.5 For the hydroisomerization catalyst, the hydroisomerization catalyst A-2 was used. Further, the reaction temperature is a temperature at which the conversion rate was essentially 100%. In the produced oil, the yield of the fraction having a boiling point range of 520 to 620 C., which is the main target fraction, was 13% by volume (the yield of this fraction in the slack wax was 65%).

Comparative Example 2

(35) A slack wax having a boiling point range of 330 to 520 C. in which the content of the fraction having a boiling point range of 470 to 520 C. was 40% by volume was isomerized and dewaxed at an isomerization reaction temperature of 334 C., a hydrogen pressure of 15 MPa, a hydrogen/oil ratio of 500 NL/L, and a liquid hourly space velocity of 1.5 h.sup.1. For the hydroisomerization catalyst, the hydroisomerization catalyst A-2 was used. In the product, the yield of the fraction having a boiling point range of 470 to 520 C., which is the main target fraction, was 27% by volume (the yield of this fraction in the slack wax was 68%).

Comparative Example 3

(36) A slack wax having a boiling point range of 520 to 620 C. was isomerized and dewaxed at an isomerization reaction temperature of 342 C., a hydrogen pressure of 15 MPa, a hydrogen/oil ratio of 500 NL/L, and a liquid hourly space velocity of 1.5 h.sup.1. For the hydroisomerization catalyst, the hydroisomerization catalyst A-2 was used. Further, the reaction temperature is a temperature at which the conversion rate was essentially 100%. In the produced oil, the yield of the fraction having a boiling point range of 520 to 620 C., which is the main target fraction, was 50% by volume.

Comparative Example 4

(37) A slack wax having a boiling point range of 470 to 520 C. was isomerized and dewaxed at an isomerization reaction temperature of 335 C., a hydrogen pressure of 15 MPa, a hydrogen/oil ratio of 500 NL/L, and a liquid hourly space velocity of 1.5 h.sup.1. For the hydroisomerization catalyst, the hydroisomerization catalyst A-2 was used. Further, the reaction temperature is a temperature at which the conversion rate was essentially 100%. In the produced oil, the yield of the fraction having a boiling point range of 470 to 520 C., which is the main target fraction, was 52% by volume.

Comparative Example 5

(38) An FT synthetic wax having a boiling point range of 330 to 620 C. in which the content of the fraction having a boiling point range of 520 to 620 C. was 60% by volume was isomerized and dewaxed at an isomerization reaction temperature of 342 C., a hydrogen pressure of 15 MPa, a hydrogen/oil ratio of 500 NL/L, and a liquid hourly space velocity of 1.5 h.sup.1. For the hydroisomerization catalyst, the hydroisomerization catalyst A-2 was used. Further, the reaction temperature is a temperature at which the conversion rate was essentially 100%. In the produced oil, the yield of the fraction having a boiling point range of 520 to 620 C., which is the main target fraction, was 38% by volume (the yield of this fraction in the FT synthetic wax was 63%).

Comparative Example 6

(39) An FT synthetic wax having a boiling point range of 330 to 520 C. in which the content of the fraction having a boiling point range of 470 to 520 C. was 15% by volume was isomerized and dewaxed at an isomerization reaction temperature of 328 C., a hydrogen pressure of 15 MPa, a hydrogen/oil ratio of 500 NL/L, and a liquid hourly space velocity of 1.5 h.sup.1. For the hydroisomerization catalyst, the hydroisomerization catalyst A-2 was used. In the produced oil, the yield of the fraction having a boiling point range of 470 to 520 C., which is the main target fraction, was 10% by volume (the yield of this fraction in the FT synthetic wax was 67%).

Comparative Example 7

(40) An FT synthetic wax having a boiling point range of 520 to 620 C. was isomerized and dewaxed at an isomerization reaction temperature of 345 C., a hydrogen pressure of 15 MPa, a hydrogen/oil ratio of 500 NL/L, and a liquid hourly space velocity of 1.5 h.sup.1. For the hydroisomerization catalyst, the hydroisomerization catalyst A-2 was used. Further, the reaction temperature is a temperature at which the conversion rate was essentially 100%. In the produced oil, the yield of the fraction having a boiling point range of 520 to 620 C., which is the main target fraction, was 48% by volume.

Comparative Example 8

(41) An FT synthetic wax having a boiling point range of 470 to 520 C. was isomerized and dewaxed at an isomerization reaction temperature of 330 C., a hydrogen pressure of 15 MPa, a hydrogen/oil ratio of 500 NL/L, and a liquid hourly space velocity of 1.5 h.sup.1. For the hydroisomerization catalyst, the hydroisomerization catalyst A-2 was used. Further, the reaction temperature is a temperature at which the conversion rate was essentially 100%. In the produced oil, the yield of the fraction having a boiling point range of 470 to 520 C., which is the main target fraction, was 50% by volume.

(42) It was confirmed that Examples 1 to 4, in which an isomerization and dewaxing treatment was performed on a hydrocarbon oil containing a main target fraction and a fraction that is lighter than the main target fraction using a catalyst having a predetermined nature, obtained the main target fraction at a higher yield than Comparative Examples 1 to 8, in which an isomerization and dewaxing treatment was performed without using a predetermined catalyst, or was performed on a main target fraction and a lighter fraction that had been fractionated in advance.