CN103314087A - Lubricating composition - Google Patents

Abstract

A lubricating composition comprising a base oil blend and one or more additives, wherein the base oil blend comprises: a distillate naphthenic base oil having a saturate content greater than 92% by weight as measured by IP368 and containing less than 10 ppm sulfur; and a Fischer-Tropsch derived base oil. The lubricating compositions of the present invention exhibit improved detergency and engine cleanability performance.

Description

lubricating composition

technical field

This invention relates to lubricating compositions, in particular to lubricating compositions useful as heavy duty diesel engine oils and passenger car motor oils and having improved detergency properties.

Background technique

It is to be noted that although the invention is described below with respect to lubricating compositions which are particularly useful as heavy duty diesel engine oils or passenger car motor oils, the invention is not in any way limited to these oils. The present invention can also be used as a lubricating composition for other applications, such as hydraulic fluids and turbine oils. Heavy duty diesel engine oils formulated using conventionally refined API Group II base stocks are known in the art. Unfortunately, such formulations often suffer from insufficient detergency at high temperatures. Accordingly, it would be desirable to formulate a lubricating composition, particularly for use as a heavy-duty diesel engine oil or as a passenger car motor oil, which lubricating composition has improved high temperature detergency properties and thus provides improved engine cleanliness.

Contents of the invention

According to the present invention there is provided a lubricating composition comprising a base oil blend and one or more additives, wherein the base oil blend comprises:

- a distillate naphthenic base oil having a saturates content of greater than 92% by weight and containing less than 10 ppm sulfur as measured according to IP368; and

- Fischer-Tropsch derived base oils.

It has surprisingly been found that the lubricating compositions of the present invention provide improved high temperature detergency performance.

According to another aspect of the present invention there is provided the use of a lubricating composition as described herein as a heavy duty diesel engine oil or a motor oil for passenger cars.

According to a further aspect of the present invention there is provided the use of a lubricating composition as described herein for providing improved soil release performance especially at high temperatures.

According to a further aspect of the present invention there is provided the use of a lubricating composition as described herein for providing improved engine cleanliness.

Detailed ways

The first essential component of the lubricating compositions of the present invention is the base oil blend. The base oil blend comprises a distillate naphthenic base oil and a Fischer-Tropsch derived base oil.

The naphthenic base oil used in the base oil blend is a distillate naphthenic base oil having a saturates content greater than 92 wt%, preferably greater than 95 wt%, and more preferably greater than 98 wt%, measured according to IP368. Furthermore, the naphthenic base oils used herein contain less than 10 ppm sulfur, preferably less than 5 ppm sulfur.

As used herein, the term "distillate base oil" means, either before or after the upgrading step (extraction or hydrotreatment), a high vacuum distillation separation treatment step has been carried out whereby the distillate fraction is determined by initial and final boiling points A base oil with a fixed viscosity grade.

The distillate naphthenic base oil used in the base oil blend is preferably present at a level of from 5 to 50 wt%, more preferably from 10 to 30 wt%, based on the weight of the lubricating composition.

Naphthenic base oils are distillate base oils obtained from naphthenic vacuum distillates by the following refining process: starting from naphthenic mineral crude feedstocks (typically, TAN (total acid number; ASTM D664) values greater than 0.5 mg Mineral crude feedstocks with KOH/g are naphthenic (high TAN), and less than 0.5 mg KOH/g are paraffinic (low TAN); dewaxing steps are generally not performed when making naphthenic base oils (as opposed to this In contrast, a dewaxing step is required to prepare paraffinic base oils). Optionally a dewaxing step may be employed if there are some traces of residual wax in the high TAN crude.

Preferably, the distillate naphthenic base oil used in the base oil blend has an initial boiling point (accurate boiling point according to ASTM D2887) of above 350°C, preferably above 370°C, more preferably above 500°C. Also, the distillate naphthenic base oil has an aromatic atom content _CA (according to ASTM D3238) of 2 wt% or less (typically 2 wt% or more for a paraffinic base oil).

Preferably, the distillate naphthenic base oil used in the base oil blend has a pour point below -10°C, preferably below -15°C (according to ASTM D5950).

In addition, it is preferred that the distillate naphthenic base oil used in the base oil blend has a viscosity index (according to ASTM D2270) of 90 or less, preferably 70 or less, more preferably 40 or less, even more preferably 10 or less.

Commercially available sources of distillate naphthenic base oils suitable for use in base oil blends include those available from PetroChina (Karamay) for example under the trade names "KN4006", "KN4008", "KN4010", "KN4012" , "KN4016" and "KN6025" (referred to as "K series" naphthenic base oils) are commercially available.

There is no particular limitation with respect to the Fischer-Tropsch derived base oil used in the base oil blend in the compositions of the present invention. Preferably, the Fischer-Tropsch derived base oil used in the base oil blend is a Fischer-Tropsch derived distillate base oil.

Fischer-Tropsch derived base oils are known in the art. The term "Fischer-Tropsch derived" refers to a base oil that is or is derived from a synthetic product of the Fischer-Tropsch process. Fischer-Tropsch derived base oils may also be referred to as GTL (gas-to-liquid) base oils. Suitable Fischer-Tropsch derived base oils which may conveniently be used as base oils in the functional fluid compositions of the present invention are, for example, EP0776959, EP0668342, WO97/21788, WO00/15736, WO00/14188, WO00/14187, WO00/14183 , WO00/14179, WO00/08115, WO99/41332, EP1029029, WO01/18156 and WO01/57166.

The Fischer-Tropsch derived base oil used in the base oil blend is preferably present at a level of 10-70 wt%, more preferably 20-70 wt%, even more preferably 30-65 wt%, based on the weight of the lubricating composition.

Typically, the Fischer-Tropsch derived base oil used in the present invention has a kinematic viscosity at 100°C (according to ASTM D445) of 2.0-35.0 mm ² /s, preferably 2-25.0 mm ² /s, more preferably 2.5-14 mm ² /s. According to one aspect of the present invention, it is preferred that the Fischer-Tropsch derived base oil has a kinematic viscosity at 100°C of at least 3.0 mm ² /s (according to ASTM D445), preferably at least 4.0 mm ² /s. According to another aspect of the invention, the Fischer-Tropsch derived base oil preferably has a kinematic viscosity at 100°C of at least 7.0 mm ² /s. Where the Fischer-Tropsch derived base oil comprises a blend of two or more base oils, it is preferred that the total contribution of the base oil to the kinematic viscosity is as described above (2.0-35.0 mm at 100°C according to ASTM D445 ² /s, preferably 2.0-25.0 mm ² /s, etc.).

In a preferred embodiment of the invention, the weight ratio of distillate naphthenic base oil to Fischer-Tropsch derived base oil in the base oil blend is preferably from 10:90 to 50:50, more preferably from 10:90 to 40:60, and especially 10:90-30:70.

Preferred for base oil blends (comprising distillate naphthenic base oils and Fischer-Tropsch base oils, wherein the distillate naphthenic base oils have a saturate content greater than 92 wt % and contain less than 10 ppm sulfur as measured by IP368) The pour point is less than -24°C (according to ASTM D5950), preferably less than -30°C. Also preferred are base oil blends (comprising distillate naphthenic base oils and Fischer-Tropsch base oils, wherein the distillate naphthenic base oils have a saturates content greater than 92 wt % and contain less than 10 ppm sulfur as measured by IP368) The viscosity index (according to ASTM D2270) is greater than 95, preferably greater than 100. Additionally, base oil blends (comprising distillate naphthenic base oils and Fischer-Tropsch base oils wherein the distillate naphthenic base oils have a saturate content greater than 92 wt % and contain less than 10 ppm sulfur as measured by IP368) The kinematic viscosity at 100°C is preferably 2.5-35 mm ² /s, more preferably 2.5-25 mm ² /s, even more preferably 3.5-13 mm ² /s.

In addition to the base oil blends described above, the lubricating compositions of the present invention may further comprise a mixture of one or more other mineral oils and/or one or more synthetic oils. Mineral oils include liquid petroleum and solvent-treated or acid-treated mineral lubricating oils of the paraffinic, naphthenic or mixed paraffinic/naphthenic type, which may be further refined by hydrofinishing processes and/or dewaxing .

Suitable additional base oils for use in the lubricating oil compositions of the present invention are Group I-III mineral base oils, Group IV polyalphaolefins (PAOs) and mixtures thereof.

In the present invention, "Group I", "Group II", "Group III" and "Group IV" base oils refer to base oils of classifications I, II, III and IV as defined by the American Petroleum Institute (API). Lubricant base oil. These API classifications are specified in API Publication 1509, 15th Edition, Annex E, April 2002.

Synthetic oils include hydrocarbon oils such as olefin oligomers (including polyalphaolefin base oils; PAOs), dibasic acid esters, polyol esters, polyalkylene glycols (PAGs), alkylnaphthalenes, and dewaxed waxes Isomers. The synthetic hydrocarbon base oils sold by the Shell Group under the name "Shell XHVI" (trade mark) may conveniently be used.

Preferably, the lubricating composition comprises 1-20 wt%, preferably 2-15 wt%, of naphthenic bright stock base oil, based on the total weight of the composition. A suitable naphthenic bright stock base stock is commercially available from PetroChina under the tradename HVI H150BSM, which has a kinematic viscosity (ASTM D445) of about 31 cSt at 100°C.

The total amount of base oil incorporated into the lubricating composition of the present invention (i.e. base oil blends including distillate naphthenic base oils and Fischer-Tropsch base oils and any base oils other than base oil blends , wherein the distillate naphthenic base oil has a saturate content greater than 92 wt% and contains less than 10 ppm sulfur as measured according to IP368) is preferably 50-99.9 wt%, more preferably 70-98 wt%, and most preferably 80-96 wt% %, based on the total weight of the lubricating composition.

The viscosity index (according to ASTM D2270) of the lubricating composition of the present invention is preferably 95 or more, more preferably 100 or more.

In addition, it is preferred that the composition has a total base number (TBN) (according to ASTM D4739) of 8 mgKOH/g or more and 75 mg KOH/g or less, preferably 10-70 mg KOH/g.

The lubricating composition of the present invention may further comprise one or more additives such as antioxidants, anti-wear agents, (preferably ashless) dispersants, detergents, extreme pressure additives, friction modifiers, metal deactivators, corrosion Inhibitors, demulsifiers, defoamers, seal compatibilizers and additives diluent base oil, etc.

Since the above and other additives are familiar to those skilled in the art, these are not discussed in more detail here. Specific examples of these additives are described, for example, in the Kirk-Othmer Encyclopedia of Chemical Technology, Third Edition, Volume 14, pp. 477-526.

Lubricating compositions of the invention may conveniently be prepared by admixing the one or more additives with a base oil.

The above-mentioned additives are generally present in an amount of 0.01-35.0 wt%, based on the total weight of the lubricating composition, preferably 0.05-25.0 wt%, more preferably 1.0-20.0 wt%, based on the total weight of the lubricating composition.

The lubricating composition of the present invention is preferably a heavy duty diesel engine oil or a passenger car motor oil.

In one embodiment of the present invention, the lubricating composition herein is a SAE15W-XX grade lubricating composition according to SAEJ-300, wherein XX is selected from 20, 30, 40 and 50. In preferred embodiments herein, the lubricating composition is a SAE 15W-40 grade lubricating composition according to SAE J-300.

In another embodiment of the present invention, the lubricating composition is a SAE 10W-YY grade lubricating composition according to SAE J-300, wherein YY is selected from 30 and 40.

The lubricating compositions of the present invention have improved detergency and engine cleanability properties. In particular, the lubricating composition of the present invention preferably exhibits a value of excellence greater than 7 in the Komatsu heat pipe test (Japanese Industrial Standards (JIS) - JIS Method No. JPI-5S-55-99) performed at 280°C.

In another aspect, the present invention provides the use of a lubricating composition according to the invention for improving the detergency properties, in particular according to the Komatsu heat pipe test (Japanese Industrial Standards (JIS) - JIS Method No. JPI-5S-55-99) .

The invention is illustrated below with reference to the following examples, which do not limit the scope of the invention in any way.

Example

Various lubricating compositions were formulated for use as SAE 15W-40 Heavy Duty Diesel Engine Oils (HDDEOs) (according to the so-called SAE J300 specification as revised January 2009; SAE Standard of the Society of Automotive Engineers).

Table 1 gives the properties of the base oils used. Table 2 gives the composition and properties of the fully formulated heavy duty diesel engine oils tested. The unit of component content is wt%, based on the total weight of the composition.

Except for the viscosity modifier and pour point depressant, all heavy duty diesel engine oils tested contained a combination of base oil blend and additive package (the additive package was the same in all compositions tested).

An "additive package" is a specific performance package for heavy duty diesel engine oils that contains a combination of performance additives including overbased detergents, ashless dispersants, zinc antiwear agents, antioxidants and antifoam agents.

"Base Oil 1" is a naphthenic base oil commercially available from PetroChina (Karamay, China) under the trade designation "KN4010".

"Base Oil 2" is a Fischer-Tropsch derived base oil ("GTL4") having a kinematic viscosity (ASTM D445) at 100°C of about 4 cSt (1 cSt corresponds to 1 mm ² s ⁻¹ ). GTL4 may conveniently be produced by, for example, methods described in WO02/070631, or methods analogous thereto, the teachings of which are incorporated herein by reference.

"Base oil 3" is a Chinese petroleum naphthenic bright stock named HVI H150BSM, and its kinematic viscosity (ASTM D445) at 100°C is about 31 cSt.

"Base Oil 4" is a GTL 8 cSt base oil having a kinematic viscosity (ASTM D445) at 100°C of about 8 cSt.

"Base Oil 5" is a commercially available API Group II base oil of mineral origin sold under the trade designation Motiva Star 6 by Motiva Enterprises LLC of Texas, USA.

"Base Oil 6" is a commercially available mineral source API Group II base oil sold under the trade designation Formosa 500N by Formosa Plastic Group of Mailiao Township, Taiwan.

"Base Oil 7" is a commercially available mineral source API Group II base oil sold under the trade name Formosa 150N by Formosa Plastic Group of Mailiao Township, Taiwan.

The compositions of Examples 1 and 2 and Comparative Examples 1 and 2 were obtained by blending the base oil with the additive package using conventional lubricant blending procedures.

Detergency

To demonstrate the detergent properties of the compositions of the present invention, detergent measurements (at 280°C and 290°C) were performed according to the industry standard Komatsu heat pipe test (Japanese Industrial Standards (JIS) - JIS Method No. JPI-5S-55-99) . The measured values (values of merit) are shown in Table 3 below. For tests conducted at 280°C, a figure of merit greater than 7 was considered pass, while a figure of merit of 7 or less was considered fail. For tests performed at 290°C, a figure of merit greater than 6 was considered pass, while a figure of merit of 6 or less was considered fail. Two figure of merit measurements (referred to as "value of merit 1" and "value of merit 2" in Table 3 below) were made for each example at each temperature.

In addition, each Example was also measured again for the amount of deposits according to the industry standard Komatsu heat pipe test (Japanese Industrial Standards (JIS) - JIS Method No. JPI-5S-55-99). The amount of deposits measured in each example is shown in Table 3 below.

table 3

discuss

As can be seen from Table 3, it has surprisingly been found that, in the Komatsu heat pipe test, no HDDEO compositions based on common mineral API Group II base oils (Comparative Examples 1-2, containing the same formulations as Examples 1 and 2) The HDDEO compositions of the present invention (Examples 1 and 2) have improved soil release performance compared to the same amount of additive, viscosity modifier and pour point depressant). In particular, in the Komatsu heat pipe test performed at 280°C, Example 1 had an average figure of merit of 7.3 (ie, "passed" in the test) and Example 2 had an average cleanliness figure of merit of 9.0 (ie, "passed" in the test). Pass"), while Comparative Examples 1 and 2 both had an average Cleanability Figure of Merit of 6.0 (thus "failed" in the test). In the Komatsu heat pipe test at 290°C, although Example 1 "failed" in this test, it had an average cleaning figure of merit higher than the values of Comparative Examples 1 and 2, indicating that the composition of Example 1 The detergency performance has been improved.

Regarding the deposit results, at 280°C and 290°C, the deposits of Example 2 were significantly reduced compared to Comparative Examples 1 and 2, which indicated that the detergency performance of Example 2 was improved.

Claims (15)

1. lubricating composition that comprises base oil blends and one or more additives, wherein said base oil blends comprises:

-overhead product cycloalkanes belongs to base oil, and the saturates content that it is measured according to IP368 is greater than 92wt% and comprise sulphur less than 10ppm; With

-Fisher-Tropsch derived base oil.

2. the lubricating composition of claim 1, the weight ratio that wherein said overhead product cycloalkanes belongs to base oil and described Fisher-Tropsch derived base oil is 10:90-50:50.

3. claim 1 or 2 lubricating composition, the weight ratio that wherein said overhead product cycloalkanes belongs to base oil and described Fisher-Tropsch derived base oil is 10:90-40:60.

4. each lubricating composition of claim 1-3, the weight ratio that wherein said overhead product cycloalkanes belongs to base oil and described Fisher-Tropsch derived base oil is 10:90-30:70.

5. each lubricating composition of claim 1-4, the pour point of wherein said base oil blends is less than-24 ℃ (according to ASTM D5950).

6. each lubricating composition of claim 1-5, the viscosity index of wherein said base oil blends (according to ASTM D2270) is greater than 95.

7. each lubricating composition of claim 1-6, wherein the kinematic viscosity under 100 ℃ of the base oil blends is 2.5-35mm ²/ s (according to ASTM D445).

8. the kinematic viscosity under each the lubricating composition of claim 1-7,100 ℃ of wherein said Fisher-Tropsch derived base oils is 2.5-14mm ²/ s (according to ASTM D445).

9. each lubricating composition of claim 1-8, the figure of merit in the Komatsu heat pipe test that wherein said lubricating composition is to carry out under 280 ℃ is greater than 7.

10. each lubricating composition of claim 1-9, wherein said lubricating composition is the SAE15W-XX grade lubricating composition according to SAE J-300, wherein XX is selected from 20,30,40 and 50.

11. the lubricating composition of claim 10, wherein said lubricating composition are the SAE15W-40 grade lubricating composition according to SAEJ-300.

12. each lubricating composition of claim 1-9, wherein said lubricating composition is the SAE10W-YY grade lubricating composition according to SAE J-300, and wherein YY is selected from 30 and 40.

13. each lubricating composition of claim 1-12 is as the purposes of heavy duty diesel engine oil or passenger vehicle automotive engine oil.

14. each lubricating composition of claim 1-12 is used for providing the purposes of improved de-sludging, particularly according to Komatsu heat pipe test (JIS method No.JPI-5S-55-99), particularly wherein the test of Komatsu heat pipe is carried out under 280 ℃.

15. each lubricating composition of claim 1-12 is used for providing the purposes of improved engine washing, particularly according to Komatsu heat pipe test (JIS method No.JPI-5S-55-99), particularly wherein the test of Komatsu heat pipe is carried out under 280 ℃.