JP5865907B2 - Lubricating composition - Google Patents

Description

  The present invention relates to a lubricating composition comprising a base oil and one or more additives, particularly for use in engine crankcases.

Kinematic viscosity of higher engine oil at 100 ° C. (e.g. .SAE like 2009 revised so-called SAE J300 standards January SAE xW-50 and SAE xW-60 grade stands for Society of Automotive Engineers.) to formulate, typically mineral bright stock or a heavy poly α-olefin to the formulator (heavy PAO, typically have kinematic viscosity of at 100 ° C. is 20cSt than heavy PAO)
There is an option to use.

  The problem with using a mineral brightstock that is a residual mineral base oil is that the mineral brightstock is of inherently low quality, resulting in, for example, limited oxidative stability. The problem with using heavy PAO is the inherent high cost of heavy PAO. Previous attempts have been made to solve this problem by combining a lighter distillate GTL base oil with the desired cost-effectiveness with a minimal amount of heavy PAO.

  The object of the present invention is to minimize one or more of the above problems.

  Another object of the invention is more particularly SAE 20W-50, such as SAE xW-50 and SAE xW-60 or heavier formulations, particularly for use in engine crankcases. And provide alternative lubricating compositions such as SAE 20W-60 and heavier formulations.

One or more of the above or other objects is in accordance with the present invention a lubricating composition comprising a base oil and one or more additives, wherein the base oil comprises a residual Fischer-Tropsch derived base oil, (according to ASTM D 445.) kinematic viscosity of at it is possible to obtain by providing a lubricating composition is 16.3cSt greater.

According to the present invention has now surprisingly found that a high kinematic viscosity of at 100 ° C. Suitable lubricating composition (especially engine oil) (e.g. SAE xW-50 and the like xW-60 formulation) is mineral bright stock or heavy poly It has been found that it can be formulated without the need to use alpha olefins (PAO).

  The advantage of the present invention is that the Noack volatility value (according to ASTM D 5800) of the lubricating composition is surprisingly low, in some embodiments as low as less than 3.5% by weight. is there.

  There is no particular limitation on the base oil used in the lubricating composition according to the present invention (provided that the base oil includes at least the residual Fischer-Tropsch derived base oil and the requirements for the lubricating composition according to the present invention are met), Various conventional mineral oils, synthetic oils, as well as naturally occurring esters, such as vegetable oils, can be conveniently used.

  The base oil used in the present invention may advantageously comprise a mixture of one or more mineral oils and / or one or more synthetic oils in addition to the residual Fischer-Tropsch derived base oil. Thus, according to the present invention, the term “base oil” can refer to a mixture containing one or more base oils including at least one residual Fischer-Tropsch derived base oil. Mineral oils include fluid petroleum and solvent-treated or acid-treated paraffin, naphthene or paraffin / naphthene mixed type mineral lubricants that can be further refined by hydrofinishing and / or dewaxing.

  Suitable base oils for use in the lubricating oil compositions of the present invention are derived from Group I to III mineral base oils (preferably Group III), Group IV polyalphaolefins (PAO), Group II to III Fischer-Tropsch Base oils (preferably Group III) and mixtures of these base oils.

  According to the “Group I,” “Group II,” “Group III,” and “Group IV” base oils of the present invention, the lubricant base oils of categories I, II, III and IV as defined by the American Petroleum Institute (API) Is meant. These API categories are defined in API Publication 1509, 15th Edition, Appendix E, April 2002.

  Fischer-Tropsch derived base oils are known in the art. According to the term “from Fischer-Tropsch” it is meant that the base oil is a synthetic product of the Fischer-Tropsch process or derived from a synthetic product. The Fischer-Tropsch derived base oil can also be referred to as a GTL (Gas-To-Liquids) base oil. Suitable Fischer-Tropsch derived base oils that can be conveniently used as base oils in the lubricating compositions of the present invention are, for example, EP0776959, EP0668342, WO97 / 21788, WO00 / 15736, WO00 / 14188, WO00 / 14187, WO00 / 14183. , WO 00/14179, WO 00/08115, WO 99/41332, EP 1029029, WO 01/18156 and WO 01/57166.

  Synthetic oils include hydrocarbon oils such as olefin oligomers (including poly alpha olefin base oils, PAO), dibasic acid esters, polyol esters, polyalkylene glycols (PAGs), alkylnaphthalenes and dewaxed waxes. Examples include isomers. A synthetic hydrocarbon base oil sold by the Shell Group under the name “Shell XHVI” ™ may be conveniently used.

Polyalphaolefin base oils (PAO) and the production of these oils are well known in the art. Preferred poly α-olefin base oils that may be used in the lubricating compositions of the present invention, C ₃₂ C ₂ to _linear, preferably can be derived from C ₆ to α-olefin of C _16. Particularly preferred feedstocks for the polyalphaolefins are 1-octene, 1-decene, 1-dodecene and 1-tetradecene.

  It is highly preferred to use a Fischer-Tropsch derived base oil over a PAO base oil because PAO production is costly. Thus, preferably the base oil is more than 50% by weight, preferably more than 60% by weight, more preferably more than 70% by weight, even more preferably more than 80% by weight and most preferably more than 90% by weight Fischer-Tropsch derived groups. Contains oil. In an especially preferred embodiment, less than 10% by weight of the base oil, preferably less than 5% by weight, more preferably 2% by weight or less is not a Fischer-Tropsch derived base oil.

  The lubricating composition according to the invention preferably contains less than 20% by weight of PAO base oil, preferably less than 10% by weight, more preferably less than 5% by weight, based on the total weight of the composition.

  Even more preferably, 100% by weight of the base oil is based on one or more Fischer-Tropsch derived base oils.

  The total amount of base oil incorporated in the lubricating composition of the present invention is preferably in an amount in the range of 60 to 99% by weight, more preferably in the range of 65 to 90% by weight, based on the total weight of the lubricating composition. Present in an amount, most preferably in an amount ranging from 70 to 85% by weight.

  The composition of the present invention comprises residual Fischer-Tropsch base oil. As used herein, the term “residual base oil” is a feedstock whose initial boiling point can be fixed in the heavy fraction or bottom fraction in a high vacuum column, but the final boiling point is distilled. Means the base oil determined as a result of Such final boiling point will exceed the thermal cracking temperature of the feedstock even under vacuum conditions.

  Residual Fischer-Tropsch base oil provides a viscosity grade in the same range as mineral brightstock, but because it is residual, it no longer suffers from mineral brightstock composition / performance limits. Residual Fischer-Tropsch base oil is highly paraffinic, has a low aromatic content, is highly inhibited in oxidative stability, and has the same order of viscosity as heavy PAO.

Lubricating composition according to the invention typically, (according to ASTM D445.) Kinematic viscosity of at 100 ° C. of at least 15 cSt, and preferably comprises a residual Fischer-Tropsch derived base oil is 18cSt greater. Preferably, this residual Fischer-Tropsch derived base oil has kinematic viscosity of at 100 ° C. of less than 30 cSt. Of course, the lubricating compositions according to the present invention may contain a lower kinematic viscosity of at 100 ° C., for example about 3, 5, and Fischer-Tropsch derived base oil are such 8cSt further 1 or more.

As described above, the lubricating compositions according to the present invention is kinematic viscosity of at 100 ° C. is 16.3cSt greater. Preferably, the lubricating compositions according to the present invention kinematic viscosity of at 100 ° C. is 21.9cSt greater, more preferably 23.0cSt greater. Typically, kinematic viscosity of at 100 ° C. of the lubricating composition according to the invention is less than 30.0CSt, such as less than 26.1cSt the like.

Preferably, the absolute viscosity (according to ASTM D 5293) at −15 ° C. of the lubricating composition according to the invention is less than 9500 cP (1 cP is the same as 1 mPa.s), preferably less than 8000 cP, more preferably less than 7500 cP. Even more preferably less than 7000 cP. Typically, the absolute viscosity of the lubricating composition at −15 ° C. is greater than 5000 cP , preferably greater than 6000 cP.

Preferably, the absolute viscosity (according to ASTM D 5293) at −20 ° C. of the lubricating composition according to the invention is greater than 7000 cP (1 cP is the same as 1 mPa.s), preferably greater than 8000 cP, more preferably greater than 9000 cP. , Even more preferably greater than 10,000 cP. Typically, the absolute viscosity at −20 ° C. of the lubricating composition is less than 15000 cP, preferably less than 14000 cP.

  Preferably, the high temperature high shear viscosity (“HTHS”, according to ASTM D 4683) of the lubricating composition according to the invention is greater than 3.7 cP, preferably greater than 4.5 cP, more preferably greater than 5.0 cP, or 5 Even as high as .5 or over 6.0 cP. Typically, HTHS is less than 8.0 cP.

  Typically, the Noack volatility (according to ASTM D 5800) of the lubricating composition according to the invention is between 1 and 15% by weight, preferably less than 14% by weight, more preferably less than 10.0% by weight. According to a particularly preferred embodiment according to the invention, the Noack volatility is less than 6.0% by weight, more preferably less than 5.0% by weight, or even as low as 4.0 or less than 3.5% by weight. .

  The lubricating composition according to the present invention comprises one or more additives, such as antioxidants, antiwear additives, dispersants, cleaning agents, overbased cleaning agents, extreme pressure additives, friction modifiers, viscosity index improvements. Further included are agents, pour point depressants, metal passivators, rust inhibitors, demulsifiers, antifoaming agents, seal compatibilizers and additive diluent base oils and the like.

  Those skilled in the art are familiar with these and other additives and will not be discussed in further detail here. Specific examples of such additives are described, for example, in Kirk-Othmer Encyclopedia of Chemical Technology, third edition, volume 14, pages 477-526.

  Preferably the lubricating composition according to the invention contains less than 1.0% by weight of a viscosity index improver concentrate, based on the total weight of the composition. Most preferably, the composition does not comprise a viscosity index improver concentrate.

  Preferably, the lubricating composition contains at least 0.1 wt% pour point depressant. For example, alkylated naphthalenes and phenolic polymers, polymethacrylates, maleate / fumarate copolymer esters can be advantageously used as effective pour point depressants. Preferably, a pour point depressant of 0.3% by weight or less is used.

  The lubricating composition of the present invention can be conveniently prepared by mixing one or more additives with a base oil.

  The additives described above are typically in an amount ranging from 0.01 to 35.0% by weight based on the total weight of the lubricating composition, preferably 0.05 to 25.0% by weight based on the total weight of the lubricating composition. %, More preferably in an amount ranging from 1.0 to 20.0% by weight.

  Preferably, the composition comprises at least 9.0 wt%, preferably at least 10.0 wt%, more preferably at least 11 wt% additive package comprising antiwear additives, metal detergents, ashless dispersants and antioxidants. Contains 0% by weight.

  Lubricating compositions according to the invention can be so-called “low SAPS” (SAPS = sulfate ash, phosphorus and sulfur), “medium SAPS” or “normal SAPS” formulations.

For engine oil of passenger car motor oil (PCMO), the above range is
-Sulfate ash content (according to ASTM D 874) up to 0.5% by weight, up to 0.8% by weight and up to 1.5% by weight, respectively;
-Phosphorus content (according to ASTM D 5185) up to 0.05 wt%, 0.08 wt% and typically up to 0.1 wt% respectively; and-Sulfur content (according to ASTM D 5185) respectively. It means up to 0.2 wt%, up to 0.3 wt%, and typically up to 0.5 wt%.

In the case of heavy duty diesel engine oil (Heavy Duty Diesel Engine Oil), the above range is
-Sulfate ash content (according to ASTM D 874) up to 1% by weight, up to 1% by weight and up to 2% by weight, respectively.
-Phosphorus content (according to ASTM D 5185) up to 0.08 wt% (low SAPS) and 0.12 wt% (medium SAPS), respectively;-sulfur content (according to ASTM D 5185), respectively 0.3. Up to wt% (low SAPS) and up to 0.4 wt% (medium SAPS)
Means.

  The invention is described below with reference to the following examples, which are not intended to limit the scope of the claims of the invention in any way.

Various engine oils were formulated for use in lubricating oil composition crankcase engines.

  Table 1 shows the properties of the base oils used. Table 2 shows SAE 20W-50, SAE 20W-60 and “20W-70” engine oil formulations of the complete formulations tested (SAE xW-70 grades do not yet exist. “XW-70” and “20W-70”. "Means a heavier grade than SAE xW-60 and SAE 20W-60, respectively.). Ingredient amounts are given in weight percent based on the total weight of the fully formulated formulation.

"Base oil 1" was a kinematic viscosity of at 100 ° C. (ASTM D445) is a Fischer-Tropsch derived base oil of approximately 19cSt (mm2s-1) ( "XHBO").

"Base oil 2" was a kinematic viscosity of at 100 ° C. (ASTM D445) is a Fischer-Tropsch derived base oil of approximately 17cSt (mm2s-1) ( "XHBO").

  Base oil 1 and base oil 2 can be conveniently produced, for example, by the method described in US Pat. No. 7,354,508 B2, the teachings of which are incorporated herein by reference.

"Base oil 3" kinematic viscosity of at 100 ℃ (ASTM D445) is a commercially available PAO base oil 7.83CSt. Base oil 3 is commercially available under the trade name “PAO 8” by way of example from ExxonMobil Chemicals (Brussels, Belgium).

"Base oil 4", kinematic viscosity of at 100 ℃ (ASTM D445) is a commercially available PAO base oil 40.33CSt. The base oil 4 is commercially available, for example, from ExxonMobil Chemicals (Brussels, Belgium) under the trade name “PAO 40”.

  Every tested engine oil formulation contains a combination of another base oil, an additive package, a viscosity index improver concentrate, and optionally a pour point depressant, where the additive package is all tested. In the same composition.

  The additive package contained a combination of additives including antioxidants, zinc-based anti-wear additives, ashless dispersant, base excess detergent mixture and about 10 ppm antifoam.

  Viscosity index improver concentrates were dissolved in a mixture of conventional polymer viscosity modifiers (Infineum SV-151 [styrene-hydrogenated isoprene block polymer], Shell XHVI base oil and ester base stock Infineum Additives ( Available from Milton Hill, Abingdon, UK).

  The pour point depressant is a conventional polyalkylmethacrylate (PAMA) pour point depressant and is commercially available from Evonik Rohmmax Additives GmbH (Darmstadt, Germany) under the trade name “Viscoplex® 6-054”.

  The compositions of Examples 1-7 were obtained by mixing the base oil with the additive package and pour point depressant using conventional lubricant blending techniques.

As it can be seen from consideration Table 2, in the present invention surprisingly e.g. kinematic viscosity of high lubricating composition at 100 ° C., such as engine oil (e.g. SAE xW-50, SAE xW- 60 and "xW-70" Grade)) can be formulated without the need to use mineral bright stock or heavy poly alpha olefins (PAO).

  The lubricating composition according to the present invention has a surprisingly low Noack volatility value, as low as less than 3.5% by weight.

Claims (7)

A lubricating composition comprising a base oil and one or more additives has a kinematic viscosity at 100 ° C. of greater than 21.9 cSt and less than 30.0 cSt, and an absolute viscosity at −15 ° C. (according to ASTM D 5293). ) Is a lubricating composition for crankcases of an engine having a viscosity of less than 9500 cP ,
The basis of the residual Fischer-Tropsch derived base oils include super 50% by weight in oil, the residual Fischer-Tropsch derived base oils (according to ASTM D 445.) A kinematic viscosity at 100 ° C. Ri is 16.3cSt ultra der, And less than 30 cSt,
The lubricating composition has an SAE viscosity grade of 20W-60 to 20W-70 and does not use mineral bright stock . The lubricating composition according to claim 1 , wherein the lubricating composition has an absolute viscosity at -20 ° C (according to ASTM D 5293) of greater than 7000 cP. Lubricating composition according to claim 1 or 2 , wherein the composition has a high temperature high shear viscosity ("HTHS", according to ASTM D 4683) of greater than 3.7 cP. Composition, 1 4% by weight less than Noack volatility having (by ASTM D 5800.), Lubricating composition according to any one of claims 1 to 3. Base oil, 9 0 containing by weight percent residual Fischer-Tropsch derived base oil, the lubricating composition according to any one of claims 1 to 4. Composition contains a viscosity index improver concentrate of less than 1.0 wt%, based on the total weight basis of the composition, the lubricating composition according to any one of claims 1 to 5. Lubricating composition according to any one of claims 1 to 6, wherein the pour point of the residual Fischer-Tropsch derived base oil (according to ASTM D 5950) has a temperature of less than -6 ° C.