Lubricating fluids for internal combustion engines fuelled with alternative combustion fuels having high auto-ignition temperatures

Abstract

A lubricating oil composition configured for lubricating an internal combustion engine fueled with an alternative fuel having an autoignition temperature above about 700K. The lubricating oil composition comprises at least a detergent system comprising at least one overbased metal sulfonate-containing detergent, optionally at least one neutral to low based metal sulfonate-containing detergent, and wherein the metals provided by the overbased sulfonate detergent are balanced relative to the total detergent metals and / or the total base number of the composition.

Description

Technical Field

[0001] This disclosure relates to a lubricating fluid for an internal combustion engine that uses an alternative combustion fuel with a high auto-ignition temperature, and a method of lubricating the internal combustion engine using the lubricating fluid when such an alternative combustion fuel is used. Background Technology

[0002] Many engine and vehicle manufacturers are exploring the use of alternative combustion fuels, such as those with high auto-ignition temperatures of around 700K or higher, as replacements for gasoline or diesel fuels. These alternative fuels include at least hydrogen, compressed natural gas (CNG), and / or liquefied natural gas (LNG). Hydrogen-fueled engines or natural gas-fueled engines offer several advantages. For example, existing internal combustion engines can often operate using these fuels with minimal modification, simplified by leveraging robust and well-understood engine platforms with a long history.

[0003] However, one challenge in the context of hydrogen or natural gas fuel engines is a problem known as stochastic pre-ignition (SPI), which is often a limiting factor in the development of hydrogen or natural gas internal combustion engines for widespread use. SPI in hydrogen or natural gas fuel engines is a premature ignition event of the main fuel supply, leading to early detonation, misfire, and / or knocking. It is similar to low-speed pre-ignition (LSPI) often found in some turbocharged direct-injection gasoline engines, but unfortunately, known solutions for improving LSPI in conventional gasoline engines do not necessarily translate to improving SPI in hydrogen or natural gas fuel engines. Summary of the Invention

[0004] In one embodiment, a lubricating oil composition is described herein, configured for lubricating an internal combustion engine fueled by fuel with an auto-ignition temperature above about 700 K. In this embodiment, the lubricating oil composition effectively reduces or minimizes random pre-ignition (SPI). The lubricating oil composition comprises one or more base oils having a lubricating viscosity; a detergent system comprising (i) at least one highly basic metal sulfonate detergent that provides about 2 mmol to about 12 mmol of metal to the composition; (ii) optionally, at least one neutral to low-basic metal sulfonate detergent that provides at least about 0.02 mmol of metal to the composition; and wherein the lubricating oil composition has a total base number (TBN) of at least about 9.5 as measured according to ASTM D2896; and wherein the percentage of metal provided by the highly basic metal sulfonate detergent is about 0.07 or less (or about 0.06 or less) of the TBN (ASTM D2896) of the lubricating oil composition.

[0005] In other methods or embodiments, the lubricating oil composition described in the preceding paragraph includes other features or embodiments in any combination. These other features or embodiments include one or more of the following: wherein the lubricating oil composition further comprises at least one highly alkaline metal-containing phenolate detergent that provides the composition with up to about 4 mmol of metal; wherein the detergent system provides only calcium metal, only magnesium metal, or (in other embodiments) a blend of calcium and magnesium; and / or wherein the lubricating oil composition is substantially free of phenolate detergents (e.g., less than 0.01 mmol of metal from phenolate detergents); and / or wherein the TBN of the lubricating oil composition is about 10 to about 15 as measured according to ASTM D2896; and / or wherein the lubricating oil composition has a TBN according to ASTM D2896. The composition contains greater than 0.9% by weight of sulfate ash (SASH) as measured by D874; and / or the lubricating oil composition contains greater than 1.2% by weight of sulfate ash (SASH) as measured according to ASTM D874; and / or the detergent system provides about 1000 ppm to about 5000 ppm of a metal selected from calcium, magnesium, or combinations thereof (preferably calcium); and / or the detergent system provides about 1500 ppm to about 3000 ppm of magnesium; and / or the composition further comprises one or more oil-soluble molybdenum compounds providing about 200 ppm or less of molybdenum; and / or the detergent system contains at least a highly alkaline magnesium sulfonate detergent having at least about 200 TBN (ASTM D2896); and / or the one or more base oils having lubricating viscosity include API Group I base oils, API Group II base oils or combinations thereof; and / or said composition is configured for lubricating an internal combustion engine fueled by fuel with an auto-ignition temperature above about 800 K; and / or said composition is configured for lubricating an internal combustion engine fueled by fuel with an auto-ignition temperature above about 850 K; and / or said lubricating oil composition has an average measured SPI of about 6 random pre-ignition (SPI) counts or less at 1000 rpm and 12 bar brake mean effective pressure (BMEP); and / or said fuel with an auto-ignition temperature above about 700 K is hydrogen fuel.

[0006] In other methods or embodiments, this disclosure also provides a method for lubricating an internal combustion engine to mitigate abnormal combustion events when using fuel with an auto-ignition temperature above about 700 K. In one aspect, the method includes lubricating the crankcase of an internal combustion engine with any embodiment of the lubricating oil composition of the present invention and burning fuel with an auto-ignition temperature above about 700 K in the internal combustion engine; and, in other embodiments, the lubricating oil composition comprises (i) one or more base oils having a lubricating viscosity and (ii) a detergent system comprising (iia) at least one highly alkaline metal sulfonate detergent that provides about 2 mmol to about 12 mmol of metal to the composition; (iib) optionally, at least one neutral to low alkaline metal sulfonate detergent that provides at least about 0.02 mmol of metal to the composition; wherein the lubricating oil composition has a total base number (TBN) of at least about 9.5 as measured according to ASTM D2896; and wherein the percentage of metal provided by the highly alkaline metal sulfonate detergent is about 0.07 or less (or about 0.06 or less) relative to the TBN (ASTM D2896) of the lubricating oil composition.

[0007] In other embodiments, the method in the preceding paragraph further includes other features, method steps, or implementations in any combination. These other features, steps, or implementations include one or more of the following: the lubricating oil composition further comprises at least one highly alkaline metal-containing phenolate detergent that provides up to about 4 mmol of metal to the composition; and / or the detergent system provides only calcium metal, only magnesium metal, or (in other embodiments) a blend of calcium and magnesium; and / or the lubricating oil composition is substantially free of phenolate detergents (e.g., less than 0.01 mmol of metal from phenolate detergents); and / or the TBN of the lubricating oil composition is about 10 to about 15 as measured according to ASTM D2896; and / or the lubricating oil composition has a sulfate ash (SASH) content greater than 0.9% by weight as measured according to ASTM D874; and / or the lubricating oil composition has a TBN content greater than 0.9% by weight as measured according to ASTM D874; and / or the lubricating oil composition has a TBN content greater than 0.9% by weight as measured according to ASTM D874. The detergent system contains greater than 1.2% by weight of sulfate ash (SASH) as measured by D874; and / or the detergent system provides about 1000 ppm to about 5000 ppm of a metal selected from calcium, magnesium, or combinations thereof; and / or the detergent system provides about 1500 ppm to about 3000 ppm of magnesium; and / or the composition further comprises one or more oil-soluble molybdenum compounds providing about 200 ppm or less of molybdenum; and / or the detergent system contains at least a highly alkaline magnesium sulfonate detergent having at least about 200 TBN (ASTM D2896); and / or the one or more base oils having a lubricating viscosity include API Group I base oils, API Group II base oils or combinations thereof; and / or said composition is configured for lubricating an internal combustion engine fueled by fuel with an auto-ignition temperature above about 800 K; and / or said composition is configured for lubricating an internal combustion engine fueled by fuel with an auto-ignition temperature above about 850 K; and / or said fuel with an auto-ignition temperature above about 700 K is hydrogen fuel, compressed natural gas or liquefied natural gas; and / or said lubricating oil composition has an average measured SPI of about 6 random pre-ignition (SPI) counts or less at 1000 rpm and 12 bar brake mean effective pressure (BMEP).

[0008] In other embodiments or methods, this disclosure also describes an internal combustion engine configured for burning hydrogen fuel, wherein the internal combustion engine includes an engine crankcase lubricated with any embodiment of the lubricating oil composition as described in the present invention, and in other embodiments, the lubricating oil composition comprises (i) one or more base oils having a lubricating viscosity and (ii) a detergent system comprising (iia) at least one highly alkaline metal sulfonate detergent that provides the composition with about 2 mmol to about 12 mmol of metal; (iib) optionally, at least one neutral to low alkaline metal sulfonate detergent that provides the composition with at least about 0.02 mmol of metal; and wherein the lubricating oil composition has a total base number (TBN) of at least about 9.5 as measured according to ASTM D2896; wherein the engine is fueled by hydrogen fuel; and wherein the percentage of metal provided by the highly alkaline metal sulfonate detergent is about 0.07 or less (or about 0.06 or less) relative to the TBN (ASTM D2896) of the lubricating oil composition.

[0009] In other embodiments or methods, the internal combustion engine of the preceding paragraph includes any combination of other features or embodiments. These other features or embodiments include one or more of the following: wherein the lubricating oil composition further comprises at least one highly alkaline metal-containing phenolate detergent that provides up to about 4 mmol of metal to the composition; and / or wherein the detergent system provides only calcium metal, only magnesium metal, or (in other embodiments) a blend of calcium and magnesium; and / or wherein the lubricating oil composition is substantially free of phenolate detergents (e.g., less than 0.01 mmol of metal from phenolate detergents); and / or wherein the TBN of the lubricating oil composition is about 10 to about 15 as measured according to ASTM D2896; and / or wherein the lubricating oil composition has a TBN of about 10 to about 15 as measured according to ASTM D2896. The composition contains greater than 0.9% by weight of sulfate ash (SASH) as measured by D874; and / or the lubricating oil composition contains greater than 1.2% by weight of sulfate ash (SASH) as measured according to ASTM D874; and / or the detergent system provides about 1000 ppm to about 5000 ppm of a metal selected from calcium, magnesium, or combinations thereof; and / or the detergent system provides about 1500 ppm to about 3000 ppm of magnesium; and / or the composition further comprises one or more oil-soluble molybdenum compounds providing about 200 ppm or less of molybdenum; and / or the detergent system contains at least a highly alkaline magnesium sulfonate detergent having at least about 200 TBN (ASTM D2896); and / or the one or more base oils having lubricating viscosity include API Group I base oils, API Group II base oils or combinations thereof; and / or said lubricating oil composition having an average measured SPI of about 6 random pre-ignition (SPI) counts or less at 1000 rpm and 12 bar brake mean effective pressure (BMEP).

[0010] In other embodiments, this document also provides for use of any embodiment of the lubricating oil composition as described in the present invention for achieving an average measured SPI of about 6 random pre-ignition (SPI) counts or less at 1000 rpm and 12 bar brake mean effective pressure (BMEP) when used in an internal combustion engine fueled by fuel with an auto-ignition temperature above about 700 K, a fuel with an auto-ignition temperature above about 800 K, or a fuel with an auto-ignition temperature above about 850 K; and / or wherein the fuel with an auto-ignition temperature above about 700 K is hydrogen fuel, compressed natural gas, or liquefied natural gas.

[0011] Other embodiments of this disclosure will be apparent to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. Attached Figure Description

[0012] Figure 1 This is a graph showing the ratio of random pre-ignition (SPI) to the percentage of metal from high-alkaline sulfonate detergents to the total base number of the lubricant (ASTM D2896). Detailed Implementation

[0013] Random pre-ignition (SPI) is a limiting factor in the widespread use of alternative combustion fuels (such as those considered in this paper, with an auto-ignition temperature of at least approximately 700 K) in internal combustion engines. While SPI is often similar to low-speed pre-ignition (LSPI) in gasoline engines, which is sometimes encountered in some turbocharged direct-injection gasoline engines, solutions to LSPI in gasoline engines do not necessarily improve SPI in engines such as hydrogen fuel cell or natural gas fuel cell internal combustion engines. Although LSPI can be mitigated by optimizing the effect of calcium in engine lubricants, this solution has little effect on improving SPI events in hydrogen fuel cell or natural gas fuel cell internal combustion engines. Therefore, conventional gasoline engine oils may not be suitable for engines operating with alternative combustion fuels, such as hydrogen fuel cell or natural gas fuel cell internal combustion engines.

[0014] According to exemplary embodiments herein, a lubricating oil composition is provided and configured for use in or otherwise configured for lubricating an internal combustion engine fueled by an alternative fuel (preferably, a fuel with an auto-ignition temperature of 850 K or higher, and most preferably, hydrogen fuel) at an auto-ignition temperature of at least about 700 K. The lubricating oil composition of this document effectively reduces SPI in engines fueled by alternative fuels. In one aspect or embodiment, the lubricating oil composition comprises one or more base oils having a lubricating viscosity; a selected detergent system comprising (i) at least one highly alkaline metal-containing sulfonate detergent providing a certain amount of metal to the lubricating composition, (ii) optionally at least one low-alkaline and / or neutral metal-containing sulfonate detergent providing a certain amount of metal to the composition, and (iii) optionally at least one highly alkaline metal-containing phenolate detergent providing a certain amount of metal to the composition; and wherein the lubricating composition has a total base number (TBN) of at least about 9.5 as measured according to ASTM D2896. As discussed below, the detergent system provides a metal selected from calcium, magnesium, or combinations thereof, and in some embodiments, the detergent system provides only calcium metal, or only magnesium metal. As shown in the examples below, when properly balanced, the amount of detergent metal from each of these detergent sources (and if included) contributes to reducing SPI. In other aspects or embodiments, the lubricating compositions herein may also have a selected relationship or ratio of the percentage of highly basic metals from the highly basic sulfonate detergent relative to the total detergent metals and relative to TBN (ASTM D2896), wherein this ratio is about 0.07 or less (or about 0.06 or less). Also as shown in the examples below, in some embodiments, this found ratio may also contribute to reducing SPI.

[0015] Higher levels of metals (such as calcium or magnesium) from high-alkalinity metal sulfonate detergents tend to adversely affect SPI in the context of hydrogen or natural gas fuel engines. However, in one embodiment, it has been found that carefully balancing the amount of metals from high-alkalinity metal sulfonate detergents with the amount of metals from optional high-alkalinity metal phenolate detergents and / or from optional low-alkalinity or neutral metal sulfonate detergents, and / or in other embodiments, carefully balancing the percentage of metals from high-alkalinity sulfonate detergents relative to total detergent metals and / or also relative to the TBN (ASTM D2896) of the finished fluid, mitigates SPI in internal combustion engines fueled by alternative combustion fuels with an auto-ignition temperature of at least about 700 K as described herein. As illustrated in the examples, lubricant compositions having the detergent system described herein achieve a reduced average SPI when the engine is fueled by alternative fuels with an auto-ignition temperature of at least about 700 K, and particularly hydrogen fuels, compressed natural gas fuels, and / or liquefied natural gas fuels, with hydrogen fuels such as gaseous hydrogen fuels being the most preferred.

[0016] Cleaning agent system

[0017] The detergent system of the lubricating oil compositions described herein comprises one or more metal-containing detergents, preferably one or more highly basic metal-containing sulfonate detergents, optionally one or more highly basic metal-containing phenolate detergents, and / or optionally one or more neutral to low-basic to neutral metal-containing sulfonate detergents. In some embodiments, the highly basic detergents described herein have a total base number (TBN) of at least about 200 (preferably about 240 to about 450 or about 250 to about 420) as measured by ASTM D2896, and the neutral to low-basic or neutral detergents have a total base number (TBN) of 50 or less as measured by ASTM D2896. Suitable detergents and methods of their preparation are described in more detail, for example, in several patent publications, including US 7,732,390; US 4,165,291 and / or US 4,206,062 (and references cited therein), which are incorporated herein by reference.

[0018] In the embodiments, a suitable detergent matrix (e.g., sulfonate or phenolate) may be salted with an alkali metal or alkaline earth metal, preferably calcium and / or magnesium. In the methods or embodiments described herein, the detergent system preferably comprises (i) at least one highly alkaline metal sulfonate detergent that provides the composition with about 2 mmol to about 12 mmol of metal (preferably about 2.5 mmol to about 7.5 mmol of metal or about 6 mmol to about 12 mmol of metal, and more preferably, the metal is calcium and / or magnesium); (ii) optionally at least one neutral to low alkaline to neutral metal sulfonate detergent that provides the composition with at least about 0.02 mmol of metal (in other methods, about 0.025 mmol to about 0.2 mmol of metal, and if included, the metal is calcium and / or magnesium); and (iii) optionally at least one highly alkaline metal phenolate detergent that provides the composition with up to about 4 mmol of metal (and if included, about 2 mmol to about 3.5 mmol of metal, and more preferably, the metal is calcium and / or magnesium) and wherein the composition has the properties specified in ASTM. The total base number (TBN) is at least about 9.5 (and preferably about 10 to about 15, and most preferably about 10 to about 14) as measured by D2896. In some embodiments, the lubricating oil compositions herein are substantially free of phenolic detergents (e.g., less than about 0.01 mmol of metal from phenolic detergents, less than about 0.005 mmol of metal from phenolic detergents, or no functional amount of phenolic detergents). In other embodiments, the detergent system herein provides about 1000 ppm to about 5000 ppm of a metal selected from calcium, magnesium, or combinations thereof; and / or in other methods or embodiments, the detergent system herein provides about 1500 ppm to about 3000 ppm of magnesium (preferably from a highly basic magnesium sulfonate detergent). In some embodiments, the detergent system contains only (i), or contains (i) and (ii), or contains (i), (ii), and (iii) and provides only calcium metal, only magnesium metal, or (in other embodiments) a blend of calcium and magnesium.

[0019] In the implementation scheme and conditioned on the discussion of the detergent system herein, suitable detergents may include straight-chain or branched alkali metal or alkaline earth metal salts of petroleum sulfonic acids and long-chain mono- or dialkylaryl sulfonic acids, such as calcium, sodium, or magnesium salts (wherein the aryl group is benzyl, tolyl, or xylyl) and / or various phenolic salts or phenolic salt derivatives. Examples of suitable detergents include (conditioned on the indicated TBN and the metal restrictions discussed herein) but are not limited to low-alkaline, neutral, and / or high-alkaline variants of the following detergents: calcium phenolate, sulfur-containing calcium phenolate, calcium sulfonate, calcium calixarate, calcium salicylate, calcium carboxylate, calcium phosphate, calcium monothiophosphate and / or calcium dithiophosphate, alkylphenol calcium, sulfur-coupled alkylphenol calcium compounds, methylene-bridged calcium phenolate, magnesium phenolate, magnesium sulfur-containing magnesium phenolate, Magnesium sulfonate, magnesium calixarelate, magnesium salicylate, magnesium carboxylate, magnesium phosphate, magnesium monothiophosphate and / or magnesium dithiophosphate, magnesium alkylphenol, magnesium thiocoupled alkylphenol compound, methylene-bridged magnesium phenolate, sodium phenolate, sodium sulfur-containing phenolate, sodium sulfonate, sodium calixarelate, sodium salicylate, sodium carboxylate, sodium phosphate, sodium monothiophosphate and / or sodium dithiophosphate, sodium alkylphenolate, sodium thiocoupled alkylphenol compound, or sodium methylene-bridged sodium phenolate. Preferably, the detergent system herein contains at least highly alkaline calcium sulfonate and / or magnesium sulfonate detergents, and highly alkaline calcium phenolate and / or magnesium phenolate detergents providing the above-mentioned metal amounts.

[0020] Highly basic metal sulfonate and phenolate detergents, as well as optionally low- to neutral metal sulfonate detergents, are well known in the art and typically comprise alkali metal or alkaline earth metal highly basic detergent additives. Such detergent additives are prepared by reacting a metal oxide or metal hydroxide with a matrix and carbon dioxide gas. The matrix is ​​typically an acid, such as, in the context of lubricants herein, an acid such as an aliphatic-substituted sulfonic acid or an aliphatic-substituted phenol.

[0021] The term "highly basic" refers to metal salts, such as the metal salts of sulfonic acids used in the fluids described herein, in which the amount of metal present exceeds the stoichiometric amount. Such salts can have conversion levels exceeding 100% (i.e., they can contain more than 100% of the theoretical amount of metal required to convert the acid to its "normal," "neutral" salt). The expression "metal ratio," often abbreviated as MR, is used to represent the ratio of the total stoichiometric amount of metal in a highly basic salt to the stoichiometric amount of metal in a neutral salt, based on known chemical reactivity and stoichiometry. In normal or neutral salts, the metal ratio is one, while in highly basic salts, MR is greater than one. These are often referred to as highly basic, hyperbasic, or superbasic salts and can be salts of organic sulfuric acids. As used herein, in one embodiment, the total base number (TBN) of the high-alkalinity detergent described herein may be about 200 mg KOH / g or greater, about 240 mg KOH / g or greater, about 250 mg KOH / g or greater, about 280 mg KOH / g or greater, or about 300 mg KOH / g or greater. As used herein, the total base number or TBN of the detergent additive is determined using ASTM D2896. When such detergent compositions are formed in an inert diluent (e.g., process oil, typically mineral oil), the total base number reflects the alkalinity of the overall composition, which includes the diluent and any other materials that may be present in the detergent composition (e.g., accelerators, etc.).

[0022] Examples of suitable high-alkalinity detergents include (subject to the TBN and metal restrictions noted herein) but are not limited to: high-alkalinity calcium phenolate, high-alkalinity phenolates containing calcium and sulfur, high-alkalinity calcium sulfonate, high-alkalinity calcium calixarate, high-alkalinity calcium salicylate, high-alkalinity calcium carboxylate, high-alkalinity calcium phosphate, high-alkalinity calcium monothiophosphate and / or calcium dithiophosphate, high-alkalinity calcium alkylphenolate, high-alkalinity calcium sulfur-coupled alkylphenolate, high-alkalinity calcium methylene-bridged phenolate, high-alkalinity magnesium phenolate, high-alkalinity magnesium sulfur-containing phenolate, high-alkalinity magnesium sulfonate, high-alkalinity magnesium calixarate, high-alkalinity magnesium salicylate, high-alkalinity magnesium carboxylate, high-alkalinity magnesium phosphate, high-alkalinity magnesium monothiophosphate and / or magnesium dithiophosphate, high-alkalinity magnesium alkylphenolate, high-alkalinity magnesium sulfur-coupled alkylphenolate, or high-alkalinity magnesium methylene-bridged phenolate.

[0023] In some embodiments, the detergent system used in the lubricant herein comprises highly basic calcium sulfonate, highly basic magnesium sulfonate, or combinations thereof, wherein each highly basic detergent has a total base number (TBN) of 200 to 450 and, in other methods, about 200 to about 425, or about 250 to about 425, or about 280 to about 425 (ASTM D2896). In other embodiments, the detergent system herein comprises optionally highly basic calcium phenolate, highly basic magnesium phenolate, or combinations thereof, each having a total base number of 200 to 450 and, in other methods, about 200 to about 400, or about 225 to about 350, or about 240 to about 300 (ASTM D2896). In other embodiments, the detergent system described herein may also include optional low-alkaline to neutral calcium sulfonate, low-alkaline to neutral magnesium sulfonate, or combinations thereof, each having a total base number (TBN) of 50 or less and, in other methods, about 0 to about 50, about 0 to about 40, or about 0 to about 30 (ASTM D2896). The above TBN values ​​reflect the values ​​of the finished detergent components diluted in the base oil.

[0024] Unwilling to be limited by theory, lubricants with higher contents of high-alkaline sulfonate detergents tend to exhibit higher levels of undesirable SPI events when used to lubricate engines operating on alternative combustion fuels described herein (e.g., fuels with an auto-ignition temperature of at least about 700 K, such as hydrogen or natural gas). However, acceptable SPI levels can be achieved when the metals provided by the high-alkaline sulfonate detergent content are properly balanced relative to the total detergent metals and / or when the percentage of metals from the high-alkaline sulfonate detergent is balanced relative to the lubricant TBN (ASTM D2896). Figure 1 As shown in the examples below, for example, when the weight percentage of metal from the high-alkalinity sulfonate detergent is about 0.07 or less of the TBN (ASTM D2896) of the lubricant, and in other embodiments, about 0.06 or less, about 0.055 or less, or about 0.01 to about 0.07, about 0.01 to about 0.06, or about 0.02 to about 0.055 (or any other range therein), the average SPI events are less than 6 average SPI events per 1000 cycles, and in other embodiments, 2 to 6 average SPI events per 1000 cycles. As explained in the Examples section below, SPI can be evaluated at FEVEurope GmbH or other suitable testing facilities using, for example, a 6-cylinder engine modified (as needed) to operate at 1000 rpm and 12 bar brake mean effective pressure (BMEP) using alternative fuels (e.g., those with an auto-ignition temperature of at least 700 K, such as hydrogen, compressed natural gas, or liquefied natural gas). Figure 1As shown in the examples, when the percentage of metals provided by the high-alkalinity sulfonate detergent (e.g., the number of mmol of metals from the high-alkalinity sulfonate detergent divided by the total number of mmol of metals from the detergent) is too high relative to the TBN of the detergent, the SPI events increase to an undesirable level (typically an average of 6 or more SPI events).

[0025] Lubricating oil composition

[0026] The lubricating oil compositions described herein comprise the aforementioned detergent system and other additives suitable for lubricating internal combustion engines when using alternative combustion fuels having the indicated autoignition temperatures. In one method, the total base number of the lubricating composition described herein, as measured according to ASTM D2896, is at least about 9.5; in other embodiments, it is about 10 to about 15; and in yet another embodiment, it is about 10 to about 14. As noted above, the TBN can be balanced relative to the percentage of metals provided by the highly basic sulfonate detergent to mitigate SPI, with a desired ratio of about 0.07 or less, as shown in the examples.

[0027] In some embodiments, the lubricating oil compositions herein may also have a high level of sulfate ash content, as measured by ASTM D874. For example, and in embodiments, the lubricating oil compositions herein have a sulfate ash (SASH) content greater than about 0.9 wt%, greater than about 1.0 wt%, greater than about 1.1 wt%, greater than about 1.2 wt%, greater than about 1.3 wt%, greater than about 1.4 wt%, or greater than about 1.5 wt%. In other embodiments, the lubricating oil compositions herein may have a sulfate ash (SASH) content of up to about 1.0 wt%, or up to about 1.6 wt%, or about 1.0 wt% to about 1.6 wt%, or about 1.2 wt% to about 1.6 wt%, as measured by ASTM D874.

[0028] base oil :

[0029] The lubricating fluids described herein comprise one or more base oils having a lubricating viscosity. Base oils suitable for formulating the lubricating oil compositions used herein for lubricating internal combustion engines fueled by alternative fuels as described herein may be selected from any suitable synthetic oil or natural oil, or mixtures thereof, having a suitable lubricating viscosity. Natural oils may include animal and vegetable oils (e.g., castor oil, lard) and mineral oils, such as liquid petroleum and solvent-treated or acid-treated alkanes, naphthenes, or mixed alkanes-naphthenes. Oils derived from coal or shale may also be suitable. Furthermore, oils derived from gas-to-liquid processes are also suitable. As measured by ASTM D2270-10, the base oil may have a kinematic viscosity of about 2 cSt to about 15 cSt at 100°C (e.g., kV100).

[0030] The base oils used in this invention can be a single base oil or a mixture of two or more base oils. In one embodiment, the one or more base oils can be selected from any of the Group I to Group IV base oils specified in the American Petroleum Institute (API) Base Oil Interchangeability Guide. In other embodiments, the one or more base oils having lubricating viscosity preferably include only API Group I base oils, API Group II base oils, or combinations thereof. These base oil categories are shown in Table 1 below:

[0031] Table 1

[0032]

[0033] API Group III base oils may include oils derived from Fischer-Tropsch synthetic hydrocarbons. Fischer-Tropsch synthetic hydrocarbons are prepared from syngas containing H2 and CO using a Fischer-Tropsch catalyst. These hydrocarbons typically require further processing before use as base oils. These types of oils are commonly referred to as gas-to-liquid (GTL) oils. For example, the hydrocarbons can be hydroisomerized using the methods disclosed in U.S. Patent 6,103,099 or 6,180,575; hydrocracking and hydroisomerized using the methods disclosed in U.S. Patent 4,943,672 or 6,096,940; dewaxing using the methods disclosed in U.S. Patent 5,882,505; or hydroisomerized and dewaxing using the methods disclosed in U.S. Patent 6,013,171, 6,080,301; or 6,165,949.

[0034] API Group IV base oils, PAOs, are typically derived from monomers having 4 to 30, 4 to 20, or 6 to 16 carbon atoms. Examples of PAOs that can be used in this invention include those derived from octene, decene, mixtures thereof, etc. As measured by ASTM D2270-10, PAOs can have a kinematic viscosity of 2 cSt to 15 cSt, 3 cSt to 12 cSt, or 4 cSt to 8 cSt at 100°C. Examples of PAOs include PAOs with a viscosity of 4 cSt at 100°C, PAOs with a viscosity of 6 cSt at 100°C, and mixtures thereof.

[0035] A base oil is combined with an additive composition as disclosed in the embodiments herein to provide a lubricating oil composition for lubricating the crankcase of an internal combustion engine fueled by a gaseous fuel with an auto-ignition temperature above about 700 K. Therefore, the base oil may be present in the lubricating oil composition in an amount greater than about 80% by weight, based on the total weight of the lubricating oil composition. In some embodiments, the base oil may be present in the lubricating oil composition in an amount greater than about 85% by weight, based on the total weight of the lubricating oil composition.

[0036] Alternative fuels

[0037] The lubricating oil compositions described herein are configured for lubricating the crankcase of an internal combustion engine fueled by an alternative combustion fuel. For the purposes of this disclosure, the alternative combustion fuel is a fuel with an auto-ignition temperature of at least about 700 K, at least about 800 K, or at least about 850 K. In other cases, the alternative combustion fuel has an auto-ignition temperature as high as about 900 K, as high as about 880 K, or as high as about 860 K. Such alternative combustion fuels include, but are not limited to, hydrogen fuel (auto-ignition temperature of about 858 K), which may be gaseous hydrogen fuel, and natural gas fuel (auto-ignition temperature of about 813 K), which may be compressed natural gas and / or liquefied natural gas. Preferably, the alternative combustion fuel suitable for use in the lubricating compositions described herein includes gaseous hydrogen fuel that burns in a gaseous state in the engine.

[0038] Other additives

[0039] In addition to the components described above, the lubricating oil compositions described herein may also contain other types of additives for use in crankcase lubrication compositions. Such additives include, but are not limited to, antioxidants, viscosity modifiers, phosphorus-containing components, detergents, corrosion inhibitors, rust inhibitors, defoamers, demulsifiers, pour point depressants, sealing swelling agents, and additional dispersants, additional friction modifiers, and additional sulfur-containing components.

[0040] dispersantLubricating oil compositions may optionally contain one or more dispersants or mixtures thereof. Dispersants are generally referred to as ashless dispersants because they do not contain ash-forming metals before being incorporated into the lubricating oil composition and typically do not provide any ash when added to the lubricant. Ashless dispersants are characterized by polar groups attached to relatively high molecular weight hydrocarbon chains. Typical ashless dispersants include N-substituted long-chain alkenyl succinimides. Examples of N-substituted long-chain alkenyl succinimides include polyisobutylene succinimides, wherein, as measured by GPC, the number average molecular weight of the polyisobutylene substituent is in the range of about 350 to about 50,000, or about 5,000, or about 3,000. Succinimid dispersants and their preparation are disclosed, for example, in U.S. Patent No. 7,897,696 or U.S. Patent No. 4,234,435. The alkenyl substituent may be prepared from polymerizable monomers containing about 2 to about 16, about 2 to about 8, or about 2 to about 6 carbon atoms. Succinimide dispersants are typically composed of polyamines, usually poly(ethylene amine) imides.

[0041] Preferred amines are selected from polyamines and hydroxylamines. Examples of polyamines that may be used include, but are not limited to, diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), and higher homologues such as pentaethylenehexamine (PEHA).

[0042] Suitable heavy polyamines are mixtures of polyalkylene polyamines containing small amounts of lower polyamine oligomers (such as TEPA and PEHA (pentaethylenehexamine)) but primarily having 6 or more nitrogen atoms per molecule, 2 or more primary amines, and oligomers with more extensive branching than conventional polyamine mixtures. Heavy polyamines preferably comprise polyamine oligomers containing 7 or more nitrogen atoms per molecule and 2 or more primary amines per molecule. Heavy polyamines contain greater than 28% by weight (e.g., >32% by weight) of total nitrogen and 120 g / equivalent to 160 g / equivalent of primary amine groups by equivalent weight.

[0043] In some methods, the appropriate polyamine is often referred to as PAM and contains a mixture of ethylenediamines, in which TEPA and pentaethylenehexamine (PEHA) are the main components of the polyamine, typically less than about 80%.

[0044] Typically, PAM contains 8.7–8.9 milliequivalents of primary amine per gram (equivalent to 115–112 grams per gram of primary amine) and approximately 33–34 wt% of total nitrogen. Heavier PAM oligomers have almost no TEPA, only very small amounts of PEHA, but mainly contain more than 6 nitrogen atoms and more extensively branched oligomers, allowing for the production of dispersants with improved dispersibility.

[0045] In one embodiment, this disclosure further comprises at least one polyisobutylene succinimide dispersant derived from polyisobutylene with a number average molecular weight in the range of about 350 to about 50,000, about 5,000, or about 3,000, as determined by GPC. The polyisobutylene succinimide may be used alone or in combination with other dispersants.

[0046] In some embodiments, polyisobutylene (when included) may have terminal double bonds in amounts greater than 50 mol%, greater than 60 mol%, greater than 70 mol%, greater than 80 mol%, or greater than 90 mol%. Such PIBs are also referred to as highly reactive PIBs (“HR-PIBs”). HR-PIBs with a number-average molecular weight in the range of about 800 to about 5000, as determined by GPC, are suitable for embodiments of this disclosure. Conventional PIBs typically have terminal double bonds in amounts less than 50 mol%, less than 40 mol%, less than 30 mol%, less than 20 mol%, or less than 10 mol%.

[0047] HR-PIBs with a number-average molecular weight in the range of about 900 to about 3000, as determined by GPC, are suitable. Such HR-PIBs are commercially available or can be synthesized by polymerizing isobutylene in the presence of a non-chlorinated catalyst, such as boron trifluoride, as described in U.S. Patent No. 4,152,499 to Boerzel et al. and U.S. Patent No. 5,739,355 to Gateau et al. When used in the aforementioned thermo-olefin reaction, HR-PIBs can increase the conversion rate in the reaction and reduce the amount of sediment formation due to enhanced reactivity. Suitable methods are described in U.S. Patent No. 7,897,696.

[0048] In one embodiment, this disclosure also includes at least one dispersant derived from polyisobutylene succinic anhydride (“PIBSA”). PIBSA may have an average succinic moiety of about 1.0 to about 2.0 per polymer. Chromatographic techniques can be used to determine the activity % of the alkenyl or alkyl succinic anhydride. This method is described in columns 5 and 6 of U.S. Patent 5,334,321. The conversion percentage of the polyolefin is calculated from the activity % using the equations in columns 5 and 6 of U.S. Patent 5,334,321. Unless otherwise stated, all percentages are weight percentages (wt%), and all molecular weights are number average molecular weights determined by gel permeation chromatography (GPC) using commercially available polystyrene standards (with a number average molecular weight of 180 to about 18,000 as a calibration reference).

[0049] In one embodiment, the dispersant may be derived from polyalphaolefin (PAO) succinic anhydride. In another embodiment, the dispersant may be derived from an olefin maleic anhydride copolymer. For example, the dispersant may be described as polyPIBSA. In one embodiment, the dispersant may be derived from an anhydride grafted onto an ethylene-propylene copolymer.

[0050] Suitable classes of nitrogen-containing dispersants may be derived from olefin copolymers (OCPs), more specifically, ethylene-propylene dispersants, which may be grafted with maleic anhydride. A more complete list of nitrogen-containing compounds that can react with functionalized OCPs is described in U.S. Patent Nos. 7,485,603; 7,786,057; 7,253,231; 6,107,257; and 5,075,383; and / or are commercially available.

[0051] Another suitable class of dispersants is the Mannich base. Mannich bases are substances formed by the condensation of alkyl-substituted phenols, polyalkylene polyamines, and aldehydes (such as formaldehyde) with higher molecular weight alkyl groups. Mannich bases are described in more detail in U.S. Patent No. 3,634,515.

[0052] Suitable dispersants can also be high molecular weight esters or hemiesteramides. Suitable dispersants can also be post-treated by conventional methods through reaction with any of a variety of reagents. These include boron, urea, thiourea, dimercaptothiadiazole, carbon disulfide, aldehydes, ketones, carboxylic acids, hydrocarbon-substituted succinic anhydrides, maleic anhydrides, nitriles, epoxides, carbonates, cyclic carbonates, hindered phenolic esters, and phosphorus compounds. US 7,645,726; US 7,214,649; and US 8,048,831 are incorporated herein by reference in their entirety.

[0053] In addition to carbonate and boric acid posttreatments, both compounds can be posttreated or further posttreated using a variety of posttreatment methods designed to improve or impart different properties. Such posttreatments include those outlined in columns 27 through 29 of U.S. Patent No. 5,241,003, which are incorporated herein by reference. Such treatments include treatments with: inorganic phosphorous acid or anhydrous substances (e.g., U.S. Patent Nos. 3,403,102 and 4,648,980); organophosphorus compounds (e.g., U.S. Patent No. 3,502,677); phosphorus pentasulfide; boron compounds as described above (e.g., U.S. Patent Nos. 3,178,663 and 4,652,387); carboxylic acids, polycarboxylic acids, acid anhydrides, and / or acidic halides (e.g., U.S. Patent Nos. 3,708,522 and 4,948, ...). 386); epoxides, polyepoxides, or thioepoxides (e.g., U.S. Patent Nos. 3,859,318 and 5,026,495); aldehydes or ketones (e.g., U.S. Patent No. 3,458,530); carbon disulfide (e.g., U.S. Patent No. 3,256,185); glycidyl (e.g., U.S. Patent No. 4,617,137); urea, thiourea, or guanidine (e.g., U.S. Patent Nos. 3,312,619; 3,865,813; and British Patent GB 1,065,595); organic sulfonic acids (e.g., U.S. Patent No. 3,189,544 and British Patent GB 1,065,595). 2,140,811); alkenyl cyanides (e.g., U.S. Patent Nos. 3,278,550 and 3,366,569); dienoketones (e.g., U.S. Patent No. 3,546,243); diisocyanates (e.g., U.S. Patent No. 3,573,205); alkane sulcolides (e.g., U.S. Patent No. 3,749,695); 1,3-dicarbonyl compounds (e.g., U.S. Patent No. 4,579,675); sulfates of alkoxylated alcohols or phenols (e.g., U.S. Patent No. 3,954,6... 39); cyclic lactones (e.g., U.S. Patent Nos. 4,617,138; 4,645,515; 4,668,246; 4,963,275; and 4,971,711); cyclic carbonates or thiocarbonates, linear monocarbonates or polycarbonates, or chloroformates (e.g., U.S. Patent Nos. 4,612,132; 4,647,390; 4,648,886; 4,670,170); nitrogen-containing carboxylic acids (e.g., U.S. Patent No. 4,971,598 and British Patent GB). 2,140,811); hydroxyl-protected chlorodicarbonyloxy compounds (e.g., U.S. Patent No. 4,614,522); lactams, thiolactams, thiolactones, or dithiolactones (e.g., U.S. Patent Nos. 4,614,603 and 4,666,460); cyclic carbonates or thiocarbonates, linear monocarbonates or polycarbonates, or chloroformates (e.g., U.S. Patent Nos. 4,612,132; 4,647,390; 4,646,860; and 4,670,170);Nitrogen-containing carboxylic acids (e.g., U.S. Patent No. 4,971,598 and British Patent GB 2,440,811); hydroxyl-protected chlorodicarbonyloxy compounds (e.g., U.S. Patent No. 4,614,522); lactams, thiolactams, thiolactones, or dithiolactones (e.g., U.S. Patent Nos. 4,614,603 and 4,666,460); cyclic carbamates, cyclic thiocarbamates, or cyclic dithiocarbamates (e.g., U.S. Patent Nos. 4,663,062 and 4,666,459); hydroxy aliphatic carboxylic acids (e.g., U.S. Patent Nos. 4,482,464; 4,521,318; 4,713,189); oxidizing agents (e.g.) For example, U.S. Patent No. 4,379,064; combinations of phosphorus pentasulfide and polyalkylene polyamines (e.g., U.S. Patent No. 3,185,647); combinations of carboxylic acids or aldehydes or ketones and sulfur or sulfur chloride (e.g., U.S. Patent Nos. 3,390,086; 3,470,098); combinations of hydrazine and carbon disulfide (e.g., U.S. Patent No. 3,519,564); combinations of aldehydes and phenols (e.g., U.S. Patent Nos. 3,649,229; 5,030,249; 5,039,307); combinations of aldehydes and O-diesters of dithiophosphates (e.g., U.S. Patent No. 3,865). ,740); combinations of hydroxyaliphatic carboxylic acids and boric acid (e.g., U.S. Patent No. 4,554,086); combinations of hydroxyaliphatic carboxylic acids, then formaldehyde and phenol (e.g., U.S. Patent No. 4,636,322); combinations of hydroxyaliphatic carboxylic acids and then aliphatic dicarboxylic acids (e.g., U.S. Patent No. 4,663,064); combinations of formaldehyde and phenol and then glycolic acid (e.g., U.S. Patent No. 4,699,724); combinations of hydroxyaliphatic carboxylic acids or oxalic acid, and then diisocyanates (e.g., U.S. Patent No. 4,713,191); inorganic acids or anhydrides of phosphorus or parts thereof. Combinations of sulfur analogues or all of them with boron compounds (e.g., U.S. Patent No. 4,857,214); combinations of organic diacids, then unsaturated fatty acids, then nitrosoaromatic amines, optionally followed by boron compounds, and then ethanolating agents (e.g., U.S. Patent No. 4,973,412); combinations of aldehydes and triazoles (e.g., U.S. Patent No. 4,963,278); combinations of aldehydes and triazoles, then boron compounds (e.g., U.S. Patent No. 4,981,492); combinations of cyclic lactones and boron compounds (e.g., U.S. Patent Nos. 4,963,275 and 4,971,711). The patents mentioned above are incorporated herein by reference in their entirety.

[0054] The TBN of a suitable dispersant can be from about 10 mg KOH / g to about 65 mg KOH / g dispersant on an oil-free basis, or from about 5 TBN to about 30 TBN if measured on a dispersant sample containing about 50% diluent oil. TBN is measured according to the method of ASTM D2896.

[0055] In other embodiments, the optional dispersant additive may be a hydrocarbon-substituted succinamide or succinimide dispersant. In the method, the hydrocarbon-substituted succinamide or succinimide dispersant is derived from a hydrocarbon-substituted acylated agent reacting with a polyalkylene polyamine, and wherein, as measured by GPC using polystyrene as a calibration reference, the hydrocarbon substituent of the succinamide or succinimide dispersant is a linear or branched hydrocarbon group with a number average molecular weight of about 250 to about 5,000.

[0056] In some methods, the polyalkylene polyamine used to form the dispersant has the formula...

[0057]

[0058] Each R and R' is independently a divalent C1 to C6 alkylene linking group, each R1 and R2 is independently a hydrogen, a C1 to C6 alkyl group, or, together with the nitrogen atom to which they are linked, a 5-membered or 6-membered ring optionally fused with one or more aromatic or non-aromatic rings, and n is an integer between 0 and 8. In other methods, the polyalkylene polyamine is selected from the group consisting of: mixtures of polyethylene polyamines having an average of 5 to 7 nitrogen atoms, triethylenetetramine, tetraethylenepentamine, and combinations thereof.

[0059] If a dispersant is present, it may be sufficient to provide up to about 20% by weight for use, based on the final weight of the lubricating oil composition. Another amount of dispersant that may be used, based on the final weight of the lubricating oil composition, may be about 0.1% to about 15% by weight, or about 0.1% to about 10% by weight, or about 0.1% to about 8% by weight, or about 1% to about 10% by weight, or about 1% to about 8% by weight, or about 1% to about 6% by weight. In some embodiments, the lubricating oil composition utilizes a mixed dispersant system. A single type of dispersant or a mixture of two or more types of dispersants may be used in any desired ratio.

[0060] anti-wear agentThe lubricating oil compositions described herein may optionally contain one or more anti-wear agents. Examples of suitable anti-wear agents include, but are not limited to, metal thiophosphates; metal dialkyl dithiophosphates; phosphate esters or salts thereof; phosphate esters; phosphites; phosphoric acid esters, ethers or amides; sulfurized olefins; compounds containing thiocarbamates, including thiocarbamates, alkylene-coupled thiocarbamates, dithiocarbamates and / or bis(S-alkyldithiocarbamoyl) disulfides; and mixtures thereof. Suitable anti-wear agents may be molybdenum dithiocarbamate, bis(dialkyl-dithiocarbamate) or alkylene-bis(dialkyl-dithiocarbamate), etc. Phosphorus-containing anti-wear agents are described more fully in European Patent 612 839. The metal in the dialkyldithiophosphate may be an alkali metal, an alkaline earth metal, aluminum, lead, tin, molybdenum, manganese, nickel, copper, titanium or zinc. A suitable anti-wear agent may be zinc dialkyldithiophosphate.

[0061] Other examples of suitable anti-wear agents include titanium compounds, tartrates, tartrate imides, oil-soluble amine salts of phosphorus compounds, sulfurized olefins, phosphites (such as dibutyl phosphite), phosphonates, and compounds containing thiocarbamates (such as thiocarbamates, thiocarbamate amides, thiocarbamate ethers, alkylene-coupled thiocarbamates, and bis(S-alkyldithiocarbamoyl) disulfides). Tartrates or tartrate imides may contain alkyl ester groups, wherein the total number of carbon atoms in the alkyl groups may be at least 8. In one embodiment, the anti-wear agent may include citrates.

[0062] The anti-wear agent may be present in the range of about 0% to about 15% by weight, or about 0.01% to about 10% by weight, or about 0.05% to about 5% by weight, or about 0.1% to about 3% by weight of the lubricating oil composition. In other embodiments, the composition herein may also contain one or more oil-soluble molybdenum compounds, and if contained, provide about 200 ppm or less of molybdenum, less than about 150 ppm, less than about 100 ppm, or less than about 50 ppm of molybdenum.

[0063] antioxidants In some embodiments, the lubricating oil compositions described herein may contain one or more antioxidants. Suitable antioxidants include phenolic antioxidants, aromatic amine antioxidants, sulfur-containing antioxidants, and organophosphites, etc.

[0064] Examples of phenolic antioxidants include 2,6-di-tert-butylphenol, liquid mixtures of tert-butylphenol, 2,6-di-tert-butyl-4-cresol, 4,4'-methylenebis(2,6-di-tert-butylphenol), 2,2'-methylenebis(4-methyl-6-tert-butylphenol), and mixtures of methylene-bridged polyalkylphenols and 4,4'-thiobis(2-methyl-6-tert-butylphenol), N,N'-di-sec-butylphenylenediamine, 4-isopropylaminodiphenylamine, benzene-α-naphthylamine, benzene-α-naphthylamine, and cycloalkylated diphenylamines. Examples include sterically hindered tert-butylated phenols, bisphenols, and cinnamic acid derivatives, and combinations thereof.

[0065] Aromatic amine antioxidants include, but are not limited to, diarylamines having the following formula:

[0066]

[0067] R' and R'' each independently represent a substituted or unsubstituted aryl group having 6 to 30 carbon atoms. Examples of substituents for aryl groups include aliphatic hydrocarbon groups such as alkyl, hydroxyl, halogen, carboxylic, ester, or nitro groups having 1 to 30 carbon atoms.

[0068] The aryl group is preferably a substituted or unsubstituted phenyl or naphthyl group, particularly wherein one or both of these aryl groups are substituted with at least one alkyl group having 4 to 30 carbon atoms, preferably 4 to 18 carbon atoms, and most preferably 4 to 9 carbon atoms. It is preferred that one or both aryl groups are substituted, for example, monoalkylated diphenylamine, dialkylated diphenylamine, or a mixture of monoalkylated diphenylamine and dialkylated diphenylamine.

[0069] Examples of diarylamines that may be used include, but are not limited to: diphenylamine; various alkylated diphenylamines, 3-hydroxydiphenylamine, N-phenyl-1,2-phenylenediamine, N-phenyl-1,4-phenylenediamine, monobutyldiphenylamine, dibutyldiphenylamine, monooctyldiphenylamine, dioctyldiphenylamine, monononyldiphenylamine, dinonyldiphenylamine, monotetradecyldiphenylamine, tetradecyldiphenylamine, benzene-α-naphthylamine, monooctylphenyl-α-naphthylamine, benzene-β-naphthylamine, monoheptyldiphenylamine, diheptyldiphenylamine, p-oriented styrylated diphenylamine, mixed butyloctyldiphenylamine and mixed octylstyryldiphenylamine.

[0070] Sulfur-containing antioxidants include, but are not limited to, sulfurized olefins, characterized by the type of olefin used in their production and the final sulfur content of the antioxidant. High molecular weight olefins (i.e., those with an average molecular weight of 168 g / mol to 351 g / mol) are preferred. Examples of olefins that can be used include α-olefins, isomerized α-olefins, branched olefins, cycloolefins, and combinations thereof.

[0071] α-olefins include, but are not limited to, any C4 to C5 olefins.25 α-Alkenes. α-Alkenes can be isomerized before or during sulfidation. Structural and / or conformational isomers of α-alkenes containing internal double bonds and / or branches can also be used. For example, isobutene is a branched alkene counterpart of the α-alkene 1-butene.

[0072] Sulfur sources that can be used in olefin sulfidation reactions include elemental sulfur, sulfur monochloride, sulfur dichloride, sodium sulfide, sodium polysulfide, and mixtures thereof, either together or added at different stages of the sulfidation process.

[0073] Unsaturated oils, due to their unsaturation, can also be sulfurized and used as antioxidants. Examples of oils or fats that can be used include corn oil, canola oil, cottonseed oil, grapeseed oil, olive oil, palm oil, peanut oil, coconut oil, rapeseed oil, safflower oil, sesame oil, soybean oil, sunflower oil, tallow, and combinations thereof.

[0074] The total amount of antioxidant in the lubricating oil composition described herein may be present in an amount delivering up to about 200 ppm of nitrogen or up to about 150 ppm of nitrogen or about 100 ppm to about 150 ppm of nitrogen.

[0075] Friction modifier In some embodiments, the lubricating oil compositions herein include additional friction modifiers besides those included in the friction modifier systems described above. Suitable additional friction modifiers may include metal-containing and metal-free friction modifiers, and may include, but are not limited to, imidazolines, amides, amines, succinimides, alkoxylated amines, alkoxylated ether amines, amine oxides, amides, nitriles, betaine, quaternary amines, imines, amine salts, aminoguanidines, enolamides, phosphonates, metal-containing compounds, glycerides, sulfurized fatty compounds and olefins, sunflower oil, other naturally occurring vegetable or animal oils, dicarboxylic acid esters, polyols and esters or metaesters of one or more aliphatic or aromatic carboxylic acids, etc.

[0076] Suitable friction modifiers may contain a hydrocarbon group selected from straight-chain, branched, or aromatic hydrocarbon groups or mixtures thereof, and such hydrocarbon groups may be saturated or unsaturated. The hydrocarbon group may consist of carbon and hydrogen or heteroatoms (such as sulfur or oxygen). The hydrocarbon group may have between 12 and 25 carbon atoms. In some embodiments, the friction modifier may be a long-chain fatty acid ester. In another embodiment, the long-chain fatty acid ester may be a monoester, diester, or (tri)glycerol ester. The friction modifier may be a long-chain fatty amide, a long-chain fatty ester, a long-chain fatty epoxide derivative, or a long-chain imidazoline.

[0077] Other suitable friction modifiers may include organic, ashless (metal-free), nitrogen-free organic friction modifiers. Such friction modifiers may comprise esters formed by reacting carboxylic acids and anhydrides with alkanols, and typically contain polar terminal groups (e.g., carboxyl or hydroxyl groups) covalently bonded to a lipophilic hydrocarbon chain. Examples of organic ashless and nitrogen-free friction modifiers are generally known as glyceryl monooleate (GMO), which may contain monoesters, diesters, and trimers of oleic acid. Other suitable friction modifiers are described in U.S. Patent No. 6,723,685.

[0078] Amine-based friction modifiers may include amines or polyamines. These compounds may have straight-chain saturated or unsaturated hydrocarbon groups or mixtures thereof, and may contain 12 to 25 carbon atoms. Other examples of suitable friction modifiers include alkoxylated amines and alkoxylated ether amines. These compounds may have linear chains, saturated or unsaturated hydrocarbon groups, or mixtures thereof. They may contain about 12 to about 25 carbon atoms. Examples include ethoxylated amines and ethoxylated ether amines.

[0079] Amines and amides may be used as is or as additions or reaction products with boron compounds, such as boron oxide, boron halide, metaborates, boric acids or monoalkyl, dialkyl, or trialkyl esters of borate. Other suitable friction modifiers are described in U.S. Patent 6,300,291.

[0080] If the additional friction modifier contains nitrogen, such additional friction modifier can be present in the lubricating oil composition in any amount, as long as it does not impair performance requirements.

[0081] corrosion inhibitor Other rust inhibitors or corrosion inhibitors may also be included in the lubricating oil compositions described herein. Such materials include monocarboxylic acids and polycarboxylic acids. Examples of suitable monocarboxylic acids are octanoic acid, capric acid, and dodecanoic acid. Suitable polycarboxylic acids include dimer and trimer acids, such as those produced from tall oil fatty acids, oleic acid, linoleic acid, or their analogues.

[0082] Another useful type of rust inhibitor can be alkenyl succinic acid and alkenyl succinic anhydride corrosion inhibitors, such as, for example, tetrapropylene succinic acid, tetrapropylene succinic anhydride, tetradecenyl succinic acid, tetradecenyl succinic anhydride, hexadecenyl succinic acid, hexadecenyl succinic anhydride, etc. Also useful are half-esters of alkenyl succinic acid having 8 to 24 carbon atoms in the alkenyl group with alcohols (such as polyethylene glycol). Other suitable rust inhibitors or corrosion inhibitors include ether amines, acid phosphates, amines, polyethoxylated compounds such as ethoxylated amines, ethoxylated phenols and ethoxylated alcohols, imidazolines, aminosuccinic acid or derivatives thereof, etc. Mixtures of such rust inhibitors or corrosion inhibitors can be used. The total amount of corrosion inhibitor, when present in the lubricating composition described herein, can range from up to 2.0% by weight or from 0.01% by weight to 1.0% by weight, based on the total weight of the lubricating composition.

[0083] Viscosity modifier The lubricating oil composition may optionally contain one or more viscosity modifiers. Suitable viscosity modifiers may include polyolefins, olefin copolymers, ethylene / propylene copolymers, polyisobutylene, hydrogenated styrene-isoprene polymers, styrene / maleate copolymers, hydrogenated styrene / butadiene copolymers, hydrogenated isoprene polymers, α-olefin maleic anhydride copolymers, polymethyl methacrylates, polyacrylates, polyalkylstyrene, hydrogenated alkenylaryl conjugated diene copolymers, or mixtures thereof. Viscosity modifiers may include star polymers, and suitable examples are described in U.S. Publication 2012 / 0101017 A1.

[0084] In addition to or in place of viscosity modifiers, the lubricating oil compositions described herein may optionally contain one or more dispersant viscosity modifiers. Suitable dispersant viscosity modifiers may include functionalized polyolefins, such as ethylene-propylene copolymers functionalized with the reaction product of an acylation agent (such as maleic anhydride) and an amine; amine-functionalized polymethacrylates; or esterified maleic anhydride-styrene copolymers reacted with an amine.

[0085] Based on the total weight of the lubricating oil composition, the total amount of viscosity modifier and / or dispersant (if present) may be up to about 1.0% by weight, or up to about 0.5% by weight, or up to about 0.3% by weight.

[0086] Demulsifier Demulsifiers may also be included in the compositions herein and may include trialkyl phosphates, and various polymers and copolymers of ethylene glycol, ethylene oxide, propylene oxide, or mixtures thereof, including polyethylene oxide, polypropylene oxide, and (ethylene oxide-propylene oxide) polymers. When present, the amount of demulsifier in the lubricating oil composition may be up to about 0.05% by weight, up to about 0.02% by weight, or less than about 0.015% by weight based on the total weight of the lubricating oil composition.

[0087] Defoamer Defoamers used to reduce or prevent the formation of stable foams include siloxanes, polyacrylates, or organic polymers. Foam inhibitors that can be used in the compositions of the disclosed invention include polysiloxanes, copolymers of ethyl acrylate and 2-ethylhexyl acrylate, and optionally vinyl acetate. When present, the amount of defoamer in the lubricating oil composition may be at most about 0.1% by weight, or at most about 0.05% by weight, or less than about 0.04% by weight, based on the total weight of the lubricating oil composition.

[0088] Pour point depressant The lubricating oil composition may optionally contain one or more pour point depressants. Suitable pour point depressants may include maleic anhydride-styrene esters, polymethyl methacrylates, polyacrylates, polyacrylic acid esters, or polyacrylamide, or mixtures thereof. Based on the total weight of the lubricant, the pour point depressant (if present) may be present in an amount from about 0.001% by weight to about 0.04% by weight.

[0089] Generally, the lubricating oil compositions described herein may include additive components within the range listed in Table 2.

[0090] Table 2

[0091]

[0092] The percentages for each component above represent the weight percentage of each component based on the total weight of the lubricating oil composition containing said component. Additives used to formulate the compositions described herein can be blended into the base oil individually or in various sub-combinations. However, it may be suitable to simultaneously blend all components using an additive concentrate (i.e., an additive plus a diluent, such as a hydrocarbon solvent). The use of an additive concentrate utilizes the compatibility offered by the combination of components in additive concentrate form. Furthermore, the use of a concentrate reduces blending time and the possibility of blending errors.

[0093] Unless the context in which this is discussed implies otherwise, the following definitions of terms are provided to clarify the meaning of certain terms as used herein.

[0094] The terms “lubricating oil,” “lubricant composition,” “lubricating compound,” “lubricant,” and “lubricating oil composition” refer to finished lubricating products comprising a major amount of a base oil plus a minor amount of an additive composition. As used herein, the major amount includes at least 50% by weight or more, and the minor amount includes less than 50% by weight.

[0095] As used herein, the terms “additive package,” “additive concentrate,” and “additive composition” refer to a portion of a lubricating oil composition that does not include a major amount of base oil.

[0096] As used herein, the term "hydrocarbon substituent" or "hydrocarbon group" is used in its common sense, as is well known to those skilled in the art. Specifically, it refers to a group having a carbon atom directly connected to the rest of the molecule and having predominantly hydrocarbon characteristics. Each hydrocarbon group is independently selected from hydrocarbon substituents and hydrocarbon substituents containing one or more of a halogen group, hydroxyl group, alkoxy group, mercapto group, nitro group, nitroso group, amino group, pyridyl group, furanyl group, imidazolyl group, oxygen, and nitrogen, and wherein there are no more than two non-hydrocarbon substituents present for every ten carbon atoms in the hydrocarbon group.

[0097] As used herein, unless otherwise expressly stated, the terms “weight percentage” or “weight %” mean the percentage of the said component by weight of the whole composition.

[0098] As used herein, the terms “soluble,” “oil-soluble,” or “dispersible” may, but do not necessarily, mean that a compound or additive is soluble, miscible, or capable of being suspended in oil in all proportions. However, the foregoing terms do mean that they are, for example, soluble, suspended, dispersible, or stably dispersed in oil to a degree sufficient to exert their intended effect in an environment where oil is used. Furthermore, if desired, additional admixtures may be permitted at higher levels of specific additives.

[0099] As used herein, the term "alkyl" refers to a straight-chain, branched, cyclic, and / or substituted saturated chain moiety of about 1 to about 200 carbon atoms.

[0100] As used herein, the term "alkenyl" refers to a straight-chain, branched, cyclic, and / or substituted unsaturated chain portion of about 3 to about 30 carbon atoms.

[0101] As used herein, the term "aryl" refers to monocyclic and polycyclic aromatic compounds, which may include alkyl, alkenyl, alkylaryl, amino, hydroxyl, alkoxy, halogen substituents and / or heteroatoms including but not limited to nitrogen and oxygen.

[0102] As used herein, “number-average molecular weight” or “Mn” was determined by gel permeation chromatography (GPC) using commercially available polystyrene standards (where Mn was approximately 180 to approximately 18,000 as a calibration reference).

[0103] It should be understood that throughout this disclosure, the terms “comprising,” “including,” “containing,” etc., are considered open-ended and include any element, step, or ingredient not expressly listed. The phrase “consisting substantially of…” means including any expressly listed element, step, or ingredient, as well as any additional element, step, or ingredient that does not substantially affect the basic and novel aspects of the invention. This disclosure also considers that any composition described using the terms “comprising,” “including,” or “containing” is also to be interpreted as including the disclosure of the same composition “consisting substantially of its specifically listed components” or “consisting of its specifically listed components.”

[0104] Example

[0105] The present disclosure and its many advantages can be better understood through the following examples. These examples are illustrative and do not limit its scope or spirit. Those skilled in the art will readily understand that variations of the components, methods, steps, and apparatus described in these examples can be used. Unless otherwise stated or apparent from the context of the examples below and the discussion throughout the disclosure and claims, all percentages, ratios, and parts indicated in this disclosure are by weight. Any standardized test methods indicated in the examples, disclosure, or claims, unless obvious from the context of their use, refer to a version of the test method publicly available at the time of filing this disclosure.

[0106] The embodiments described herein evaluate mean random pre-ignition (SPI) events using a 7.7-liter mid-sized 6-cylinder inline H2 engine (where H2 fuel has an autoignition temperature of approximately 850 K to 858 K) at FEV Europe GmbH, with a peak cycle pressure of 160 bar average and 180 bar maximum. The crank angle was adjusted to a position that neither promotes nor reduces SPI. SPI was evaluated by measuring the SPI count in each cylinder at 12 bar mean effective pressure (BMEP) at 1000 rpm, for a total of 150 measurements. Each measurement comprised 500 cycles per cylinder. The average SPI per 500 cycles of the engine was determined by calculating the average events across all 6 cylinders.

[0107] Table 3 below describes the first group of lubricants: comparative lubricants 1-3 and lubricants 1-3 of the present invention. The lubricants contain the same base additive package, which includes the same amounts and types of dispersants, antioxidants, defoamers, friction modifiers, and viscosity modifiers. Only the detergent system and ZDDP anti-wear additive differ between the lubricants, as shown in Table 3 below. The processing oil in the base package varies slightly to accommodate the changes in processing rates in the detergent system. The lubricants are blended in the same base oil blends of API Group II base oils and have a kV of approximately 14 cSt at 100°C.

[0108] Table 4 below describes another lubricant, Example 4 of the present invention. This lubricant contains a different base additive package and includes a variation of the detergent system of the present invention. The formulation was tested at its treatment rate in API Group II base oils to obtain a finished fluid with approximately 15 cSt at 100°C and kV.

[0109] The differences arising from variations in the detergent system (i.e., the amount of calcium and magnesium delivered to the lubricant), the TBN (ASTM D2896) of the lubricant, and the measured sulfate ash content (ASTM D874) of the lubricant are detailed in Table 5. The detergents used in the lubricants of these examples are as follows:

[0110] • Detergent Additive 1 (Det-1) A highly alkaline calcium sulfonate detergent with approximately 300 TBN (measured by ASTM D2896) and approximately 11.9% by weight of calcium.

[0111] • Detergent Additive 2 (Det-2) A low-alkaline to neutral calcium sulfonate detergent with approximately 25 to 50 TBN (measured by ASTM D2896) and approximately 2.7% by weight of calcium.

[0112] • Detergent Additive 3 (Det-3) A highly alkaline phenolic calcium detergent with approximately 250 TBN (measured by ASTM D2896) and approximately 9.25% by weight of calcium.

[0113] • Detergent Additive 4 (Det-4) A highly alkaline magnesium sulfonate detergent with approximately 400 TBN (measured by ASTM D2896) and approximately 9.6% by weight of magnesium.

[0114] Table 3: Lubricant Formulation

[0115]

[0116] Table 4: Lubricant Formulation

[0117]

[0118] Additional additives include antioxidants, defoamers, processing oils, and pour point depressants.

[0119] Table 5: Lubricant Properties

[0120]

[0121] Exemplary mmol calculation for Example 4 of the present invention: 0.741g Det 4 × 9.6 wt% Mg = approximately 0.0711g Mg / 0.0234g / mmol = approximately 3.04 mmol of Mg delivered from the highly alkaline sulfonate detergent to the lubricant. Other metal amounts were determined in a similar manner.

[0122] An exemplary ratio calculation for Example 4 of the present invention: (3.04 mmol of metal from the highly alkaline sulfonate detergent / (3.04 mmol + 3.10 mmol + 0.03 mmol)) / 10 of TBN = approximately 0.05.

[0123] Table 6: SPI Evaluation (Average SPI Count, Load Scan, 1000rpm, 12bar BMEP)

[0124]

[0125] ASTM D8291, which evaluates each lubricant composition in conventional gasoline-fueled engines.

[0126] As shown in Tables 5 and 6 (and Figure 1 As shown in the comparative lubricant samples 1-3 in the table, if the metal delivered from the high-alkalinity sulfonate detergent is not properly balanced relative to the total detergent metal and / or the percentage of metal from the high-alkalinity sulfonate detergent is not properly balanced relative to the TBN (e.g., as shown in Table 5 and...), Figure 1 The metal mmol amounts shown (and / or a contrast ratio higher than 0.07) indicate that when the lubricant is used in a hydrogen fuel cell internal combustion engine, the average SPI is unacceptably high (e.g., higher than 6). However, as shown in Tables 5 and 6 (and Figure 1 As shown in samples 1-4 of the present invention, when the metal delivered from the high-alkalinity sulfonate detergent is properly balanced relative to the total detergent metal and / or the percentage of metal from the high-alkalinity sulfonate detergent is properly balanced relative to the TBN (e.g., as shown in Table 5 and...), Figure 1 If the selected metal mmol amount and / or ratio of 0.07 or less are shown, then the average SPI events are minimized (e.g., 6 or less) when the lubricant is used in a hydrogen fuel internal combustion engine. Figure 1 Improvements to the SPI implementation are also shown, including properly balancing the percentage of high-alkaline sulfonate metals relative to TBN for suitability for alternative fuel engines, particularly hydrogen fuel engines. Data in Table 6 also show that lubricants that pass LSPI Sequence IX (ASTM D8291) in conventional gasoline engines do not necessarily achieve SPI in hydrogen fuel internal combustion engines.

[0127] It should be understood that although the lubricating compositions and formulations of this disclosure have been described in conjunction with their detailed description and summary herein, the foregoing description is intended to be illustrative and not limiting of the scope of this disclosure, which is defined by the scope of the appended claims. Other aspects, advantages, and modifications are also within the scope of the claims. This specification and the examples are intended to be illustrative only, wherein the true scope of this disclosure is indicated by the appended claims.

[0128] Other embodiments of this disclosure will be apparent to those skilled in the art upon consideration of the practice of this specification and the embodiments disclosed herein. As used throughout the specification and claims, “a / an (a)” and / or “an / an (a)” may refer to one or more. Unless otherwise indicated, all figures expressing quantities of components and properties, such as molecular weight, percentage, ratio, reaction conditions, etc., used in this specification should be understood to be modified in all cases by the term “about,” regardless of whether the term “about” is present. Therefore, unless indicated to the contrary, the numerical parameters set forth in this specification are approximations that may vary depending on the desired properties sought to be obtained through this disclosure. To a minimum, and without attempting to limit the application of the equivalence principle to the scope of the claims, each numerical parameter should be interpreted at least according to the number of significant figures reported and by applying general rounding techniques. Although the numerical ranges and parameters set forth in the broad scope of this disclosure are approximations, the values ​​set forth in particular embodiments are reported as precisely as possible. However, any numerical value inherently contains some error necessarily caused by the standard deviation found in its corresponding test measurement.

[0129] It should be understood that each component, compound, substituent or parameter disclosed herein should be interpreted as disclosed for use alone or in combination with one or more of each other component, compound, substituent or parameter disclosed herein.

[0130] It should also be understood that each range disclosed herein should be interpreted as a disclosure of each specific value within the disclosed range having the same significant digits. Thus, the range 1-4 will be interpreted as an explicit disclosure of the values ​​1, 2, 3, and 4, as well as any range of these values, such as 1-4, 1-3, 1-2, 2-4, 2-3, etc.

[0131] It should also be understood that each lower limit of each range disclosed herein should be interpreted as a combination of each upper limit of each range and each specific value within each range disclosed herein for the same component, compound, substituent, or parameter. Therefore, this disclosure should be interpreted as a disclosure of all ranges derived by combining each lower limit of each range with each upper limit of each range or with each specific value within each range, or by combining each upper limit of each range with each specific value within each range.

[0132] Furthermore, the specific amounts / values ​​of components, compounds, substituents, or parameters disclosed in this specification or examples should be interpreted as disclosures of a lower or upper limit of a range, and therefore can be combined with any other lower or upper limit or specific amount / value of the range of the same components, compounds, substituents, or parameters disclosed elsewhere in this disclosure to form such a range of components, compounds, substituents, or parameters.

Claims

1. A lubricating oil composition configured for lubricating an internal combustion engine fueled by fuel with an auto-ignition temperature above about 700 K, the lubricating oil composition comprising: One or more base oils with lubricating viscosity; Detergent system, the detergent system comprising (i) at least one highly alkaline metal sulfonate detergent that provides about 2 mmol to about 12 mmol of metal to the composition; (ii) Optionally, at least one neutral to low-alkaline metal sulfonate detergent that provides at least about 0.02 mmol of metal to the composition; The lubricating oil composition described herein has a total base number (TBN) of at least about 9.5 as measured according to ASTM D2896; and The percentage of metal provided by the highly alkaline metal sulfonate detergent is approximately 0.07 or less relative to the TBN (ASTM D2896) of the lubricating oil composition.

2. The lubricating oil composition according to claim 1, wherein the detergent system further comprises at least one highly alkaline metal-containing phenolic detergent that provides the composition with up to about 4 mmol of metal.

3. The lubricating oil composition of claim 2, wherein the detergent system provides only calcium, only magnesium, or a blend of calcium and magnesium; and / or wherein the TBN of the lubricating oil composition is measured to be about 10 to about 15 according to ASTM D2896.

4. The lubricating oil composition according to claim 1, wherein the lubricating oil composition has a sulfate ash (SASH) content greater than 0.9% by weight as measured according to ASTM D874; or wherein the lubricating oil composition has a sulfate ash (SASH) content greater than 1.2% by weight as measured according to ASTM D874.

5. The lubricating oil composition of claim 1, wherein the detergent system provides about 1,000 ppm to about 5,000 ppm of a metal selected from calcium, magnesium, or combinations thereof; and / or wherein the detergent system provides about 1,500 ppm to about 3,000 ppm of magnesium.

6. The lubricating oil composition of claim 1, wherein the composition further comprises one or more oil-soluble molybdenum compounds providing about 200 ppm or less of molybdenum; and / or wherein the detergent system comprises at least a highly alkaline magnesium sulfonate detergent having at least about 200 TBN (ASTM D2896).

7. The lubricating oil composition according to claim 1, wherein the one or more base oils having lubricating viscosity include API Group I base oils, API Group II base oils, or combinations thereof.

8. The lubricating oil composition of claim 1, wherein the composition is configured for lubricating an internal combustion engine fueled by fuel with an auto-ignition temperature above about 800 K; and / or wherein the composition is configured for lubricating an internal combustion engine fueled by fuel with an auto-ignition temperature above about 850 K; and / or wherein the lubricating oil composition has an average measured SPI of about 6 random pre-ignition (SPI) counts or less at 1000 rpm and 12 bar brake mean effective pressure (BMEP); and / or wherein the fuel with an auto-ignition temperature above about 700 K is hydrogen fuel.

9. A method for lubricating an internal combustion engine to mitigate abnormal combustion events when using fuel with an auto-ignition temperature above about 700K, the method comprising: The crankcase of an internal combustion engine is lubricated with a lubricating oil composition and fuel with an auto-ignition temperature above about 700 K is burned in the internal combustion engine. and The lubricating oil composition comprises (i) one or more base oils having a lubricating viscosity and (ii) a detergent system comprising (iia) at least one highly alkaline metal sulfonate detergent that provides about 2 mmol to about 12 mmol of metal to the composition; (iib) optionally, at least one neutral to low alkaline metal sulfonate detergent that provides at least about 0.02 mmol of metal to the composition; wherein the lubricating oil composition has a total base number (TBN) of at least about 9.5 as measured according to ASTM D2896; and wherein the percentage of metal provided by the highly alkaline metal sulfonate detergent is about 0.07 or less relative to the TBN (ASTM D2896) of the lubricating oil composition.

10. The method of claim 9, further comprising at least one highly alkaline metal-containing phenolic detergent that provides up to about 4 mmol of metal to the composition; and / or wherein the detergent system provides only calcium, only magnesium, or a blend of calcium and magnesium; and / or wherein the TBN of the lubricating oil composition is about 10 to about 15 as measured according to ASTM D2896; and / or wherein the lubricating oil composition has a sulfate ash (SASH) content greater than 0.9% by weight as measured according to ASTM D874; and / or wherein the lubricating oil composition has a sulfate ash (SASH) content greater than 1.2% by weight as measured according to ASTM D874.

11. The method of claim 9, wherein the detergent system provides about 1,000 ppm to about 5,000 ppm of a metal selected from calcium, magnesium, or combinations thereof; and / or wherein the detergent system provides about 1,500 ppm to about 3,000 ppm of magnesium; and / or wherein the composition further comprises one or more oil-soluble molybdenum compounds providing about 200 ppm or less of molybdenum; and / or wherein the detergent system comprises at least a highly alkaline magnesium sulfonate detergent having at least about 200 TBN (ASTM D2896).

12. The method of claim 9, wherein the one or more base oils having lubricating viscosity comprise API Group I base oils, API Group II base oils, or combinations thereof; and / or wherein the composition is configured for lubricating an internal combustion engine fueled by fuel with an auto-ignition temperature above about 800 K; and / or wherein the composition is configured for lubricating an internal combustion engine fueled by fuel with an auto-ignition temperature above about 850 K; and / or wherein the fuel with an auto-ignition temperature above about 700 K is hydrogen fuel, compressed natural gas, or liquefied natural gas; and / or wherein the lubricating oil composition has an average measured SPI of about 6 random pre-ignition (SPI) counts or less at 1000 rpm and 12 bar brake mean effective pressure (BMEP).

13. An internal combustion engine configured for burning hydrogen fuel, the internal combustion engine comprising: Engine crankcase lubricated with a lubricating oil composition; The lubricating oil composition comprises (i) one or more base oils having a lubricating viscosity and (ii) a detergent system comprising (iia) at least one highly alkaline metal sulfonate detergent that provides about 2 mmol to about 12 mmol of metal to the composition; (iib) optionally, at least one neutral to low alkaline metal sulfonate detergent that provides at least about 0.02 mmol of metal to the composition; wherein the lubricating oil composition has a total base number (TBN) of at least about 9.5 as measured according to ASTM D2896; and wherein the percentage of metal provided by the highly alkaline metal sulfonate detergent is about 0.07 or less relative to the TBN (ASTM D2896) of the lubricating oil composition. and Hydrogen fuel.

14. The internal combustion engine of claim 13, further comprising at least one highly alkaline metal-containing phenolic detergent that provides up to about 4 mmol of metal to the composition; and / or wherein the detergent system provides only calcium, only magnesium, or a blend of calcium and magnesium; and / or wherein the TBN of the lubricating oil composition is about 10 to about 15 as measured according to ASTM D2896; and / or wherein the lubricating oil composition has a sulfate ash (SASH) content greater than 0.9% by weight as measured according to ASTM D874; and / or wherein the lubricating oil composition has a sulfate ash (SASH) content greater than 1.2% by weight as measured according to ASTM D874.

15. The internal combustion engine of claim 13, wherein the detergent system provides about 1,000 ppm to about 5,000 ppm of a metal selected from calcium, magnesium, or combinations thereof; and / or wherein the detergent system provides about 1,500 ppm to about 300 ppm of magnesium; and / or wherein the composition further comprises one or more oil-soluble molybdenum compounds, the oil-soluble molybdenum compounds providing about 200 ppm or less of molybdenum.

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