JP2014101513A - Marine engine lubrication - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent or inhibit asphaltene precipitation in a lubricant composition caused by a contaminant heavy fuel oil.SOLUTION: A trunk piston marine engine lubricant comprises a major amount of (A) an oil of lubricating viscosity that comprises an oil-soluble ester basestock, or that comprises greater than 0.1 mass% and less than 90 mass% of an oil-soluble basestock and, as 50 mass% or more of the remainder of the oil of lubricating viscosity, a high saturates basestock; (B) a minor amount of a metal alkyl salicylate detergent; and (C) greater than 0.1 mass% and less than 10 mass% of an oil-soluble polyalkenyl-substituted carboxylic acid anhydride, where at least one polyalkenyl group is derived from a polyalkene having a number average molecular weight of 200 to 3000.

Description

  The present invention relates to trunk piston marine engine lubricating compositions for medium speed four-stroke compression ignition (diesel) marine engines and the lubrication of such engines.

  Marine trunk piston engines generally use heavy fuel oil (HFO) for offshore operation. Heavy oil is the heaviest fraction of petroleum distillates and is a petroleum distillate that is insoluble in excess aliphatic hydrocarbons (eg, heptane) but soluble in aromatic solvents (eg, toluene). Contains a complex mixture of molecules containing up to 15% asphaltenes, defined as fractions. Asphaltenes can be incorporated as contaminants in engine lubricants via cylinders or fuel pumps and injectors, thereby causing precipitation of asphaltenes, resulting in “black paint” or “black sludge” in the engine. The presence of such carbonaceous deposits on the piston surface can act as an insulating layer, resulting in cracks propagating through the piston. When cracks propagate through the piston, hot combustion gases can enter the crankcase and lead to an explosion of the crankcase.

  Therefore, it is highly desirable that trunk piston engine oils (TPEOs) prevent or inhibit the precipitation of asphaltenes. TPEO using Group 1 basestocks may have the ability to solubilize asphaltenes. However, TPEO with a high saturate base stock (eg, Group II or III) requires an enhancer to achieve a similar level of performance in this regard.

  WO 2010/115594 (hereinafter “594”) and WO 2010/115595 (hereinafter “595”) each have a small amount in a trunk piston ship engine lubricating oil composition containing 50% by weight or more of Group II base stock. Disclosed is the use of calcium salicylate detergent and polyalkenyl substituted carboxylic acids and acid anhydrides. Data in “594” and “595” indicates that the combination improves the dispersibility of asphaltenes.

  US2011 / 0319304A1 (hereinafter “304”) discloses the use of an ester base stock in a high saturate base stock TPEO to improve the dispersibility of asphaltenes.

  The challenge in the art is to further improve the asphaltene dispersibility of TPEO using high saturates basestock.

  The present invention solves the above problems by using anhydrides and esters in TPEO, and a synergistic effect is observed as shown by the data in this specification.

A first aspect of the present invention is a trunk piston marine engine lubricating oil composition for use in the operation of an engine fueled with heavy oil to improve the handling of asphaltenes, the composition comprising: Contains or mixes the following:
(A) an oil-soluble ester base stock (A1); or an oil soluble ester base stock (A1) of more than 0.1% by weight and less than 90% by weight, preferably more than 1% by weight and less than 80% by weight. A large amount of oil of lubricating viscosity comprising 90% or more of saturates and base stock (A2) containing 0.03% or less of sulfur or mixtures thereof, as the remaining 50% or more by weight of oil of lubricating viscosity ;
(B) a small amount of an oil-soluble metal detergent; and (C) a small amount of oil-soluble polyalkenyl-substituted carboxylic acid anhydride of more than 0.1% by weight and less than 10% by weight, preferably more than 1% by weight and less than 8% by weight. (The polyalkenyl group or at least one polyalkenyl group is derived from a polyalkene having a number average molecular weight of 200 to 3000).

A second aspect of the present invention is a method for operating a trunk piston medium speed compression ignition marine engine, which includes the following.
(I) supplying heavy oil to the engine; and (ii) lubricating the crankcase of the engine with the composition according to the first aspect of the present invention.

A third aspect of the present invention is a method for dispersing asphaltenes in a trunk piston ship lubricating oil composition during lubrication of the combustion chamber surface of a medium speed compression ignited ship engine and during engine operation, the method comprising: .
(I) providing a composition according to the first aspect of the present invention;
(Ii) supplying the composition into the combustion chamber;
(Iii) supplying heavy oil into the combustion chamber; and (iv) burning heavy oil in the combustion chamber.

  A fourth aspect of the present invention relates to a component (C) of the cleaning agent (B) defined in the first aspect of the present invention in a trunk piston marine lubricating oil composition for a medium speed compression ignition marine engine. Use in an amount as defined in the first aspect by combination, the composition comprising a large amount of oil (A) of lubricating viscosity as defined in the first aspect, at the time of heavy oil supply engine operation, Depending on the composition, the base stock provides asphaltene handling and lubricity that is comparable or improved compared to the corresponding oils that are Group 1 base stocks.

  In this specification, when the following words and expressions are used, the following meanings are expressed.

  Active ingredients or “(ai)” refers to an additive that is not a diluent or solvent.

  “Contains” or all synonyms specify the presence of the stated feature, step, integer, or component, but the presence or absence of one or more other features, steps, integers, components, or collections thereof The expression “consisting of” or “consisting essentially of” or synonyms may be included within the scope of “contains” or synonyms, where “from “Become” allows for inclusion of materials that do not substantially affect the characteristics of the applied composition.

  “Large amount” means 50% by weight or more of the composition, preferably 60% by weight or more, more preferably 70% or more, and even more preferably 80% by weight.

  “Small amount” means less than 50% by weight of the composition, preferably less than 40% by weight, more preferably less than 30% by weight, even more preferably less than 20% by weight. .

  “TBN” means total base number as measured by ASTM D2896.

Further, as used herein, when used:
“Calcium content” is measured according to ASTM 4951;
"Phosphorus content" is measured according to ASTM D5185;
“Sulfate ash content” is measured according to ASTM D874;
“Sulfur content” is measured according to ASTM D2622,
“KV100” means the kinematic viscosity at 100 ° C. as measured by ASTM D445.

  In addition, the various components used (not only essential but also optimal and customary) may react under conditions of preparation, storage, or use, and the present invention provides: It will also be understood that any such reaction may result or provide a product obtained.

  Further, it is understood that any amount upper and lower limits, ranges, and ratio limits described herein may be independently combined.

  The features of the present invention are described in detail below.

Oil of lubricating viscosity (A)
Ester base stock (A1)
These are organic ester base stocks, including but not limited to monoesters, diesters, polyol esters, and polymer esters. These are generally considered Group V base stocks and are typically derived from animal or plant sources. Naturally derived organic esters can be found in animal or vegetable oils. Organic esters may be synthesized by reacting organic acids with alcohols.

  Monoesters can be prepared by reacting a monohydric alcohol with a monobasic fatty acid to produce a molecule having a single ester bond and a linear or branched alkyl group.

  Diesters are monohydric alcohols (eg, butyl alcohol, hexyl alcohol, dodecyl alcohol, 2-ethylhexyl alcohol, ethylene glycol, diethylene glycol monoether, propylene glycol) and dibasic acids (eg, phthalic acid, succinic acid, alkyl succinic acid). (Alkyl succinic acid), alkenyl succinic acid, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, linoleic acid dimer, malonic acid, alkylmalonic acid, Reaction with alkenyl malonic acid) may be linear, branched or aromatic. By generating a molecule having two ester groups may be prepared. Specific examples of such esters include dibutyl adipate, di (2-ethylhexyl) sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, didecyl phthalate , Dieicosyl sebacate, 2-ethylhexyl diester of linoleic acid dimer, and complex esters formed by reacting 1 mol of sebacic acid with 2 mol of tetraethylene glycol and 2 mol of 2-ethylhexanoic acid It is done.

  A polyol ester comprises one or more polyols (eg neopentyl glycol, trimethylolpropane, pentaerythritol, dipentaerythritol and tripentaerythritol) by one or more organic acids (eg C5-C12 monocarboxylic acids). It can be prepared by esterification. See for example US-A-6,462,001. Examples of polyol esters include trimethylolpropane (TMP) esters.

  Tricarboxylic acid esters are also suitable. The tricarboxylic acid ester is preferably benzene tricarboxylic acid. A preferred benzenetricarboxylic acid ester is 1,2,4-benzenetricarboxylic acid having an alkyl chain that is 5 to 10 (preferably 7 to 9) in length. A preferred 1,2,4-benzenetricarboxylic acid is trioctyl trimellitate.

Examples of the ester base stock for use in the present invention, 100 ° C. and having a kinematic viscosity of 2 to 10 mm ² s ^-1 at, at 100 ° C. until 10 mm ² s ^-1 greater than 100 mm ² s ^-1 Those having a kinematic viscosity are listed. A specific example of a suitable polyol ester is Priolube (R) 3970, which is an ester of neopentyl polyol (optionally TMP) and has at least one aliphatic saturated monocarboxylic acid, 6-12 The kinematic viscosity at 100 ° C. is 4.4 mm ² s ⁻¹ .

  The ester base stock may be present in an amount of 2 to 85 (preferably 5 to 50, more preferably 8 to 40)% by weight.

Base stock (A2)
These may have viscosities from light distillate mineral oil to heavy lubricating oil. Generally, the viscosity of the oil is 2 or more and 40 mm ² s ⁻¹ or less when measured at 100 ° C.

  Natural oils include animal and vegetable oils (eg, castor oil, lard oil), liquid petroleum, and hydrorefined, solvent-treated, or acid-treated paraffinic, naphthenic, or paraffinic and naphthenic oils. Mention may be made of mixed types of mineral oil. Oils of lubricating viscosity derived from coal or shale are also available as useful base oils.

  Synthetic lubricating oils include hydrocarbon oils and halo-substituted hydrocarbon oils such as polymerized and copolymerized olefins (eg, polybutylene, polypropylene, propylene-isobutylene copolymer, chlorinated polybutylene, poly (1-hexene), poly (1-hexene). Octene), poly (1-decene)); alkylbenzenes (eg, dodecylbenzene, tetradecylbenzene, dinonylbenzene, di (2-ethylhexyl) benzene); polyphenyls (eg, biphenyl, terphenyl, alkylated polyphenols); And alkylated diphenyl ethers, alkylated diphenyl sulfides, derivatives, analogs and homologues thereof.

  Unrefined, refined, and rerefined oils can be used in the lubricants of the present invention. Unrefined oils are obtained directly from natural or synthetic raw materials without further purification. For example, shale oil obtained directly from the carbonization process; and petroleum oil obtained directly from the distillate are unrefined oils. Refined oils are similar to unrefined oils except that one or more refinements are further applied to the oil to improve one or more properties. Many such purification techniques are known to those skilled in the art, such as distillation, solvent extraction, acid or base extraction, filtration and percolation. The re-refined oil is obtained by a method similar to that used to obtain the refined oil, but the oil already used is used as a raw material. Such rerefined oils are also known as reclaimed or reprocessed oils and are often further processed using techniques to remove ineffective additives and oil breakdown products.

  The American Petroleum Institute (API) publication "Engine Oil Licensing and Authorization System" Industrial Services Division, Volume 14, December 1996, Addendum 1, December 1998 classifies base stocks as follows:

  Group I basestocks contain less than 90% saturates and / or more than 0.03% sulfur and have a viscosity index of 80 to less than 120 when using the test method specified by Table E-1.

  Group II base stocks contain 90% or more of saturates and 0.03% or less of sulfur and have a viscosity index of 80 to less than 120 when using the test method specified by Table E-1.

  Group III base stocks contain greater than 90% saturates and less than 0.03% sulfur and have a viscosity index greater than 120 when using the test method specified by Table E-1.

  Group IV base stock is polyalphaolefin (PAO).

  Group V base stock includes all other base stocks not included in Group I, II, III, or IV.

The base stock analysis method is shown in the table below.
(Table E-1)

  For example, base stock (A2) includes Group II, Group III, and Group IV base stocks as well as hydrocarbon derived base stocks synthesized using the Fischer-Tropsch process. In the Fischer-Tropsch process, synthesis gas (or syngas) containing carbon monoxide and hydrogen is first produced and then converted to hydrocarbons using a Fischer-Tropsch catalyst. These hydrocarbons usually require further processing because they are useful as base oils. For example, they can be hydroisomerized; hydrocracked and hydroisomerized; degreased; or hydroisomerized and degreased using techniques well known in the art. Syngas, for example, when the basestock is a gas-to-liquid “GTL” base oil, by steam reforming from a gas such as natural gas or other gaseous hydrocarbons If the base stock is a biomass-to-liquid “BTL” or “BMTL” base oil, it can be produced by biogasification and the base stock is called In the case of a coal-to-liquid “CTL” base oil, it can be produced by coal gasification.

  As described above, when used in the present invention, the base stock (A2) includes 50% by mass or more of the defined base stock or a mixture thereof. Preferably, it comprises 60% by weight or more, for example 70, 80 or 90% by weight or more of the defined base stock or mixtures thereof. (A2) may comprise substantially all defined base stocks or mixtures thereof.

Overbased metal detergent (B)
Metal detergents are additives based on so-called metal “soaps”, which are metal salts of acidic organic compounds, and are sometimes referred to as surfactants. They generally have a polar head with a long hydrophobic tail. An overbased metal detergent that includes a neutralized metal detergent as the outer layer of a metal base (eg, carbonate) micelle is an excess of a metal base (eg, oxide or hydroxide) that is an acid gas (eg, carbon dioxide). Can be provided by reacting with a large amount of metal base. Examples of cleaning agents include metal salicylates, carbonates, salicylates and combinations thereof.

  In the present invention, the overbased metal detergent (B) is preferably an overbased metal hydrocarbyl substituted hydroxybenzoate, more preferably a hydrocarbyl substituted salicylate detergent. The metal may be an alkali metal (eg Li, Na, K) or an alkaline earth metal (eg Mg, Ca).

ここで、Ｒは、直鎖アルキル基である。ベンゼン環には、１個より多くの基Ｒが結合していてもよい。ＣＯＯ^-基は、ヒドロキシル基に対してオルト、メタ、又はパラ位に存在することができ；オルト位が好ましい。基Ｒは、ヒドロキシル基に対して、オルト、メタ、又はパラ位に存在することができる。 “Hydrocarbyl” means a group or radical containing carbon and hydrogen atoms that is bonded to the remainder of the molecule through a carbon atom. This may contain heteroatoms, ie atoms other than carbon and hydrogen, provided that they do not change the essential hydrocarbon properties and characteristics of the group. Examples of hydrocarbyl include alkyl and alkenyl. A preferred overbased metal hydrocarbyl substituted hydroxybenzoate is a calcium alkyl substituted salicylate and has the structure shown below:

Here, R is a linear alkyl group. More than one group R may be bonded to the benzene ring. The COO ^- group can be in the ortho, meta or para position relative to the hydroxyl group; the ortho position is preferred. The group R can be in the ortho, meta, or para position relative to the hydroxyl group.

  Salicylic acid is typically prepared by carboxylation of phenoxide using the Kolbe-Schmidt method, in which case it is generally obtained as a mixture (usually in a diluent) with uncarboxylated phenol. Salicylic acid may be non-sulfurized, sulfurized, chemically modified, and / or may contain additional substituents. Alkylsalicylic acid sulfidation processes are well known to those skilled in the art and are described, for example, in US 2007/0027057.

  The alkyl group advantageously contains 5 to 100, preferably 9 to 30, in particular 14 to 24 carbon atoms.

  The term “overbased” is generally used to describe metal detergents in which the ratio of the number of equivalents of metal moieties to the number of equivalents of acid moieties is greater than one. The term “low basicity” is used to describe a metal detergent wherein the equivalent ratio of metal moiety to acid moiety is greater than 1 to about 2.

  “Surfactant overbased calcium salt” means an overbased detergent in which the metal cation of the oil-insoluble metal salt is substantially calcium cation. Other small amounts of cations may be present in the oil-insoluble metal salt, but of the cations in the oil-insoluble metal salt, typically at least 80 mol%, more typically at least 90 mol%, such as At least 95 mol% is calcium ions. For example, cations other than calcium may be derived from the use of surfactant salts where the cation is a metal other than calcium during the manufacture of the overbased detergent. Preferably, the metal salt of the surfactant is also calcium.

  Carbonated overbased metal detergents typically include amorphous nanoparticles. In addition, there are disclosures of nanoparticulate materials comprising carbonate in the form of crystalline calcite and vaterite.

  The basicity of the cleaning agent can be expressed by a total base number (total base number (TBN)), and is sometimes referred to as the base number (base number (BN)). Total base number is the amount of acid required to neutralize the total basicity of the overbased material. TBN can be measured by ASTM standard D2896 or an equivalent technique. The cleaning agent may have a low TBN (ie, less than 50 TBN), may have a medium TBN (ie, 50-150 TBN), or may have a high TBN (ie, more than 150). For example, 150-500 TBN). The basicity can also be expressed by a basicity index (BI), which is the molar ratio of all bases to all soaps in an overbased detergent.

Polyalkenyl substituted carboxylic acid anhydride (C)
The acid anhydride may constitute at least 1 to 7% by mass, preferably 2 to 6% by mass, of the lubricating oil composition. Preferably it constitutes 3-5% by weight, even more preferably 4-5% by weight.

  The acid anhydride may be a mono- or polycarboxylic acid, and is preferably a dicarboxylic acid. The polyalkenyl group preferably contains 8 to 400, for example 8 to 100 carbon atoms.

ここで、Ｒ¹は、Ｃ８〜Ｃ１００の分岐又は直鎖ポリアルケニル基を表す。 An example of an acid anhydride may be represented by the following general formula:

Here, R ¹ represents a C8 to C100 branched or linear polyalkenyl group.

  The polyalkenyl moiety may have a number average molecular weight of 200 to 3000, preferably 350 to 950.

In the present invention, suitable hydrocarbons or polymers used to form the polyalkenyl moiety during the formation of the acid anhydride include homopolymers, copolymers, or low molecular weight hydrocarbons. One class of such polymers includes polymers of ethylene and / or at least one C3-C28 alpha olefin (having the formula H ₂ C═CHR ¹ ), where R ¹ is a direct A chain or branched alkyl radical (containing 1 to 26 carbon atoms) and the polymer contains carbon-carbon unsaturation, preferably high levels of terminal ethenylidene unsaturation. Preferably, such a polymer comprises a copolymer of ethylene and at least one alpha olefin of the above formula, wherein R ¹ has 1 to 18 carbons, more preferably 1 to 8 carbons. Even more preferably, it is alkyl having 1 to 2 carbon atoms. Therefore, useful alpha olefin monomers and comonomers include, for example, propylene, butene-1, hexene-1, octene-1, 4-methylpentene-1, decene-1, dodecene-1, tridecene-1, tetradecene- 1, pentadecene-1, hexadecene-1, heptadecene-1, octadecene-1, nonadecene-1, and mixtures thereof (for example, a mixture of propylene and butene-1, etc.). Examples of such polymers include propylene homopolymers, butene-1 homopolymers, ethylene-propylene copolymers, ethylene-butene-1 copolymers, propylene-butene copolymers, etc., where the polymer comprises at least some Contains terminal and / or internal unsaturation. Preferred polymers are unsaturated copolymers of ethylene and propylene and ethylene and butene-1. The copolymer may contain a small amount (eg, 0.5-5 mol%) of a C4-C18 non-conjugated diolefin comonomer. However, the polymer preferably contains only alpha olefin homopolymer, copolymer of alpha olefin comonomer, and copolymer of ethylene and alpha olefin comonomer. The molar content of ethylene in the polymer used is preferably 0 to 80%, more preferably 0 to 60%. When propylene and / or butene-1 is used as a comonomer with ethylene, the ethylene content of such a copolymer is most preferably 15-50%, but may be higher or lower.

These polymers include an alpha olefin monomer, a mixture of alpha olefin monomers, or a mixture comprising ethylene and at least one C3-C28 alpha olefin monomer, and at least one metallocene (e.g., cyclopentadienyl transition metal compound). ) And an alumoxane compound can be prepared by polymerization in the presence of a catalyst system. By using this method, a polymer in which 95% or more of the polymer chains have ethenylidene type terminal unsaturation can be provided. The percentage of polymer chains exhibiting ethenylidene terminal unsaturation can be determined by FTIR spectroscopy, titration, or C ¹³ NMR. Copolymers of this latter type are characterized the formula POLY-C (R1) = CH2 , wherein, R ¹ is alkyl of C1～C26, alkyl preferably C1 - C18, more preferably C1~ C8 alkyl, most preferably C1-C2 alkyl (ie methyl or ethyl), POLY represents the polymer chain. The chain length of the R ¹ alkyl group will vary depending on the comonomer selected during the polymerization. A small amount of polymer chain may contain terminal ethenyl, i.e. vinyl unsaturation, i.e. POLY-CH = CH2, and part of the polymer contains internal monounsaturation, e.g. POLY-CH = CH (R1). Where R ¹ is as defined above. These terminal unsaturated copolymers can be prepared by known metallocene chemistry and are also described in US Pat. Nos. 5,498,809, 5,663,130, 5,705,577, It can also be prepared by the description of 5,814,715, 6,022,929, and 6,030,930.

Another useful class of polymers are polymers prepared by cationic polymerization such as isobutene and styrene. Common polymers of this class, has a butene content of 35 to 75 wt%, C4 refinery stream having isobutene content of 30 to 60 wt% of (C ₄ refinery stream), a Lewis acid catalyst (e.g. And polyisobutene obtained by polymerization in the presence of aluminum trichloride or boron trifluoride). A preferred monomer feed to produce poly-n-butene is a petroleum feedstream such as Raffinate II. These raw materials are disclosed in US Pat. No. 4,952,739 and the like. Polyisobutylene is the most preferred backbone because it is readily available by cationic polymerization from a butene stream (eg, using an AlCl ₃ or BF ₃ catalyst). Such polyisobutylenes generally contain residual unsaturation located along the chain in an amount of one ethylenic double bond per polymer chain. In a preferred embodiment, a polyisobutylene prepared from a pure isobutylene stream or a Raffinate I stream is utilized to prepare a reactive isobutylene polymer having a terminal vinylidene olefin. Preferably, these polymers, referred to as highly reactive polyisobutylene (HR-PIB), have a terminal vinylidene content of at least 65%, such as 70%, more preferably at least 80%, most preferably at least 85%. Have. The preparation of such polymers is described, for example, in US Pat. No. 4,152,499. HR-PIB is known and HR-PIB is commercially available under the trade names Glossopal ^™ (BASF) and Ultravis ^™ (BP-Amoco).

  The polyisobutylene polymers that can be employed are generally based on 400 to 3000 hydrocarbon chains. Methods for producing polyisobutylene are known. Polyisobutylene can be functionalized by free radical grafting using halogenation (eg, chlorination), thermal “ene” reaction, or catalyst (eg, peroxide), as shown below. Can be

  In order to produce (C), the hydrocarbon or polymer backbone is selected selectively at a carbon-carbon unsaturation site on the polymer or hydrocarbon chain, or any of the above three processes or combinations thereof. It may be used in any order and randomly functionalized with a carboxylic anhydride generating moiety along the chain.

  The steps of reacting polymeric hydrocarbons with unsaturated carboxylic acid anhydrides and the preparation of derivatives of such compounds are described in US Pat. Nos. 3,087,936, 3,172,892, and 3,215. No. 3,707, No. 3,231,587, No. 3,272,746, No. 3,275,554, No. 3,381,022, No. 3,442,808, No. 3,565,804, 3,912,764, 4,110,349, 234,435; 5,777,025, 5,891, No. 953, as well as EP0382450B1, CA-1,335,895, and GB-A-1,440,219. Using a halogen-assisted functionalization (eg chlorination) process or a thermal “ene” reaction, a functional moiety or agent, ie an acid, on the polymer or hydrocarbon chain, mainly at the carbon-carbon unsaturation site, also referred to as ethylene or olefin unsaturation. By reacting the polymer or hydrocarbon under conditions such that the anhydride is added, the polymer or hydrocarbon may be functionalized with a carboxylic anhydride moiety.

  60-250 ° C., preferably 110-160 ° C., for example 120-140 ° C., 0.5-10 hours, preferably 1-7 hours, passing chlorine or bromine through the polymer, based on the weight of the polymer or hydrocarbon Selective functionalization can be achieved by halogenating (eg, chlorinating or brominating) the unsaturated alpha olefin polymer to 1-8 wt%, preferably 3-7 wt% chlorine or bromine. The halogenated polymer or hydrocarbon (hereinafter “backbone”) then contains the desired number of monounsaturated carboxylic reactants per mole of main chain halogenated in the resulting product. A sufficient amount of a monounsaturated reactant (e.g., a monounsaturated carboxylic acid reactant) capable of adding the required number of functional moieties to the backbone and 100-250 ° C, usually 180 The reaction is carried out at a temperature of from C to 235 C for 0.5 to 10 hours, for example 3 to 8 hours. Alternatively, the backbone and the monounsaturated carboxylic reactant are mixed and heated while adding chlorine to the heated thermal material.

  Chlorination usually helps to increase the reactivity of the starting olefin polymer with the monounsaturated functional reactants, but some polymers or hydrocarbons intended for use in the present invention, especially high Preferred polymers or hydrocarbons with end bond content and reactivity are not necessary. Therefore, preferably, the backbone and the monounsaturated functional reactant (carboxylic acid reactant) are contacted at elevated temperatures, causing an initial thermal “ene” reaction. The ene reaction is known.

  The hydrocarbon or polymer backbone can be functionalized by randomly adding functional moieties along the polymer backbone in a variety of ways. For example, the polymer may be grafted in solution or in solid form with a monounsaturated carboxylic reactant in the presence of a free radical initiator as previously described. When carried out in solution, grafting occurs at an elevated temperature of 100-260 ° C, preferably 120-240 ° C. Preferably, free radical initiated grafting is carried out in a mineral lubricating oil solution containing, for example, 1-50% by weight, preferably 5-30% by weight of polymer, based on the initial total oil solution.

  Usable free radical initiators include peroxides, hydroperoxides, and azo compounds, which preferably have a boiling point greater than 100 ° C. and are thermally decomposed and released in a grafting temperature range that provides free radicals. The group is given. Representative examples of these free radical initiators include azobutyronitrile, 2,5-dimethylhex-3-ene-2,5-bis-tertiary butyl peroxide, and dicumene peroxide. Initiators, when used, are typically in an amount of 0.005% to 1% by weight, based on the weight of the reaction mixture. Typically, the aforementioned monounsaturated carboxylic reactant material and free radical initiator are used in a weight ratio of 1.0: 1 to 30: 1, preferably 3: 1 to 6: 1. . Grafting is preferably performed under an inert atmosphere, such as a nitrogen seal. The resulting grafted polymer is characterized by having carboxylic acid (or derivative) moieties randomly attached along the polymer chain, but of course, some of the polymer chains are ungrafted. It is understood that The free radical grafting described above can also be used for other polymers and hydrocarbons used in the present invention.

  Preferred monounsaturated reactants used to functionalize the backbone are: (i) monounsaturated C4-C10 dicarboxylic acid ((a) the carboxyl group is vicinyl (ie, located on an adjacent carbon atom) And (b) at least one of the adjacent carbon atoms, preferably both are part of monounsaturation); (ii) a derivative of (i) (eg an acid anhydride or (I) a C1-C5 alcohol-derived mono- or diester); (iii) a monounsaturated C3-C10 monocarboxylic acid (the carbon-carbon double bond is conjugated to a carboxy group, i.e., -C = C- Mono- and dicarboxylic acid materials, including (iv) (iii) derivatives (eg, C1-C5 alcohol-derived mono- or diesters of (iii)); An acid or acid inducer. Mixtures of monounsaturated carboxylic acid materials (i)-(iv) can also be used. By reaction with the main chain, the monounsaturation of the monounsaturated carboxylic reactant is saturated. Thus, for example, maleic anhydride becomes main chain substituted succinic anhydride and acrylic acid becomes main chain substituted propionic acid. Examples of such monounsaturated carboxylic reactants include fumaric acid, itaconic acid, maleic acid, maleic anhydride, chloromaleic acid, chloromaleic anhydride, acrylic acid, methacrylic acid, crotonic acid, cinnamic acid, And lower alkyl (eg C1-C4 alkyl) acid esters such as methyl maleate, ethyl fumarate, and methyl fumarate.

  In order to provide the necessary functionality, the monounsaturated carboxylic reactant, preferably maleic anhydride, is typically from an equimolar amount to a 100% by weight excess based on the moles of polymer and hydrocarbon. Used in an amount in the range, preferably in the range of 5-50% by weight excess. Unreacted excess monounsaturated carboxylic reactant may be removed from the final dispersant product, if desired, for example by stripping, usually performed under vacuum conditions.

Additives (Co-Additives)
The lubricating oil composition of the present invention may further contain an additional additive different from (B) and (C). Such additional additives include, for example, ashless dispersants, other metal detergents, antiwear agents (eg, zinc dihydrocarbyl dithiophosphate, antioxidants, and anti-emulsifiers. Ashless dispersants are necessary. Sometimes it is not.

  Although not essential, it is preferred to prepare one or more additive packages or additive concentrates, whereby additives (B) and (C) are simultaneously added to the base oil to produce a lubricating oil composition. can do. Solvent or mixing with some heating may facilitate dissolution of the additive package in the lubricating oil, but is not essential. The additive package typically provides the appropriate concentration when the additive package is used in combination with a predetermined amount of base oil and / or performs the intended function in the final composition. Prepared to contain an appropriate amount of additives. Thus, according to the present invention, additives (B) and (C), along with other suitable additives, are mixed with a small amount of base oil or other compatible solvent, for example 2 on an additive package basis. Additive packages can be produced that contain from 5 to 90% by weight, preferably from 5 to 75% by weight, most preferably from 8 to 60% by weight of the active ingredient of the additive in the appropriate proportions, the rest being base oil.

  The final composition as a trunk piston engine oil typically comprises an additive package of 30% by weight, preferably 10-28% by weight, more preferably 12-24% by weight, with the remainder being base oil. Good. The trunk piston engine oil may have a composition TBN (using ASTM D2896) of 20-60, for example 30-55. For example, it may be 40-55, or 35-50.

<Example>
The present invention is illustrated by the following examples, but is not limited thereto.

(component)
The following ingredients were used:
Ester base stock (A1)
Polyol ester (PRIOLUBE® 3970). Trimethylolpropane ester with C8 to C10 fatty acids. It has a viscosity of 4.4 mm ² s ⁻¹ at 100 ° C. Formerly made by Croda Lubricants;
Polymer ester (KETJENLUBE® 115). Copolymer form of alpha olefin and dicarboxylic acid dibutyl ester having an average molecular weight of about 1400.
Base stock (A2)
Group I oil ((XOMAPE 600) (for comparison)
Group II oil (RLOP 600)
Group III oil (YUBASE 8)
Items in parentheses are product names.
Cleaning agent (B)
Calcium alkyl salicylate (BI 8.0)
Calcium alkyl salicylate (BI 3.0)
Basicity index in parentheses
PIBSA (C)
Polyisobutene succinic anhydride derived from polyisobutene having a number average molecular weight of 950
HFO
Heavy oil (ISO-F-RMK 380)

(Trunk piston ship engine lubricating oil (TPEO))
Those selected from the above ingredients were mixed to obtain various TPEOs. Some are examples of the present invention and others are comparative examples for comparison. The composition of TPEO tested with each HFO is shown in mass% in the table in the “Results” column.

(test)
The asphaltene dispersibility of light scattering trunk piston ship engine lubricant (TPEO's) samples was evaluated using light scattering according to the Focus Beam Reflection Method (FBRM), which is an asphaltene agglomeration and even “black sludge” Predict the generation of

FBRM test method is disclosed in the 7th Marine Technology International Symposium, which was held in Tokyo on October 24-28, 2005 ^{(the 7 th International Symposium on Marine} Engineering, Tokyo, 24 th -28 th October 2005), “The Benefits of Salicylate Detergents in TPEO Applications with Variety of the Benefits of Salicylate Detergents in TPEO Applications in the Conference Proceedings”. The details are further disclosed in the CIMAC conference, which was held in Vienna on May 21 to 24, 2007 (the CIMAC Congress, Vienna, 21 st -24 th May 2007), the conference Abstracts (the Congress Proceedings) , "Meeting the Challenge of New Fluids for the Lubrication of Medium Speed Marine Aids-Aged in the United States" It was. In the latter article, asphaltenes predict the performance of lubricating systems based on base stocks containing more or less than 90% saturates and more or less than 0.03% sulfur by using the FBRM method. It is disclosed that quantitative results can be obtained with respect to the dispersibility of The relative performance predictions obtained by FBRM were confirmed by engine tests on marine diesel engines.

  The FBRM probe includes a fiber optic cable through which laser light passes to reach the probe tip. At the tip, the lens collects the laser light at a small point. The lens is rotated so that the collected beam scans the circumference between the probe window and the sample. As the particles pass through the window, they traverse the scan path, resulting in backscattered light from the individual particles.

  The scanning laser beam is much faster than the particles; this means that the particles are effectively static. When the collected beam reaches one end of the particle, the amount of backscattered light increases; when the collected beam reaches the other end of the particle, the amount will decrease.

  The instrument measures the time of increased backscatter. The time of backscatter from one particle is multiplied by the scanning speed, and the result is obtained as a distance or a chord length. The code length is a straight line between any two points at the end of the particle. This is expressed as a code length distribution, which is a graph of the number of code lengths (particles) measured as a function of code length in the μm dimension. Since measurements are performed in real time, distribution statistics can be calculated and tracked. FBRM typically measures tens of thousands of codes per second, resulting in a reliable number-code length distribution. This method absolutely measures the particle size distribution in asphaltene particles.

  A Lasentec D600L type Focused Beam Reflection Probe (FBRM) was supplied by Mettler Toledo, Leicester, UK. This apparatus was used in a configuration that gave a particle size resolution of 1 μm to 1 mm. Data from the FBRM can be obtained by several methods. Investigations have suggested that an average count per second can be used for quantitative determination of asphaltene dispersion. This value is a function of both average size and aggregation level. In this application, the average measurement rate (over all size ranges) was measured with a measurement time of 1 second per sample.

  The TPEO sample was heated to 60 ° C. and stirred at 400 rpm; when the temperature reached 60 ° C., an FBRM probe was inserted into the sample and measurements were taken for 15 minutes. An aliquot of heavy oil (10% w / w) was added to TPEO while stirring (400 rpm) using a 4-blade stirrer. After the measurement rate reached the equilibrium value (typically overnight), the average number of measurements per second was obtained.

(result)
The results of the light scattering FBRM test are summarized in the table below, where a smaller particle count indicates better performance.

  The comparative example is shown as “Ref”.

Ｒｅｆ３及びＲｅｆ４は、米国特許出願公開Ｎｏ．２０１１／０３１９３０４ Ａ１“３０４”による例である。Ｒｅｆ４（エステルの単独使用）により、“３０４”による示唆が確認された。Ｒｅｆ５（ＰＩＢＳＡの単独使用）により、“５９４”による示唆が確認された。例１−３により、ＰＩＢＳＡとエステルとの相乗効果が確認された。 (Table 1)
Each TPEO tested had 40 BN, 1.23 wt% (calcium units) BI salicylate of 8.0, and 0.24 wt% (calcium complete) BI of 3 0.0 calcium salicylate and the same amount of Zn and the same amount of silicone antifoam. The remaining components of the final oil composition are shown in the table below.

Ref3 and Ref4 are U.S. Patent Application Publication Nos. This is an example according to 2011/0319304 A1 “304”. The suggestion by “304” was confirmed by Ref4 (single use alone). The suggestion by “594” was confirmed by Ref5 (single use of PIBSA). Example 1-3 confirmed the synergistic effect of PIBSA and ester.

(Table 2)
Each tested TPEO has 40 BN, 0.75% by weight (calcium equivalent) BI of 8.0 salicylate and 0.68% by weight (calcium equivalent) BI of 3.0. It contained some calcium salicylate and contained the same amount of Zn. The remaining components of the final oil composition are shown in the table below.

  This result shows that the change in PIBSA and ester content rate affects performance: In Example 4-8, the PIBSA content is constant and the ester content is gradually In Examples 9-13, the ester content is constant and the PIBSA content is gradually increasing. Example 14 demonstrates that the applicability of the present invention to Group III base oils exceeds that of Ref 6 (Group I oil), and Example 15 illustrates the applicability of the present invention to esters other than Priolube 3970. ing.

(Table 3)
Each TPEO used has 30 BN, 0.56% by mass (calcium equivalent) BI of 8.0 and 2.01% by mass (calcium equivalent) BI of 3.0. It contained calcium salicylate and contained the same amount of Zn. The remaining components in the final oil composition are shown in the table below.

  This result shows that the effect of the present invention is exhibited even in a low BN TPEO.

Claims (20)

A trunk piston marine engine lubricating oil composition for improving asphaltene handling in use during engine operation when fueled by heavy oil,
(A) oil-soluble ester base stock (A1) or
More than 0.1% by weight and less than 90% by weight, preferably 1-85% by weight of the oil-soluble ester base stock (A1) and the remaining oil of lubricating viscosity of 50% by weight or more, 90% or more saturates And a large amount of lubricating viscosity oil comprising a base stock containing 0.03% or less of sulfur or a mixture thereof (A2);
(B) a small amount of oil-soluble metal detergent;
(C) a small amount of at least one polyalkenyl group of more than 0.1% by weight and less than 10% by weight, preferably more than 0.5% by weight and less than 8% by weight, derived from a polyalkene having a number average molecular weight of 200 to 3000 An oil-soluble polyalkenyl substituted carboxylic anhydride, and
Or produced by mixing,
Lubricating oil composition. A lubricating oil composition according to claim 1,
When the base stock (A2) is present in an oil of lubricating viscosity, the base stock or mixture thereof containing 90% or more of saturates and 0.03% or less of sulfur is more than 60% by weight, preferably 70%. Lubricating oil composition containing more than wt%, more preferably more than 80 wt%, most preferably more than 90 wt%. The lubricating oil composition according to claim 1 or 2,
A base stock (A2), if present, is a Group II, Group III, or Group IV base stock, preferably a Group II base stock lubricating oil composition. The lubricating oil composition according to any one of claims 1 to 3,
The lubricating oil composition, wherein the metal detergent (B) is a metal hydrocarbyl substituted hydroxybenzoate detergent. A lubricating oil composition according to claim 4, wherein
The lubricating oil composition, wherein the metal detergent (B) is a calcium alkyl salicylate detergent. The lubricating oil composition according to claim 4 or 5, wherein
The lubricating oil composition, wherein the metal detergent (B) is substituted by C9 to C30 alkyl. The lubricating oil composition according to claim 4 or 5, wherein
The lubricating oil composition in which the metal detergent (B) is substituted by C20 or higher alkyl. The lubricating oil composition according to any one of claims 1 to 7,
The lubricating oil composition, wherein the polyalkenyl substituent in the polyalkenyl-substituted carboxylic anhydride (C) has 8 to 400 carbon atoms, such as 12 to 100 carbon atoms, particularly 16 to 64 carbon atoms. The lubricating oil composition according to any one of claims 1 to 8,
The lubricating oil composition, wherein the number average molecular weight of the polyalkenyl substituent in the polyalkenyl-substituted carboxylic anhydride (C) is 350 to 1000, such as 500 to 1000. A lubricating oil composition according to any one of claims 1 to 9,
The lubricating oil composition, wherein the polyalkenyl-substituted carboxylic acid anhydride (C) is succinic anhydride. A lubricating oil composition according to claim 10, comprising:
The lubricating oil composition, wherein the succinic anhydride is polybutene succinic anhydride. The lubricating oil composition according to any one of claims 1 to 11,
A lubricating oil composition wherein the ester base stock (A1) is present in an amount of 10 to 90% by weight, such as 20 to 90% by weight, for example 30 to 90% by weight. The lubricating oil composition according to any one of claims 1 to 12,
A lubricating oil composition having an ester base stock (A1) having a kinematic viscosity at 100 ° C. of ^{2 to 10} mm ² s ⁻¹ . The lubricating oil composition according to any one of claims 1 to 13,
The ester base stock (A1) is a lubricating oil composition which is a polyol ester base stock. The lubricating oil composition according to any one of claims 1 to 14, further comprising a heavy oil component. (I) supplying fuel to the engine with heavy oil;
(Ii) lubricating an engine crankcase with the oil composition according to any one of claims 1 to 15;
Method of operating a trunk piston medium speed compression ignition marine engine including A method for dispersing asphaltenes in a trunk piston ship lubricating oil composition during lubrication of the combustion chamber surface of a medium speed compression ignition ship engine and during operation of the engine, comprising:
(I) providing a composition according to any of claims 1 to 15;
(Ii) supplying a composition into the combustion chamber;
(Iii) supplying heavy oil into the combustion chamber;
(Iv) burning heavy oil in the combustion chamber;
Including methods. The method according to claim 17, comprising the steps of:
Dispersion of asphaltenes is a method that is measured using a focused beam reflection method (FBRM).   Use of component (B) in combination with component (C) in the amount specified and described in any of claims 1 to 15 in a trunk piston marine lubricating oil composition for medium speed compression ignition marine engines Wherein the composition comprises a large amount of oil of lubricating viscosity (A) as defined in claim 1 and during operation of the engine fueled with heavy oil and during its lubrication, the composition causes the base stock (A2 Uses that provide comparable or improved asphaltene handling as compared to corresponding oils that are Group 1 basestocks. The use as claimed in claim 19, wherein
The use of asphaltene handling during engine operation is measured using the Focused Beam Reflection Method (FBRM).