JP2017014505A - Additive package for marine engine lubrication - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce or overcome problems stability problems evidenced by gel or phase separation in certain combinations of salicylate and sulfonate detergents.SOLUTION: An additive package for a two- or four-stroke marine engine lubricant comprises an oil of lubricating viscosity, a salicylate detergent and a sulfonate detergent in a ratio of 90/10 to 10/90 (expressed as mmol of soap), and (C) 1 to 10 mass% of a hydrocarbylphenol-aldehyde condensate.SELECTED DRAWING: None

Description

The present invention relates to lubrication of two-stroke and four-stroke marine diesel internal combustion engines, i.e., the former commonly referred to as crosshead engines and the latter referred to as trunk piston engines. Each lubricant suitable for these applications is commonly known as marine diesel cylinder lubricant ("MDCL") and trunk piston engine oil ("TPEO").

BACKGROUND OF THE INVENTION A crosshead engine is a low speed engine having a high power to ultra high power range. This engine has two separately lubricated parts: a piston / cylinder assembly lubricated with high loss oil (MDCL) with full loss lubrication; and a crank lubricated with a low viscosity lubricant, usually called system oil Includes axis.
Trunk piston engines can be used in marine, power generation and railway traction applications and are faster than crosshead engines. A single lubricant (TPEO) is used to lubricate the crankcase and cylinder. All major moving parts of the engine, ie main and big end bearings, camshaft and valve gear, are lubricated using a pumped circulation system. The cylinder liner is lubricated partly by splash-type lubrication and partly by circulation system oil, which reaches the cylinder wall through the hole in the piston skirt via the connecting rod and the gudgeon pin.

Marine lubricants are routinely blended with metal detergent additives. A practical problem of using detergents for this purpose is that certain combinations of salicylate detergents and sulfonate detergents exhibit stability problems that are evidenced by gel or phase separation.
The object of the present invention is to reduce or overcome such problems.

Summary of the Invention It has now been found that the above problems can be overcome with additives exemplified by methylene bridged alkylphenols.
Accordingly, the present invention, in one aspect, comprises a small amount of an oil of lubricating viscosity and a large amount of (A) an overbased metal hydroxybenzoate detergent additive and (B) an overbased metal sulfonate detergent additive; C) Additive package for a two-stroke or four-stroke marine engine lubricating oil composition comprising an oil-soluble hydrocarbylphenol-aldehyde condensate additive in an amount ranging from 1 to 10, preferably 3 to 5% by weight. The ratio of (A) to (B) expressed as millimoles of soap is in the range of 90:10 to 10:90, preferably 80:20 to 25:75; and the additive package is An additive package is provided using ASTM D2896, preferably having a TBN of 100-450, more preferably 150-400.

In a second embodiment, a two-stroke or four-stroke marine engine lubricating oil composition comprising a large amount of oil of lubricating viscosity blended with a small amount of the additive package, wherein the two-stroke engine composition is Compositions are provided having a TBN of 10 to 120, preferably 40 to 100 using ASTM D2896, and having a TBN of 25 to 60 using ASTM D2896 in the case of a four-stroke engine composition.
The additive package is used at a treatment rate of 15 to 30% by mass to produce a two-stroke engine composition, and the additive package is 10 to 20% by mass to produce a four-stroke engine composition. It is preferable to use at a treatment rate.
The lubricating oil composition contains 0.15-1.5 wt% oil-soluble hydrocarbylphenol-aldehyde condensate additive for 2-stroke engine compositions and 0.1-1 wt% oil-soluble for 4-stroke engines Preferably, a hydrocarbyl phenol-aldehyde condensate additive is included.
In a further aspect, the invention provides:
In a marine diesel cylinder lubricant containing the additives (A) and (B) in the above ratio, 1 to 10 for improving the stability of the additives (A) and (B) in the lubricant Use of a mass% additive (C); and a method of lubricating a crosshead marine diesel engine, wherein the composition of the above aspect of the invention is supplied to the piston / cylinder of the engine during engine operation. Including methods.

As used herein, the following terms and expressions are used and when used, have the meaning ascribed to them below.
“Active ingredient” or “(ai)” represents an additive material that is not a diluent or solvent;
“Contains” or any similar term specifies the presence of a specified feature, step, or integer or component, but the presence or addition of one or more other features, steps, integers, components, or groups thereof The expression “consisting of” or “consisting essentially of” or like expressions may be encompassed by the term “including” or like terms. Here, “consisting essentially of” allows inclusion of substances that do not materially affect the characteristics of the composition to which it is applied;
“Hydrocarbyl” means a carbon atom directly attached to the rest of the molecule and a substituent or group having predominantly hydrocarbon character (eg, an alkyl group). Heteroatoms may be present provided that they do not substantially change the hydrocarbon character of the group;
“Major amount” means 40 or 50% by weight or more of the composition, preferably 60% by weight or more, more preferably 70% by weight or more, most preferably 80% by weight or more;
“Minor amount” means less than 50%, preferably less than 40%, more preferably less than 30%, most preferably less than 20%, most preferably less than 10% by weight of the composition;
“TBN” means the total base number as measured by ASTM D2896.

Furthermore, in this specification, when using and when using,
“Calcium content” is measured by ASTM 4951;
“Phosphorus content” is measured by ASTM D5185;
“Sulfate ash content” is measured by ASTM D874;
"Sulfur content" is measured by ASTM D2622;
“KV100” means kinematic viscosity measured by ASTM D445 at 100 ° C.
Also, it will be appreciated that various components used, not only essential but also optimal and customary, may react under the conditions of formulation, storage or use, and the present invention may be obtained as a result of any such reaction. A product that can or is obtained is also provided.
Further, it will be appreciated that any upper and lower amount, range and ratio specified herein may be combined independently.

DETAILED DESCRIPTION OF THE INVENTION The features of the present invention are discussed in further detail below.
<Oil of lubricating viscosity>
The lubricant composition contains a large proportion of oil of lubricating viscosity. The viscosity of the lubricating oil can range from a light cut mineral oil to a heavy lubricating oil. Generally, the viscosity of the oil ranges from ² to 40, such as from 3 to 15 mm ² / sec when measured at 100 ° C., and has a viscosity index of from 80 to 100, such as from 90 to 95. The lubricating oil may constitute more than 60%, typically more than 70% by weight of the composition.
Natural oils include animal and vegetable oils (eg, castor oil, lard oil); liquid petroleum and hydrorefined, solvent-treated or acid-treated mineral oils of the paraffin, naphthalene and mixed paraffin-naphthalene type. Oils of lubricating viscosity derived from coal or shale also serve as useful base oils.
Synthetic lubricating oils include hydrocarbon oils and halo-substituted hydrocarbon oils such as polymerized and copolymerized olefins (e.g. polybutylene, polypropylene, propylene-isobutylene copolymer, chlorinated polybutylene, poly (1-hexene), poly (1-octene). ), Poly (1-decene)); alkylbenzenes (eg, dodecylbenzene, tetradecylbenzene, dinonylbenzene, di (2-ethylhexyl) benzene); polyphenyls (eg, biphenyl, terphenyl, alkylated polyphenols); Examples include alkylated diphenyl ethers and alkylated diphenyl sulfides, and derivatives, analogs and homologues thereof.

Alkylene oxide polymers and interpolymers and derivatives thereof whose terminal hydroxyl groups have been modified by esterification, etherification, etc. constitute another class of known synthetic lubricating oils. These include polyoxyalkylene polymers prepared by polymerization of ethylene oxide or propylene oxide, and alkyl and aryl ethers of polyoxyalkylene polymers (e.g., methyl-polyisopropylene glycol ether having a molecular weight of 1000 or a molecular weight of 1000-1500. And the monocarboxylic and polycarboxylic acid esters thereof, such as tetraethylene glycol acetate, mixed C ₃ -C ₈ fatty acid esters and C ₁₃ oxo acid diesters.
Another suitable class of synthetic lubricating oils are dicarboxylic acids (e.g., phthalic acid, succinic acid, alkyl succinic acid and alkenyl succinic acid, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, linoleic acid. Dimers, malonic acids, alkylmalonic acids, alkenylmalonic acids) and esters of various alcohols (eg, butyl alcohol, hexyl alcohol, dodecyl alcohol, 2-ethylhexyl alcohol, ethylene glycol, diethylene glycol monoether, propylene glycol). Specific examples of the ester include dibutyl adipate, di (2-ethylhexyl) sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, didecyl phthalate, sebacin Examples include dieicosyl acid, 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.

Esters useful as synthetic oils include those made from C ₅ -C ₁₂ monocarboxylic acids and polyols and polyol esters such as neopentyl glycol, trimethylolpropane, pentaerythritol, dipentaerythritol and tripentaerythritol. included.
Silicon-based oils such as polyalkyl-, polyaryl-, polyalkoxy- or polyallyloxysilicone oils and silicate oils constitute another useful class of synthetic lubricants; such oils include tetraethyl silicate, tetraisopropyl Silicate, tetra- (2-ethylhexyl) silicate, tetra- (4-methyl-2-ethylhexyl) silicate, tetra- (p-tert-butyl-phenyl) silicate, hexa- (4-methyl-2-ethylhexyl) di Mention may be made of siloxanes, poly (methyl) siloxanes and poly (methylphenyl) siloxanes. Other synthetic lubricating oils include liquid esters of phosphorus-containing acids (eg, tricresyl phosphate, trioctyl phosphate, diethyl ester of decylphosphonic acid) and polymeric tetrahydrofurans.
Unrefined oil, refined oil and re-refined oil can be used for the lubricant of the present invention. Unrefined oils are those obtained directly from natural or synthetic sources without further purification. For example, shale oil obtained directly from retort harvesting operations; petroleum oil obtained directly from distillation; or ester oil obtained directly from esterification and used without further purification is an unrefined oil.

The American Petroleum Institute (API) publication “Engine Oil Licensing and Certification System” (Industry Services Department, 14th Edition, December 1996, Addendum 1, December 1998) Base stock is classified as follows.
a) Group I base stock contains less than 90% saturates and / or more than 0.03% sulfur and has a viscosity index of 80 to less than 120 using the test method specified in Table E-1.
b) Group II base stock contains 90% or more of saturates and 0.03% or less of sulfur and has a viscosity index of 80 or more and less than 120 using the test method specified in Table E-1.
c) Group III base stock contains 90% or more of saturates and 0.03% or less of sulfur and has a viscosity index of 120 or more using the test method specified in Table E-1.
d) Group IV base stock is polyalphaolefin (PAO).
e) Group V base stock includes all other base stocks not included in Group I, II, III, or IV.
The analysis method of base stock is shown in the table below.

表E-1

Table E-1

The present invention preferably includes such base stocks of the above oils containing, for example, greater than 90% saturates and less than 0.03% sulfur as oils of lubricating viscosity, such as Groups II, III, IV or V. They also include hydrocarbon-derived base stocks synthesized by 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 generally require further processing to serve as base oils. For example, they can be hydroisomerized; hydrocracked and hydroisomerized; dewaxed; or hydroisomerized and dewaxed by methods well known in the art. Syngas, for example, when the base stock can be referred to as a gas-to-liquid (“GTL”) base oil, is obtained from a gas such as natural gas or other gaseous hydrocarbons by steam reforming; Biomass-to-liquid (“BTL” or “BMTL”) base oil, when referred to as biomass gasification; or base stock from coal-to-liquid (“CTL”) base oil Can be produced from coal gasification.
Preferably, the oil of lubricating viscosity in the present invention contains 50% by mass or more of the base stock. The oil may contain 60% by weight or more, for example 70, 80 or 90% by weight or more of the base stock or mixtures thereof. The oil of lubricating viscosity may be substantially all of the base stock or a mixture thereof.

<Additives (A) and (B)>
Each of these is a detergent, i.e. an additive that reduces the formation of deposits in the engine, such as hot varnish and lacquer deposits; Can be held. Detergents are based on metal “soaps”, ie metal salts of acidic organic compounds, sometimes called surfactants.
The detergent includes a polar head and a long hydrophobic tail. A detergent that has been neutralized as an outer layer of a metal base (e.g., carbonate) micelle that includes a large amount of metal base by reacting excess metal compound, e.g., oxide or hydroxide, with an acidic gas such as carbon dioxide. An overbased detergent containing is obtained.
The detergent is an alkali metal or alkaline earth metal additive such as an overbased oil-soluble or oil-dispersible calcium, magnesium, sodium or barium salt of a surfactant preferably selected from acids, the overbase Is stabilized by oil-insoluble metal salts, such as carbonates, basic carbonates, acetates, formates, hydroxides or oxalates, which are stabilized in oily diluents by oil-soluble salts of surfactants. Brought about. The metal of the oil-soluble surfactant salt may be the same as or different from the metal of the oil-insoluble salt. Whether it is an oil-soluble salt or an oil-insoluble salt, the metal is preferably calcium.
The TBN of the detergent can be low, i.e. less than 50 mg KOH / g, moderate, i.e. 50-150 mg KOH / g, or high, i.e. above 150 mg KOH / g, as measured by ASTM D2896. Preferably TBN is moderate or high, i.e. above 50TBN. More preferably, the TBN is at least 60 mg KOH / g, more preferably at least 100 mg KOH / g, more preferably at least 150 mg KOH / g, and up to 500 mg KOH / g, for example up to 350 mg KOH / g, as measured by ASTM D2896. is there.
In detergent (A), the surfactant is selected from hydroxybenzoic acid, a specific example is salicylic acid, and the salt is salicylate. Salicylate detergents are well known in the art.
In detergent (B), the surfactant is selected from sulfonic acids and the salt is a sulfonate. Sulfonate detergents are also well known in the art.
Detergents that can be used are those that are hydrocarbyl (eg alkyl) substituted, as is well known in the art.
As noted above, the ratio of (A) to (B) expressed as millimoles of soap is in the range of 90:10 to 10:90. Examples of the upper limit of the range include 80:20 and 75:25. An example of the lower limit of the range is 25:75. The lower limit can be given by combining the upper and lower limits independently.

<Additive (C): for example, methylene-bridged alkylphenol ("MBAP")>
These are well known in the art and may include oil-soluble mixtures of oxyalkylated hydrocarbyl phenol condensates. Where the oxyalkyl group prepared from the phenol functional group has the formula — (R′O) _n —, where R ′ is an ethylene, propylene or butylene group; and n is independently from 0 to Less than 45 mol%, preferably less than 30 mol% of the phenol functionality of the condensate is not oxyalkylated; more than 55 mol% of the phenol functionality of the condensate is monooxyalkylated.
The condensate can be represented by the following general structural formula.

In the formula:
x is 1 to 50, preferably 1 to 40, more preferably 1 to 30;
R ¹ and R ² are H, a hydrocarbyl group having 1 to 12 carbon atoms, or a hydrocarbyl group having 1 to 12 carbon atoms and at least one heteroatom; and
R is a hydrocarbyl group having 9 to 100, preferably 9 to 70, more preferably 9 to 50 carbon atoms.
EP-A-2,374,866 describes the condensate in more detail. MBAP constitutes one embodiment of the condensate.
As mentioned above, (C) is present in an amount ranging from 1 to 10% by weight, preferably from 3 to 5% by weight. Examples of the lower range may include 1 to 7% by mass and 1 to 5% by mass.
For the avoidance of doubt, it is clearly stated that the MBAP used in the present invention may be capped or uncapped.

<Ship lubricant>
Marine diesel cylinder lubricant (MDCL)
The MDCL can utilize a 10-35 wt% concentrate, preferably 13-30 wt%, most preferably 16-24 wt% concentrate or additive package, with the remainder being base stock. The MDCL preferably comprises an oil having a lubricating viscosity of at least 50% by weight, more preferably at least 60% by weight, more preferably at least 70% by weight, based on the total weight of the MDCL. Preferably, the MDCL has a TBN (using ASTM D2896) with a composition of 10-100, such as 70-100 or 40-100, preferably 60-90, more preferably 70-80.
Examples of typical proportions of additives in MDCL include the following.

Trunk piston engine oil (TPEO)
The TPEO can utilize a concentrate or additive package of 7-35% by weight, preferably 10-28% by weight, more preferably 12-24% by weight, the rest being base stock. Preferably, the TPEO has a TBN (using ASTM D2896) on the composition of 25-60, such as 25-55.
The following can be mentioned as typical proportions of additives in TPEO.

As used herein, the term “oil-soluble” or “oil-dispersible” does not necessarily mean that the compound or additive can be soluble, soluble, miscible or suspended in oil in all proportions. However, these terms mean that the compound or additive is soluble or stable dispersible in the oil to a degree sufficient to exert their intended effect in the environment in which the oil is utilized. . Furthermore, if necessary, further incorporation of other additives may allow higher levels of incorporation of specific additives.
The lubricant composition of the present invention comprises defined individual (ie, individual) components that may or may not remain chemically the same before and after mixing.
Although not required, it may be desirable to prepare one or more additive packages or concentrates containing the additives, thereby simultaneously adding the additives to the oil of lubricating viscosity to form a lubricating oil composition. . Mixing with a solvent and with gentle heating can facilitate the dispersion of the additive package into the oil of lubricating viscosity, but this is not essential. In general, the additive package should contain the additive in an amount suitable to provide the desired concentration and / or perform the intended function in the final formulation when the additive package is used with the base lubricant. Will be blended.
Thus, the additive is mixed with a small amount of base oil or other compatible solvent along with other desirable additives, for example 2.5-90, preferably 5-75, most preferably 8 based on the additive package. Additive packages containing the active ingredient in an appropriate proportion of additives of ˜60% by weight, the remainder being base oil can be formed.
The final formulation typically contains about 5-40% by weight additive package with the remainder being base oil.

Examples The present invention is illustrated by the following examples, but the present invention is not limited thereto.
<Stability test method>
Various proportions of calcium salicylate detergent (basicity index 1.35) and calcium sulfonate detergent (basicity index 22.0) in a single step with the help of stirrer and hotplate, 75% with 1% diluent oil Mix at 30 ° C. for 30 minutes. This gave a series of mixtures.
Each resulting mixture was poured into a graduated glass stability tube and tested at room temperature and 60 ° C. for 12 weeks.
Each week, the stability tube was visually inspected for gel formation, phase separation, amount of sediment falling to the tube bottom, and turbidity as evidence of additive instability.
The test was performed on a mixture containing methylene bridged dodecylphenoxyethanol (uncapped “MBAP”) and a mixture containing no.
<Result>

キー：
OK：添加剤の安定性問題観察されず
ゲル/相分離ⁿ：添加剤不安定性(相分離よりひどいゲル形成)
数：安定性性能を観察及び報告した週数(最初の数は室温試験；2番目の数は60℃試験)

Key:
OK: Additive stability not observed, gel / phase separation ⁿ : Additive instability (gel formation worse than phase separation)
Number: Weeks in which stability performance was observed and reported (first number at room temperature test; second number at 60 ° C test)

The above data shows the following.
1. At 90/10 ratio, no stability problem was observed even in the absence of MBAP.
2. At 75/25 ratio, stability problems are observed in the absence of MBAP; room temperature test shows no stability problems at 1, 3 and 5 wt% MBAP; 60 ° C test is 1 and 3 The mass% MBAP showed improvement, and 5% by mass MBAP showed no problem.
3. At 50/50 ratio, problems are observed in the absence of MBAP and 1% by weight MBAP; 3% by weight MBAP test provides some improvement; 5% by weight MBAP test is 60 ° C. even at room temperature But it showed no stability problems.
4. At 25/75 ratio, problems are observed in the absence of MBAP; with 1 and 3 wt% MBAP, room temperature results are worse than 60 ° C results; 5 wt% MBAP test is 60 ° C even at room temperature But it showed no stability problems.

Claims (8)

An additive package for a two-stroke or four-stroke marine engine lubricating oil composition comprising:
A small amount of oil of lubricating viscosity, a large amount of (A) an overbased metal hydroxybenzoate detergent additive and (B) an overbased metal sulfonate detergent additive, and (C) 1-10, preferably 3 An oil soluble hydrocarbylphenol-aldehyde condensate additive in an amount in the range of 6% by weight;
Said additive package, wherein the ratio of (A) to (B) expressed as millimoles of soap is in the range of 90:10 to 10:90, preferably 80:20 to 20:80. A two-stroke or four-stroke marine engine lubricating oil composition,
Comprising a large amount of oil of lubricating viscosity and a small amount blended with the additive package of claim 1;
2 stroke engine compositions have a TBN of 10-120, preferably 40-100 using ASTM D2896, and 4 stroke engines compositions have a TBN of 25-60 using ASTM D2896. , The composition.   The additive package or composition of claim 1 or 2, wherein (A) is an overbased calcium salicylate detergent.   4. The additive package or composition of any one of claims 1-3, wherein (B) is an overbased calcium sulfonate detergent.   The additive package or composition of any one of claims 1 to 4, wherein (C) is a methylene bridged alkylphenol, the hydroxyl group of which is capped or uncapped.   6. A composition according to any one of claims 2 to 5, in the form of a marine diesel cylinder lubricant.   An additive (A) in the lubricant in an additive package for marine diesel lubricants, containing the additives (A) and (B) according to claim 1 in the ratio according to claim 1. ) And (B) for improving the stability of 1 to 10% by weight of additive (C) according to claim 1 or 5.   A method of lubricating a crosshead marine diesel engine, comprising the step of supplying the piston / cylinder of the engine to the piston / cylinder of the engine during operation of the engine.