Process for preparation of overbased alkaline earth metal alkyl hydroxybenzoate salts

Abstract

The present invention provides a process for preparing an overbased alkaline earth metal alkylhydroxybenzoate, the process comprising the steps of reacting an alkylphenol with an alkali metal hydroxide in the presence of a diluent oil to produce an alkali metal alkylphenate; carboxylating the alkali metal alkylphenolate with carbon dioxide; acidifying the alkali metal alkylhydroxybenzoic acid salt to produce an alkylhydroxybenzoic acid; adding methanesulfonic acid, a monohydric alcohol, water, and an alkaline earth metal base to the alkylhydroxybenzoic acid to form an alkaline earth metal alkylhydroxybenzoate and at least one alkaline earth metal sulfonate; and reacting the alkaline earth metal alkylhydroxybenzoate with at least one acidic highly alkalized substance in the presence of at least one alkaline earth metal sulfonate and a monohydric alcohol.

Description

Background Technology

[0001] Detergents are known additives used in lubricating compositions. One type of detergent is an alkaline earth metal hydroxybenzoate. There is a need in the art to provide improved methods for preparing alkaline earth metal hydroxybenzoates. Summary of the Invention

[0002] This invention relates to a method for preparing alkaline earth metal alkyl hydroxybenzoates.

[0003] The method of the present invention relates to the preparation of highly alkaline earth metal alkyl hydroxybenzoates using the following steps: (a) reacting alkylphenol with an alkali metal hydroxide in the presence of a diluent oil to produce an alkali metal alkylphenol salt; (b) carboxylating the alkali metal alkylphenol salt obtained in step (a) with carbon dioxide, such that at least 50 mol% of the alkali metal alkylphenol salt is converted to an alkali metal alkyl hydroxybenzoate; (c) acidifying the alkali metal alkyl hydroxybenzoate obtained in step (b) with an aqueous solution of a strong acid to produce alkyl hydroxybenzoic acid and an alkali metal salt of the strong acid; (d) separating the alkali metal salt of the strong acid from the alkyl hydroxybenzoic acid; (e) adding methanesulfonic acid, a monohydric alcohol, water, and an alkaline earth metal base to the alkyl hydroxybenzoic acid to form an alkaline earth metal alkyl hydroxybenzoate and at least one alkaline earth metal sulfonate; and (f) reacting the alkaline earth metal alkyl hydroxybenzoate with at least one acidic, highly alkaline substance in the presence of at least one alkaline earth metal sulfonate and a monohydric alcohol. Detailed Implementation

[0004] Before discussing the invention in detail, unless otherwise expressly stated to the contrary, the following terms will have the following meanings.

[0005] definition

[0006] The term "alkali metal" or "alkaline metal" refers to lithium, sodium, or potassium.

[0007] The term "alkaline earth metals" refers to calcium, barium, magnesium, and strontium.

[0008] The term "alkyl" refers to both straight-chain alkyl groups and branched-chain alkyl groups.

[0009] The term "alkylphenol salt" refers to the metal salt of alkylphenol.

[0010] The term "alkylphenol" means phenol having one or more alkyl substituents, wherein at least one of the alkyl substituents has a sufficient number of carbon atoms to impart oil solubility to the phenol.

[0011] The term "aryl group" refers to substituted or unsubstituted aromatic groups, such as phenyl groups, tolyl groups, xylyl groups, ethylphenyl groups, and isopropylphenyl groups.

[0012] The term "hydrocarbon group" refers to an alkyl group or an alkenyl group.

[0013] The term "alkylphenol" refers to phenol having one or more alkyl substituents; at least one of the alkyl substituents has a sufficient number of carbon atoms to impart oil solubility to the phenol.

[0014] The term "lime" refers to calcium hydroxide, also known as slaked lime or quicklime.

[0015] The term "highly basic" refers to a class of metal salts or complexes. Highly basic products are metal salts or complexes characterized by a metal content exceeding the stoichiometry of the metal and a specific acidic organic compound (e.g., a carboxylic acid) that would be present based on the metal and the specific acidic organic compound (e.g., a carboxylic acid) that reacts with the metal.

[0016] The term "phenol salt" refers to the metal salt of phenol.

[0017] The term "Total Base Number" or "TBN" refers to the equivalent milligrams of KOH required to neutralize 1 gram of the product. Therefore, a high TBN reflects a strongly basic product and thus represents a higher base reserve for neutralizing acids. The TBN of a product can be determined using ASTM standard number D2896 or an equivalent procedure.

[0018] High alkaline earth metal alkyl hydroxybenzoate

[0019] This invention provides a method for preparing highly alkaline earth metal alkyl hydroxybenzoates. Alkaline earth metal alkyl hydroxybenzoates prepared using the method of this invention will generally have the structure shown in formula (I).

[0020] Mode

[0021]

[0022] Wherein R is a straight-chain aliphatic group, a branched aliphatic group, or a mixture of straight-chain aliphatic groups and branched aliphatic groups. Preferably, R is an alkyl or alkenyl group. More preferably, R is an alkyl group. M is an alkaline earth metal selected from the group consisting of calcium, barium, magnesium, and strontium. Calcium and magnesium are preferred alkaline earth metals. More preferably, calcium. When R is a straight-chain aliphatic group, the straight-chain alkyl group typically contains 12 to 40, or 14 to 30, or 16 to 20 carbon atoms. When R is a branched aliphatic group, the branched alkyl group typically contains at least 9, or about 9 to 40, or about 9 to 24, or 10 to 18 carbon atoms. Such branched aliphatic groups are preferably derived from oligomers of propylene or butene. R may also represent a mixture of straight-chain or branched aliphatic groups. When R represents a mixture of aliphatic groups, the alkaline earth metal alkyl hydroxybenzoic acid used in this invention may contain a mixture of straight-chain groups, a mixture of branched-chain groups, or a mixture of straight-chain and branched-chain groups. Therefore, R can be a mixture of straight-chain aliphatic groups, for example, alkyl groups selected from the group consisting of C14-C16, C16-C18, C18-C20, C20-C22, C20-C24, and C20-C28 alkyl groups and mixtures thereof, and the alkyl groups are derived from normal α-olefins. In some embodiments, these mixtures contain at least 95 mol% or even 98 mol% alkyl groups and are derived from the polymerization of ethylene.

[0023] The -COOM group in formula (I) can be located in the ortho, meta, or para position relative to the hydroxyl group.

[0024] The alkaline earth metal alkyl hydroxybenzoate of the present invention can be any mixture of alkaline earth metal alkyl hydroxybenzoates having a -COOM group at the ortho, meta, or para position.

[0025] The alkaline earth metal alkyl hydroxybenzoate of the present invention is generally soluble in oil.

[0026] In one embodiment, the TBN of the highly alkaline earth metal alkyl hydroxybenzoate detergent is greater than 250, for example, about 250 to 450, or even about 300 to 400. In another embodiment, the TBN of the highly alkaline earth metal alkyl hydroxybenzoate of the present invention is about 100 to 250, or about 140 to 230.

[0027] process

[0028] The method of the present invention for preparing highly alkaline earth metal alkyl hydroxybenzoate comprises the following steps: (a) reacting alkylphenol with an alkali metal hydroxide in the presence of a diluent oil to produce an alkali metal alkylphenol salt; (b) carboxylating the alkali metal alkylphenol salt obtained in step (a) with carbon dioxide, such that at least 50 mol% of the alkali metal alkylphenol salt is converted to an alkali metal alkyl hydroxybenzoate; (c) acidifying the alkali metal alkyl hydroxybenzoate obtained in step (b) with an aqueous solution of a strong acid to produce alkyl hydroxybenzoic acid and an alkali metal salt of the strong acid; (d) separating the alkali metal salt of the strong acid from the alkyl hydroxybenzoic acid; (e) adding methanesulfonic acid, a monohydric alcohol, water, and a molar excess of an alkaline earth metal base to the alkyl hydroxybenzoic acid to form an alkaline earth metal alkyl hydroxybenzoate and at least one alkaline earth metal sulfonate; (f) reacting the alkaline earth metal alkyl hydroxybenzoate with at least one acidic, highly alkaline substance in the presence of at least one alkaline earth metal sulfonate and a monohydric alcohol. Each of these process steps will be described in more detail below.

[0029] A. Formation of alkali metal alkylphenol salts

[0030] In the first step, in the presence of a diluent oil, an alkali metal base is used to neutralize the alkylphenol to form an alkali metal alkylphenol salt. The alkylphenol used in this invention may contain up to 100% by weight of a straight-chain hydrocarbon group, up to 100% by weight of a branched-chain hydrocarbon group, or both a straight-chain hydrocarbon group and a branched-chain hydrocarbon group. In one embodiment, the straight-chain hydrocarbon group is an alkyl group, and such a straight-chain alkyl group contains about 12 to 40 carbon atoms, or about 14 to 30 carbon atoms, or even 16 to 20 carbon atoms. In one embodiment, the branched-chain hydrocarbon group is an alkyl group, and contains at least 9 carbon atoms, or about 9 to 40 carbon atoms, or about 9 to 24 carbon atoms, or even about 10 to 18 carbon atoms. In one embodiment, the alkylphenol may contain a mixture of linear alkylphenols and branched alkylphenols, for example, a mixture of up to 85% by weight of linear alkylphenols (preferably at least 35% by weight) and at least 15% by weight of branched alkylphenols. In another embodiment, the alkylphenol is 100% linear alkylphenol.

[0031] Branched alkylphenols can be obtained by reacting phenol with branched olefins (usually derived from propylene). They consist of a mixture of monosubstituted isomers, with the vast majority of substituents at the para position, a few at the ortho position, and almost none at the meta position.

[0032] Linear alkylphenols can be obtained by reacting phenol with linear olefins (usually derived from ethylene). They comprise mixtures of monosubstituted isomers in which the proportions of ortho, meta, and para linear alkyl substituents are more evenly distributed. Linear alkylphenols may contain alkyl substituents with a degree of branching, which increases the amount of para substituents and also increases their relative reactivity to alkali metal bases.

[0033] Alkali metal bases that can be used to perform this step include oxides or hydroxides of lithium, sodium, or potassium. In one embodiment, potassium hydroxide is preferred. In another embodiment, sodium hydroxide is preferred.

[0034] In this reaction step, an excess of alkali metal base is used. In this step, the ratio of alkali metal base to alkylphenol is preferably about 1.005:1 to 1.2:1, or 1.05:1 to 1.1:1, or 1.01:1 to 1.08:1.

[0035] The step of forming the alkali metal alkylphenol salt is carried out in the presence of a diluent oil. In one embodiment, the diluent oil is selected from Group II, Group III oils, or mixtures thereof. The viscosity of the diluent oil is preferably 2 cSt to 8 cSt (KV100, measured by ASTM D445-100). In one embodiment, the diluent oil accounts for 25% to 50% by weight of the total reaction mixture.

[0036] After the reaction step is completed, any water is removed by methods known to those skilled in the art (including distillation, flash evaporation, vacuum stripping). Water is removed until the mixture contains less than 0.5% by weight of water.

[0037] B. Carboxylation

[0038] The carboxylation step is carried out by bubbling carbon dioxide (CO2) into a reaction medium derived from the aforementioned neutralization step, and continues until at least 50 mol% or even at least 75 mol% or even at least 80 mol% of the alkali metal alkylphenol salt has been converted into an alkali metal alkyl hydroxybenzoate (as measured by potentiometric determination in hydroxybenzoic acid).

[0039] The diluent oil content in the mixture remains the same as in the previous step.

[0040] C. Acidification

[0041] The purpose of this step is to acidify the alkyl hydroxybenzoate diluted in oil to obtain alkyl hydroxybenzoic acid. Any acid stronger than alkyl hydroxybenzoic acid can be used. For example, hydrochloric acid, sulfuric acid, perchloric acid, or phosphoric acid can be used in this invention.

[0042] The acidification step is carried out with an acid having a pKa less than 2.5. In another embodiment, an acid is used that has an H+ equivalent excess of 1 H+ equivalent%, 5 H+ equivalent%, 10 H+ equivalent%, or 20 H+ equivalent% relative to potassium hydroxide, and the acidification is complete. In one embodiment, an acid is used that has an H+ equivalent% to 5 H+ equivalent%.

[0043] In one embodiment, sulfuric acid is used. The sulfuric acid may be diluted in water to a concentration of 35% to 99% by weight, 40% to 60% by weight, or even 45% to 55% by weight. The amount of sulfuric acid used relative to the hydroxybenzoate (salicylate) is 0.5 mol or at least 0.5 mol or even 0.5 mol to 0.6 mol of sulfuric acid per mole of hydroxybenzoate.

[0044] The acidification reaction is carried out with stirring or using any suitable mixing system at a temperature of about room temperature to 95°C, for example, 75°C to 95°C.

[0045] After the acidification reaction is complete, water is removed by distillation, vacuum stripping or flash evaporation, while the reaction product is continuously stirred.

[0046] D. Separation

[0047] The product from the acidification step is an oil phase solution containing alkyl hydroxybenzoic acid. The product is filtered to remove solid alkali metals from the oil phase, which contains alkyl hydroxybenzoic acid and any residual alkylphenols from the diluted oil.

[0048] E. High alkalinity

[0049] In this step, sulfonic acid, at least one monohydric alcohol, water, and an alkaline earth metal base are added to alkyl hydroxybenzoic acid to form alkaline earth metal alkyl hydroxybenzoate and at least one alkaline earth metal sulfonate.

[0050] The sulfonic acid may be selected from acids such as methanesulfonic acid, p-toluenesulfonic acid, and dodecylbenzenesulfonic acid, or mixtures thereof. In one embodiment, the sulfonic acid comprises or is composed of methanesulfonic acid. In one embodiment, the methanesulfonic acid is an aqueous solution containing 70% to 98% methanesulfonic acid in water. In another embodiment, the methanesulfonic acid is diluted in water to 15% methanesulfonic acid.

[0051] A usable monohydric alcohol includes methanol, ethanol, propanol, isopropanol, butanol, isobutanol, tert-butanol, pentanol, and mixtures thereof. In one embodiment, the monohydric alcohol comprises or is composed of methanol. In another embodiment, the monohydric alcohol comprises or is composed of butanol. In yet another embodiment, the monohydric alcohol is a mixture of methanol and butanol. In one embodiment, the monohydric alcohol comprises a mixture of ethanol and butanol. The methanol:butanol ratio can be from 1:3 to 3:1.

[0052] The alkaline earth metal base is selected from calcium oxide, calcium hydroxide, magnesium oxide, or magnesium hydroxide. In one embodiment, the alkaline earth metal base comprises or is composed of calcium oxide. In another embodiment, the alkaline earth metal base comprises or is composed of calcium hydroxide.

[0053] In the reaction mixture, the ratio of the monohydric alcohol to the alkaline earth metal base is 0.1:1 to 10:1, or 0.2:1 to 4:1, and the ratio of methanesulfonic acid to the alkaline earth metal base is 0.001:1 to 0.2:1, or 0.01:1 to 0.1:1.

[0054] The high alkalinization of alkaline earth metal alkyl hydroxybenzoates can be carried out by any method known to those skilled in the art.

[0055] Generally, the high alkalization reaction is carried out in a reactor containing about 10% to about 70% by weight of alkyl hydroxybenzoic acid, about 1% to 30% by weight of alkylphenol, and about 1% to 50% by weight of diluent oil.

[0056] The degree of high alkalinity can be controlled by the amount of alkaline earth metals, carbon dioxide, and reactants added to the reaction mixture, as well as the reaction conditions used during carbonation.

[0057] During the high alkalinization process, an alkaline earth metal base is added such that the ratio of alkaline earth metal base to alkyl hydroxybenzoic acid is 1:1 to 10:1 or 1:1 to 5:1 equivalents to provide highly alkaline earth metal hydroxybenzoates with a TBN of 100 to 250, or a ratio of 5:1 to 10:1 equivalents to provide highly alkaline earth metal hydroxybenzoates with a TBN greater than 250. Furthermore, the ratio of carbon dioxide to alkaline earth metal base is 0.6:1 to 1:1, for example, 0.8:1 equivalents.

[0058] In one embodiment, the method of the present invention for preparing highly alkaline earth metal alkyl hydroxybenzoates is carried out in the absence of elemental sulfur, i.e., the reactants, solvents, diluents, or other components do not introduce elemental sulfur into the reaction process. Those skilled in the art will understand that the use of methanesulfonic acid does not introduce elemental sulfur into the reaction.

[0059] Filter aid unit consumption

[0060] The filter aid unit consumption (FAUC) used in this article is based on an oil flow rate of 0.41 g / min / cm. 2 Up to 0.56 g / min / cm 2 The filter aid achieves a concentration of at least 0.44 g / min / cm. 2 The minimum weight percentage (based on the total weight of the material to be filtered) of a specific filter aid (diatomaceous earth) required for the oil flow rate is determined using oil with a viscosity of 36 to 37 cSt at 40°C.

[0061] The oil flow rate for a specific filter aid was determined by placing a 10-15 mm thick filter cake of 16 g of filter aid on a 4-inch Buchner funnel. The flow rate of oil with a viscosity of 36-37 cSt at 40°C was measured under a vacuum of 385 Torr through the filter aid material. The flow rate was measured by weighing the filtered oil collected over a predetermined time.

[0062] Using a laboratory pressurized leaf filter unit, the oil flow rate measured using the method described above was 0.41 g / min / cm. 2 Up to 0.56 g / min / cm 2 FAUC of diatomaceous earth filter aid was measured. The crude detergent product from the high-alkalinization step was preheated to 150°C and held for 10 minutes, then 8% by weight (based on the total weight of the crude detergent) of filter aid was added to the crude detergent. The mixture of crude detergent and filter aid was then filtered through a pressure leaf filter at 150°C and 5 PSIG to stabilize the filter pad. The filtered material was then preheated at 150°C for 10 minutes and then passed a second time at 35 PSIG. The detergent in the oil phase was collected in a wide-mouth bottle on a balance, allowing the flow rate to be determined in g / min. A "through" flow rate of >0.44 g / min / cm³ was recorded. 2 If the sample passes at 8%, reduce the amount of filter aid to 4% by weight for the second test. If the sample fails to pass at 8%, increase the amount of filter aid to 12% by weight for the second test. The remaining tests follow the attached workflow until the minimum percentage of filter aid required to achieve the filtration rate is determined.

[0063] Filter aid unit consumption workflow

[0064]

[0065] *Use oil with a viscosity of 36 to 37 cSt at 40°C and an oil flow rate of 0.41 g / min / cm. 2 Up to 0.56 g / min / cm 2 Diatomaceous earth filter aid.

[0066] In one embodiment of the invention, the method unexpectedly reduces the unit consumption of filter aid. For example, the method of the invention produces a product with a FAUC of 2% to 3% by weight.

[0067] Lubricating oil composition

[0068] The present invention also relates to lubricating oil compositions containing highly alkaline earth metal alkyl hydroxybenzoates prepared by the method of the present invention.

[0069] Oil with lubricating viscosity

[0070] The lubricating compositions of the present invention comprise oils having a lubricating viscosity. Such oils include natural and synthetic oils, oils derived from hydrocracking, hydrogenation, and hydrorefining, unrefined oils, refined oils, re-refined oils, or mixtures thereof. A more detailed description of unrefined, refined, and re-refined oils is provided in paragraphs

[0054] through

[0056] of International Publication WO2008 / 147704 (a similar disclosure is provided in U.S. Patent Publication 2010 / 0197536, see

[0072] through

[0073] ). More detailed descriptions of natural and synthetic lubricating oils are provided in paragraphs

[0058] through

[0059] of WO2008 / 147704 (a similar disclosure is provided in U.S. Patent Publication 2010 / 0197536, see

[0075] through

[0076] ). Synthetic oils can also be produced via the Fischer-Tropsch reaction, and are typically hydroisomerized Fischer-Tropsch hydrocarbons or waxes. In one embodiment, the oil can be prepared via a Fischer-Tropsch gas-to-liquid synthesis process and other gas-to-liquid oils.

[0071] Oils with lubricating viscosity can also be defined as specified in subsection 1.3, “Base Stock Categories,” of Appendix E – API Base Oil Interchangeability Guidelines for PassengerCar Motor Oils and Diesel Engine Oils, April 2008 edition. The API guidelines are also outlined in U.S. Patent No. 7,285,516 (see column 11, line 64 through column 12, line 10). The five base oil categories are as follows:

[0072]

[0073] The amount of oil with lubricating viscosity present in the lubricating composition is typically the balance remaining after subtracting the sum of the amounts of the compounds of the present invention and other performance additives from 100% by weight (wt%).

[0074] The lubricating composition may be in the form of a concentrate and / or a fully formulated lubricant. If the lubricating composition of the present invention (containing the additives disclosed herein) is in the form of a concentrate that can be combined with an additional oil to form all or part of a finished lubricant, the ratio of these additives to oils and / or diluents having a lubricating viscosity includes a range of 1:99 to 99:1 by weight or 80:20 to 10:90 by weight.

[0075] In one embodiment, the base oil has a kinematic viscosity at 100°C ranging from 2 mm² / s (centi Stokes - cSt) to 16 mm² / s, 3 mm² / s to 10 mm² / s, or even 4 mm² / s to 8 mm² / s.

[0076] The solubility of a base oil can be measured by its ability to act as a solvent for polar components without any added base oil. Generally, the solubility of a base oil decreases as it transitions from Group I to Group IV (PAO). That is, for a given kinematic viscosity, the solubility of base oils can be ranked as follows: Group I > Group II > Group IV. The solubility of a base oil also decreases with increasing viscosity within the base oil group; lower viscosity base oils tend to have better solubility than similar base oils with higher viscosity. The solubility of a base oil can be measured using the aniline point (ASTM D611).

[0077] In one embodiment of the invention, the base oil component of the lubricating composition comprises at least 30 wt%, at least 40 wt%, at least 50 wt%, at least 60 wt%, at least 70 wt%, or at least 80 wt% of Group I, II, or III base oils, or mixtures thereof. Furthermore, the lubricating composition comprises less than 50 wt%, less than 40 wt%, or less than 30 wt%, or less than 20 wt% of Group IV (i.e., polyalphaolefin) base oil. In another embodiment, the base oil comprises less than 10 wt% of Group IV base oil. In yet another embodiment, the lubricating composition is substantially free of (i.e., contains less than 0.5 wt% of) Group IV (polyalphaolefin) base oil.

[0078] Ester-based fluids, known as Group V oils, possess high solubility levels due to their polar nature. Adding a low concentration (typically less than 10% by weight) of ester to a lubricating composition can significantly increase the solubility of the resulting base oil mixture. Esters can be broadly classified into two categories: synthetic esters and natural esters. Ester-based fluids have kinematic viscosities at 100°C suitable for engine oil lubricants, such as between 2 cSt and 30 cSt, or 3 cSt to 20 cSt, or even 4 cSt to 12 cSt.

[0079] Synthetic esters may comprise esters of dicarboxylic acids (e.g., phthalic acid, succinic acid, alkyl succinic acid and alkenyl succinic acid, maleic acid, azelaic acid, octanoic acid, sebacic acid, fumaric acid, adipic acid, linoleic acid dimer, malonic acid, alkyl malonic acid and alkenyl malonic acid) and any of a variety of monohydric alcohols (e.g., butanol, hexanol, dodecyl alcohol, 2-ethylhexanol, ethylene glycol, diethylene glycol monoether and propylene glycol). Specific examples of these esters include dibutyl adipate, di(2-ethylhexyl) sebacic acid ester, di-n-hexyl fumarate, dioctyl sebacic acid, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, didecyl phthalate, dieicosyl sebacic acid, 2-ethylhexyl diester of linoleic acid dimer, and a complex ester formed by reacting 1 mole of sebacic acid with 2 moles of tetraethylene glycol and 2 moles of 2-ethylhexanoic acid. Other synthetic esters include those prepared from C5 to C12 monocarboxylic acids and polyols and polyol ethers (such as neopentyl glycol, trimethylolpropane, pentaerythritol, dipentaerythritol, and tripentaerythritol). Esters can also be monoesters of monocarboxylic acids and monools.

[0080] Natural (or bio-derived) esters are substances derived from renewable biological resources, organisms, or entities, as opposed to substances derived from petroleum or equivalent raw materials. Natural esters include fatty acid triglycerides, hydrolyzed or partially hydrolyzed triglycerides, or transesterified triglycerides, such as fatty acid methyl esters (or FAME). Suitable triglycerides include, but are not limited to, palm oil, soybean oil, sunflower oil, rapeseed oil, olive oil, linseed oil, and related substances. Other sources of triglycerides include, but are not limited to, algae, animal lipids, and zooplankton. A method for producing bio-lubricants from natural triglycerides is described, for example, in U.S. Patent Publication 2011 / 0009300A1.

[0081] Other additive components

[0082] The compositions of the present invention may optionally contain one or more other additional performance additives. These additional performance additives may include, but are not limited to, one or more dispersants, including borate dispersants, anti-wear additives, detergents, metal deactivators, viscosity modifiers, friction modifiers, anti-wear agents, corrosion inhibitors, dispersant viscosity modifiers, extreme pressure agents, foam inhibitors, demulsifiers, pour point depressants, sealing expanders, and any combination or mixture thereof. Typically, a fully formulated lubricant will contain one or more of these performance additives, and usually contains a set of multiple performance additives.

[0083] In one embodiment, the present invention provides a lubricating composition further comprising a detergent. In one embodiment, the detergent may be an alkali metal or alkaline earth metal sulfonate detergent, an alkali metal or alkaline earth metal salicylate detergent, an alkali metal or alkaline earth metal salicylate detergent, or an alkali metal or alkaline earth metal phenolate detergent. The detergent may be a highly alkaline detergent. Highly alkaline detergents, also known as highly alkaline or superalkaline salts, are characterized by a metal content exceeding the amount necessary for neutralization based on the stoichiometry of the metal and the specific acidic organic compound that reacts with the metal. Highly alkaline detergents are known in the art, and the lubricating compositions of the present invention may contain detergents now known to those skilled in the art or subsequently developed and understood to be suitable for use in the present invention.

[0084] In one embodiment, the detergent may comprise a highly alkaline metal sulfonate detergent. The highly alkaline metal sulfonate detergent may comprise a calcium, magnesium, sodium salt, or mixture thereof of one or more sulfonates. Other available metals may include titanium and zirconium. Highly alkaline sulfonates typically have a total base number of 250 to 600, or 300 to 500. In one embodiment, the sulfonate detergent may be primarily a linear alkylbenzene sulfonate detergent with a metal ratio of at least 8, as described in paragraphs

[0026] to

[0037] of U.S. Patent Publication 2005065045 (and granted U.S. Patent 7407919). The linear alkyl group may be attached to a benzene ring at any position along the straight chain of the alkyl group (but typically at positions 2, 3, or 4 of the straight chain, and in some cases, primarily at position 2), resulting in a linear alkylbenzene sulfonate detergent.

[0085] In one embodiment, the lubricating composition may comprise an alkali metal or alkaline earth metal salicylate detergent or a salicylate detergent, or a mixture thereof. The metal salicylate or salicylate detergent may be a highly alkaline detergent. Available salicylate and salicylate detergents may comprise calcium salts, magnesium salts, sodium salts, or mixtures thereof. Other available metals may include titanium and zirconium.

[0086] In one embodiment, the lubricating composition may contain a metal sulfur-coupled alkylphenol compound. Such compounds can be exemplified by phenol salt detergents containing alkali metals and alkaline earth metals (such as magnesium phenolate detergents, calcium phenolate detergents, and sodium phenolate detergents, and further including highly alkaline metal phenolate detergents) (all of which are known in the art).

[0087] In one embodiment, the detergent comprises or is composed of a calcium detergent. In another embodiment, the detergent may comprise a mixture of a calcium-containing detergent and a magnesium-containing detergent (such as those disclosed herein), wherein the detergent mixture provides 800 ppm to 1300 ppm of calcium and 450 ppm to 800 ppm of magnesium, and in another embodiment provides 900 ppm to 1200 ppm of calcium and 500 ppm to 750 ppm of magnesium.

[0088] According to some embodiments, the total amount of soap contributed by the detergent relative to the lubricating composition can be from about 0.08% or 1.0% by weight to less than 0.9% or 0.7% or 0.5% by weight, 0.4% or 0.3% by weight, or 0.25% by weight. The lubricating composition may be free of phenolic salt soap or substantially free of phenolic salt soap. As used herein, the term "soap" refers to the surfactant portion of a detergent, excluding metal bases such as calcium carbonate. The term soap may also refer to a detergent matrix. For example, the sulfonate detergents, soaps, or matrices described herein may be neutral salts of alkylbenzene sulfonic acids.

[0089] Metal-containing detergents can also contribute sulfated ash to the lubricating composition. The sulfated ash content can be determined using ASTM D874. In one embodiment, the lubricating composition of the present invention comprises a metal-containing detergent in an amount that delivers at least 0.4% by weight of sulfated ash to the total composition. In another embodiment, the metal-containing detergent is present in an amount that delivers at least 0.6% by weight of sulfated ash, or at least 0.75% by weight of sulfated ash, or even at least 0.9% by weight of sulfated ash to the lubricating composition.

[0090] In some embodiments, the lubricating composition of the present invention may contain an organophosphorus anti-wear agent. The organophosphorus anti-wear agent may be a metal-free organophosphorus anti-wear agent. The organophosphorus agent may contain sulfur or may be sulfur-free. Sulfur-free phosphorus-containing anti-wear agents may be phosphites, phosphonates, alkyl phosphates, amines, or ammonium phosphates, or mixtures thereof.

[0091] Phosphate esters, such as dihydro and trihydrophosphites, such as dibutyl phosphite, diheptyl phosphite, dicyclohexyl phosphite, pentylphenyl phosphite; dipentylphenyl phosphite, tridecyl phosphite, distearate phosphite, and polypropylene-substituted phenolic phosphites; metal thiocarbamates, such as zinc dioctyl dithiocarbamate and barium heptylphenol diacid; amine salts or derivatives of alkyl and dialkyl phosphates, including, for example, amine salts of the product of the reaction of dialkyl dithiophosphite with propylene oxide and subsequently with P2O5; and mixtures thereof (as described in US 3,197,405).

[0092] Aminophosphates can be the following amine salts: (i) monoalkyl phosphates, (ii) dialkyl phosphates, (iii) hydroxyl-substituted phosphate diesters, or (iv) phosphorylated hydroxyl-substituted phosphate diesters or tripesters. Amino salts of sulfur-free phosphorus-containing compounds can be salts of primary, secondary, or tertiary amines, or mixtures thereof.

[0093] Aminophosphates can be derived from monoalkyl phosphates or dialkyl phosphates (typically alkyl phosphates) or mixtures thereof. The alkyl group of a monoalkyl or dialkyl phosphate can comprise a straight-chain or branched alkyl group having 3 to 36 carbon atoms. The hydrocarbon group of a straight-chain or branched hydrocarbon phosphate can contain 4 to 30 or 8 to 20 carbon atoms. Examples of suitable hydrocarbon groups for hydrocarbon phosphates may include isopropyl, n-butyl, sec-butyl, pentyl, 4-methyl-2-pentyl (i.e., methylpentyl), n-hexyl, n-heptyl, n-octyl, isooctyl, 2-ethylhexyl, nonyl, 2-propylheptyl, decyl, dodecyl, tetradecyl, hexadecyl, octadecyl, oleyl, or combinations thereof. In one embodiment, the phosphate is a mixture of mono- and di(2-ethyl)hexyl phosphates.

[0094] Examples of suitable primary amines include ethylamine, propylamine, butylamine, 2-ethylhexylamine, octylamine, and dodecylamine, as well as aliphatic amines such as n-octylamine, n-decylamine, n-dodecylamine, n-tetradecylamine, n-hexadecylamine, n-octadecylamine, and oleylamine. Other available aliphatic amines include commercially available aliphatic amines, such as... Amines (available from Akzo Chemicals, Chicago, Illinois), such as Armeen C, Armeen O, Armeen OL, Armeen T, Armeen HT, Armeen S, and Armeen SD, where the letter designation relates to an aliphatic group (such as coconut oil, oil, tallow, or stearin).

[0095] In one embodiment, the metal-free phosphorus anti-wear agent may be present in the lubricant composition in an amount of 0.01 wt% to 5 wt%, or 0.1 wt% to 3.2 wt%, or 0.35 wt% to 1.8 wt%, or 0.5 wt% to 1.5 wt%, or 0.5 wt% to 0.9 wt%. In one embodiment, the metal-free phosphorus anti-wear agent may be present in an amount of 0.01 wt% to 0.15 wt% phosphorus, 0.01 wt% to 0.08 wt% phosphorus, or 0.025 wt% to 0.065 wt% phosphorus.

[0096] In another embodiment, the lubricating composition of the present invention is free of or substantially free of phosphorus or phosphorus-containing agents.

[0097] In one embodiment, the present invention provides a lubricating composition further comprising an ashless anti-wear agent different from the organophosphorus anti-wear agents described above. Examples of suitable anti-wear agents include hydroxy-carboxylic acid derivatives such as esters, amides, imides or amines or ammonium salts, sulfurized olefins, and thiocarbamate compounds such as thiocarbamates, thiocarbamate amides, thiocarbamate ethers, alkylene-coupled thiocarbamates, and bis(S-alkyldithiocarbamate) disulfides.

[0098] In one embodiment, the ashless anti-wear agent may comprise a compound derived from a hydroxycarboxylic acid. In one embodiment, the ashless anti-wear agent is derived from at least one of hydroxy-polycarboxylate diester, hydroxy-polycarboxylate diamide, hydroxy-polycarboxylate imide, and hydroxy-polycarboxylate ester amide. In one embodiment, the ashless anti-wear agent is derived from a hydroxy-polycarboxylate imide.

[0099] Examples of suitable hydroxycarboxylic acids include citric acid, tartaric acid, lactic acid, glycolic acid, hydroxypropionic acid, hydroxyglutaric acid, or mixtures thereof. In one embodiment, the ashless anti-wear agent is derived from tartaric acid, citric acid, hydroxysuccinic acid, dihydroxymonoacid, monohydroxydiacid, or mixtures thereof. In one embodiment, the ashless anti-wear agent comprises a compound derived from tartaric acid or citric acid. In one embodiment, the ashless anti-wear agent comprises a compound derived from tartaric acid.

[0100] U.S. Patent Application 2005 / 198894 discloses suitable hydroxycarboxylic acid compounds and methods for their preparation.

[0101] Canadian Patent 1,183,125; U.S. Patent Publication No. 2006 / 0183647 and US-2006-0079413; U.S. Patent Application No. 60 / 867,402; and British Patent 2,105743A all disclose examples of suitable tartaric acid derivatives. In one embodiment, the anti-wear agent may comprise tartrates or tartrate imides as disclosed in International Publication WO 2006 / 044411 or Canadian Patent CA 1,183,125. Tartrates or tartrate imides may contain alkyl ester groups, wherein the total number of carbon atoms on the alkyl groups is at least 8. In one embodiment, the anti-wear agent may comprise citrate.

[0102] Ash-free and phosphorus-free anti-wear agents may be present in the lubricating composition at 0.1% to 5% by weight, 0.1% to 3% by weight, or 0.2% to 3% by weight, or 0.1% to 1.5% by weight, or 0.5% to 1.1% by weight.

[0103] In one embodiment, the invention may also provide a lubricating composition further comprising a metal dialkyl dithiophosphate. Typically, the metal dialkyl dithiophosphate may be zinc dialkyl dithiophosphate (ZDDP) or a mixture thereof. Zinc dialkyl dithiophosphate is known in the art. Zinc dialkyl dithiophosphate may be present in amounts from 0% to 3% by weight, or from 0.1% to 1.5% by weight, or from 0.5% to 0.9% by weight of the lubricating composition. In another embodiment, ZDDP is present such that the total zinc contributing to the lubricant composition does not exceed 0.15% by weight of the composition; for example, zinc may be present in amounts from 0% to 0.15% by weight, or even less than 0.14% by weight, or even less than 0.11% by weight, or even less than 0.09% by weight, or even less than 0.07% by weight, or even less than 0.05% by weight, or even less than 0.03% by weight, and in another embodiment in amounts from 0.01% to 0.14% by weight. In another embodiment, the lubricating composition is substantially zinc-free.

[0104] Zinc dialkyl dithiophosphate can be derived from primary alcohols, secondary alcohols, or combinations thereof. Typically, they are derived from primary and secondary alcohols containing 3 to 12 carbon atoms, or combinations thereof. In one embodiment, the zinc dialkyl dithiophosphate comprises at least 25 mol% of secondary alkyl groups, or at least 40 mol% of secondary alkyl groups, or at least 75 mol% of secondary alkyl groups, or at least 90 mol% of secondary alkyl groups.

[0105] Polymer viscosity index improvers (also known as viscosity modifiers (VMs) or dispersant viscosity modifiers (DVMs)) can be used in the compositions disclosed herein. Dispersant viscosity modifiers can generally be understood as functionalized (i.e., derivatized) forms of polymers similar to polymer viscosity modifiers. Polymer viscosity modifiers can be olefin (co)polymers, poly(meth)acrylates (PMA), or mixtures thereof. In one embodiment, the polymer viscosity modifier is an olefin (co)polymer or a dispersant viscosity modifier derived therefrom.

[0106] The olefin polymer can be derived from isobutylene or isoprene. In one embodiment, the olefin polymer is prepared from ethylene and high-carbon olefins in the range of C3-C10 α-monoolefins; for example, the olefin polymer can be prepared from ethylene and propylene.

[0107] Available olefin polymers, particularly ethylene-α-olefin copolymers, have a number average molecular weight of 4,500 to 500,000 (e.g., 5,000 to 100,000, 7,500 to 60,000, or 8,000 to 45,000).

[0108] The formation of functionalized ethylene-α-olefin copolymers is well known in the art, for example, as described in, column 2, lines 48 through 10, lines 38 of U.S. Patent 7,790,661. Further detailed descriptions of similar functionalized ethylene-α-olefin copolymers can be found in International Publication WO2006 / 015130 or U.S. Patents 4,863,623, 6,107,257, 6,107,258, 117,825, and US 7,790,661. In one embodiment, the functionalized ethylene-α-olefin copolymer may include those described in U.S. Patent 4,863,623 (see, column 2, lines 15 through 3, lines 52) or International Publication WO2006 / 015130 (see, page 2, paragraph

[0008] and the preparation examples as described in paragraphs

[0065] through

[0073] ).

[0109] In one embodiment, the lubricating composition comprises a dispersant viscosity modifier (DVM). The DVM may comprise an olefin polymer that has been modified by the addition of a polar portion.

[0110] Olefin polymers are functionalized by modifying the polymer through the addition of polar moieties. In one available embodiment, the functionalized copolymer is a reaction product of an olefin polymer grafted with an acylating agent. In one embodiment, the acylating agent can be an olefinically unsaturated acylating agent. Available acylating agents are typically α,β-unsaturated compounds having at least one olefinic bond (before the reaction) and at least one, for example, two carboxylic acid (or anhydride) groups, or polar groups that can be converted into said carboxyl groups by oxidation or hydrolysis. The acylating agent is grafted onto the olefin polymer to obtain two carboxylic acid functional groups. Examples of available acylating agents include maleic anhydride, chloromaleic anhydride, itaconic anhydride, or their reactive equivalents, such as the corresponding dicarboxylic acids, such as maleic acid, fumaric acid, cinnamic acid, (meth)acrylic acid, esters of these compounds, and acyl chlorides of these compounds.

[0111] In one embodiment, the functionalized ethylene-α-olefin copolymer comprises an olefin copolymer grafted with acyl groups further functionalized with a polyether compound, a hydrocarbon alcohol group, an amino group, or a hydroxyl group, or a mixture thereof.

[0112] In one embodiment, the alkylamine may be selected from aromatic amines, aliphatic amines, and mixtures thereof. In one embodiment, the alkylamine component may comprise at least one aromatic amine containing at least one amino group capable of condensing with the acyl group to provide a side group and at least one additional group comprising at least one nitrogen, oxygen, or sulfur atom, wherein the aromatic amine is selected from the group consisting of: (i) nitro-substituted aniline; (ii) an amine comprising two aromatic moieties linked by a C(O)NR- group, a -C(O)O- group, an -O- group, an N=N- group, or a -SO2- group, wherein R is hydrogen or an alkyl group, and one of the aromatic moieties carries the condensable amino group; (iii) aminoquinoline; (iv) aminobenzimidazole; (v) N,N-dialkylphenylenediamine; (vi) aminodiphenylamine (also known as N-phenylphenylenediamine); (vii) cyclic-substituted benzylamine; and (viii) a methylene coupling dimer of aminodiphenylamine.

[0113] In one embodiment, the lubricating composition may comprise a poly(meth)acrylate polymer viscosity modifier. As used herein, the term "(meth)acrylate" and its synonyms refer to methacrylate or acrylate, which will be readily understood.

[0114] In one embodiment, the poly(meth)acrylate polymer is prepared from a monomer mixture comprising (meth)acrylate monomers containing alkyl groups of varying lengths. The (meth)acrylate monomers may contain alkyl groups that are either straight-chain or branched. The alkyl groups may contain 1 to 24 carbon atoms, for example, 1 to 20 carbon atoms.

[0115] In one embodiment, the poly(meth)acrylate polymer comprises a dispersant monomer; the dispersant monomer includes those monomers that are copolymerizable with (meth)acrylate monomers and contain one or more heteroatoms in addition to the carbonyl group of the (meth)acrylate. The dispersant monomer may contain nitrogen-containing groups, oxygen-containing groups, or mixtures thereof.

[0116] The dispersant monomer may be present in an amount of up to 5 mol percent of the monomer composition of the (meth)acrylate polymer. In one embodiment, the poly(meth)acrylate is present in an amount of 0 mol percent to 5 mol percent, 0.5 mol percent to 4 mol percent, or 0.8 mol percent to 3 mol percent of the polymer composition. In one embodiment, the poly(meth)acrylate is free of or substantially free of the dispersant monomer.

[0117] In one embodiment, the poly(meth)acrylate polymer (P) is a block or graded block copolymer comprising at least one polymer block (B1) that is insoluble or substantially insoluble in the base oil and a second polymer block (B2) that is soluble or substantially soluble in the base oil.

[0118] In one embodiment, the poly(meth)acrylate polymer may have a structure selected from linear, branched, hyperbranched, crosslinked, star-shaped (also referred to as “radial”), or combinations thereof. Star-shaped or radial refers to a multi-arm polymer. Such polymers include (meth)acrylate-containing polymers comprising three or more arms or branches, and in some embodiments, containing at least about 20, or at least 50, 100, 200, 350, 500, or 1000 carbon atoms. The arms are typically linked to a multivalent organic moiety that acts as a “core” or “coupling agent.” Multi-arm polymers may be referred to as radial or star-shaped polymers or even “comb” polymers, or polymers having multiple arms or branches in other ways as described herein.

[0119] Random, block, or other forms of linear poly(meth)acrylates can have a weight-average molecular weight (Mw) of 1,000 Daltons to 400,000 Daltons, 1,000 Daltons to 150,000 Daltons, or 15,000 Daltons to 100,000 Daltons. In one embodiment, the poly(meth)acrylate can be a linear block copolymer with a Mw of 5,000 Daltons to 40,000 Daltons, or 10,000 Daltons to 30,000 Daltons. Radial, crosslinked, or star copolymers can be derived from linear random or diblock copolymers having the molecular weights described above. Star polymers can have a weight-average molecular weight of 10,000 Daltons to 1,500,000 Daltons, 40,000 Daltons to 1,000,000 Daltons, or 300,000 to 850,000 Daltons.

[0120] Another class of polymer viscosity modifiers are styrene-diene (SD) copolymers, such as styrene isoprene (SI) and styrene butadiene (SBR). Styrene-diene copolymers can be linear or radial (star-shaped) and typically contain one or more different blocks of styrene attached to one or more different blocks of hydrogenated diene.

[0121] In some embodiments, the lubricating composition may contain 0.05% to 4% by weight, or 0.08% to 2% by weight, or 0.1% to 1% by weight of one or more polymeric viscosity modifiers and / or dispersants. In other embodiments, the lubricating composition may contain no or substantially no polymeric viscosity modifier.

[0122] In one embodiment, the present invention provides a lubricating composition further comprising a molybdenum compound. The molybdenum compound may be selected from the group consisting of molybdenum dialkyldithiophosphate, molybdenum dithiocarbamate, amine salts of molybdenum compounds, and mixtures thereof. The molybdenum compound may provide the lubricating composition with molybdenum at concentrations of 0 ppm to 1000 ppm, 5 ppm to 1000 ppm, 10 ppm to 750 ppm, 5 ppm to 300 ppm, or 20 ppm to 250 ppm.

[0123] In one embodiment, the present invention provides a lubricating composition further comprising a friction modifier. Examples of friction modifiers include long-chain fatty acid derivatives of amines, aliphatic esters, or epoxides; aliphatic imidazolines, condensation products of carboxylic acids and polyalkylene polyamines; amine salts of alkyl phosphates; aliphatic alkyl tartrate esters; aliphatic alkyl tartrate imides; or aliphatic alkyl tartrate amides. As used herein, the term "aliphatic" may mean having a C8-22 straight-chain alkyl group.

[0124] Friction modifiers can also include materials such as sulfurized aliphatic compounds and olefins, molybdenum dialkyl dithiophosphate, molybdenum dithiocarbamate, monoesters of sunflower oil or polyols, and aliphatic carboxylic acids.

[0125] In one embodiment, the friction modifier may be selected from the group consisting of: long-chain fatty acid derivatives of amines, long-chain fatty esters or long-chain fatty epoxides; fatty imidazolines; amine salts of alkyl phosphates; fatty alkyl tartrate esters; fatty alkyl tartrate imides; and fatty alkyl tartrate amides. The friction modifier may be present in 0.05% to 6% by weight, or 0.05% to 4% by weight, or 0.1% to 2% by weight of the lubricating composition.

[0126] In one embodiment, the friction modifier may be a long-chain fatty acid ester. In another embodiment, the long-chain fatty acid ester may be a monoester or diester or a mixture thereof, and in yet another embodiment, the long-chain fatty acid ester may be a triglyceride.

[0127] Other performance additives, such as corrosion inhibitors, include those described in paragraphs 5 through 8 of U.S. application US05 / 038319, published as WO2006 / 047486, octyloctylamide, dodecenylsuccinic acid or anhydride, and condensation products of fatty acids (such as oleic acid) with polyamines. In one embodiment, the corrosion inhibitor includes (A registered trademark of The Dow Chemical Company) Corrosion inhibitor. Corrosion inhibitors can be homopolymers or copolymers of propylene oxide. The corrosion inhibitor is described in more detail in the product brochure published by Dow Chemical Company, form number 118-01453-0702AMS. The brochure is titled "SYNALOX Lubricants, High-Performance Polyglycols for Demanding Application".

[0128] The lubricating composition may also contain a metal passivator, including derivatives of benzotriazole (typically toluenetriazole), dimercaptothiadiazole derivatives, 1,2,4-triazole, benzimidazole, 2-alkyldithiobenzimidazole, or 2-alkyldithiobenzothiazole; a foam inhibitor, including copolymers of ethyl acrylate and 2-ethylhexyl acrylate, and copolymers of ethyl acrylate, 2-ethylhexyl acrylate, and vinyl acetate; an antiemulsifier, including trialkyl phosphate, polyethylene glycol, polyethylene oxide, polypropylene oxide, and (ethylene oxide-propylene oxide) polymers; and a pour point depressant, including maleic anhydride-styrene esters, polymethacrylate, polyacrylate, or polyacrylamide.

[0129] Pour depressants that can be used in the compositions of the present invention also include polyalphaolefins, maleic anhydride-styrene esters, poly(meth)acrylates, polyacrylates, or polyacrylamide.

[0130] Embodiments of the present invention are defined in the following clauses:

[0131] Clause 1: A method for preparing highly alkaline earth metal alkyl hydroxybenzoate, the method comprising the steps of: (a) reacting an alkylphenol with an alkali metal hydroxide in the presence of a diluent oil to produce an alkali metal alkylphenol salt; (b) carboxylating the alkali metal alkylphenol salt obtained in step (a) with carbon dioxide, such that at least 50 mol% of the alkali metal alkylphenol salt is converted to an alkali metal alkyl hydroxybenzoate; (c) acidifying the alkali metal alkyl hydroxybenzoate obtained in step (b) with an aqueous solution of a strong acid to produce an alkyl hydroxybenzoic acid and an alkali metal salt of the strong acid; (d) separating the alkali metal salt of the strong acid from the alkyl hydroxybenzoic acid; (e) adding methanesulfonic acid, a monohydric alcohol, water, and an alkaline earth metal base to the alkyl hydroxybenzoic acid to form an alkaline earth metal alkyl hydroxybenzoate and at least one alkaline earth metal sulfonate; and (f) reacting the alkaline earth metal alkyl hydroxybenzoate with at least one acidic highly alkaline substance in the presence of at least one alkaline earth metal sulfonate and a monohydric alcohol.

[0132] Clause 2: The method described in Clause 1, wherein the method is carried out in the absence of elemental sulfur.

[0133] Clause 3: The method according to any of the preceding clauses, wherein the alkali metal hydroxide is selected from the group consisting of potassium hydroxide, sodium hydroxide, lithium hydroxide, or mixtures thereof.

[0134] Clause 4: The method according to any of the preceding clauses, wherein the molar ratio of alkali metal hydroxide to alkylphenol is 1.005:1 to 1.2:1 or 1.05:1 to 1.1:1 or 1.01:1 to 1.08:1.

[0135] Clause 5: The method according to any of the preceding clauses, wherein the alkali metal hydroxide comprises or is composed of potassium hydroxide.

[0136] Clause 6: The method according to any of the preceding clauses, wherein the viscosity of the diluent oil is 2 cSt to 8 cSt (KV100, measured by ASTM D445-100).

[0137] Clause 7: The method according to any of the preceding clauses, wherein at least 50 mol%, or at least 75 mol%, or at least 80 mol% of the alkali metal phenol salt is converted into an alkali metal alkyl hydroxybenzoate.

[0138] Clause 8: The method according to any of the preceding clauses, wherein the strong acid comprises or is composed of a strong acid with a pKa less than 2.5.

[0139] Clause 9: The method according to any of the preceding clauses, wherein the strong acid is selected from the group consisting of sulfuric acid, hydrochloric acid, perchloric acid, phosphoric acid, or mixtures thereof.

[0140] Clause 10: The method according to any of the preceding clauses, wherein the strong acid is sulfuric acid diluted in water to a concentration of 35% to 99% by weight, or 40% to 60% by weight, or 45% to 55% by weight.

[0141] Clause 11: The method according to any of the preceding clauses, wherein the monohydric alcohol comprises a monohydric alcohol having 1 to 5 carbon atoms.

[0142] Clause 12: The method according to any of the preceding clauses, wherein the monohydric alcohol is selected from the group consisting of: butanol, methanol, ethanol, propanol, isopropanol, isobutanol, tert-butanol, pentanol, or mixtures thereof.

[0143] Clause 13: The method according to any of the preceding clauses, wherein the monohydric alcohol comprises a mixture of butanol and methanol.

[0144] Clause 14: The method according to Clause 13, wherein the ratio of methanol to butanol is 1:3 to 3:1.

[0145] Clause 15: The method according to any of the preceding clauses, wherein the alkaline earth metal base is selected from calcium oxide, calcium hydroxide, or mixtures thereof.

[0146] Clause 16: The method according to any of the preceding clauses, wherein the alkaline earth metal base is calcium hydroxide.

[0147] Clause 17: The method according to any of the preceding clauses, wherein the ratio of the monohydric alcohol to the alkaline earth metal base is 0.1:1 to 10:1 or 0.2:1 to 4:1.

[0148] Clause 18: The method according to any of the preceding clauses, wherein the ratio of methanesulfonic acid to alkaline earth metal base is 0.001:1 to 0.2:1 or 0.01:1 to 0.1:1.

[0149] Clause 19: The method according to any of the preceding clauses, wherein the ratio of alkaline earth metal base to alkyl hydroxybenzoic acid is 1:1 to 10:1 equivalent or 1:1 to 5:1 equivalent, to provide a highly alkaline earth metal hydroxybenzoate with a TBN of 100 to 250.

[0150] Clause 20: The method according to any of the preceding clauses, wherein the ratio of alkaline earth metal base to alkyl hydroxybenzoic acid is 5:1 to 10:1, to provide a highly alkaline earth metal hydroxybenzoate with a TBN greater than 250.

[0151] Clause 21: The method according to any of the preceding clauses, wherein the acidic high-alkalinity substance comprises or is composed of carbon dioxide.

[0152] Clause 22: The method according to any of the preceding clauses, wherein the ratio of alkaline earth metal alkali to carbon dioxide is 0.6:1 to 1:1 or 0.8:1 to 1:1 equivalent.

[0153] Clause 23: The method according to any of the preceding clauses, wherein the highly alkaline alkaline earth metal alkyl hydroxybenzoate has an oil-free TBN of 70 to 600, or 100 to 550, or 150 to 450, or 200 to 350.

[0154] Clause 24: The method according to any of the preceding clauses, wherein the alkylphenol contains a straight-chain alkyl group, a branched-chain alkyl group, or a mixture thereof.

[0155] Clause 25: The method according to Clause 24, wherein the alkylphenol contains a straight-chain alkyl group having 12 to 40 carbon atoms, or 14 to 30 carbon atoms, or 16 to 20 carbon atoms.

[0156] Clause 26: The method according to Clause 25, wherein the straight-chain alkyl group is derived from the polymerization of ethylene.

[0157] Clause 27: The method according to any one of Clauses 1 to 24, wherein the alkylphenol contains a branched alkyl group having at least 9, or 9 to 40, or 9 to 24 carbon atoms.

[0158] Clause 28: The method according to any one of Clauses 1 to 24, wherein the alkylphenol contains 100% linear alkylphenol.

[0159] Clause 29: A highly alkaline alkaline earth metal alkyl hydroxybenzoate detergent prepared by means of the method according to any of the preceding clauses.

[0160] Clause 30: A lubricating oil composition comprising an alkaline earth metal alkyl hydroxybenzoate detergent according to Clause 29.

[0161] Clause 31: A method of lubricating an engine, the method comprising supplying the engine with a lubricating oil composition according to Clause 30.

[0162] Clause 32: The use of the method according to any one of Clauses 1 to 28 to reduce the unit consumption of filter aid in the manufacture of alkaline earth metal alkyl hydroxybenzoates.

[0163] The following examples provide an illustration of the invention. These examples are non-exhaustive and are not intended to limit the scope of the invention.

[0164] Example

[0165] In this embodiment, the following testing method is used:

[0166] • The oil viscosity is KV100 as measured according to ASTM D445-100.

[0167] • TBN (non-oil-free) is measured according to ASTM D2896A.

[0168] • A laboratory pressurized leaf filter unit was used, and the oil flow rate, measured using the method described above, was 0.41 g / min / cm. 2 Up to 0.56 g / min / cm 2 The diatomaceous earth filter aid unit consumption (FAUC) was measured. The crude detergent product from the high-alkalization step was preheated to 150°C and held for 10 minutes, then 8% by weight (based on the total weight of the crude detergent) of the filter aid was added to the crude detergent. The mixture of crude detergent and filter aid was then filtered through a pressure leaf filter at 150°C and 5 PSIG to stabilize the filter pad. The filtered material was then preheated at 150°C for 10 minutes and then passed a second time at 35 PSIG. The detergent in the oil phase was collected in a wide-mouth bottle on a balance.

[0169] • The crude precipitate was measured by placing a 25 mL sample into a 100 mL graduated cylinder containing 75 mL heptane. The crude precipitate was thoroughly mixed and centrifuged at 2,000 rpm for 20 minutes. Crude precipitate % (by volume) = test tube volume × 4.

[0170] • Turbidity was measured using a Monitek 151 turbidity meter by taking 20% ​​by volume of the filtered sample and mixing it with 80% by volume of oil. Turbidity was reported in 22 Jackson Turbidity Units (JTU).

[0171] Example X

[0172] 1595 kg of alkylphenol (a mixture of C14, 16, and 18 saturated alkyl groups) was mixed with 684 kg of 4 cSt type II oil. 562 kg of KOH alkaline solution (45% aqueous solution) was added at a rate maintaining a maximum batch temperature of 90 °C. After the addition of the alkaline solution, the mixture was heated to 150 °C to produce potassium alkylphenolate. Water was removed by distillation. The temperature was then adjusted to 125 °C. 311 kg of CO2 was uniformly added to the dehydrated mixture over 12 hours to produce potassium alkylhydroxybenzoate. 442 kg of 4 cSt oil and 31 kg of water were added. The TBN (non-oil-free) of the product from this step was determined to be 82.3 mg KOH / g. The conversion of potassium alkylphenolate to potassium alkylhydroxybenzoate was determined by NMR to be 83.7 mol%.

[0173] Example Y

[0174] The product (499 kg) of Example X was treated by adding 74.6 kg of an aqueous sulfuric acid solution (50 wt%) dropwise over 3 hours at 70°C. After the acid addition was complete, the reaction mixture was stirred at 85°C for another 2 hours. The mixture was then heated until all water was removed. The resulting slurry was then hot-filtered on a filter cloth to remove potassium sulfate, yielding a brown oil (a mixture of alkylhydroxybenzoic acid, alkylphenol, and oil). By mass balance calculation, the oil accounted for 39 wt% of the total product of this step.

[0175] Example 1

[0176] The product of Example Y (2000 g) was mixed with 250 g methanol and 250 g n-butanol, followed by the addition of 353 g quicklime to prepare a slurry. The slurry was mixed at 40°C for 30 minutes. 70 g water was added. The reaction mixture was then heated to 60°C and maintained at 60°C for 1 hour. CO2 was added at a rate of 1.6 g / min over 90 minutes. The reaction mixture was then heated to 150°C at 40 mmHg and maintained for 30 minutes to remove water, methanol, and n-butanol. 90 g oil was added to adjust the oil content to 35% by weight. The crude precipitate was 2.8% by volume. The FAUC was 8% by weight. The turbidity was 22 JTU. The TBN of the filtered detergent product was 215 mg KOH / g. The calculated oil-free TBN was 330 mg KOH / g. The filtered product (alkyl hydroxybenzoate, calcium carbonate, oil) was further diluted with oil (approximately 560g) to achieve a final TBN of 170 mg KOH / g (not oil-free).

[0177] Example 2

[0178] The product of Example Y (2000 g) was mixed with 250 g methanol, 250 g n-butanol, and 18.3 g methanesulfonic acid (70 wt% water), followed by the addition of 353 g quicklime. The slurry was mixed at 40°C for 30 minutes. 70 g water was added. The reaction mixture was then heated to 60°C and maintained at 60°C for 1 hour. CO2 was added at a rate of 1.6 g / min over 90 minutes. The reaction mixture was then heated at 40 mmHg to remove all water, methanol, and n-butanol. Finally, 90 g oil was added to adjust the oil content to 35 wt%. The crude precipitate was 0.05 vol%. The FAUC was 2 wt%. The turbidity was 38 JTU. The TBN of the filtered detergent product was 211 mg KOH / g. The calculated oil-free TBN was 325 mg KOH / g. The filtered product was further diluted with oil (approximately 560 g) to obtain a final TBN of 170 mg KOH / g.

[0179] Example 3

[0180] The product of Example Y (2000 g) was mixed with 250 g methanol and 250 g n-butanol. 353 g slaked lime was added. The slurry was mixed at 40°C for 30 minutes. 70 g water was added. The mixture was then heated to 60°C and maintained at 60°C for 1 hour. CO2 was added at a rate of 1.6 g / min over 90 minutes. 173 g slaked lime was added under N2 and mixed for 10 minutes. CO2 was added at 1.6 g / min over 1 hour. Another 173 g slaked lime was added under N2 and mixed for 10 minutes. Additional CO2 was added at a rate of 1.6 g / min for 1 hour. The reaction mixture was heated to 150°C at 40 mmHg to remove all water, methanol, and n-butanol. 90 g oil was added to adjust the oil volume to 35% by weight. The crude precipitate was 8% by volume. The TBN of the filtered detergent product was 341 mg KOH / g. The calculated oil-free TBN is 525 mg KOH / g. The FAUC is 8% by weight. The turbidity is 11.7 JTU.

[0181] Example 4

[0182] The product of Example Y (2000 g) was mixed with 250 g methanol, 250 g n-butanol, and 21 g methanesulfonic acid (70% aqueous solution). 353 g of slaked lime was added. The slurry was mixed at 40°C for 30 minutes. 70 g of water was added. The reaction mixture was then heated to 60°C and maintained at 60°C for 1 hour. CO2 was added at a rate of 1.6 g / min over 90 minutes. 173 g of slaked lime was added under N2 and mixed for 10 minutes. Additional CO2 was added at 1.6 g / min over 1 hour. An additional 173 g of slaked lime was then added under N2 and mixed for 10 minutes. CO2 was added at 1.6 g / min for 1 hour. The reaction mixture was heated to 150°C at 40 mmHg to remove all water, methanol, and n-butanol. The crude precipitate was 1.6% by volume. 90 g of oil was added to adjust the oil content to 35% by weight. The TBN of the filtered detergent product was 334 mg KOH / g. The calculated TBN for oil-free products was 514 mg KOH / g. The FAUC was 3% by weight. The turbidity was 32 JTU.

[0183] Each detergent example described above was evaluated, and the results are summarized in Table 1.

[0184] Table 1

[0185] Filter aid unit consumption

[0186]

[0187]

[0188] 1 The diatomaceous earth filter aid with an oil flow rate of 37 ml / min to 51 ml / min determined by the method described in this article.

[0189] 2 TBN / weight fraction of non-oil components.

[0190] While the invention has been explained with respect to its preferred embodiments, it should be understood that various modifications will become apparent to those skilled in the art upon reading this specification. Therefore, it should be understood that the invention disclosed herein is intended to cover such modifications that fall within the scope of the appended claims.

Claims

1. A method for preparing highly alkaline earth metal alkyl hydroxybenzoate, the method comprising the following steps: (a) In the presence of a diluent oil, react an alkylphenol with an alkali metal hydroxide to produce an alkali metal alkylphenol salt; (b) Carboxylating the alkali metal alkylphenol salt obtained in step (a) with carbon dioxide, such that at least 50 mol% of the alkali metal alkylphenol salt is converted into an alkali metal alkyl hydroxybenzoate; (c) Acidify the alkali metal alkyl hydroxybenzoate obtained in step (b) with an aqueous solution of a strong acid to produce alkyl hydroxybenzoic acid and an alkali metal salt of the strong acid; (d) Separating the alkali metal salt of the strong acid from the alkyl hydroxybenzoic acid; (e) Adding methanesulfonic acid, a monohydric alcohol, water, and an alkaline earth metal base to the alkyl hydroxybenzoic acid to form an alkaline earth metal alkyl hydroxybenzoate and at least one alkaline earth metal sulfonate; and (f) In the presence of the at least one alkaline earth metal sulfonate and the monohydric alcohol, the alkaline earth metal alkyl hydroxybenzoate is reacted with at least one acidic, highly alkaline substance.

2. The method according to claim 1, wherein the method is carried out in the absence of elemental sulfur.

3. The method according to claim 1 or 2, wherein the alkali metal hydroxide is selected from the group consisting of potassium hydroxide, sodium hydroxide, lithium hydroxide, or mixtures thereof.

4. The method according to any of the preceding claims, wherein the viscosity of the diluent oil is 2 cSt to 8 cSt (KV100, measured by ASTM D445-100).

5. The method according to any of the preceding claims, wherein the strong acid comprises or is composed of a strong acid with a pKa less than 2.

5.

6. The method according to any of the preceding claims, wherein the strong acid is selected from the group consisting of sulfuric acid, hydrochloric acid, perchloric acid, phosphoric acid, or mixtures thereof.

7. The method according to any of the preceding claims, wherein the monohydric alcohol comprises a monohydric alcohol having 1 to 5 carbon atoms.

8. The method according to any of the preceding claims, wherein the monohydric alcohol is selected from the group consisting of: butanol, methanol, ethanol, propanol, isopropanol, isobutanol, tert-butanol, pentanol, or mixtures thereof.

9. The method according to any of the preceding claims, wherein the monohydric alcohol comprises a mixture of butanol and methanol.

10. The method according to any of the preceding claims, wherein the alkaline earth metal base is selected from calcium oxide, calcium hydroxide, or mixtures thereof.

11. The method according to any of the preceding claims, wherein the alkaline earth metal base is calcium hydroxide.

12. The method according to any of the preceding claims, wherein the acidic high-alkalinity substance comprises or is composed of carbon dioxide.

13. The method according to any of the preceding claims, wherein the highly alkaline alkaline earth metal alkyl hydroxybenzoate has an oil-free TBN greater than 250.

14. The method according to any of the preceding claims, wherein the highly alkaline alkaline earth metal alkyl hydroxybenzoate has an oil-free TBN of 70 to 600, 100 to 550, 150 to 450, or 200 to 350.

15. The method according to any of the preceding claims, wherein the alkylphenol contains a straight-chain alkyl group, a branched-chain alkyl group, or a mixture thereof.

16. The method of claim 15, wherein the alkylphenol contains a straight-chain alkyl group having 12 to 40 carbon atoms, 14 to 30 carbon atoms, or 16 to 20 carbon atoms.

17. The method of claim 16, wherein the straight-chain alkyl group is derived from the polymerization of ethylene.

18. The method according to any one of claims 1 to 15, wherein the alkylphenol contains a branched alkyl group having at least 9 or 9 to 40 or 9 to 24 carbon atoms.

19. A highly alkaline alkaline earth metal alkyl hydroxybenzoate prepared by the method according to any of the preceding claims.

20. A lubricating oil composition comprising an alkaline earth metal alkyl hydroxybenzoate according to claim 19.

21. A method of lubricating an engine, the method comprising supplying the engine with the lubricating oil composition according to claim 20.

22. Use of the method according to any one of claims 1 to 18, to reduce the unit consumption of filter aid in the manufacture of alkaline earth metal alkyl hydroxybenzoates.

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