Aftertreatment system compatible engine oil formulation

Abstract

This disclosure describes a method for reducing catalyst poisoning in a diesel engine equipped with an aftertreatment system including a selective catalytic reduction device. The method includes lubricating the engine with a lubricating oil composition comprising a major amount of oil of lubricating viscosity and a Ca or Mg salicylate detergent, the lubricating oil composition lacking a Ca sulfonate surfactant.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of priority to U.S. Provisional Application No. 63 / 451,669, filed March 13, 2023, the disclosure of which is incorporated herein by reference.

[0002] This disclosure relates to engine oil formulations, and more particularly, to engine oil formulations designed to reduce emissions from internal combustion engines. [Background technology]

[0003] Carbon monoxide (CO) and nitrogen oxides (NO) from compression ignition internal combustion engines x Efforts are underway to reduce emissions such as diesel particulate filters (DPFs). An aftertreatment system is a method or device intended to reduce harmful exhaust emissions from an internal combustion engine. Some aftertreatment systems (ATSs) may employ a diesel particulate filter (DPF) to capture exhaust particles.

[0004] Another ATS approach (which may be used in combination with a DPF) is selective catalytic reduction (SCR). SCR reduces nitrogen oxides (NO) emitted from the exhaust pipe. x ) is catalytically converted to diatomic nitrogen (N2) and water. A potential drawback of SCR is its susceptibility to blockage and poisoning by soot and ash. In particular, metals from engine oil can poison the catalysts used in selective catalytic reduction. Summary of the Invention

[0005] In one aspect, there is provided a method for reducing catalyst poisoning in a diesel engine aftertreatment system equipped with a selective catalytic reduction device, comprising lubricating the engine with a lubricating oil composition comprising a major amount of oil of lubricating viscosity and a Ca or Mg salicylate-based detergent, wherein the lubricating oil composition does not contain a Ca sulfonate-based detergent.

[0006] In yet another aspect, there is provided a use of a lubricating oil composition to reduce catalyst poisoning in a diesel engine aftertreatment system equipped with a selective catalytic reduction device, the lubricating oil composition comprising a major amount of oil of lubricating viscosity and a Ca or Mg salicylate-based detergent, and the lubricating oil composition does not contain a sulfonate-based detergent. DETAILED DESCRIPTION OF THE INVENTION

[0007] Where combinations, subsets, groups, etc. of elements (e.g., combinations of components in a composition or combinations of steps in a method) are disclosed, it is understood that each of the various individual and collective combinations, and permutations of those elements is specifically contemplated and described herein, even if specific reference to each is not explicitly disclosed.

[0008] Modern engines often feature aftertreatment systems that aim to reduce harmful exhaust emissions from internal combustion engines. Aftertreatment systems use a catalyst to remove nitrogen oxides (NO x () into diatomic nitrogen (N2) and water (HO). This reduction chemical reaction occurs as the exhaust gas passes through a catalyst chamber. Just before entering the chamber, a reducing agent is injected and mixed with the exhaust gas. The reducing agent (usually ammonia) or its precursor (e.g., aqueous ammonia, urea) is usually supplied by diesel exhaust fluid (DEF). Catalysts include oxides of base metals (such as molybdenum or tungsten), zeolites, metals, or activated carbon.

[0009] This disclosure relates to lubricating oil compositions formulated to enhance or improve the performance of aftertreatment systems, particularly aftertreatment systems equipped with selective catalytic reduction systems. Metals from commonly used lubricating oil additives, such as detergents (e.g., salicylates, sulfonates, phenates) or antiwear agents (e.g., zinc dithiophosphates), are considered catalyst-poisoning compounds, making the specific formulation of these lubricating oil compositions important.

[0010] An advantage of the lubricating oil compositions of the present disclosure is that they reduce harmful emissions by reducing poisoning of catalysts used to convert harmful emissions to more harmless compounds. In another aspect, the lubricating oil compositions improve the performance of selective catalytic reduction systems. Other advantages will become apparent from the disclosure herein.

[0011] The present disclosure provides a method for reducing catalyst poisoning in a diesel engine equipped with an aftertreatment system including a selective catalytic reduction system. In some embodiments, the present disclosure provides a method for improving the performance of a diesel engine equipped with an aftertreatment system including a selective catalytic reduction system. In some embodiments, the present disclosure provides the use of a lubricating oil composition for a diesel engine equipped with an aftertreatment system including a selective catalytic reduction system.

[0012] The disclosed method includes lubricating an engine with a lubricating oil composition comprising a major amount of oil of lubricating viscosity and a detergent system including a Ca or Mg salicylate-based detergent. The lubricating oil composition is generally substantially free of calcium sulfonate due to the unexpected discovery that calcium sulfonate can cause relatively high emissions. As a result, the lubricating oil composition is calcium sulfonate-free. In some embodiments, the lubricating oil composition contains no more than about 50 ppm of Ca derived from calcium sulfonate.

[0013] Detergent-based The lubricating oil compositions of the present disclosure include a detergent system comprising one or more salicylate-based detergents. In some embodiments, the lubricating oil compositions including the detergent system unexpectedly improve aftertreatment system (ATS) conversion or NOx emissions. x Improves conversion efficiency. Detergents compatible with this disclosure include Ca or Mg salicylate-based detergents. Incompatible detergents include sulfonate-based detergents. Optional detergents include phenate-based detergents.

[0014] Salicylate-based cleansers Salicylate detergents may be prepared by reacting a basic metal compound with at least one carboxylic acid and removing water from the reaction product.

[0015] Useful salicylates include hydrocarbyl-substituted salicylic acids, such as long-chain alkyl salicylates. The term "hydrocarbyl" refers to a chemical group or moiety derived from a hydrocarbon, including saturated and unsaturated hydrocarbons. Examples of hydrocarbyl groups include alkenyl, alkyl, polyalkenyl, polyalkyl, phenyl, and the like. Hydrocarbyl-substituted salicylic acids can be prepared from phenols by the Kolbe reaction (see U.S. Pat. No. 3,595,791). Metal salts of hydrocarbyl-substituted salicylic acids can be prepared by metathesis of the metal salt in a polar solvent (such as water or alcohol).

[0016] Typical detergents are anionic, with a long-chain hydrophobic portion and a smaller, anionic or oleophobic hydrophilic portion. The anionic portion of salicylate detergents comes from the carboxylic acid. The counterion is calcium or magnesium.

[0017] Salts containing stoichiometric amounts of metals are described as neutral salts and have a total base number (TBN) of 0 to 80 mg KOH / g as measured by ASTM D-2896 method.

[0018] Many detergents are overbased, containing a large amount of metal base, achieved by reacting an excess of a metal compound (e.g., a metal hydroxide or oxide) with an acid gas (e.g., carbon dioxide) enriched.

[0019] Useful detergents can be neutral, lightly overbased, or highly overbased.

[0020] In some embodiments, at least some of the detergents used in the detergent system may be overbased. Overbased detergents help neutralize acidic impurities produced during the combustion process and trapped in the oil. The degree of overbasing generally depends on the ratio of metal ions to the anionic portion of the detergent on an equivalents basis.

[0021] Overbased detergents typically have a TBN of 10 mg KOH / g or greater, as measured by ASTM D-2896, for example, 15 mg KOH / g or greater, 25 mg KOH / g or greater, 50 mg KOH / g or greater, 75 mg KOH / g or greater, 100 mg KOH / g or greater, 125 mg KOH / g or greater, 150 mg KOH / g or greater, 175 mg KOH / g or greater, 200 mg KOH / g or greater, 225 mg KOH / g or greater, 250 mg KOH / g or greater, 275 mg KOH / g or greater, 300 mg KOH / g or greater, 325 mg KOH / g or greater, 350 mg KOH / g or greater, 375 mg KOH / g or greater, 400 mg KOH / g or greater, 425 mg KOH / g or greater, 450 mg KOH / g or greater, 475 mg KOH / g or greater, 500 mg KOH / g or greater, 525 mg KOH / g or greater KOH / g or greater, 550 mg KOH / g or greater, 575 mg KOH / g or greater, 600 mg KOH / g or greater, and TBN of 650 mg KOH / g or greater.

[0022] In some embodiments, the overbased detergent has a TBN of 10 to 650 mg KOH / g, as measured by ASTM D-2896, e.g., 10 to 600 mg KOH / g, 10 to 550 mg KOH / g, 10 to 500 mg KOH / g, 10 to 450 mg KOH / g, 10 to 400 mg KOH / g, 10 to 350 mg KOH / g, 10 to 300 mg KOH / g, 10 to 250 mg KOH / g, 10 to 200 mg KOH / g, 10 to 150 mg KOH / g, 10 to 100 mg KOH / g, 10 to 50 mg KOH / g, 50 to 650 mg KOH / g, 50 to 600 mg KOH / g, 50 to 550 mg KOH / g, 50 to 500 mg KOH / g, 50 to 450 mg KOH / g, 50~400mg KOH / g, 50~350mg KOH / g, 50~300mg KOH / g, 50~250mg KOH / g, 50~200mg KOH / g, 50~150mg KOH / g, 50~100mg KOH / g, 100~650mg KOH / g, 100~600mg KOH / g, 100~550mg KOH / g, 100~500mg KOH / g, 100~450mg KOH / g, 100~400mg KOH / g, 100~350mg KOH / g, 100~300mg KOH / g, 100~250mg KOH / g, 100~200mg KOH / g, 100~150mg KOH / g, 150~650mg KOH / g, 150~600mg KOH / g, 150~550mg KOH / g, 150~500mg KOH / g, 150~450mg KOH / g, 150~400mg KOH / g, 150~350mg KOH / g, 150~300mg KOH / g, 150~250mg KOH / g, 150~200mg KOH / g, 200~650mg KOH / g, 200~600mg KOH / g, 200~550mg KOH / g, 200~500mg KOH / g, 200~450mg KOH / g, 200~400mg KOH / g, 200~350mg KOH / g, 200~300mg KOH / g, 200~250mg KOH / g, 250~650mg KOH / g, 250~600mg KOH / g, 250~550mg KOH / g, 250~500mg KOH / g, 250~450mg KOH / g, 250~400mgKOH / g, 250~350mg KOH / g, 250~300mg KOH / g, 300~650mg KOH / g, 300~600mg KOH / g, 300~550mg KOH / g, 300~500mg KOH / g, 300~450mg KOH / g, 300~400mg KOH / g, 300~350mg KOH / g, 350~650mg KOH / g, 350~600mg KOH / g, 350~550mg KOH / g, 350~500mg KOH / g, 350~450mg KOH / g, 350~400mg KOH / g, 400~650mg KOH / g, 400~600mg KOH / g, 400~550mg KOH / g, 400-500mg KOH / g, 400-450mg KOH / g, 450-650mg KOH / g, 450-600mg KOH / g, 450-550mg KOH / g, 450-500mg KOH / g, 500-650mg KOH / g, 500-600mg KOH / g, 500-550mg KOH / g, 550-650mg KOH / g, 550-600mg KOH / g, or 600-650mg KOH / g.

[0023] In some embodiments, the overbased detergent has a TBN of 10 to 150 mg KOH / g, e.g., 10 to 140 mg KOH / g, 10 to 130 mg KOH / g, 10 to 120 mg KOH / g, 10 to 110 mg KOH / g, 10 to 100 mg KOH / g, 10 to 90 mg KOH / g, 10 to 80 mg KOH / g, 10 to 70 mg KOH / g, 10 to 60 mg KOH / g, 10 to 50 mg KOH / g, 10 to 40 mg KOH / g, 10 to 30 mg KOH / g, 10 to 20 mg KOH / g, 20 to 150 mg KOH / g, 20 to 140 mg KOH / g, 20 to 130 mg KOH / g, 20 to 120 mg KOH / g, 20 to 110 mg KOH / g, 20 to 100 mg KOH / g, 20~90mg KOH / g, 20~80mg KOH / g, 20~70mg KOH / g, 20~60mg KOH / g, 20~50mg KOH / g, 20~40mg KOH / g, 20~30mg KOH / g, 30~150mg KOH / g, 30~140mg KOH / g, 30~130mg KOH / g, 30~120mg KOH / g, 30~110mg KOH / g, 30~100mg KOH / g, 30~90mg KOH / g, 30~80mg KOH / g, 30~70mg KOH / g, 30~60mg KOH / g, 30~50mg KOH / g, 30~40mg KOH / g, 40~150mg KOH / g, 40~140mg KOH / g, 40~130mg KOH / g, 40~120mg KOH / g, 40~110mg KOH / g, 40~100mg KOH / g, 40~90mg KOH / g, 40~80mg KOH / g, 40~70mg KOH / g, 40~60mg KOH / g, 40~50mg KOH / g, 50~150mg KOH / g, 50~140mg KOH / g, 50~130mg KOH / g, 50~120mg KOH / g, 50~110mg KOH / g, 50~100mg KOH / g, 50~90mg KOH / g, 50~80mg KOH / g, 50~70mg KOH / g, 50~60mg KOH / g, 60~150mg KOH / g, 60~140mg KOH / g, 60~130mg KOH / g, 60~120mg KOH / g, 60~110mg KOH / g, 60~100mg KOH / g, 60~90mgKOH / g, 60~80mg KOH / g, 60~70mg KOH / g, 80~150mg KOH / g, 80~140mg KOH / g, 80~130mg KOH / g, 80~120mg KOH / g, 80~110mg KOH / g, 80~100mg KOH / g, 80~90mg KOH / g, 90~150mg KOH / g, 90~140mg KOH / g, 90~130mg KOH / g, 90~120mg KOH / g, 90~110mg KOH / g, 90~100mg KOH / g, 100~150mg KOH / g, 100~140mg KOH / g, 100~130mg KOH / g, 100~120mg KOH / g, 100~110mg KOH / g, 110-150mg KOH / g, 110-140mg KOH / g, 110-130mg KOH / g, 110-120mg KOH / g, 120-150mg KOH / g, 120-140mg KOH / g, 120-130mg KOH / g, 130-150mg KOH / g, 130-140mg KOH / g, or 140-150mg KOH / g.

[0024] The salicylate may be a calcium or magnesium containing salicylate, hi some embodiments, the detergent system comprises a mixture of Ca and Mg salicylates.

[0025] Calcium salicylate may be contained in the lubricating oil composition in an amount that supplies about 500 to about 5000 ppm of calcium, for example, about 500 to about 4500 ppm, 500 to 4000 ppm, 500 to 3500 ppm, 500 to 3000 ppm, 500 to 2500 ppm, 500 to 2000 ppm, 500 to 1500 ppm, 500 to 1000 ppm, 1000 to 5000 ppm, 1000 to 4500 ppm, 1000 to 4000 ppm, 1000 to 3500 ppm, 1000 to 3000 ppm, 1000 to 2500 ppm, 1000 to 2000 ppm, 1000 to 1500 ppm, 1500 to 5000 ppm, 1 500~4500ppm, 1500~4000ppm, 1500~3500ppm, 1500~3000ppm, 1500~2500ppm, 1500~2 000ppm, 2000~5000ppm, 2500~4500ppm, 2500~4000ppm, 2500~3500ppm, 2500~3000ppm , 3000 to 5000 ppm, 3000 to 4500 ppm, 3000 to 4000 ppm, 3000 to 3500 ppm, 3500 to 5000 ppm, 3500 to 4500 ppm, 3500 to 4000 ppm, 4000 to 5000 ppm, 4000 to 4500 ppm, or 4500 to 5000 ppm.

[0026] Magnesium salicylate may be contained in the lubricating oil composition in an amount that supplies about 500 to about 5000 ppm of magnesium, for example, about 500 to about 4500 ppm, 500 to 4000 ppm, 500 to 3500 ppm, 500 to 3000 ppm, 500 to 2500 ppm, 500 to 2000 ppm, 500 to 1500 ppm, 500 to 1000 ppm, 1000 to 5000 ppm, 1000 to 4500 ppm, 1000 to 4000 ppm, 1000 to 3500 ppm, 1000 to 3000 ppm, 1000 to 2500 ppm, 1000 to 2000 ppm, 1000 to 1500 ppm, 1500 to 5000 ppm, 1500~4500ppm, 1500~4000ppm, 1500~3500ppm, 1500~3000ppm, 1500~2500ppm, 1500~ 2000ppm, 2000~5000ppm, 2500~4500ppm, 2500~4000ppm, 2500~3500ppm, 2500~3000ppm m, 3000 to 5000 ppm, 3000 to 4500 ppm, 3000 to 4000 ppm, 3000 to 3500 ppm, 3500 to 5000 ppm, 3500 to 4500 ppm, 3500 to 4000 ppm, 4000 to 5000 ppm, 4000 to 4500 ppm, or 4500 to 5000 ppm.

[0027] In some embodiments, the total amount of calcium salicylate and magnesium salicylate is adjusted to a range of about 500 to about 5000 ppm, e.g., about 500 to about 4500 ppm, 500 to 4000 ppm, 500 to 3500 ppm, 500 to 3000 ppm, 500 to 2500 ppm, 500 to 2000 ppm, 500 to 1500 ppm, 500 to 1000 ppm, 1000 to 5000 ppm, 1000 to 4500 ppm, 1000 to 4000 ppm, 1000 to 3500 ppm, 1000 to 3000 ppm, 1000 to 2500 ppm, 1000 to 2000 ppm, 1000 to 1 500ppm, 1500~5000ppm, 1500~4500ppm, 1500~4000ppm, 1500~3500ppm, 1500~3000ppm, 15 00~2500ppm, 1500~2000ppm, 2000~5000ppm, 2500~4500ppm, 2500~4000ppm, 2500~3500ppm , 2500-3000ppm, 3000-5000ppm, 3000-4500ppm, 3000-4000ppm, 3000-3500ppm, 3500-5000ppm, 3500-4500ppm, 3500-4000ppm, 4000-5000ppm, 4000-4500ppm, or 4500-5000ppm.

[0028] The ppm values ​​are based on the total weight of the lubricating oil composition.

[0029] Generally, the total amount of Ca and Mg present in the lubricating oil composition is about 5000 ppm or less.

[0030] In one embodiment, the hydrocarbyl-substituted salicylate is a long chain alkyl salicylate represented by the following general structure: [ka] In the formula, R″ is a C1-C30 (e.g., C13-C30) alkyl group, n is an integer from 1 to 4, and M is an alkaline earth metal (e.g., Ca or Mg).

[0031] In one embodiment of the present disclosure, the salicylates are prepared from alkylphenols with alkyl groups derived from C10-C40 isomerized normal alpha olefins (NAO) and having an isomerization level (i) of about 0.10 to about 0.40, about 0.10 to about 0.35, preferably about 0.10 to about 0.30, about 0.12 to about 0.30, about 0.12 to about 0.25, about 0.12 to about 0.23, about 0.12 to about 0.22, about 0.12 to about 0.20, about 0.13 to about 0.19, about 0.14 to about 0.18, or about 0.15 to about 0.17. Succinimide

[0032] The lubricating oil compositions of the present invention optionally contain a nitrogen-containing dispersant, including polyalkenyl succinimide dispersants such as those described herein. Typically, the nitrogen content of the lubricating oil composition from the nitrogen-containing dispersant is from about 0.010 wt. % to about 0.30 wt. %, such as from about 0.050 to about 0.25 wt. %, from about 0.050 to about 0.20 wt. %, and from about 0.050 to about 0.15 wt. %.

[0033] In one embodiment, the polyalkenyl bissuccinimide is a polyalkenyl-substituted succinic anhydride [ka] (wherein R is a polyalkenyl substituent derived from a polyalkene group having a number average molecular weight of about 500 to about 3000) with a polyamine. In one embodiment, R is a polyalkenyl substituent derived from a polyalkene group having a number average molecular weight of about 1000 to about 2500. In one embodiment, R is a polyisobutenyl substituent derived from polyisobutene having a number average molecular weight of about 500 to about 3000. In another embodiment, R is a polyisobutenyl substituent derived from polyisobutene having a number average molecular weight of about 1000 to about 2500.

[0034] Suitable polyamines for use in preparing bissuccinimide dispersants include polyalkylene polyamines. Such polyalkylene polyamines typically contain from about 2 to about 12 nitrogen atoms and from about 2 to 24 carbon atoms. Particularly suitable polyalkylene polyamines have the formula HN-(R'NH)xH, where R' is a linear or branched alkylene group having 2 or 3 carbon atoms and x is 1 to 9. Representative examples of suitable polyalkylene polyamines include ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, and heavy polyamines (e.g., Ethyleneamine E-100 available from Huntsman Company).

[0035] Typically, the polyalkenyl-substituted succinic anhydride is reacted with the polyamine at a temperature of about 130°C to about 220°C (e.g., 145°C to 175°C). The reaction can be carried out under an inert atmosphere, such as nitrogen or argon. Generally, the molar charge ratio between the polyamine and the polyalkenyl-substituted succinic anhydride is about 0.35:1 to about 0.6:1 (e.g., 0.4:1 to 0.5:1). As used herein, "molar charge of the polyamine relative to the polyalkenyl-substituted succinic anhydride" refers to the ratio of the number of moles of polyamine to the number of succinic acid groups in the succinic anhydride reactant.

[0036] One class of suitable polyalkenyl succinimides can be represented by: [ka] wherein R and R' are as described hereinabove, and y is 1-11. Post-treatment of polyalkenyl succinimide

[0037] In some embodiments, the succinimide dispersant may be post-treated with a reactive boron compound or an organic carbonate.

[0038] Suitable boron compounds that can be used as boron sources include, for example, boric acid, borate salts, and borate esters. Representative examples of boric acid include orthoboric acid, metaboric acid, and paraboric acid. Representative examples of borates include ammonium borates such as ammonium metaborate, ammonium tetraborate, ammonium pentaborate, and ammonium octaborate. Representative examples of borate esters include monomethyl borate, dimethyl borate, trimethyl borate, monoethyl borate, diethyl borate, triethyl borate, monopropyl borate, dipropyl borate, tripropyl borate, monobutyl borate, dibutyl borate, and tributyl borate.

[0039] Anti-wear agents The lubricating oil compositions disclosed herein may optionally contain one or more antiwear agents. Antiwear agents reduce wear of metal parts. Suitable antiwear agents include metal dihydrocarbyl dithiophosphates, such as zinc dihydrocarbyl dithiophosphate (ZDDP), which has the following structure: Zn[SP(=S)(OR1)(OR2)]2 wherein R1 and R2 can be identical to different hydrocarbyl radicals having 1 to 18 (e.g., 2 to 12) carbon atoms, including alkyl, alkenyl, aryl, arylalkyl, alkaryl, and alicyclic radicals. Particularly preferred as R1 and R2 groups are alkyl groups having 2 to 8 carbon atoms (e.g., the alkyl radical can be ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, n-pentyl, isopentyl, n-hexyl, isohexyl, or 2-ethylhexyl). To achieve oil solubility, the total number of carbon atoms (i.e., R1 + R2) is at least 5. Thus, the zinc dihydrocarbyl dithiophosphate can include a zinc dialkyldithiophosphate. The zinc dialkyldithiophosphate can be a primary or secondary zinc dialkyldithiophosphate, or a combination thereof. ZDDP may be present at up to 3 wt % (eg, 0.1 to 1.5 wt %, or 0.5 to 1.0 wt %) of the lubricating oil composition.

[0040] antioxidants In one embodiment, the lubricating oil composition may optionally include an antioxidant compound. In one embodiment, the antioxidant is an aromatic amine antioxidant. Typical aromatic amine antioxidants have at least two aromatic groups bonded directly to one amine nitrogen. Typical aromatic amine antioxidants have an alkyl substituent of at least six carbon atoms.

[0041] Examples of aromatic amine antioxidants useful herein include 4,4'-dioctyldiphenylamine, 4,4'-dinonyldiphenylamine, N-phenyl-1-naphthylamine, N-(4-tert-octylphenyl)-1-naphthylamine, N-(4-octylphenyl)-1-naphthylamine. The antioxidant may be present at 0.01 to 5 wt % (e.g., 0.1 to 2 wt %) of the lubricating oil composition.

[0042] Lubricating oil An oil of lubricating viscosity (sometimes referred to as a "base stock" or "base oil") is the primary liquid component of a lubricating oil, into which additives and possibly other oils are blended to produce, for example, the final lubricating oil (or lubricating oil composition). Base oils useful for making concentrates and for making lubricating oil compositions therefrom may be selected from natural (vegetable, animal, or mineral) and synthetic lubricating oils and mixtures thereof.

[0043] The oils used as base oils are selected or blended depending on the desired end use and additives in the finished oil to provide a lubricating oil composition having a desired engine oil grade, e.g., Society of Automotive Engineers (SAE). In one embodiment, the lubricating oil composition is a multigrade oil for heavy vehicles or passenger cars. The multigrade oil has a viscosity grade SAE of 0W-8, 0W-12, 0W-16, 0W-20, 0W-30, 0W-40, 0W-50, 0W-60, 5W, 5W-20, 5W-30, 5W-40, 5W-50, 5W-60, 10W, 10W-20, 10W-30, 10W-40, 10W-50, 15W, 15W-20, 15W-30, or 15W-40.

[0044] The definitions of base stock and base oil in this disclosure are the same as those found in American Petroleum Institute (API) Publication 1509 Annex E (“API Base Oil Interchangeability Guidelines for Passenger Car Motor Oils and Diesel Engine Oils”, December 2016). Group I base stocks contain less than 90% saturates and / or more than 0.03% sulfur and have a viscosity index of 80 or greater and less than 120, using the test methods set forth in Table E-1. Group II base stocks contain 90% or greater saturates and 0.03% or less sulfur and have a viscosity index of 80 or greater and less than 120, using the test methods set forth in Table E-1. Group III base stocks contain 90% or greater saturates and 0.03% or less sulfur and have a viscosity index of 120 or greater, using the test methods set forth in Table E-1. Group IV base stocks are polyalphaolefins (PAOs). Group V base stocks include all other base stocks not included in Group I, II, III, or IV.

[0045] Natural oils include animal oils, vegetable oils (e.g., castor oil and lard oil), and mineral oils. Animal and vegetable oils with favorable thermal oxidative stability can be used. Among natural oils, mineral oils are preferred. Mineral oils vary widely depending on their crude source, for example, whether they are paraffinic, naphthenic, or a mixture of paraffinic and naphthenic. Oils derived from coal or shale are also useful. Natural oils also vary depending on the methods used to produce and refine them, for example, their distillation range and whether they are straight-run, cracked, hydrorefined, or solvent extracted.

[0046] Synthetic oils include hydrocarbon oils, such as polymerized and copolymerized olefins (e.g., polybutylene, polypropylene, propylene-isobutylene copolymers, ethylene-olefin copolymers, and ethylene-alphaolefin copolymers). Polyalphaolefin (PAO) oil base stocks are commonly used synthetic hydrocarbon oils. Examples include C8-C 14 Olefins, e.g., C8, C 10 , C 12 , C 14 PAOs derived from olefins, or mixtures thereof, may be utilized.

[0047] Other useful fluids for use as base oils include unconventional or unconventional base stocks, which are preferably catalytically processed or synthetically prepared to provide high performance properties.

[0048] Unconventional or unconventional base stocks / base oils include one or more base stock(s) derived from gas-to-liquids (GTL) materials, as well as mixtures of isomerized / isomerization-dewaxed base stock(s) derived from natural wax or waxy feedstocks, mineral and / or non-mineral waxy raw stocks, such as slack wax, natural wax, and waxy stocks, such as gas oil, residues from hydrocracking of waxy fuels, waxy raffinates, hydrocracked oils, thermal cracked oils, or other mineral, mineral oil, or even non-petroleum-derived waxy materials, such as waxy materials obtained from coal liquids or shale oil, and mixtures of these base stocks. Other base oils include coal-to-liquids (CTL) products and alkylnaphthalenes.

[0049] The base oils for use in the lubricating oil compositions of the present disclosure can be any of a variety of oils corresponding to API Group I, Group II, Group III, Group IV, and Group V oils, and mixtures thereof, with API Group II, Group III, Group IV, and Group V oils, and mixtures thereof, being preferred, and Group III to Group V base oils being more preferred due to their superior volatility, stability, viscosity, and detergency characteristics.

[0050] The lubricating oil composition has a high temperature shear viscosity (HTHS) at 150°C of 3.7 cP or less, for example, 3.6 cP or less, 3.5 cP or less, 3.4 cP or less, 3.3 cP or less, 3.2 cP or less, 3.1 cP or less, 3.0 cP or less, 2.9 cP or less, 2.8 cP or less, 2.7 cP or less, 2.6 cP or less, 2.5 cP or less, 2.4 cP or less, 2.3 cP or less, 2.2 cP or less, 2.1 cP or less, 2.0 cP or less, 1.9 cP or less, 1.8 cP or less, 1.7 cP or less, 1.6 cP or less, 1.5 cP or less, 1.4 cP or less, 1.3 cP or less, 1.2 cP or less, 1.1 cP or less, 1.0 cP or less, 1.0 to 2.9 cP, 1.3 to 2.9 cP), 1.0 to 2.6 cP, 1.3 to 2.6 cP, 1.0 cP to 2.3 cP, 1.3 cP to 2.3 cP, 1.0 cP to 2.0 cP, 1.3 cP to 2.3 cP, 1.0 cP to 1.7 cP, or 1.3 cP to 1.7 cP.

[0051] The lubricating oil composition may have a viscosity index of at least 135 (e.g., 135-400, or 135-250), at least 150 (e.g., 150-400, 150-250), at least 165 (e.g., 165-400, or 165-250), at least 190 (e.g., 190-400, or 190-250), or at least 200 (e.g., 200-400, or 200-250). If the viscosity index of the lubricating oil composition is less than 135, it may be difficult to improve fuel efficiency while maintaining the HTHS viscosity at 150°C. If the viscosity index of the lubricating oil composition is greater than 400, evaporation characteristics may be reduced, and defects due to insufficient additive solubility and insufficient compatibility with sealing materials may occur.

[0052] The base oil has a kinematic viscosity (ASTM D445) of 1.4 to 20 mm at 100°C. 2 / s, for example, 3 to 12 mm 2 / s, e.g. 3~11mm 2 / s, 3 to 10 mm 2 / s, 3~9mm 2 / s, 3~8mm 2 / s, 3-7mm 2 / s, 3~6mm2 / s, 3~5mm 2 / s, 3~4mm 2 / s, 4~12mm 2 / s, 4~11mm 2 / s, 4~10mm 2 / s, 4~9mm 2 / s, 4~8mm 2 / s, 4~7mm 2 / s, 4~6mm 2 / s, 4~5mm 2 / s, 5-12mm 2 / s, 5-11mm 2 / s, 5-10mm 2 / s, 5-9mm 2 / s, 5-8mm 2 / s, 5-7mm 2 / s, 5-6mm 2 / s, 6~12mm 2 / s, 6-11mm 2 / s, 6-10mm 2 / s, 6~9mm 2 / s, 6-8mm 2 / s, 6-7mm 2 / s, 7~12mm 2 / s, 7~11mm 2 / s, 7~10mm 2 / s, 7~9mm 2 / s, 7~10mm 2 / s, 7~9mm 2 / s, 7~8mm 2 / s, 8~12mm 2 / s, 8~11mm 2 / s, 8~10mm 2 / s, 8~9mm 2 / s, 9~12mm 2 / s, 9-11mm 2 / s, 9~10mm 2 / s, 10-12mm 2 / s, 10-11mm 2 / s, or 11-12 mm 2 / s range.

[0053] In some embodiments, the lubricating oil composition contains 0.8 to 1.5 wt.% ash, e.g., 0.8 to 1.4 wt.%, 0.8 to 1.3 wt.%, 0.8 to 1.2 wt.%, 0.8 to 1.1 wt.%, 0.8 to 1.0 wt.%, 0.8 to 0.9 wt.%, 0.9 to 1.5 wt.%, 0.9 to 1.4 wt.%, 0.9 to 1.3 wt.%, 0.9 to 1.2 wt.%, 0.9 to 1.1 wt.%, 0.9 to 1.0 wt.% , 1.0 to 1.5 weight%, 1.0 to 1.4 weight%, 1.0 to 1.3 weight%, 1.0 to 1.2 weight%, 1.0 to 1.1 weight%, 1.1 to 1.5 weight%, 1.1 to 1.4 weight%, 1.1 to 1.3 weight%, 1.1 to 1.2 weight%, 1.2 to 1.5 weight%, 1.2 to 1.4 weight%, 1.2 to 1.3 weight%, 1.3 to 1.5 weight%, 1.3 to 1.4 weight%, and 1.4 to 1.5 weight% ash.

[0054] In some embodiments, the lubricating oil composition contains more than 600 ppm phosphorus, for example, more than 650 ppm, more than 700 ppm, more than 750 ppm, more than 800 ppm, more than 850 ppm, more than 900 ppm, more than 950 ppm, and more than 1000 ppm phosphorus.

[0055] Other additives The lubricating oil composition of the present invention can also contain conventional lubricating oil additives to provide auxiliary functions, resulting in a finished lubricating oil composition in which these additives are dispersed or dissolved. For example, the lubricating oil composition can be mixed with antioxidants, ashless dispersants, antiwear agents, rust inhibitors, anti-haze agents, emulsion separators, friction modifiers, metal deactivators, pour point depressants, viscosity modifiers, antifoam agents, cosolvents, package compatibility agents, corrosion inhibitors, dyes, extreme pressure agents, etc., as well as mixtures thereof. Various additives are known and commercially available. These additives or their analogous compounds can be used to prepare the lubricating oil composition of the present invention by conventional blending procedures.

[0056] Each of the foregoing additives, when used, is used in a functionally effective amount to impart the desired characteristics to the lubricating oil. Thus, for example, if the additive is an ashless dispersant, a functionally effective amount of the ashless dispersant is an amount sufficient to impart the desired dispersant characteristics to the lubricating oil. Generally, the concentration of each of these additives, when used, can range from about 0.001 to about 20% by weight, for example, from about 0.01 to about 10% by weight, unless otherwise specified.

[0057] The following non-limiting examples are illustrative of the present invention. A brief description of how the examples were prepared is provided. [Example]

[0058] Reference formulation All samples (Examples 1-7) contain a reference formulation, which is a heavy-duty diesel lubricating oil composition of SAE 10-30W viscosity grade, prepared by blending the following components: a) Mixtures of borated and non-borated succinimides b) Alkylated diphenylamine antioxidants c) Mixture of primary and secondary ZnDTP d) Detergent systems containing Ca / Mg sulfonates, Ca phenates, and / or Ca / Mg salicylates

[0059] The remainder of the lubricating oil composition comprises base oil, viscosity index improver, and pour point depressant.Each sample was subjected to the NOx conversion bench test described below. NOx conversion bench test

[0060] This test measures the loss of NOx conversion in an SCR catalyst after contamination with lubricating oil. Prior to conducting the SCR test, the catalyst must be prepared, which involves taking a solid vanadium EU6 catalyst monolith, crushing the material, filtering, hydrothermally aging, and impregnating / calcining it.

[0061] After crushing and filtering the catalyst material, it was immersed in an oil sample and heated and filtered until no visible oil remained. The oil-impregnated catalyst was calcined under positive airflow to remove hydrocarbons. SCR testing was conducted under typical diesel exhaust conditions (temperatures were ramped from 175°C to 550°C). More specifically, the SCR catalyst material was contacted with a simulated feed gas mixture consisting of NO (500 ppm), NH3 (500 ppm), HO (5%), O2 (10%), and the balance N2.

[0062] SCR operation was carried out at 10 different temperature conditions (200, 220, 240, 260, 280, 300, 320, 350, 400, and 500°C). ATS conversion (NOx conversion efficiency) was evaluated from the outlet value based on ICP analysis. [Table 1]

[0063] Lubricants with a lower TBN may exhibit better ATS performance in some cases, but the trade-off is that the low TBN may result in poor detergency performance and may not be suitable for engine lubrication. From a formulation standpoint, it is important to carefully balance TBN and ATS.

[0064] For the sake of brevity, only certain ranges are explicitly disclosed herein. However, a range from any lower limit may be combined with any upper limit to recite a range not explicitly stated, and similarly, a range from any lower limit may be combined with any other lower limit to recite a range not explicitly stated, and similarly, a range from any upper limit may be combined with any other upper limit to recite a range not explicitly stated. Furthermore, a range includes every point or individual value between its endpoints, even if not explicitly recited. Thus, every point or individual value may be combined with any other point or individual value, or with any other lower or upper limit, to serve as its own lower or upper limit, to recite a range not explicitly stated.

[0065] Similarly, the term "comprising" is considered synonymous with the term "including." Similarly, whenever the transitional phrase "comprising" appears before a composition, element, or group of elements, it is understood to also contemplate the same composition or group of elements having the transitional phrase "consisting essentially of," "consisting of," "selected from the group consisting of," or "is" preceding the description of the composition, element, or group of elements, and vice versa.

[0066] As used herein, the terms "a" and "the" are understood to encompass the plural as well as the singular.

[0067] Various terms are defined above. To the extent that a term used in the claims is not defined above, it should be given the broadest definition given to that term by one skilled in the relevant art, as reflected in at least one printed publication or issued patent. Furthermore, all patents, test methods, and other documents cited in this application are incorporated by reference in their entirety to the extent such disclosure is not inconsistent with this application and in all jurisdictions where such incorporation is permitted.

[0068] The foregoing description of the present disclosure illustrates and describes the present disclosure. Moreover, while the present disclosure shows and describes only preferred embodiments, it will be understood that the present disclosure is capable of use in various other combinations, modifications, and environments, as noted above, and that changes or modifications are possible within the scope of the concepts expressed herein, commensurate with the above teachings and / or skill or knowledge of the relevant art. While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the present disclosure may be devised without departing from the basic scope thereof, which scope is determined by the claims that follow.

[0069] Where combinations, subsets, groups, etc. of elements (e.g., combinations of components in a composition or combinations of steps in a method) are disclosed, it is understood that each of the various individual and collective combinations, and permutations of those elements is specifically contemplated and described herein, even if specific reference to each is not explicitly disclosed.

[0070] The embodiments described herein above are also intended to further explain the best mode known for carrying out the invention and to enable others skilled in the art to utilize the present disclosure in such or other embodiments, with various modifications as required for a particular application or use. Therefore, the description is not intended to be limited to the forms disclosed herein. Also, it is intended that the appended claims be construed to include alternative embodiments.

Claims

1. 1. A method for reducing catalyst poisoning in a diesel engine aftertreatment system equipped with a selective catalytic reduction device, the method comprising: a major amount of oil of lubricating viscosity; lubricating said engine with a lubricating oil composition comprising a Ca or Mg salicylate detergent; The method, wherein the lubricating oil composition does not contain a Ca sulfonate-based detergent.

2. 2. The method of claim 1, wherein the lubricating oil composition contains 500 to 5000 ppm of Ca from the Ca salicylate detergent.

3. 10. The method of claim 1, wherein the lubricating oil composition contains 500 to 5000 ppm Mg from the Mg salicylate detergent.

4. 10. The method of claim 1, wherein the lubricating oil composition contains 0.8 to 1.5 wt. % ash.

5. 10. The method of claim 1, wherein the lubricating oil composition contains greater than 600 ppm phosphorus.

6. 10. The method of claim 1, wherein the lubricating oil composition contains 500 to 5000 ppm of Ca and Mg.

7. 10. The method of claim 1, wherein the lubricating oil composition contains no more than 50 ppm of Ca or Mg provided by a sulfonate-based detergent.

8. 1. Use of a lubricating oil composition to reduce catalyst poisoning in a diesel engine aftertreatment system equipped with a selective catalytic reduction device, comprising: The lubricating oil composition comprises a major amount of oil of lubricating viscosity; Contains a Ca or Mg salicylate detergent, The above-mentioned use, wherein the lubricating oil composition does not contain a sulfonate-based detergent.

9. 9. The use according to claim 8, wherein the lubricating oil composition contains 500 to 5000 ppm of Ca derived from a Ca salicylate based detergent.

10. 9. The use of claim 8, wherein the lubricating oil composition contains 500 to 5000 ppm Mg derived from a Mg salicylate detergent.

11. The use according to claim 8, wherein the lubricating oil composition contains 0.8 to 1.5 wt. % ash.

12. 9. The use of claim 8, wherein the lubricating oil composition contains more than 600 ppm phosphorus.

13. The use according to claim 8, wherein the lubricating oil composition contains 500 to 5000 ppm of Ca and Mg.

14. 9. The use of claim 8, wherein the lubricating oil composition contains 50 ppm or less of Ca or Mg provided from a sulfonate-based detergent.

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