Patent Application
20080086935
By “gasoline performance additive” herein is meant any one or more chemicals useful in the present disclosure for dissolving or dispersing in a gasoline fuel.
By “corrosion” herein is meant any degradation, rusting, weakening, deterioration, softening, and the like of an engine surface or a part or component of an engine or an engine component or part due to exposure to an ethanol-containing fuel.
By “corrosion inhibition” or “reducing corrosion” herein is meant any improvement in minimizing, reducing, eliminating or preventing corrosion.
By “ethanol” herein is meant ethyl alcohol, the chemical compound C2H5OH. This can arise in or be provided in many qualities or grades, such a commercial of fuel grade, as well as pure or reagent grade ethanol, and can be derived from any source such as but not limited to petroleum refinery streams, distillation cuts, and bio-derived (e.g. bioethanol from corn).
By “corrosion inhibitor” herein is meant at least the following: succinimide dispersants, succinamide dispersants, amides, Mannich base dispersants, and polyetheramine dispersants, phenolics, hindered phenolics, aryl amines, diphenyl amines, monocarboxylic acids, dicarboxylic acids, p-phenylenediamine and dicyclohexylamine, oxylated alkylphenolic resins, formaldehyde polymer with 4-(1,1-dimethylethyl)phenol, methyloxirane and oxirane, octane enhancer materials, monoesters, diesters, ketones, ethers, diethers, polyethers, glycols, glymes, oxiranes, C1-C8 aliphatic hydrocarbons, butylene oxide, propylene oxide, ethylene oxide, epoxides, butane, pentane, xylene, nitrous oxide, nitromethane, phenates, salicylates, sulfonates, nonylphenol ethoxylates, and fuel-soluble alkali detergents and alkaline earth metal-containing detergents, Thus, there is provided herein in one embodiment a method to reduce corrosion in an internal combustion engine, said method comprising combusting in said engine a fuel composition comprising gasoline, ethanol and at least one fuel additive, said additive being selected from the group consisting succinimide dispersants, succinamide dispersants, amides, Mannich base dispersants, and polyetheramine dispersants, whereby corrosion is reduced relative to the corrosion when combusting a fuel composition without ethanol.
In another embodiment, the fuel additive useful to reduce corrosion can be selected from phenolics, hindered phenolics, aryl amines, diphenyl amines, monocarboxylic acids, dicarboxylic acids, polycarboxylic acids, an oxylated alkylphenolic resin, and formaldehyde polymer with 4-(1,1-dimethylethyl)phenol, methyloxirane and oxirane, octane enhancer materials, monoesters, diesters, ethers, ketones, diethers, polyethers, glymes, glycols, corrosion inhibitor materials, oxiranes, C1-C8 aliphatic hydrocarbons, butylene oxide, propylene oxide, ethylene oxide, epoxides, butane, pentane, xylene, nitrous oxide, nitromethane, phenates, salicylates, sulfonates, nonylphenol ethoxylates, and fuel-soluble alkali detergents and alkaline earth metal-containing detergents.
In another embodiment herein, heterocyclic aromatics for nonferrous metal corrosion protection are useful herein for use with ethanol-containing fuels. These can include, for example and without limitation, p-phenylenediamine and dicyclohexylamine. These are particularly effective in reducing corrosion by neutralizing acidic components that can get into the fuel from the ethanol or bioethanol sources.
Similarly, acidic additives are useful in reducing corrosion by neutralizing basic materials and contaminants that can enter the fuel blend from the ethanol or bioethanol. In this regard, monocarboxylic acids, dicarboxylic acids, and polycarboxylic acids are particularly effective.
Rust inhibitors have been used in gasoline fuels not containing ethanol. However, the introduction of E100 fuels and blends such as E85 has created additional problems of rust problems in engines and equipment and components contacting the ethanol fuel. Rust inhibitors useful here in preventing corrosion of surfaces exposed to ethanol-containing fuels can include, for example tall oil fatty acids, dodecenyl succinic acid (DDSA) and mono carboxylic acids, such as oleic acid. Thus, there is provided herein a composition to reduce corrosion in an internal combustion engine combusting an ethanol-containing fuel, said composition comprising gasoline, ethanol, and one or more materials selected from the group consisting of tall oil fatty acids, dodecenyl succinic acid, and oleic acid plus N,N dimethylcyclohexylamine.
Copper and lead bearing corrosion inhibitors may be used, but are typically not required with the formulation of the present invention. Typically such compounds are the thiadiazole polysulfides containing from 5 to 50 carbon atoms, their derivatives and polymers thereof. Derivatives of 1,3,4 thiadiazoles such as those described in U.S. Pat. Nos. 2,719,125; 2,719,126; and 3,087,932; are typical. Other similar materials are described in U.S. Pat. Nos. 3,821,236; 3,904,537; 4,097,387; 4,107,059; 4,136,043; 4,188,299; and 4,193,882. Other additives are the thio and polythio sulfenamides of thiadiazoles such as those described in UK Patent Specification No. 1,560,830. Benzotriazoles derivatives also fall within this class of additives. When these compounds are included in the fuel composition, they are typically present in an amount not exceeding 0.2 wt. % active ingredient.
Some engines have copper-containing or silver-containing components or devices that can contact the fuel supply. Such components can experience corrosion, particularly when the fuel contains, or is, ethanol. In certain instances, the ethanol can carry significant dissolved water which can exacerbate the corrosion problem posed by the ethanol alone. To address corrosion reduction on such components, the present disclosure provides a method to reduce corrosion of copper and/or silver in an engine having copper or silver components and combusting an ethanol-containing fuel by adding to the ethanol or to the fuel at least one additive selected from succinimide dispersants, succinamide dispersants, amides, Mannich base dispersants, and polyetheramine dispersants, phenolics, hindered phenolics, aryl amines, diphenyl amines, monocarboxylic acids, dicarboxylic acids, polycarboxylic acids, p-phenylenediamine and dicyclohexylamine, an oxylated alkylphenolic resin, formaldehyde polymer with 4-(1,1-dimethylethyl)phenol, methyloxirane and oxirane, octane enhancer materials, monoesters, diesters, ethers, diethers, polyethers, glycols, glymes, oxiranes, C1-C8 aliphatic hydrocarbons, butylene oxide, propylene oxide, ethylene oxide, epoxides, butane, pentane, xylene, nitrous oxide, nitromethane, phenates, salicylates, sulfonates, nonylphenol ethoxylates, and fuel-soluble alkali detergents and alkaline earth metal-containing detergents, whereby the copper and/or silver component(s) have/has reduced corrosion relative to the corrosion observed when the copper and/or silver component(s) are/is exposed to a fuel without ethanol.
The following examples further illustrate aspects of the present disclosure but do not limit the present disclosure.
To an E85 fuel can be added 1.0 percent by weight of dodecenyl succinic acid (DDSA) and the fuel formulation can be supplied to and combusted in an internal combustion spark ignited engine. The corrosion exhibited on the engine surfaces exposed to the fuel blend plus DDSA will display less corrosion after 5,000 miles than the corrosion exhibited on the engine surfaces after 5,000 miles of exposure to the same fuel blend without the DDSA.
To an E85 fuel can be added 2.0 percent by weight of oleic acid and the fuel formulation can be supplied to and combusted in an internal combustion spark ignited engine. The corrosion exhibited on the engine surfaces exposed to the fuel blend plus oleic acid will display less corrosion after 5,000 miles than the corrosion exhibited on the engine surfaces after 5,000 miles of exposure to the same fuel blend without the oleic acid.
To an E85 fuel can be added 2.0 percent by weight of a condensation product of alpha halogenated mono-carboxylic acid with 2,5-dimercapto-1,3,4-thiadiazole and the fuel formulation can be supplied to and combusted in an internal combustion spark ignited engine. The corrosion exhibited on the engine surfaces exposed to the fuel blend plus the thiadiazole derivative will display less corrosion after 5,000 miles than the corrosion exhibited on the engine surfaces after 5,000 miles of exposure to the same fuel blend without the thiadiazole derivative.
To an E85 fuel can be added 1.0 percent by weight of the reaction product of oleic acid and 2,5-dimercapto-1,3,4-thiadiazole and the fuel formulation can be supplied to and combusted in an internal combustion spark ignited engine. The corrosion exhibited on the engine surfaces exposed to the fuel blend plus the thiadiazole derivative will display less corrosion after 3,000 miles than the corrosion exhibited on the engine surfaces after 3,000 miles of exposure to the same fuel blend without the thiadiazole derivative.
In addition to Examples 1-4 above, the benefits and advantages of the present invention will be observed by testing the compositions disclosed herein in ASTM D665A corrosion test. Further confirmation of the present invention is provided by performing the test NACE TM 0172 on the compositions disclosed herein and comparing the results to fuel compositions not containing alcohol or not containing the presently disclosed additives.
The table below provide illustration of some desired additive combinations for various ethanol-containing fuels whereby corrosion might be controlled or reduced in an engine combusting the ethanol-containing fuel.
Another test to demonstrate the benefit of the present disclosure involved waer scar measurements, shown in Table 4.
Table 4 shows the results of wear scar testing in which a median wear scar diameter MWSD) is reported. Run 1 was E85 using New Energy Ethanol and this baseline MWSD was 605. When HiTEC® 4142 (oleic acid plus N,N dimethylcyclohexylamine) was added as a corrosion inhibitor, the MWSD was reduced to 445. Changing the corrosion inhibitor in the E85 fuel to DDSA (50% in A150 solvent) gave a slightly higher value of 540 but still improved over the baseline for E85. Using ADM Ethanol in the E85 produced even further reduction in the wear scar, probably due to the corrosion inhibitor (DCI-11) in the ethanol. This Table shows the benefit in wear scar reduction and hence in reducing wear in an engine achieved by incorporation of dodecenyl succinic acid and/or oleic acid plus N,N dimethylcyclohexylamine into an ethanol-containing gasoline fuel blend.
Other embodiments of the present disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. As used throughout the specification and claims, “a” and/or “an” may refer to one or more than one. Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight, percent, ratio, reaction conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the specification and claims are approximations that may vary depending upon the desired properties sought to be obtained by the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the disclosure are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.
