EP2459687A1 - Biodiesel and biodiesel blend fuels - Google Patents

Biodiesel and biodiesel blend fuels

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Publication number
EP2459687A1
EP2459687A1 EP10804912A EP10804912A EP2459687A1 EP 2459687 A1 EP2459687 A1 EP 2459687A1 EP 10804912 A EP10804912 A EP 10804912A EP 10804912 A EP10804912 A EP 10804912A EP 2459687 A1 EP2459687 A1 EP 2459687A1
Authority
EP
European Patent Office
Prior art keywords
nitrate
tert
butyl
biodiesel
butylphenol
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP10804912A
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German (de)
French (fr)
Other versions
EP2459687A4 (en
Inventor
Marc-Andre Poirier
Paul P. Wells
Paul Bessonette
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ExxonMobil Technology and Engineering Co
Original Assignee
ExxonMobil Research and Engineering Co
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Publication of EP2459687A1 publication Critical patent/EP2459687A1/en
Publication of EP2459687A4 publication Critical patent/EP2459687A4/en
Withdrawn legal-status Critical Current

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    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C10L1/14—Organic compounds
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C10L1/14—Organic compounds
    • C10L1/16—Hydrocarbons
    • C10L1/1616—Hydrocarbons fractions, e.g. lubricants, solvents, naphta, bitumen, tars, terpentine
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C10L1/14—Organic compounds
    • C10L1/18—Organic compounds containing oxygen
    • C10L1/182—Organic compounds containing oxygen containing hydroxy groups; Salts thereof
    • C10L1/183—Organic compounds containing oxygen containing hydroxy groups; Salts thereof at least one hydroxy group bound to an aromatic carbon atom
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C10L1/14—Organic compounds
    • C10L1/18—Organic compounds containing oxygen
    • C10L1/182—Organic compounds containing oxygen containing hydroxy groups; Salts thereof
    • C10L1/183—Organic compounds containing oxygen containing hydroxy groups; Salts thereof at least one hydroxy group bound to an aromatic carbon atom
    • C10L1/1832—Organic compounds containing oxygen containing hydroxy groups; Salts thereof at least one hydroxy group bound to an aromatic carbon atom mono-hydroxy
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C10L1/14—Organic compounds
    • C10L1/18—Organic compounds containing oxygen
    • C10L1/19—Esters ester radical containing compounds; ester ethers; carbonic acid esters
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C10L1/14—Organic compounds
    • C10L1/22—Organic compounds containing nitrogen
    • C10L1/222—Organic compounds containing nitrogen containing at least one carbon-to-nitrogen single bond
    • C10L1/2222—(cyclo)aliphatic amines; polyamines (no macromolecular substituent 30C); quaternair ammonium compounds; carbamates
    • C10L1/2225—(cyclo)aliphatic amines; polyamines (no macromolecular substituent 30C); quaternair ammonium compounds; carbamates hydroxy containing
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C10L1/14—Organic compounds
    • C10L1/22—Organic compounds containing nitrogen
    • C10L1/222—Organic compounds containing nitrogen containing at least one carbon-to-nitrogen single bond
    • C10L1/223—Organic compounds containing nitrogen containing at least one carbon-to-nitrogen single bond having at least one amino group bound to an aromatic carbon atom
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C10L1/14—Organic compounds
    • C10L1/22—Organic compounds containing nitrogen
    • C10L1/23—Organic compounds containing nitrogen containing at least one nitrogen-to-oxygen bond, e.g. nitro-compounds, nitrates, nitrites
    • C10L1/231—Organic compounds containing nitrogen containing at least one nitrogen-to-oxygen bond, e.g. nitro-compounds, nitrates, nitrites nitro compounds; nitrates; nitrites
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L10/00—Use of additives to fuels or fires for particular purposes
    • C10L10/12—Use of additives to fuels or fires for particular purposes for improving the cetane number
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L2200/00—Components of fuel compositions
    • C10L2200/04—Organic compounds
    • C10L2200/0461—Fractions defined by their origin
    • C10L2200/0469—Renewables or materials of biological origin
    • C10L2200/0476—Biodiesel, i.e. defined lower alkyl esters of fatty acids first generation biodiesel
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L2230/00—Function and purpose of a components of a fuel or the composition as a whole
    • C10L2230/08—Inhibitors
    • C10L2230/081—Anti-oxidants

Definitions

  • the invention provides fuel compositions comprising synergistic combinations of a biodiesel or biodiesel blend, an antioxidant comprising a mixture of at least one diphenol and at least one sterically hindered phenol, and a cetane improver.
  • Biodiesel is the name for a variety of ester-based oxygenated fuels made from vegetable oils, fats, greases, or other sources of triglycerides.
  • Biodiesel is a nontoxic and biodegradable blendstock which may be blended with petroleum diesel provided relevant specifications are met. Blends of biodiesel with petroleum diesel can substantially reduce the emission levels and toxicity of diesel exhaust. Biodiesel has been designated as an alternative fuel by the United States Department of Energy and the United States Department of Transportation, and is registered with the United States Environmental
  • Biodiesel fuels typically contain unsaturated fatty acid esters that can easily oxidize in the presence of oxygen, especially if UV light, and/or trace metals are also present. The products formed from this oxidation give rise to sediment and gum formation within the fuel that can lead to corrosion and plugging of filters, pumps and fuel injectors which utilize fuel containing biodiesel.
  • the fuel compositions comprise: (1) between about 0.01% to about 1% by volume of a cetane improver; (2) either (a) a biodiesel, or (b) a biodiesel blend comprising about 2% to about 98% by volume of a biodiesel and about 2% to about 98% by volume of a petroleum distillate; and (3) an antioxidant comprising a mixture of at least one diphenol and at least one sterically hindered phenol, wherein (a) the amount of the antioxidant is (i) between about 20 milligrams per kilogram of the biodiesel or biodiesel blend to about 10,000 milligrams per kilogram of the biodiesel or biodiesel blend, or (ii) is between about 16 milligrams per liter of the biodiesel or biodiesel blend to about 8,000 milligrams per liter of the biodiesel or biodiesel blend, and (b) wherein the volumetric ratio of the diphenol(s) to the sterically hindered
  • the fuel compositions described herein facilitate a wider use of biodiesels and biodiesel blends. Further, the fuel compositions described herein should avoid the corrosion, plugging, and sediment and gum formation associated with known biodiesels and biodiesel blends.
  • FIGURE 1 and FIGURE 2 illustrate that the addition of a cetane improver to biodiesel fuels reduced their oxidation stability measured by the Rancimat test method (prEN 15751), as determined in the experiment of
  • Example 1 As described in Examples 1-4 hereinafter, the fuels tested were Fuel 1 (5% by volume of soybean methyl ester plus 95% by volume of petroleum diesel fuel), Fuel 2 (99.7% by volume of Fuel 1 + 0.3% by volume of 2- ethylhexyl nitrate), and variants of Fuel 2.
  • FIGURE 3 illustrates the oxidation-stabilizing effect of adding a diphenol and a sterically hindered phenol to biodiesel fuels containing a cetane improver, as determined in the experiment of Example 2.
  • FIGURE 4 illustrates that the presence of a diphenol and a sterically hindered phenol did not significantly affect the ignition quality of biodiesel fuels containing a cetane improver, as determined in the experiment of Example 3.
  • FIGURE 5 illustrates that a benzoquinone proved ineffective as an oxidation-stabilizing substitute for a diphenol, as determined in the experiment of Example 4.
  • Biodiesel means a composition that can be used as a fuel for diesel engines and that contains at least about 50% by weight of esters of saturated and unsaturated fatty acids, including fatty acid methyl esters (FAME's), fatty acid ethyl esters (FAEE' s), propyl esters of fatty acids, or combinations of two or more methyl, ethyl, and propyl esters.
  • FAME's fatty acid methyl esters
  • FEE's fatty acid ethyl esters
  • propyl esters of fatty acids or combinations of two or more methyl, ethyl, and propyl esters.
  • a biodiesel comprises between about 50% to about 99% by weight of methyl esters of saturated and unsaturated fatty acids, where the methyl esters of saturated and unsaturated fatty acids include C 8 -C 24 fatty acid methyl esters, where C 8 -C 24 indicates the number of carbons in the original fatty acid.
  • Biodiesels can be made by transesterification of one or more vegetable oils, animal fats, or mixtures thereof (e.g. soybean oil, rapeseed oil, palm oil, canola oil, sunflower oil, olive oil, corn oil, tallow oil, coconut oil, jatropha oil, yellow grease, animal fats, used cooking oil, and mixtures thereof) with an alcohol such as methanol or ethanol.
  • the fatty acid esters are largely unsaturated and comprise a rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, or a mixture thereof.
  • a 100% biodiesel (B lOO) should meet ASTM D6751 and/or EN 14214 specifications.
  • Biodiesel blends biodiesel blended with a petroleum distillate such as diesel fuel
  • Bx a petroleum distillate such as diesel fuel
  • Petroleum distillate includes naphtha or middle distillates including kerosene and diesel.
  • a non-limiting example of a “diesel fuel” or "a diesel” is composed of a mixture Of C 9 -C 24 hydrocarbons that comprise about 50% to about 95% by volume of aliphatic hydrocarbons, of which about 0% to about 50% by volume are cycloparaffins, about 0% to about 5% by volume of olefinic hydrocarbons, and about 5% to about 50% by volume of aromatic hydrocarbons, and which boil at between about 280 0 F (138°C) and 75O 0 F (399 0 C).
  • a non-limiting example of a "kerosene” comprises about 5% to about 50% by volume of an aromatic fraction, about 0% to about 50% by volume of a cycloparaffin fraction, and about 0% to about 5% by volume of an olefinic fraction, with the rest comprising aliphatic hydrocarbons.
  • An aromatics fraction can contain methyl aromatics and non-methyl alkyl aromatics.
  • Non-limiting examples of non-methyl alkyl aromatics include molecules such as,alkyl benzenes, dialkylbenzenes, alkylnaphthalenes, alkyl biphenyls, and alkyl phenanthrenes, and the like, in which one or more linear or branched alkyl groups containing two or more carbons is bonded to the aromatic ring.
  • Non-limiting examples of methyl aromatics include aromatic molecules such as methylnaphthalene, dimethylnaphthalenes, and the like.
  • a cycloparaffin fraction consists of cycloalkanes or molecules containing at least one cycloalkane ring.
  • Non-limiting examples of components of the cycloparaffin fraction include alkylcyclohexanes and alkylcyclopentanes.
  • An olefinic fraction can contain linear, branched, and cyclo-olefins.
  • Non-limiting examples of components of the olefinic fraction include dodecenes and hexadecenes.
  • a "cetane improver” includes but is not limited to 2-ethylhexyl nitrate (EHN) (e.g. HITEC® 4103, Ethyl Corp., Richmond, VA), cyclohexyl nitrate, di- tert-butyl peroxide, methyl nitrate, ethyl nitrate, n-propyl nitrate, isopropyl nitrate, allyl nitrate, n-butyl nitrate, isobutyl nitrate, sec-butyl nitrate, tert-butyl nitrate, n-amyl nitrate, isoamyl nitrate, 2-amyl nitrate, 3-amyl nitrate, tert-amyl nitrate, n-hexyl nitrate, 2-ethylhexyl nitrate, n-hept
  • a "diphenol” includes but is not limited to hydroquinone (HQ), mono and dialkylated hydroquinones having one or two C 1 -C 8 alkyl groups (e.g. tert- butylhydroquinone (TBHQ), 2-tert-butyl- 1 ,4-hydroquinone, 2,5-di-tert-butyl- 1,4-hydroquinone, methylhydroquinone (toluhydroquinone or THQ), 2,5-di-tert.- octylhydroquinone (DOH)), and mixtures thereof.
  • HQ hydroquinone
  • TBHQ tert- butylhydroquinone
  • 2-tert-butyl- 1 ,4-hydroquinone 2,5-di-tert-butyl- 1,4-hydroquinone
  • methylhydroquinone toluhydroquinone or THQ
  • a "sterically hindered phenol” includes but is not limited to mono, di, and trialkylated phenols such as 2, 6-di-tert-butylphenol, 2, 4-di-tert- butylphenol, 2, 6-di-tert-butyl-4-methylphenol (BHT), 2-tert-butylphenol, 2, 4, 6-tri-tert-butylphenol, 2, 6-di-tert-butyl-4-dimethylaminomethylphenol, and mixtures thereof.
  • BHT 2, 6-di-tert-butylphenol
  • BHT 2, 6-di-tert-butyl-4-methylphenol
  • sterically hindered phenols that can be used in the fuel compositions described herein include Ethanox® 4703 and 4733 (Albermarle Corp., Baton Rouge, LA), Westco® AO-29 (Western Reserve Chemical, Stow, OH), Baynox® (Lanxess, Leverkusen, DE), and Ionol® BF 150 and BF 200 (Oxiris Chemicals S. A.., Barcelona, ES).
  • the diphenol and sterically hindered phenol are selected, respectively, from a compound of formula (I) and a compound of formula (II):
  • fuel compositions of the invention may also include an aromatic amine antioxidant (e.g. a phenylediamine- type antioxidant) such as N, N'-di-sec-butyl-p-phenylenediamine, 4-isopropylaminodiphenylamine, phenyl- naphthyl amine, and ring-alkylated diphenylamines.
  • aromatic amine antioxidant e.g. a phenylediamine- type antioxidant
  • aromatic amine antioxidant such as N, N'-di-sec-butyl-p-phenylenediamine, 4-isopropylaminodiphenylamine, phenyl- naphthyl amine, and ring-alkylated diphenylamines.
  • Fuel compositions of the invention may also include performance additives such as cold flow additives, cloud point depressants, biocides, conductivity improvers, corrosion inhibitors, metal deactivators, and engine cleaning agents.
  • performance additives such as cold flow additives, cloud point depressants, biocides, conductivity improvers, corrosion inhibitors, metal deactivators, and engine cleaning agents.
  • such additives are present in an amount which ranges from about 0.001 to about 2.0% by weight of the fuel composition.
  • the fuel compositions comprise: (1) between about 0.01% to about 1%, in some aspects between about 0.01% to about 0.75%, in some aspects between 0.01% to about 0.5%, and in some aspects between about 0.01% to about 0.35% by volume of a cetane improver; (2) either (a) a biodiesel comprising at least about 50% by weight, in some aspects at least about 60% by weight, in some aspects at least about 70% by weight, in some aspects at least about 80% by weight, in some aspects at least about 90% by weight, in some aspects at least about 95% by weight of esters of saturated and unsaturated fatty acids, or (b) a biodiesel blend comprising about 2% to about 98% by volume of a biodiesel as described herein and about 2% to about 98% by volume of a petroleum distillate, or in some aspects about 10% to about 90% by volume of a biodiesel and about 10% to about 90% by volume of a petroleum distillate, or in some aspects about 20% to about 80% by volume
  • the fuel compositions comprise: (1) between about 0.1% to about 0.35% by volume of a cetane improver; (2) a biodiesel blend comprising (a) about 5% to about 30% by volume of a biodiesel comprising a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, or a mixture thereof, and (b) about 70 to about 95% by volume of a diesel; and (3) an antioxidant comprising (a) a diphenol selected from the group consisting of tert- butylhydroquinone, 2-tert-butyl- 1 ,4-hydroquinone, 2,5-di-tert-butyl- 1 ,4- hydroquinone, methylhydroquinone, and 2,5-di-tert.-octylhydroquinone, and (b) a sterically hindere
  • the fuel compositions comprise: (1) between about 0.1% to about 0.35% by volume of a cetane improver; (2) a biodiesel blend comprising (a) about 5% to about 15% by volume of a biodiesel comprising a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, or a mixture thereof, and (b) about 85 to about 95% by volume of a diesel; and (3) an antioxidant comprising (a) a diphenol selected from the group consisting of tert- butylhydroquinone, 2-tert-butyl- 1 ,4-hydroquinone, 2,5-di-tert-butyl- 1 ,4- hydroquinone, methylhydroquinone, and 2,5-di-tert.-octylhydroquinone, and (b) a sterically hindere
  • the fuel compositions comprise: (1) between about 0.1% to about 0.35% by volume of a cetane improver; (2) a biodiesel blend comprising (a) about 5% to about 15% by volume of a biodiesel comprising between about 50% to about 99% by weight of methyl, ethyl, and propyl esters of saturated and unsaturated fatty acids, and (b) about 85 to about 95% by volume of a diesel; and (3) an antioxidant comprising (a) a diphenol selected from the group consisting of tert-butylhydroquinone, 2-tert-butyl-l,4- hydroquinone, 2,5-di-tert-butyl-l,4-hydroquinone, methylhydroquinone, and 2,5-di-tert-octylhydroquinone, and (b) a sterically hindered phenol selected from the group consisting of 2, 6-di-tert-butylphenol, 2, 4-
  • the fuel compositions comprise: (1) between about 0.1% to about 0.35% by volume of 2-ethylhexyl nitrate; (2) a biodiesel blend comprising (a) about 5% to about 10% by volume of a biodiesel comprising a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, or a mixture thereof, and (b) about 90% to about 95% by volume of a diesel; and (3) an antioxidant comprising (a) a diphenol selected from the group consisting of tert- butylhydroquinone, 2-tert-butyl- 1 ,4-hydroquinone, 2,5-di-tert-butyl- 1 ,4- hydroquinone, methylhydroquinone, and 2,5-di-tert.-octylhydroquinone, and (b)
  • the fuel compositions comprise: (1) between about 0.1% to about 0.35% by volume of 2-ethylhexyl nitrate; (2) a biodiesel blend comprising (a) about 5% to about 10% by volume of a biodiesel comprising a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, or a mixture thereof, and (b) about 90% to about 95% by volume of a diesel; and (3) a diphenol and a sterically hindered phenol selected, respectively, from a compound of formula (I) and a compound of formula (II):
  • R] and R 3 are H or a tert-butyl group, and R 2 is H, CH 3 , a tert-butyl group or - CH 2 -N(CH 3 ) 2 ;
  • the amount of the antioxidant is between about 100 milligrams per liter biodiesel blend to about 500 milligrams per liter of the biodiesel blend, and wherein (c) the volumetric ratio of the diphenol to the sterically hindered phenol is between about 0.5: 1 to about 1.5:1.
  • the fuel compositions comprise: (1) between about 0.1% to about 0.35% by volume of 2-ethylhexyl nitrate; (2) a biodiesel comprising about a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, or a mixture thereof; and (3) a diphenol and a sterically hindered phenol selected, respectively, from a compound of formula (I) and a compound of formula (II):
  • Ri and R 3 are H or a tert-butyl group, and R 2 is H, CH 3 , a tert-butyl group or - CH 2 -N(CH 3 ) 2 ;
  • the amount of the antioxidant is between about 200 milligrams per liter of the biodiesel blend to about 400 milligrams per liter of the biodiesel blend, and wherein (c) the volumetric ratio of the diphenol to the sterically hindered phenol is between about 0.9: 1 to about 1 : 1.
  • oxidation is induced by passing a stream of purified air at the rate of 10 liters/hr through the biodiesel sample (approx. 7.5 g), kept at constant temperature.
  • the vapors released during the oxidation process, together with the air, are passed into the flask containing 60 ml of water which has been demineralized or distilled and contains an electrode for measuring the
  • the electrode is connected to a measuring and recording device.
  • the end of the induction period is indicated when the conductivity begins to increase rapidly. This accelerated increase in conductivity is caused by the dissociation of volatile carboxylic acids which are produced during the oxidation process and which are absorbed in the water.
  • an oxidation curve is obtained whose point of inflection indicates the induction period; which provides the characteristic value for the oxidation stability.
  • the EN 14214 Standard for the BlOO and ASTM D7467 Standard for the B6-B20 biodiesel fuels specify a Rancimat induction period of six hours minimum.
  • a cetane improver such as 2-ethylhexyl nitrate improves the ignition quality of, and degrades the Rancimat oxidation stability of, a biodiesel blend or a biodiesel.
  • Sterically hindered phenolic antioxidants improved the oxidation stability of the biodiesel or biodiesel blend fuels, but not to the same extent as a diphenol such as tert- butylhydroquinone antioxidant.
  • a combination of a sterically hindered phenolic antioxidant with a diphenol such as tert-butylhydroquinone provided similar, and in some cases even directionally better, oxidation stability when compared to the use of only a diphenol.
  • Fuel 1 5 vol% Soybean Methyl Ester + 95 vol% petroleum diesel fuel
  • Fuel 2 99.7 vol% Fuel 1 + 0.3 vol% 2-ethylhexyl nitrate
  • Fuel 3 Fuel 2 + 400 mg/L Ethanox 4733
  • Fuel 4 Fuel 2 + 400 mg/L Ethanox 4703
  • Fuel 5 Fuel 2 + 400 mg/L 2-tert-butyl- 1 ,4-hydroquinone
  • Fuel 6 Fuel 2 + 200 mg/L Ethanox 4703 + 200mg/L 2-tert-butyl- 1, 4- hydroquinone
  • Fuel 7 Fuel 2 + 200 mg/L Ethanox 4733 + 200 mg/L 2-tert-butyl- 1 , 4- hydroquinone
  • Fuel 8 Fuel 6 calculated Rancimat stability
  • Fuel 9 Fuel 7 calculated Rancimat stability Example 3
  • Fuel 1 5 vol% Soybean Methyl Ester + 95 vol% petroleum diesel fuel
  • Fuel 2 99.7 vol% Fuel 1 + 0.3 vol% 2-ethylhexyl nitrate
  • Fuel 3 Fuel 2 + 400 mg/L Ethanox 4733
  • Fuel 4 Fuel 2 + 400 mg/L Ethanox 4703
  • Fuel 5 Fuel 2 + 400 mg/L 2-tert-butyl-l, 4-hydroquinone
  • Fuel 6 Fuel 2 + 200 mg/L Ethanox 4703 + 200mg/L 2-tert-butyl-l, 4- hydroquinone
  • Fuel 7 Fuel 2 + 200 mg/L Ethanox 4733 + 200 mg/L 2-tert-butyl-l, 4- hydroquinone
  • Fuel 2 99.7 vol% Fuel 1 + 0.3 vol% 2-ethylhexyl nitrate Fuel 3 : Fuel 2 + 400 mg/L Ethanox 4733
  • Fuel 4 Fuel 2 + 400 mg/L Ethanox 4703
  • Fuel 10 Fuel 2 + 400 mg/L 2,6-di-tert-butylbenzoquinone
  • Fuel 11 Fuel 2 + 200 mg/L Ethanox 4733 + 200 mg/L 2,6-di-tert- butylbenzoquinone
  • Fuel 12 Fuel 2 + 200 mg/L Ethanox 4703 + 200 mg/L 2,6-di-tert- butylbenzoquinone
  • Fuels 2, 3, 4, 10, 11, and 12 were comprised of Fuels 1 or 2 (Example 1).

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Abstract

biodiesel, diesel, blend, cetane improver, antioxidant, dihydroxybenzene, 2,6-di-tert-butyl-alpha-dimethylamιno-p-cresol, 2-ethylhexyl nitrate, cyclohexyl nitrate, di-tert-butyl peroxide, methyl nitrate, ethyl nitrate, n-propyl nitrate, isopropyl nitrate, allyl nitrate, n-butyl nitrate, isobutyt nitrate, sec-butyl nitrate, tert-butyl nitrate, n-amyl nitrate, isoamyl nitrate, 2-amyl nitrate, 3-amyl nitrate, tert-amyl nitrate, n-hexyl nitrate, 2-ethylhexyl nitrate, n-heptyl nitrate, sec-heptyl nitrate, n-octyl nitrate, sec-octyl nitrate, n-nonyl nitrate, n-decyl nitrate, n-dodecyl nitrate, cyclopentylnitrate, cyclohexylnitrate, methylcyclohexyl nitrate, isopropylcyclohexyl nitrate, 1 -methoxypropyl-2-nιtrate, 1 - ethoxpropyl-2 nitrate, 1 -isopropoxy-butyl nitrate, 1-ethoxylbutyl nitrate, nitrate, diphenol, hydroqumone, tert-butylhydroqumone, 2-tert- butyl-1,4-hydroquιnone, 2,5-ditert-butyl-1,4-hydroquιnone, methylhydroquinone, 2,5-di-tert octylhydroquinone, benzenediol, dihydroxybenzene, Resorcinol, Pyrocatechol, sterically hindered phenol, "2,6-di-tert-butylphenol", "2,4-di-tert-butylphenor, 6-dι-tert- butyl-4-methylphenol, 2-tert-butylphenol, 2,4,6-tri-tert-butylphenol, 2,6-di-tertbutyl-4-dιmethylamιnomethylphenol, ethanox

Description

BIODIESEL AND BIODIESEL BLEND FUELS
FIELD OF THE INVENTION
[001] The invention provides fuel compositions comprising synergistic combinations of a biodiesel or biodiesel blend, an antioxidant comprising a mixture of at least one diphenol and at least one sterically hindered phenol, and a cetane improver.
BACKGROUND OF THE INVENTION
[002] Biodiesel is the name for a variety of ester-based oxygenated fuels made from vegetable oils, fats, greases, or other sources of triglycerides.
Biodiesel is a nontoxic and biodegradable blendstock which may be blended with petroleum diesel provided relevant specifications are met. Blends of biodiesel with petroleum diesel can substantially reduce the emission levels and toxicity of diesel exhaust. Biodiesel has been designated as an alternative fuel by the United States Department of Energy and the United States Department of Transportation, and is registered with the United States Environmental
Protection Agency as a fuel and fuel additive.
[003] Biodiesel fuels typically contain unsaturated fatty acid esters that can easily oxidize in the presence of oxygen, especially if UV light, and/or trace metals are also present. The products formed from this oxidation give rise to sediment and gum formation within the fuel that can lead to corrosion and plugging of filters, pumps and fuel injectors which utilize fuel containing biodiesel.
[004] While antioxidants such as sterically-hindered phenols have been used in an effort to stabilize biodiesels, there remains a need for a biodiesel composition that has both improved oxidation stability and ignition quality that reduces or eliminates gum formation within the fuel, and that reduces or eliminates corrosion and plugging of filters, vehicular injection pumps and fuel injectors.
SUMMARY OF THE INVENTION
[005] We have discovered fuel compositions comprising synergistic combinations of a biodiesel (BlOO) or biodiesel blend (Bx), an antioxidant comprising a mixture of at least one diphenol and at least one sterically hindered phenol, and a cetane improver. Notably, the fuel compositions described herein evidence enhanced oxidation stability as determined by the Rancimat test method (prEN 15751), even though they contain an ignition-enhancing, oxidation stability-degrading cetane improver.
[006] In one aspect, the fuel compositions comprise: (1) between about 0.01% to about 1% by volume of a cetane improver; (2) either (a) a biodiesel, or (b) a biodiesel blend comprising about 2% to about 98% by volume of a biodiesel and about 2% to about 98% by volume of a petroleum distillate; and (3) an antioxidant comprising a mixture of at least one diphenol and at least one sterically hindered phenol, wherein (a) the amount of the antioxidant is (i) between about 20 milligrams per kilogram of the biodiesel or biodiesel blend to about 10,000 milligrams per kilogram of the biodiesel or biodiesel blend, or (ii) is between about 16 milligrams per liter of the biodiesel or biodiesel blend to about 8,000 milligrams per liter of the biodiesel or biodiesel blend, and (b) wherein the volumetric ratio of the diphenol(s) to the sterically hindered phenol(s) is between about 0.01 : 1 to about 10: 1.
[007] Given their unique combination of improved oxidation stability, enhanced ignition quality and the fact that an antioxidant combination of a sterically hindered phenol and diphenol is cheaper than a pure diphenol antioxidant, the fuel compositions described herein facilitate a wider use of biodiesels and biodiesel blends. Further, the fuel compositions described herein should avoid the corrosion, plugging, and sediment and gum formation associated with known biodiesels and biodiesel blends.
[008] These and other aspects of the invention are described further in the following detailed description of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[009] FIGURE 1 and FIGURE 2 illustrate that the addition of a cetane improver to biodiesel fuels reduced their oxidation stability measured by the Rancimat test method (prEN 15751), as determined in the experiment of
Example 1. As described in Examples 1-4 hereinafter, the fuels tested were Fuel 1 (5% by volume of soybean methyl ester plus 95% by volume of petroleum diesel fuel), Fuel 2 (99.7% by volume of Fuel 1 + 0.3% by volume of 2- ethylhexyl nitrate), and variants of Fuel 2.
[010] FIGURE 3 illustrates the oxidation-stabilizing effect of adding a diphenol and a sterically hindered phenol to biodiesel fuels containing a cetane improver, as determined in the experiment of Example 2.
[011] FIGURE 4 illustrates that the presence of a diphenol and a sterically hindered phenol did not significantly affect the ignition quality of biodiesel fuels containing a cetane improver, as determined in the experiment of Example 3.
[012] FIGURE 5 illustrates that a benzoquinone proved ineffective as an oxidation-stabilizing substitute for a diphenol, as determined in the experiment of Example 4.
DETAILED DESCRIPTION OF THE INVENTION
[013] Unless otherwise stated, all percentages disclosed herein are on a volume basis.
[014] Any end point of a range stated herein can be combined with any other end point to form another suitable range. [015] The following definitions apply unless indicated otherwise.
[016] "Biodiesel" means a composition that can be used as a fuel for diesel engines and that contains at least about 50% by weight of esters of saturated and unsaturated fatty acids, including fatty acid methyl esters (FAME's), fatty acid ethyl esters (FAEE' s), propyl esters of fatty acids, or combinations of two or more methyl, ethyl, and propyl esters. In one example, a biodiesel comprises between about 50% to about 99% by weight of methyl esters of saturated and unsaturated fatty acids, where the methyl esters of saturated and unsaturated fatty acids include C8-C24 fatty acid methyl esters, where C8-C24 indicates the number of carbons in the original fatty acid.
[017] Biodiesels can be made by transesterification of one or more vegetable oils, animal fats, or mixtures thereof (e.g. soybean oil, rapeseed oil, palm oil, canola oil, sunflower oil, olive oil, corn oil, tallow oil, coconut oil, jatropha oil, yellow grease, animal fats, used cooking oil, and mixtures thereof) with an alcohol such as methanol or ethanol. In one aspect the fatty acid esters are largely unsaturated and comprise a rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, or a mixture thereof. A 100% biodiesel (B lOO) should meet ASTM D6751 and/or EN 14214 specifications.
[018] Biodiesel blends (biodiesel blended with a petroleum distillate such as diesel fuel)(Bx) have a composition reflective of blend ratio and the distillate chosen for the blend.
[019] "Petroleum distillate" includes naphtha or middle distillates including kerosene and diesel.
[020] A non-limiting example of a "diesel fuel" or "a diesel" is composed of a mixture Of C9-C24 hydrocarbons that comprise about 50% to about 95% by volume of aliphatic hydrocarbons, of which about 0% to about 50% by volume are cycloparaffins, about 0% to about 5% by volume of olefinic hydrocarbons, and about 5% to about 50% by volume of aromatic hydrocarbons, and which boil at between about 2800F (138°C) and 75O0F (3990C).
[021] A non-limiting example of a "kerosene" comprises about 5% to about 50% by volume of an aromatic fraction, about 0% to about 50% by volume of a cycloparaffin fraction, and about 0% to about 5% by volume of an olefinic fraction, with the rest comprising aliphatic hydrocarbons.
[022] An aromatics fraction can contain methyl aromatics and non-methyl alkyl aromatics. Non-limiting examples of non-methyl alkyl aromatics include molecules such as,alkyl benzenes, dialkylbenzenes, alkylnaphthalenes, alkyl biphenyls, and alkyl phenanthrenes, and the like, in which one or more linear or branched alkyl groups containing two or more carbons is bonded to the aromatic ring. Non-limiting examples of methyl aromatics include aromatic molecules such as methylnaphthalene, dimethylnaphthalenes, and the like.
[023] A cycloparaffin fraction consists of cycloalkanes or molecules containing at least one cycloalkane ring. Non-limiting examples of components of the cycloparaffin fraction include alkylcyclohexanes and alkylcyclopentanes.
[024] An olefinic fraction can contain linear, branched, and cyclo-olefins. Non-limiting examples of components of the olefinic fraction include dodecenes and hexadecenes.
[025] A "cetane improver" includes but is not limited to 2-ethylhexyl nitrate (EHN) (e.g. HITEC® 4103, Ethyl Corp., Richmond, VA), cyclohexyl nitrate, di- tert-butyl peroxide, methyl nitrate, ethyl nitrate, n-propyl nitrate, isopropyl nitrate, allyl nitrate, n-butyl nitrate, isobutyl nitrate, sec-butyl nitrate, tert-butyl nitrate, n-amyl nitrate, isoamyl nitrate, 2-amyl nitrate, 3-amyl nitrate, tert-amyl nitrate, n-hexyl nitrate, 2-ethylhexyl nitrate, n-heptyl nitrate, sec-heptyl nitrate, n-octyl nitrate, sec-octyl nitrate, n-nonyl nitrate, n-decyl nitrate, n-dodecyl nitrate, cyclopentylnitrate, cyclohexylnitrate, methylcyclohexyl nitrate, isopropylcyclohexyl nitrate, and the esters of alkoxy substituted aliphatic alcohols, such as l-methoxypropyl-2-nitrate, l-ethoxpropyl-2 nitrate, 1- isopropoxy-butyl nitrate, 1-ethoxylbutyl nitrate, and mixtures thereof.
[026] A "diphenol" includes but is not limited to hydroquinone (HQ), mono and dialkylated hydroquinones having one or two C1-C8 alkyl groups (e.g. tert- butylhydroquinone (TBHQ), 2-tert-butyl- 1 ,4-hydroquinone, 2,5-di-tert-butyl- 1,4-hydroquinone, methylhydroquinone (toluhydroquinone or THQ), 2,5-di-tert.- octylhydroquinone (DOH)), and mixtures thereof.
[027] A "sterically hindered phenol" includes but is not limited to mono, di, and trialkylated phenols such as 2, 6-di-tert-butylphenol, 2, 4-di-tert- butylphenol, 2, 6-di-tert-butyl-4-methylphenol (BHT), 2-tert-butylphenol, 2, 4, 6-tri-tert-butylphenol, 2, 6-di-tert-butyl-4-dimethylaminomethylphenol, and mixtures thereof. Commercially-available sterically hindered phenols that can be used in the fuel compositions described herein include Ethanox® 4703 and 4733 (Albermarle Corp., Baton Rouge, LA), Westco® AO-29 (Western Reserve Chemical, Stow, OH), Baynox® (Lanxess, Leverkusen, DE), and Ionol® BF 150 and BF 200 (Oxiris Chemicals S. A.., Barcelona, ES).
[028] In certain aspects, the diphenol and sterically hindered phenol are selected, respectively, from a compound of formula (I) and a compound of formula (II):
wherein R1 and R3 are H or a tert-butyl group and R2 is H, CH3, a tert-butyl group or -CH2-N(CH3)2. [029] In one aspect, fuel compositions of the invention may also include an aromatic amine antioxidant (e.g. a phenylediamine- type antioxidant) such as N, N'-di-sec-butyl-p-phenylenediamine, 4-isopropylaminodiphenylamine, phenyl- naphthyl amine, and ring-alkylated diphenylamines.
[030] Fuel compositions of the invention may also include performance additives such as cold flow additives, cloud point depressants, biocides, conductivity improvers, corrosion inhibitors, metal deactivators, and engine cleaning agents. In some aspects, such additives are present in an amount which ranges from about 0.001 to about 2.0% by weight of the fuel composition.
[031] In certain aspects, the fuel compositions comprise: (1) between about 0.01% to about 1%, in some aspects between about 0.01% to about 0.75%, in some aspects between 0.01% to about 0.5%, and in some aspects between about 0.01% to about 0.35% by volume of a cetane improver; (2) either (a) a biodiesel comprising at least about 50% by weight, in some aspects at least about 60% by weight, in some aspects at least about 70% by weight, in some aspects at least about 80% by weight, in some aspects at least about 90% by weight, in some aspects at least about 95% by weight of esters of saturated and unsaturated fatty acids, or (b) a biodiesel blend comprising about 2% to about 98% by volume of a biodiesel as described herein and about 2% to about 98% by volume of a petroleum distillate, or in some aspects about 10% to about 90% by volume of a biodiesel and about 10% to about 90% by volume of a petroleum distillate, or in some aspects about 20% to about 80% by volume of a biodiesel and about 20% to about 80% by volume of a petroleum distillate, or in some aspects about 30% to about 70% by volume of a biodiesel and about 30% to about 70% by volume of a petroleum distillate, or in some aspects about 40% to about 60% by volume of a biodiesel and about 40% to about 60% by volume of a petroleum distillate, or in some aspects about 50% by volume of a biodiesel and about 50% by volume of a petroleum distillate, or in some aspects about 30% by volume of a biodiesel and about 70% by volume of a petroleum distillate, or in some aspects about 20% by volume of a biodiesel and about 80% by volume of a petroleum distillate, or in some aspects about 5-10% by volume of a biodiesel and about 90-95% by volume of a petroleum distillate; and (3) an antioxidant comprising a mixture of at least one diphenol and at least one sterically hindered phenol, wherein (a) the amount of the antioxidant is (i) between about 20 milligrams per kilogram of the biodiesel or biodiesel blend to about 10,000 milligrams per kilogram of the biodiesel or biodiesel blend, or in some aspects is between about 100 milligrams per kilogram of the biodiesel or biodiesel blend to about 5,000 milligrams per kilogram of the biodiesel or biodiesel blend, or in some aspects is between about 100 milligrams per kilogram of the biodiesel or biodiesel blend to about 1,000 milligrams per kilogram of the biodiesel or biodiesel blend, or in some aspects is between about 100 milligrams per kilogram of the biodiesel or biodiesel blend to about 500 milligrams per kilogram of the biodiesel or biodiesel blend, or (ii) in some aspects is between about 16 milligrams per liter of the biodiesel or biodiesel blend to about 8,000 milligrams per liter of the biodiesel or biodiesel blend, or in some aspects is between about 100 or about 200 milligrams per liter of the biodiesel or biodiesel blend to about 400 or about 500 milligrams per liter of the biodiesel or biodiesel blend, and wherein (b) the volumetric ratio of the diphenol(s) to the sterically hindered phenol(s) is between about 0.01 : 1 to about 10: 1 , or in some aspects is about 0.1 : 1 , or in some aspects is about 0.25:1, or in some aspects is about 0.5:1, or in some aspects is about 0.75:1, or in some aspects is about 0.9: 1, or in some aspects is about 1: 1, or in some aspects is about 1.25:1, or in some aspects is about 1.5:1.
[032] In some aspects, the fuel compositions comprise: (1) between about 0.1% to about 0.35% by volume of a cetane improver; (2) a biodiesel blend comprising (a) about 5% to about 30% by volume of a biodiesel comprising a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, or a mixture thereof, and (b) about 70 to about 95% by volume of a diesel; and (3) an antioxidant comprising (a) a diphenol selected from the group consisting of tert- butylhydroquinone, 2-tert-butyl- 1 ,4-hydroquinone, 2,5-di-tert-butyl- 1 ,4- hydroquinone, methylhydroquinone, and 2,5-di-tert.-octylhydroquinone, and (b) a sterically hindered phenol selected from the group consisting of 2, 6-di-tert- butylphenol, 2, 4-di-tert-butylphenol, 2, 6-di-tert-butyl-4-methylphenol, 2-tert- butylphenol, 2, 4, 6-tri-tert-butylphenol, and 2, 6-di-tert-butyl-4- dimethylaminomethylphenol, wherein (a) the amount of the antioxidant is between about 100 milligrams per liter biodiesel blend to about 500 milligrams per liter of the biodiesel blend, and wherein (b) the volumetric ratio of the diphenol to the sterically hindered phenol is between about 0.5:1 to about 1.5:1.
[033] In some aspects, the fuel compositions comprise: (1) between about 0.1% to about 0.35% by volume of a cetane improver; (2) a biodiesel blend comprising (a) about 5% to about 15% by volume of a biodiesel comprising a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, or a mixture thereof, and (b) about 85 to about 95% by volume of a diesel; and (3) an antioxidant comprising (a) a diphenol selected from the group consisting of tert- butylhydroquinone, 2-tert-butyl- 1 ,4-hydroquinone, 2,5-di-tert-butyl- 1 ,4- hydroquinone, methylhydroquinone, and 2,5-di-tert.-octylhydroquinone, and (b) a sterically hindered phenol selected from the group consisting of 2, 6-di-tert- butylphenol, 2, 4-di-tert-butylphenol, 2, 6-di-tert-butyl-4-methylphenol, 2-tert- butylphenol, 2, 4, 6-tri-tert-butylρhenol, and 2, 6-di-tert-butyl-4- dimethylaminomethylphenol, wherein (a) the amount of the antioxidant is between about 200 milligrams per liter of the biodiesel blend to about 400 milligrams per liter of the biodiesel blend, and wherein (b) the volumetric ratio of the diphenol to the sterically hindered phenol is between about 0.75: 1 to about 1 :1.
[034] In some aspects, the fuel compositions comprise: (1) between about 0.1% to about 0.35% by volume of a cetane improver; (2) a biodiesel blend comprising (a) about 5% to about 15% by volume of a biodiesel comprising between about 50% to about 99% by weight of methyl, ethyl, and propyl esters of saturated and unsaturated fatty acids, and (b) about 85 to about 95% by volume of a diesel; and (3) an antioxidant comprising (a) a diphenol selected from the group consisting of tert-butylhydroquinone, 2-tert-butyl-l,4- hydroquinone, 2,5-di-tert-butyl-l,4-hydroquinone, methylhydroquinone, and 2,5-di-tert-octylhydroquinone, and (b) a sterically hindered phenol selected from the group consisting of 2, 6-di-tert-butylphenol, 2, 4-di-tert-butylphenol, 2, 6-di-tert-butyl-4-methylphenol, 2-tert-butylphenol, 2, 4, 6-tri-tert-butylphenol, and 2, 6-di-tert-butyl-4-dimethylaminomethylphenol, wherein (a) the amount of the antioxidant is between about 200 milligrams per liter of the biodiesel blend to about 400 milligrams per liter of the biodiesel blend, and wherein (b) the volumetric ratio of the diphenol to the sterically hindered phenol is between about 0.75: 1 to about 1 :1.
[035] In some aspects, the fuel compositions comprise: (1) between about 0.1% to about 0.35% by volume of 2-ethylhexyl nitrate; (2) a biodiesel blend comprising (a) about 5% to about 10% by volume of a biodiesel comprising a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, or a mixture thereof, and (b) about 90% to about 95% by volume of a diesel; and (3) an antioxidant comprising (a) a diphenol selected from the group consisting of tert- butylhydroquinone, 2-tert-butyl- 1 ,4-hydroquinone, 2,5-di-tert-butyl- 1 ,4- hydroquinone, methylhydroquinone, and 2,5-di-tert.-octylhydroquinone, and (b) a sterically hindered phenol selected from the group consisting of 2, 6-di-tert- butylphenol, 2, 4-di-tert-butylphenol, 2, 6-di-tert-butyl-4-methylphenol, 2-tert- butylphenol, 2, 4, 6-tri-tert-butylphenol, and 2, 6-di-tert-butyl-4- dimethylaminomethylphenol, wherein (a) the amount of the antioxidant is between about 200 milligrams per liter of the biodiesel blend to about 400 milligrams per liter of the biodiesel blend, and wherein (b) the volumetric ratio of the diphenol to the sterically hindered phenol is between about 0.9: 1 to about
1 :1.
[036] In some aspects, the fuel compositions comprise: (1) between about 0.1% to about 0.35% by volume of 2-ethylhexyl nitrate; (2) a biodiesel blend comprising (a) about 5% to about 10% by volume of a biodiesel comprising a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, or a mixture thereof, and (b) about 90% to about 95% by volume of a diesel; and (3) a diphenol and a sterically hindered phenol selected, respectively, from a compound of formula (I) and a compound of formula (II):
< Il wherein:
(a) R] and R3 are H or a tert-butyl group, and R2 is H, CH3, a tert-butyl group or - CH2-N(CH3)2; (b) the amount of the antioxidant is between about 100 milligrams per liter biodiesel blend to about 500 milligrams per liter of the biodiesel blend, and wherein (c) the volumetric ratio of the diphenol to the sterically hindered phenol is between about 0.5: 1 to about 1.5:1.
[037] In some aspects, the fuel compositions comprise: (1) between about 0.1% to about 0.35% by volume of 2-ethylhexyl nitrate; (2) a biodiesel comprising about a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, or a mixture thereof; and (3) a diphenol and a sterically hindered phenol selected, respectively, from a compound of formula (I) and a compound of formula (II):
wherein
(a) Ri and R3 are H or a tert-butyl group, and R2 is H, CH3, a tert-butyl group or - CH2-N(CH3)2; (b) the amount of the antioxidant is between about 200 milligrams per liter of the biodiesel blend to about 400 milligrams per liter of the biodiesel blend, and wherein (c) the volumetric ratio of the diphenol to the sterically hindered phenol is between about 0.9: 1 to about 1 : 1.
[038] These and other aspects of the fuel compositions described herein are illustrated further in the following examples, which are illustrative and are not limiting.
Experimental Apparatus and Methods
[039] The following experimental apparatus and methods were used in the experiments of Examples 1-4 described below.
[040] Experiments were undertaken in accord with the Rancimat test method (prEN 15751). The Rancimat test is carried out by passing a steady stream of air through a heated (1 100C) sample and measuring the volatile oxidation species produced over a period of time. The point at which the rate of production of the volatile oxidation species reaches a maximum is defined as the induction period or oxidation stability (measured in hours at the given temperature) and provides a characteristic value for oxidation stability.
[041] Specifically, oxidation is induced by passing a stream of purified air at the rate of 10 liters/hr through the biodiesel sample (approx. 7.5 g), kept at constant temperature. The vapors released during the oxidation process, together with the air, are passed into the flask containing 60 ml of water which has been demineralized or distilled and contains an electrode for measuring the
conductivity. The electrode is connected to a measuring and recording device. The end of the induction period is indicated when the conductivity begins to increase rapidly. This accelerated increase in conductivity is caused by the dissociation of volatile carboxylic acids which are produced during the oxidation process and which are absorbed in the water. When the conductivity of this measuring solution is recorded continuously, an oxidation curve is obtained whose point of inflection indicates the induction period; which provides the characteristic value for the oxidation stability. The EN 14214 Standard for the BlOO and ASTM D7467 Standard for the B6-B20 biodiesel fuels specify a Rancimat induction period of six hours minimum.
Example 1
[042] We unexpectedly found that the presence of a cetane improver such as 2-ethylhexyl nitrate improves the ignition quality of, and degrades the Rancimat oxidation stability of, a biodiesel blend or a biodiesel. Sterically hindered phenolic antioxidants improved the oxidation stability of the biodiesel or biodiesel blend fuels, but not to the same extent as a diphenol such as tert- butylhydroquinone antioxidant. However, a combination of a sterically hindered phenolic antioxidant with a diphenol such as tert-butylhydroquinone provided similar, and in some cases even directionally better, oxidation stability when compared to the use of only a diphenol.
[043] The experiment of this example shows that the addition of a 2- ethylhexyl nitrate cetane improver to a biodiesel fuel reduced its Rancimat (prEN 15751) oxidation stability by about 26.5% (average of 2 Rancimat stability results). As listed below and as depicted in Figures 1 and 2, upon addition of the cetane improver, oxidation stability decreased for each of the fuels tested. Figure 1
Fuel 1 : 5 vol% Soybean Methyl Ester + 95 vol% petroleum diesel fuel
Fuel 2: 99.7 vol% Fuel 1 + 0.3 vol% 2-ethylhexyl nitrate
Comparative Examples (Figure 2)
B5 SME (no EHN) 28.4 hours
B5 SME + 0.1 vol% EHN 23.7 hours (16.6% Rancimat stability redution) B5 SME + 0.2 vol% EHN 20.4 hours (28.2% Rancimat stability reduction) B5 SME + 0.35 vol% EHN 10.3 hours (63.7% Rancimat stability reduction)
Example 2
[044] The experiment of this example shows that sterically hindered phenolic antioxidants improve the Rancimat stability of biodiesel fuel containing a cetane improver, but not to the same extent as a diphenol such as 2-tert- butylhydroquinone. However, as seen in Figure 3, a mixture of a 50% by volume 2-tert-butylhydroquinone with 50% by volume of sterically hindered phenols provided significantly better Rancimat stability than the calculated Rancimat stability for that composition.
Figure 3
Fuel 3: Fuel 2 + 400 mg/L Ethanox 4733
Fuel 4: Fuel 2 + 400 mg/L Ethanox 4703
Fuel 5: Fuel 2 + 400 mg/L 2-tert-butyl- 1 ,4-hydroquinone
Fuel 6: Fuel 2 + 200 mg/L Ethanox 4703 + 200mg/L 2-tert-butyl- 1, 4- hydroquinone
Fuel 7: Fuel 2 + 200 mg/L Ethanox 4733 + 200 mg/L 2-tert-butyl- 1 , 4- hydroquinone
Fuel 8: Fuel 6 calculated Rancimat stability
Fuel 9: Fuel 7 calculated Rancimat stability Example 3
[045] The experiment of this example shows (as depicted in Figure 4) that the 2-ethylhexyl nitrate cetane improver increases the ASTM D6890 ignition quality of the biodiesel Fuels 1-7 and that the presence of antioxidants did not significantly affect the ignition quality of the biodiesel fuels. Fuels 1-7 were comprised of Fuels 1 or 2 (Example 1).
Figure 4
Fuel 1: 5 vol% Soybean Methyl Ester + 95 vol% petroleum diesel fuel
Fuel 2: 99.7 vol% Fuel 1 + 0.3 vol% 2-ethylhexyl nitrate
Fuel 3 : Fuel 2 + 400 mg/L Ethanox 4733
Fuel 4: Fuel 2 + 400 mg/L Ethanox 4703
Fuel 5: Fuel 2 + 400 mg/L 2-tert-butyl-l, 4-hydroquinone
Fuel 6: Fuel 2 + 200 mg/L Ethanox 4703 + 200mg/L 2-tert-butyl-l, 4- hydroquinone
Fuel 7: Fuel 2 + 200 mg/L Ethanox 4733 + 200 mg/L 2-tert-butyl-l, 4- hydroquinone
Example 4
[046] The experiment of this example shows (as depicted in Figure 5) that compared to a diphenol such as tert-butylhydroquinone, a benzoquinone such as 2,6-di-tert-butyl [1, 4] benzoquinone (formula (III)) proves ineffective as an antioxidant..
Figure 5
Fuel 2: 99.7 vol% Fuel 1 + 0.3 vol% 2-ethylhexyl nitrate Fuel 3 : Fuel 2 + 400 mg/L Ethanox 4733
Fuel 4: Fuel 2 + 400 mg/L Ethanox 4703
Fuel 10: Fuel 2 + 400 mg/L 2,6-di-tert-butylbenzoquinone
Fuel 11 : Fuel 2 + 200 mg/L Ethanox 4733 + 200 mg/L 2,6-di-tert- butylbenzoquinone
Fuel 12: Fuel 2 + 200 mg/L Ethanox 4703 + 200 mg/L 2,6-di-tert- butylbenzoquinone
Fuels 2, 3, 4, 10, 11, and 12 were comprised of Fuels 1 or 2 (Example 1).
[047] It is to be understood that the above description is intended for illustrative purposes only and is not intended to limit the scope of the present invention in any way.

Claims

CLAIMS:
1. A fuel composition comprising:
(a) between about 0.01% to about 1% by volume of a cetane improver;
(b) a biodiesel blend comprising about 2% to about 98% by volume of a biodiesel and about 2% to about 98% by volume of a petroleum distillate; and
(c) an antioxidant comprising a mixture of a diphenol and a sterically hindered phenol, wherein
(1) the amount of the antioxidant is (i) between about 20 milligrams per kilogram to about 10,000 milligrams per kilogram of the biodiesel blend, or (ii) is between about 16 milligrams per liter to about 8,000 milligrams per liter of the biodiesel blend, and
(2) wherein the volumetric ratio of the diphenol to the sterically hindered phenol is between about 0.01: 1 to about 10:1.
2. The fuel composition of claim 1, wherein:
(a) the cetane improver is selected from the group consisting of 2-ethylhexyl nitrate, cyclohexyl nitrate, di-tert-butyl peroxide, methyl nitrate, ethyl nitrate, n-propyl nitrate, isopropyl nitrate, allyl nitrate, n-butyl nitrate, isobutyl nitrate, sec-butyl nitrate, tert-butyl nitrate, n-amyl nitrate, isoamyl nitrate, 2-amyl nitrate, 3-amyl nitrate, tert-amyl nitrate, n-hexyl nitrate, 2- ethylhexyl nitrate, n-heptyl nitrate, sec-heptyl nitrate, n-octyl nitrate, sec-octyl nitrate, n-nonyl nitrate, n-decyl nitrate, n-dodecyl nitrate, cyclopentylnitrate, cyclohexylnitrate, methylcyclohexyl nitrate, isopropylcyclohexyl nitrate, l-methoxypropyl-2-nitrate, l-ethoxpropyl-2 nitrate, 1-isopropoxy-butyl nitrate, 1-ethoxylbutyl nitrate, and mixtures thereof; (b) the biodiesel blend comprises (1) between about 2% to about 98% by volume of a biodiesel comprising between about 50% to about 99% by weight of methyl, ethyl, and propyl esters of saturated and unsaturated fatty acids, and (2) between about 2% to about 98% by volume of a petroleum distillate;
(c) the diphenol is selected from the group consisting of hydroquinone, tert-butylhydroquinone, 2-tert-butyl-l,4-hydroquinone, 2,5-di- tert-butyl-l,4-hydroquinone, methylhydroquinone, 2,5-di-tert- octylhydroquinone, and mixtures thereof; and
(d) the sterically hindered phenol is selected from the group consisting of 2, 6-di-tert-butylphenol, 2, 4-di-tert-butylphenol, 2, 6-di-tert-butyl- 4-methylphenol, 2-tert-butylphenol, 2, 4, 6-tri-tert-butylphenol, 2, 6-di-tert- butyl-4-dimethylaminomethylphenol, and mixtures thereof.
3. The fuel composition of claim 1, wherein:
(a) the cetane improver is selected from the group consisting of 2-ethylhexyl nitrate, cyclohexyl nitrate, di-tert-butyl peroxide, methyl nitrate, ethyl nitrate, n-propyl nitrate, isopropyl nitrate, allyl nitrate, n-butyl nitrate, isobutyl nitrate, sec-butyl nitrate, tert-butyl nitrate, n-amyl nitrate, isoamyl nitrate, 2-amyl nitrate, 3-amyl nitrate, tert-amyl nitrate, n-hexyl nitrate, 2- ethylhexyl nitrate, n-heptyl nitrate, sec-heptyl nitrate, n-octyl nitrate, sec-octyl nitrate, n-nonyl nitrate, n-decyl nitrate, n-dodecyl nitrate, eye lop entyl nitrate, cyclohexylnitrate, methylcyclohexyl nitrate, isopropylcyclohexyl nitrate, l-methoxypropyl-2-nitrate, l-ethoxpropyl-2 nitrate, 1-isopropoxy-butyl nitrate, 1-ethoxylbutyl nitrate and mixtures thereof;
(b) the biodiesel blend comprises (1) between about 2% to about 98% by volume of a biodiesel formed by transesterifying an alcohol with a composition selected from the group consisting of soybean oil, rapeseed oil, palm oil, canola oil, sunflower oil, olive oil, corn oil, coconut oil, jatropha oil, tallow oil, yellow grease animal fats, used cooking oil, and mixtures thereof, and (2) between about 2% to about 98% of a petroleum distillate;
(c) the diphenol is selected from the group consisting of hydroquinone, tert-butylhydroquinone, 2-tert-butyl-l,4-hydroquinone, 2,5-di- tert-buty 1- 1 ,4-hydroquinone, methylhydroquinone, 2,5-di-tert- octylhydroquinone and mixtures thereof; and
(d) the sterically hindered phenol is selected from the group consisting of 2, 6-di-tert-butylphenol, 2, 4-di-tert-butylphenol, 2, 6-di-tert-butyl- 4-methylphenol, 2-tert-butylphenol, 2, 4, 6-tri-tert-butylphenol, 2, 6-di-tert- butyl-4-dimethylaminomethylphenol, and mixtures thereof.
4. The fuel composition of claim I5 wherein:
(a) the cetane improver is selected from the group consisting of 2-ethylhexyl nitrate, cyclohexyl nitrate, di-tert-butyl peroxide, methyl nitrate, ethyl nitrate, n-propyl nitrate, isopropyl nitrate, allyl nitrate, n-butyl nitrate, isobutyl nitrate, sec-butyl nitrate, tert-butyl nitrate, n-amyl nitrate, isoamyl nitrate, 2-amyl nitrate, 3-amyl nitrate, tert-amyl nitrate, n-hexyl nitrate, 2- ethylhexyl nitrate, n-heptyl nitrate, sec-heptyl nitrate, n-octyl nitrate, sec-octyl nitrate, n-nonyl nitrate, n-decyl nitrate, n-dodecyl nitrate, cyclopentylnitrate, cyclohexylnitrate, methylcyclohexyl nitrate, isopropyl cyclohexyl nitrate, l-methoxypropyl-2-nitrate, l-ethoxpropyl-2 nitrate, 1-isopropoxy-butyl nitrate, 1-ethoxylbutyl nitrate and mixtures thereof;
(b) the biodiesel blend comprises (1) between about 2% to about 98% by volume of a biodiesel comprising a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, or a mixture thereof, and (2) between about 2% to about 98% by volume of a diesel; (c) the diphenol is selected from the group consisting of hydroquinone, tert-butylhydroquinone, 2-tert-butyl-l,4-hydroquinone, 2,5-di- tert-butyl-l ,4-hydroquinone, methylhydroquinone, 2,5-di-tert- octylhydroquinone, and mixtures thereof; and
(d) the sterically hindered phenol is selected from the group consisting of 2, 6-di-tert-butylphenol, 2, 4-di-tert-butylphenol, 2, 6-di-tert-butyl- 4-methylphenol, 2-tert-butylphenol, 2, 4, 6-tri-tert-butylphenol, 2, 6-di-tert- butyl-4-dimethylaminomethylphenol, and mixtures thereof.
5. The fuel composition of claim I5 wherein:
(a) the cetane improver is selected from the group consisting of 2-ethylhexyl nitrate, cyclohexyl nitrate, di-tert-butyl peroxide, methyl nitrate, ethyl nitrate, n-propyl nitrate, isopropyl nitrate, allyl nitrate, n-butyl nitrate, isobutyl nitrate, sec-butyl nitrate, tert-butyl nitrate, n-amyl nitrate, isoamyl nitrate, 2-amyl nitrate, 3-amyl nitrate, tert-amyl nitrate, n-hexyl nitrate, 2- ethylhexyl nitrate, n-heptyl nitrate, sec-heptyl nitrate, n-octyl nitrate, sec-octyl nitrate, n-nonyl nitrate, n-decyl nitrate, n-dodecyl nitrate, cyclopentylnitrate, cyclohexylnitrate, methylcyclohexyl nitrate, isopropylcyclohexyl nitrate, l-methoxypropyl-2-nitrate, l-ethoxpropyl-2 nitrate, 1-isopropoxy-butyl nitrate, 1-ethoxylbutyl nitrate and mixtures thereof;
(b) the biodiesel blend comprises (1) between about 2% to about 98% by volume of a biodiesel comprising a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, or a mixture thereof, and (2) between about 2% to about 98% by volume of a diesel; and
(c) the diphenol and sterically hindered phenol are selected, respectively, from a compound of formula (I) and a compound of formula (II):
1 Il
wherein K1 and R3 are H or a tert-butyl group, and R2 is H, CH3, a tert-butyl group or -CH2-N(CH3)2.
6. The fuel composition of claim 1 , wherein:
(a) the fuel composition contains about 0.1% to about 0.35% by volume of a cetane improver;
(b) the biodiesel blend comprises (1) about 5% to about 30% by volume of a biodiesel comprising a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, or a mixture thereof, and (2) about 70 to about 90% by volume of a diesel;
(c) the diphenol is selected from the group consisting of tert- butylhydroquinone, 2-tert-butyl-l,4-hydroquinone, 2,5-di-tert-butyl- 1,4- hydroquinone, methylhydroquinone, and 2,5-di-tert.-octylhydroquinone, and mixtures thereof;
(d) the sterically hindered phenol is selected from the group consisting of 2, 6-di-tert-butylphenol, 2, 4-di-tert-butylphenol, 2, 6-di-tert-butyl- 4-methylphenol, 2-tert-butylphenol, 2, 4, 6-tπ-tert-butylphenol, and 2, 6-di-tert- butyl-4-dimethylaminomethylphenol, and mixtures thereof;
(e) the fuel composition contains about 100 milligrams of antioxidant per liter of the biodiesel blend to about 500 milligrams of antioxidant per liter of the biodiesel blend; and (f) the volumetric ratio of the diphenol to the sterically hindered phenol is between about 0.5 :1 to about 1.5: 1.
7. The fuel composition of claim 1, wherein:
(a) the fuel composition contains about 0.1% to about 0.35% by volume of a cetane improver;
(b) the biodiesel blend comprises (1) about 5% to about 30% by volume of a biodiesel comprising a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, or a mixture thereof, and (2) about 70 to about 95% by volume of a diesel; and
(c) the diphenol is selected from the group consisting of tert- butylhydroquinone, 2-tert-butyl-l,4-hydroquinone, 2,5-di-tert-butyl- 1,4- hydroquinone, methylhydroquinone, and 2,5-di-tert.-octylhydroquinone, and mixtures thereof;
(d) the sterically hindered phenol is selected from the group consisting of 2, 6-di-tert-butylphenol, 2, 4-di-tert-butylphenol, 2, 6-di-tert-butyl- 4-methylphenol, 2-tert-butylphenol, 2, 4, 6-tri-tert-butylphenol, and 2, 6-di-tert- butyl-4-dimethylaminomethylphenol, and mixtures thereof;
(e) the fuel composition contains about 200 milligrams of antioxidant per liter of the biodiesel blend to about 400 milligrams of antioxidant per liter of the biodiesel blend; and
(f) the volumetric ratio of the diphenol to the sterically hindered phenol is between about 0.75:1 to about l.: l .
8. The fuel composition of claim 1, wherein:
(a) the fuel composition contains about 0.1% to about 0.35% by volume of a cetane improver; (b) the biodiesel blend comprises (1) about 5% to about 15% by volume of a biodiesel comprising between about 50% to about 90% by weight of methyl, ethyl, and propyl esters of saturated and unsaturated fatty acids, and (2) about 85 to about 95% by volume of a diesel;
(c) the diphenol is selected from the group consisting of tert- butylhydroquinone, 2-tert-butyl- 1 ,4-hydroquinone, 2,5-di-tert-butyl- 1 ,4- hydroquinone, methylhydroquinone, and 2,5-di-tert.-octylhydroquinone, and mixtures thereof;
(d) the sterically hindered phenol is selected from the group consisting of 2, 6-di-tert-butylphenol, 2, 4-di-tert-butylphenol, 2, 6-di-tert-butyl- 4-methylphenol, 2-tert-butylphenol, 2, 4, 6-tri-tert-butylphenol, and 2, 6-di-tert- butyl-4-dimethylaminomethylphenol, and mixtures thereof;
(e) the fuel composition contains about 200 milligrams of antioxidant per liter of the biodiesel blend to about 400 milligrams of antioxidant per liter of the biodiesel blend; and
(f) the volumetric ratio of the diphenol to the sterically hindered phenol is between about 0.75: 1 to about l .:l.
9. The fuel composition of claim 1 , wherein the fuel composition further comprises a composition selected from the group consisting of an aromatic amine antioxidant and a performance additive.
10. The fuel composition of claim 1, wherein the fuel composition comprises:
(a) about 0.3% by volume of 2-ethylhexyl nitrate;
(b) a biodiesel blend comprising about 5% by volume of a biodiesel and about 95% by volume of a diesel; and (c) about 400 milligrams per liter of the biodiesel blend of an antioxidant comprising a mixture of 2-tert-butyl-l, 4-hydroquinone and a sterically hindered phenol, wherein the volumetric ratio of 2-tert-butyl-l, 4- hydroquinone to the sterically hindered phenol is about 1: 1.
11. The fuel composition of claim 1 , wherein the fuel composition comprises:
(a) about 0.3% by volume of 2-ethylhexyl nitrate;
(b) a biodiesel blend comprising about 5% by volume of a biodiesel and about 95% by volume of a diesel; and
(c) about 400 milligrams per liter of the biodiesel blend of an antioxidant comprising a mixture of 2-tert-butyl-l, 4-hydroquinone and a sterically hindered phenol selected from the group consisting of Ethanox® 4703 and Ethanox® 4733, wherein the volumetric ratio of 2-tert-butyl-l, 4- hydroquinone to the sterically hindered phenol is about 1 : 1.
12. The fuel composition of claim 11 , wherein the biodiesel comprises soybean methyl ester.
13. A fuel composition comprising:
(a) between about 0.01% to about 1% by volume of a cetane improver;
(b) a biodiesel comprising between about 50% to about 99% by weight of methyl, ethyl, and propyl esters of saturated and unsaturated fatty acids; and
(c) an antioxidant comprising a mixture of a diphenol and a sterically hindered phenol, wherein
(1) the amount of the antioxidant is (i) between about 20 milligrams per kilogram to about 10,000 milligrams per kilogram of the biodiesel, or (ii) is between about 16 milligrams per liter to about 8,000 milligrams per liter of the biodiesel, and
(2) wherein the volumetric ratio of the diphenol to the sterically hindered phenol is between about 0.01:1 to about 10:1.
14. The fuel composition of claim 13, wherein:
(a) the cetane improver is selected from the group consisting of 2-ethylhexyl nitrate, cyclohexyl nitrate, di-tert-butyl peroxide, methyl nitrate, ethyl nitrate, n-propyl nitrate, isopropyl nitrate, allyl nitrate, n-butyl nitrate, isobutyl nitrate, sec-butyl nitrate, tert-butyl nitrate, n-amyl nitrate, isoamyl nitrate, 2-amyl nitrate, 3-amyl nitrate, tert-amyl nitrate, n-hexyl nitrate, 2- ethylhexyl nitrate, n-heptyl nitrate, sec-heptyl nitrate, n-octyl nitrate, sec-octyl nitrate, n-nonyl nitrate, n-decyl nitrate, n-dodecyl nitrate, cyclopentylnitrate, cyclohexylnitrate, methylcyclohexyl nitrate, isopropylcyclohexyl nitrate, l-methoxypropyl-2-nitrate, l-ethoxpropyl-2 nitrate, 1-isopropoxy-butyl nitrate, 1-ethoxylbutyl nitrate and mixtures thereof;
(b) the biodiesel is formed by transesterifying an alcohol with a composition selected from the group consisting of soybean oil, rapeseed oil, palm oil, canola oil, sunflower oil, olive oil, corn oil, tallow oil, coconut oil, jatropha oil, yellow grease animal fats, used cooking oil, and mixtures thereof;
(c) the diphenol is selected from the group consisting of hydroquinone, tert-butylhydroquinone, 2-tert-butyl-l,4-hydroquinone, 2,5-di- tert-butyl-l,4-hydroquinone, methylhydroquinone, 2,5-di-tert- octylhydroquinone, and mixtures thereof; and
(d) the sterically hindered phenol is selected from the group consisting of 2, 6-di-tert-butylphenol, 2, 4-di-tert-butylphenol, 2, 6-di-tert-butyl- 4-methylphenol, 2-tert-butylphenol, 2, 4, 6-tri-tert-butylphenol, 2, 6-di-tert- butyl-4-dimethylaminomethylphenol, and mixtures thereof.
15. The fuel composition of claim 13, wherein:
(a) the cetane improver is selected from the group consisting of 2-ethylhexyl nitrate, cyclohexyl nitrate, di-tert-butyl peroxide, methyl nitrate, ethyl nitrate, n-propyl nitrate, isopropyl nitrate, allyl nitrate, n-butyl nitrate, isobutyl nitrate, sec-butyl nitrate, tert-butyl nitrate, n-amyl nitrate, isoamyl nitrate, 2-amyl nitrate, 3-amyl nitrate, tert-amyl nitrate, n-hexyl nitrate, 2- ethylhexyl nitrate, n-heptyl nitrate, sec-heptyl nitrate, n-octyl nitrate, sec-octyl nitrate, n-nonyl nitrate, n-decyl nitrate, n-dodecyl nitrate, cyclopentylnitrate, cyclohexylnitrate, methylcyclohexyl nitrate, isopropylcyclohexyl nitrate, l-methoxypropyl-2-nitrate, l-ethoxpropyl-2 nitrate, 1-isopropoxy-butyl nitrate, 1-ethoxylbutyl nitrate and mixtures thereof;
(b) the biodiesel comprises a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, and mixtures thereof;
(c) the diphenol is selected from the group consisting of hydroquinone, tert-butylhydroquinone, 2-tert-butyl-l,4-hydroquinone, 2,5-di- tert-butyl-l,4-hydroquinone, methylhydroquinone, 2,5-di-tert- octylhydroquinone, and mixtures thereof; and
(d) the sterically hindered phenol is selected from the group consisting of 2, 6-di-tert-butylphenol, 2, 4-di-tert-butylphenol, 2, 6-di-tert-butyl- 4-methylphenol, 2-tert-butylphenol, 2, 4, 6-tri-tert-butylphenol, 2, 6-di-tert- butyl-4-dimethylaminomethylphenol, and mixtures thereof.
16. the fuel composition of claim 13, wherein:
(a) the cetane improver is selected from the group consisting of 2-ethylhexyl nitrate, cyclohexyl nitrate, di-tert-butyl peroxide, methyl nitrate, ethyl nitrate, n-propyl nitrate, isopropyl nitrate, allyl nitrate, n-butyl nitrate, isobutyl nitrate, sec-butyl nitrate, tert-butyl nitrate, n-amyl nitrate, isoamyl nitrate, 2-amyl nitrate, 3-amyl nitrate, tert-amyl nitrate, n-hexyl nitrate, 2- ethylhexyl nitrate, n-heptyl nitrate, sec-heptyl nitrate, n-octyl nitrate, sec-octyl nitrate, n-nonyl nitrate, n-decyl nitrate, n-dodecyl nitrate, eye lopentyl nitrate, cyclohexylnitrate, methylcyclohexyl nitrate, isopropylcyclohexyl nitrate, l-methoxypropyl-2-nitrate, l-ethoxpropyl-2 nitrate, 1-isopropoxy-butyl nitrate, 1-ethoxylbutyl nitrate and mixtures thereof;
(b) the biodiesel comprises a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, and mixtures thereof; and
(c) the diphenol and sterically hindered phenol are selected, respectively, from a compound of formula (I) and a compound of formula (II):
wherein R1 and R3 are H or a tert-butyl group, and R2 is H, CH3, a tert-butyl group or -CH2-N(CH3)2.
17. The fuel composition of claim 13, wherein:
(a) the fuel composition contains about 0.1% to about 0.35% by volume of a cetane improver;
(b) the biodiesel comprises a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, and mixtures thereof;
(c) the diphenol is selected from the group consisting of tert- butylhydroquinone, 2-tert-butyl-l,4-hydroquinone, 2,5-di-tert-butyl- 1,4- hydroquinone, methylhydroquinone, and 2,5-di-tert-octylhydroquinone, and mixtures thereof;
(d) the sterically hindered phenol is selected from the group consisting of 2, 6-di-tert-butylphenol, 2, 4-di-tert-butylphenol, 2, 6-di-tert-butyl- 4-methylphenol, 2-tert-butylphenol, 2, 4, 6-tri-tert-butylphenol, and 2, 6-di-tert- butyl-4-dimethylaminomethylphenol, and mixtures thereof;
(e) the fuel composition contains about 100 milligrams of antioxidant per liter of the biodiesel to about 500 milligrams of antioxidant per liter of the biodiesel; and
(f) the volumetric ratio of the diphenol to the sterically hindered phenol is between about 0.5: 1 to about 1.5:1.
18. The fuel composition of claim 13, wherein:
(a) the fuel composition contains about 0.1% to about 0.35% by volume of a cetane improver;
(b) the biodiesel comprises a fatty acid ester selected from the group consisting of rapeseed methyl ester, a canola methyl ester, a soybean methyl ester, a corn oil methyl ester, and mixtures thereof;
(c) the diphenol is selected from the group consisting of tert- butylhydroquinone, 2-tert-butyl-l,4-hydroquinone, 2,5-di-tert-butyl-l ,4- hydroquinone, methylhydroquinone, and 2,5-di-tert.-octylhydroquinone, and mixtures thereof;
(d) the sterically hindered phenol is selected from the group consisting of 2, 6-di-tert-butylphenol, 2, 4-di-tert-butylphenol, 2, 6-di-tert-butyl- 4-methylphenol, 2-tert-butylphenol, 2, 4, 6-tri-tert-butylphenol, and 2, 6-di-tert- butyl-4-dimethylaminomethylphenol, and mixtures thereof; (e) the fuel composition contains about 400 milligrams of antioxidant per liter of the biodiesel; and
(f) the volumetric ratio of the diphenol to the sterically hindered phenol is between about 0.75: 1 to about l .:l.
19. The fuel composition of claim 13, wherein:
(a) the fuel composition contains about 0.1% to about 0.35% by volume of a cetane improver;
(b) the biodiesel comprises about 50% to about 99% by weight of methyl, ethyl, and propyl esters of saturated and unsaturated fatty acids;
(c) the diphenol is selected from the group consisting of tert- butylhydroquinone, 2-tert-butyl-l,4-hydroquinone, 2,5-di-tert-butyl- 1,4- hydroquinone, methylhydroquinone, and 2,5-di-tert.-octylhydroquinone, and mixtures thereof;
(d) the sterically hindered phenol is selected from the group consisting of 2, 6-di-tert-butylphenol, 2, 4-di-tert-butylphenol, 2, 6-di-tert-butyl- 4-methylphenol, 2-tert-butylphenol, 2, 4, 6-tri-tert-butylphenol, and 2, 6-di-tert- butyl-4-dimethylaminomethylphenol, and mixtures thereof;
(e) the fuel composition contains about 400 milligrams of antioxidant per liter of the biodiesel; and
(f) the volumetric ratio of the diphenol to the sterically hindered phenol is between about 0.75 :1 to about 1 :1.
20. The fuel composition of claim 13, wherein the fuel composition further comprises a composition selected from the group consisting of an aromatic amine antioxidant and a performance additive.
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Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103038258B (en) 2010-05-06 2017-02-15 诺华股份有限公司 Compositions and methods of use for therapeutic low density lipoprotein-related protein 6 (LRP6) antibodies
US20120233912A1 (en) * 2011-03-18 2012-09-20 Otkrytoe Aktsionernoe Obschestvo "Sterlitamaxky Neftekhimichesky Zavod" Antioxidant additive composition, a solution thereof, and a method for improving the storage stability of biodiesel fuel (variants)
US20130118058A1 (en) * 2011-05-10 2013-05-16 Thu Thi Le Nguyen Diesel microemulsion biofuels
US20130104447A1 (en) 2011-10-28 2013-05-02 Exxonmobil Research And Engineering Company Dye-stable biofuel blend compositions
CA2891520A1 (en) 2012-11-19 2014-05-22 The Lubrizol Corporation Coupled phenols for use in biodiesel engines
US11186789B2 (en) * 2017-07-18 2021-11-30 Hull Partners, Llc Biodiesel fuel mixtures
US11306266B2 (en) * 2017-07-31 2022-04-19 Hull Partners Llc Biodiesel fuel mixtures
KR102343229B1 (en) * 2019-06-10 2021-12-27 한국기계연구원 Bio Fuel Composition For Diesel Engine
CN111534337A (en) * 2020-05-12 2020-08-14 开封泓盈化工发展有限公司 Process for producing high-flash-point non-nitrate diesel oil cetane number anti-wear antistatic complexing agent
FR3125298A1 (en) * 2021-07-19 2023-01-20 Totalenergies Marketing Services Use of an additive composition to reduce emissions from diesel vehicles
FR3137105A1 (en) * 2022-06-23 2023-12-29 Veryone Ammonia-based compression engine fuel containing a combustion improvement additive.
FR3140091A1 (en) * 2022-09-27 2024-03-29 Totalenergies Onetech Ammonia-based fuel or fuel composition comprising a nitrate additive

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1847584A2 (en) * 2006-04-21 2007-10-24 Infineum International Limited Improvements in Biofuel
EP1847583A2 (en) * 2006-04-21 2007-10-24 Infineum International Limited Improvements in Biofuel
WO2008124390A2 (en) * 2007-04-04 2008-10-16 The Lubrizol Corporation A synergistic combination of a hindered phenol and nitrogen containing detergent for biodiesel fuel to improve oxidative stability

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5344468A (en) * 1991-06-14 1994-09-06 Ethyl Petroleum Additives, Inc. Organic phosphates and their use as wear inhibitors
US6197718B1 (en) * 1999-03-03 2001-03-06 Exxon Research And Engineering Company Catalyst activation method for selective cat naphtha hydrodesulfurization
US20050160662A1 (en) * 2002-06-11 2005-07-28 Oryxe Energy International, Inc. Method and composition for using stabilized beta-carotene as cetane improver in hydrocarbonaceous diesel fuels
WO2004087841A1 (en) * 2003-03-31 2004-10-14 Ciba Specialty Chemicals Holding Inc. Diesel fuel composition and a method to improve filterability of diesel fuel
WO2005087903A1 (en) * 2004-03-09 2005-09-22 Conocophillips Company Blends of synthetic distillate and biodiesel for low nitrogen oxide emissions from diesel engines
EP1951847A2 (en) * 2005-11-23 2008-08-06 Novus International, Inc. Biodiesel fuel compositions having increased oxidative stability
CA2641399C (en) * 2006-02-27 2015-11-24 Basf Se Use of polynuclear phenolic compounds as stabilisers
US7964002B2 (en) * 2006-06-14 2011-06-21 Chemtura Corporation Antioxidant additive for biodiesel fuels
CN101029257B (en) * 2007-03-26 2010-11-17 佛山市三水正合精细化工有限公司 Biological diesel-oil stabilized additive, its production and use
JP2010522809A (en) * 2007-03-28 2010-07-08 アルベマール・コーポレーシヨン Antioxidant mixture for fatty acid methyl esters (biodiesel)
US8748357B2 (en) * 2008-07-15 2014-06-10 Exxonmobil Research And Engineering Company Method for stabilizing diesel engine lubricating oil against degradation by biodiesel fuel

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1847584A2 (en) * 2006-04-21 2007-10-24 Infineum International Limited Improvements in Biofuel
EP1847583A2 (en) * 2006-04-21 2007-10-24 Infineum International Limited Improvements in Biofuel
WO2008124390A2 (en) * 2007-04-04 2008-10-16 The Lubrizol Corporation A synergistic combination of a hindered phenol and nitrogen containing detergent for biodiesel fuel to improve oxidative stability

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
DATABASE WPI Week 200808 Thomson Scientific, London, GB; AN 2008-B17945 XP002712448, -& CN 101 029 257 A (FOSHAN SANSHUI ZHENGHE FINE CHEM CO LTD) 5 September 2007 (2007-09-05) *
RHET GUZMAN ET AL: "Synergistic Effects of Antioxidants on the Oxidative Stability of Soybean Oil- and Poultry Fat-Based Biodiesel", JOURNAL OF THE AMERICAN OIL CHEMISTS' SOCIETY, vol. 86, no. 5, 1 May 2009 (2009-05-01), pages 459-467, XP55065390, ISSN: 0003-021X, DOI: 10.1007/s11746-009-1373-8 *
See also references of WO2011014424A1 *

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US20110023351A1 (en) 2011-02-03
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