Compositions and methods for inhibiting oxidation of natural oil-based compositions using aminophenol antioxidants

Abstract

Compositions comprising oils of plant or animal origin, such as fatty acid alkyl esters, are stabilized against oxidation using oxidized aminophenol antioxidants. The aminophenol includes one or two carbon-containing groups including hydroxyl groups and / or ether groups separated from an N atom by one or more carbon atoms. The oxidized aminophenol antioxidants effectively control oxidation in moderate and even low amounts, can be used in a variety of different oil and fatty acid methyl ester formulations, and are effective at elevated temperatures, and exhibit significantly superior performance to conventional antioxidants.

Description

[0001] Cross - Reference to Related Applications

[0002] This application claims the benefit of U.S. Provisional Patent Application Serial No. 63 / 434,274, filed on December 21, 2022, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] The present invention relates to the use of aminophenol antioxidants to inhibit the oxidation of oxidizable compounds in natural oils or materials prepared therefrom, such as fuel and lubricant compositions, like biodiesel and bio - lubricants. Background Art

[0004] Antioxidants are used in various compositions and industries. For example, antioxidants are used to inhibit the chemical oxidation of compositions obtained from the petroleum and natural gas industries. Antioxidants also play an important role as food preservatives, typically added to various food compositions to maintain the properties of the food.

[0005] Hydrocarbon - containing compositions can benefit from the use of antioxidants. In fats and oils, antioxidants can inhibit oxidation reactions that would otherwise have an adverse effect on the chemical properties of such fats and oils. Natural fats and oils contain fatty acid moieties that can have unsaturated regions highly sensitive to oxidation. In food, the oxidation of edible fats produces unpleasant odors and flavors, leading to food spoilage. Oxygen and sunlight cause the oxidation of hydrocarbons, and thus, exposure to oxygen and sunlight can result in oxidation.

[0006] Antioxidants are also added to fuels (such as gasoline and gasoline / ethanol blends) and lubricants to prevent the oxidation of hydrocarbons therein. Gasoline fuels are prone to oxidation when exposed to conditions such as heat, oxygen, and ultraviolet light. Oxidation products form gums or sediments inside the fuel, leading to problems such as clogging and corrosion in internal combustion engines. Antioxidants can prevent the polymerization of compounds in gasoline, which otherwise would produce residues that damage the internal combustion engine.

[0007] As an alternative to fuels and lubricants obtained from fossil sources, the use of renewable feedstocks to produce biofuels and lubricants has become more interesting. Specifically, biodiesel fuels and bio-lubricants have gained popularity due to their performance characteristics, which can be similar and, in some cases, superior to petroleum-based fuels and lubricants. Biodiesel and bio-lubricants are typically derived from feedstocks that are vegetable oils (i.e., glycerides), such as soybean oil, palm oil, rapeseed oil, sunflower oil, and coconut oil. These oils are usually converted into fatty acid alkyl esters through transesterification reactions. The most common transesterification method reacts the oil with methanol under basic catalysis to produce fatty acid methyl esters (FAME). While the use of biodiesel and bio-lubricants offers great commercial potential, there are various technical challenges associated with their preparation and use.

[0008] One challenge in the preparation and use of biodiesel and bio-lubricants is maintaining the oxidative stability of these compositions. While vegetable oil feedstocks have some protection against oxidation through naturally occurring antioxidants such as tocopherols, the manufacturing and refining processes of biodiesel and bio-lubricants can remove these natural antioxidants.

[0009] In the absence of antioxidants, the reduced oxidative stability of biodiesel and bio-lubricants is sensitive to oxidative degradation. Oxidized biodiesel compositions can deteriorate the properties of biodiesel and cause problems in its use. The degradation of fatty acid esters can be caused and accelerated by factors such as contaminants like trace metals, contact with metal surfaces, aeration, and physical factors such as heat and ultraviolet light. For example, the oxidation of biodiesel components through interaction with air and metal surfaces leads to the formation of hydroperoxide radicals. These radicals promote free radical chain reactions that result in the formation of low molecular weight oxidation compounds such as acids, aldehydes, and ketones. Polymer gums are also formed due to oxidation. Polymer gums cause many problems, such as inadequate fuel combustion, deposits on engine components (such as injectors and pistons), and blockages in injectors and fuel lines. Thus, oxidation not only reduces the effectiveness of biodiesel but also causes long-term mechanical problems in engines and related components.

[0010] Antioxidants are preferably used in biodiesel and bio-lubricants to prevent the oxidation of components therein such as FAME. However, the use of antioxidants can be challenging. Some conventional antioxidants need to be used at elevated concentrations to function as antioxidants, but typically these antioxidants are not very effective in controlling peroxide formation due to the interaction of biodiesel with air. First, the antioxidant should be compatible with bio-based fuels and lubricants derived from a variety of plant-based materials and should not exhibit any adverse interactions with components in the bio-based composition. In addition, the antioxidant should be compatible with biodiesel blends, such as biodiesel containing a blend of (plant-based) biodiesel and petroleum-derived diesel. Further, the added antioxidant should not adversely affect the properties of these materials, such as ignition and combustion properties, and the flow properties of biodiesel, especially at low temperatures. Additionally, the added antioxidant should also cause minimal environmental impact, especially when used with biodiesel, such as not promoting the formation of undesirable suspended particles. Some conventional antioxidants contain sulfur chemicals, the use of which may be undesirable from an environmental perspective. SUMMARY OF THE INVENTION

[0011] The present disclosure relates to compositions comprising natural oils or derivatives from natural oils that utilize oxidation aminophenol antioxidants according to the chemistries described herein. The oxidation aminophenol antioxidants provide excellent antioxidant properties to compositions comprising natural oils or materials prepared from natural oils, such as bio-based fuels and lubricants, like biodiesel and bio-lubricants. In addition, the oxidation aminophenol antioxidants do not impair the properties of compositions comprising natural oils or natural oil-derived materials. For example, the aminophenol antioxidants can be included in biodiesel or bio-lubricant compositions without impairing important properties such as combustion properties, lubricity, and low-temperature flow properties.

[0012] Experimental studies associated with aspects of the present disclosure have revealed that moderate and even low amounts of the oxidation aminophenol antioxidants of the present disclosure are effective in controlling the oxidation of natural oil-based compositions. The oxidation aminophenol antioxidants also demonstrate effectiveness as antioxidants in a variety of different natural oil derivatives, specifically fatty acid methyl ester formulations, thus exemplifying their usefulness as antioxidants for a variety of natural oil-based compositions, including biodiesel and bio-lubricant compositions. Additionally, the oxidation aminophenol antioxidants of the present disclosure are effective under elevated temperature test conditions, thus supporting their use in higher temperature processing, storage, and use scenarios. Subsequently, the oxidation aminophenol antioxidants of the present disclosure can provide improved oxidation stability, which for uses such as biodiesel, reduces or eliminates sedimentation and gum formation when it is used in an engine, and also reduces corrosion and fouling of diesel engine components.

[0013] Thus, in one embodiment, the present invention provides (ai) esters of fatty acids of plant origin, (aii) oils of plant origin, or both (ai) and (aii), and (b) an oxidized aminophenol antioxidant of formula I;

[0014]

[0015] In formula I, -R 1 , -R 2 , -R 3 , -R 4 and -R 5 are independently selected from -H, -OH, alkyl, aryl, alkylaryl and arylalkyl and -NR 8 R 9 , wherein at least one of -R 1 , -R 2 , -R 3 , -R 4 and -R 5 is -OH. R 8 and R 9 are independently selected from -H, alkyl, aryl, alkylaryl and arylalkyl, and R 6 / R 7 , or any two adjacent groups of -R 1 , -R 2 , -R 3 , -R 4 and -R 5 form one or more ring structures. One or both of R 6 and R 7 is (i) a carbon-containing group which comprises (I) one or more hydroxy groups, (II) one or more ether groups, or both (I) and (II), which is separated from the N atom by one or more carbon atoms; if R 6 or R 7 is not (i), then it is selected from -H, alkyl, aryl, alkylaryl and arylalkyl. One or more hydroxy groups and / or one or more ether groups.

[0016] In an embodiment, one or both of R 6 and R 7 has the formula: -(CR 10 2) q (CHOH)(CH2)zR 11 , wherein R 10 is independently selected from -H and alkyl, wherein q and z are independently (-) (covalent bond), or an integer in the range of 1 to 12, preferably (-), 1 or 2, and R 11Selected from C1 to C24 linear, branched or cyclic alkyl, aryl, alkyl-aryl and aryl-alkyl. In an embodiment, R 10 is -H; q is 1; z is (-); and R 11 is C1 to C18 linear, branched or cyclic alkyl, aryl, alkyl-aryl and aryl-alkyl.

[0017] In an embodiment, one or both of R 6 and R 7 has the formula: -(CR 10 2) q (CHOH)(R 12 O) z R 11 wherein R 10 is independently selected from -H and alkyl, q is (-) (covalent bond) or an integer in the range of 1 to 12, preferably (-), 1 or 2, R 11 is selected from C1 to C24 linear, branched or cyclic alkyl, aryl, alkyl-aryl and aryl-alkyl, and R 12 is independently selected from -(CH2) w -, where w is 1, 2 or 3, and z is an integer in the range of 1 to 5. In an embodiment, R 10 is -H; q is 1; z is 1; w is 1 or 2, and R 11 is C1 to C18 linear, branched or cyclic alkyl, aryl, alkyl-aryl and aryl-alkyl.

[0018] In an embodiment, the esters of fatty acids of plant origin include: (1) esters of triglycerides of plant origin, such as methyl esters, (2) esters of free fatty acids of plant origin, such as methyl esters, or both (1) and (2). In an embodiment, the aminophenol antioxidant of formula I is present in the composition in an amount in the range of 100 ppm to 2500 ppm or in an amount in the range of 250 ppm to 1500 ppm.

[0019] The oxidation aminophenol antioxidants of the present disclosure generally perform better than comparative antioxidants in oxidation stability tests. In experimental studies associated with the present disclosure, the Rancimat test (e.g., standard test method EN 14112) is conducted to measure the degradation products resulting from the oxidation of oxidizable components (such as fatty acid methyl esters) of an oil or oil derivative composition. The test uses a specified amount of oil / oil derivative and antioxidant and is conducted at a specified air flow rate and temperature. The induction period is measured, where a longer induction period reflects relatively better performance of the antioxidant. In some embodiments, the oxidation aminophenol antioxidant can extend the induction period by a period greater than 50% compared to the induction time in the absence of an antioxidant, or by a period greater than 60%, 70%, 80%, 90%, 100%, or 110% compared to the induction time in the absence of an antioxidant, and by a period up to 275%, 250%, 225%, 200%, 175%, 160%, 150%, 140%, 130%, or up to 125% compared to the induction time in the absence of an antioxidant. On the other hand, comparative antioxidants generally do not extend the induction period by more than 50% of the induction time in the absence of an antioxidant.

[0020] In another embodiment, the present invention provides a method for inhibiting the oxidation of esters of fatty acids of plant origin or oils of plant origin in a composition. The method includes the step of adding an aminophenol antioxidant to a composition comprising (ai) an ester of a fatty acid of plant origin, (aii) an oil of plant origin, or both (ai) and (aii), wherein the aminophenol antioxidant is a compound of Formula I.

[0021] In some embodiments of the method, the level at which the aminophenol antioxidant inhibits the oxidation of the ester or the oil is 1.4 times the oxidation level in the absence of the oxidation aminophenol antioxidant.

[0022] The oxidation aminophenol antioxidant can prevent the oxidation of the carbon-carbon double bond of fatty acid alkyl esters, resulting in the formation of epoxide and alcohol compounds, which otherwise can promote metal corrosion. Biodiesel and lubricity compositions containing fatty acid alkyl esters can suffer from such oxidation after being exposed to air for a period of time, and the oxidation aminophenol antioxidant can be used as an antioxidant to prevent the deterioration of such compositions. DETAILED DESCRIPTION OF THE INVENTION

[0024] Although the present disclosure provides references to preferred embodiments, those skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. References to various embodiments do not limit the scope of the claims appended hereto. Additionally, any examples set forth in this specification are not intended to be limiting and merely illustrate some of the many possible embodiments of the appended claims.

[0025] Additional advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention through routine experimentation.

[0026] The present disclosure describes compositions comprising natural oils or derivatives thereof, the compositions comprising an aminophenol antioxidant according to Formula I as described herein. Exemplary compositions include biofuels and lubricants, as exemplified by biodiesel and bio-lubricants comprising the aminophenol antioxidant. The aminophenol antioxidant provides excellent antioxidant properties to the compositions incorporating the antioxidant. Additionally, the aminophenol antioxidant is compatible with natural oils and their derivatives. For example, the aminophenol antioxidant does not impair the properties of biodiesel and bio-lubricants, such as combustion properties, lubricity, and low temperature flow properties.

[0027] Compositions comprising esters of fatty acids of plant origin and / or the essential components of oils of plant origin together with the aminophenol antioxidant may optionally contain other components in the composition (e.g., described according to the composition "comprising" esters of fatty acids / oils of plant origin and the aminophenol antioxidant). For example, the compositions of the present disclosure may contain other components such as solvents, or other additives such as surfactants, dispersants, etc. If the optional component is present in the composition, it may be described in terms of weight percentage (e.g., such as mg / L or parts per million (ppm)) or molar amount. Alternatively, any optional component may be described in relation to the aminophenol antioxidant, such as whether the optional component is present in an amount greater than, less than, or equal to the amount of the aminophenol antioxidant, or may be more specifically described in terms of the ratio (e.g., molar ratio) or range of ratios between the optional component and the aminophenol antioxidant.

[0028] As used herein, the term "optional" or "optionally" means that the subsequently described object (e.g., a compound) or event (e.g., a processing step), amount, or circumstance may but need not occur, and the description includes instances where the object, event, amount, or circumstance occurs and instances where it does not occur.

[0029] The compositions of the present disclosure can include those listed compounds and optionally can include other components in the composition, but in very small amounts (e.g., as described by a composition of the term "consisting essentially of the listed components"). For example, such compositions can include one or more other components, but in an amount not greater than about 1 wt%, about 0.5 wt%, about 0.1 wt%, about 0.05 wt%, or about 0.01 wt% of the total composition. In a composition "consisting" of the listed components, there are no other measurable amounts of components other than the listed components.

[0030] Similarly, in some embodiments, the chemical composition of the compounds of the present disclosure (including naphthoquinones and hydroxylamines) can be described by compounds of the term "consisting of certain atoms or certain chemical groups". For example, in an embodiment of the present disclosure, a compound such as an aminophenol antioxidant can consist of carbon (C), hydrogen (H), oxygen (O), and nitrogen (N), and there will be no other types of atoms in the compound other than C, H, O, and N.

[0031] As used herein, the terms "substantially" and "consisting essentially of" modifying, for example, the type or amount of ingredients in a composition, properties, measurable amounts, methods, locations, values, or ranges when describing embodiments of the present disclosure mean changes that do not affect all of the described composition, properties, amounts, methods, locations, values, or their ranges in a manner adverse to the intended composition, property, amount, method, location, value, or its range. Examples of intended properties include (by way of non-limiting example only) dispersibility, stability, rate, solubility, etc.; intended values include the weight of added components, the concentration of added components, etc. Regarding the effect on modified methods includes effects caused by changes in the type or amount of materials used in the process, changes in machine settings, the effect of environmental conditions on the process, etc., where the manner or degree of the effect does not adversely affect one or more intended properties or results; and similar approximate considerations. In cases modified by the terms "substantially" or "consisting essentially of", the appended claims include equivalents of these types and amounts of materials.

[0032] As used herein, the term "about" in connection with the description of embodiments of the present disclosure, such as amounts, concentrations, volumes, process temperatures, process times, yields, flow rates, pressures, and similar values and ranges thereof of ingredients in a composition, refers to amounts that can vary, for example, due to typical measurement and processing procedures used in the preparation of compounds, compositions, concentrates, or formulated uses; due to human error that occurs inadvertently in these procedures; due to differences in the manufacture, source, or purity of starting materials or ingredients used to perform the method, and similar considerations. The term "about" also encompasses amounts that differ from the specific starting concentration or mixture due to the aging of a formulation, and amounts that differ from the specific starting concentration or mixture due to mixing or processing of a formulation. When modified by the term "about", the appended claims include equivalents of these amounts. Additionally, unless the context clearly dictates otherwise, when "about" is used to describe any range of values, such as "about 1 to 5", the recited range is meant to include "1 to 5" and "about 1 to about 5" and "1 to about 5" and "about 1 to 5".

[0033] Some of the R groups in the formulas of the present disclosure can include hydrocarbon-containing groups such as alkyl groups, which include straight-chain, branched-chain, and cyclic alkyl groups, aryl groups, alkylaryl groups (e.g., phenyl-propyl), arylalkyl groups (e.g., propyl-phenyl), and combinations thereof. In some embodiments, the hydrocarbon groups of the formulas of the present disclosure can be defined by the number of carbon atoms in the group, such as 1 to 12 carbons, 1 to 10 carbons, 1 to 8 carbons, 1 to 6 carbons, 1 to 5 carbons, 1 to 4 carbons, or 1 to 3 carbons.

[0034] The compositions and methods of the present disclosure include or use an oxidized aminophenol compound. The oxidized aminophenol compound includes at least an unsaturated 6-carbon ring structure having at least one hydroxyl group bonded to an aromatic ring carbon and at least one nitrogen atom of a secondary or tertiary amine group bonded to an aromatic ring carbon, wherein the nitrogen atom of the secondary or tertiary amine group is linked to a (first) carbon-containing group (and optionally a second carbon-containing group), which includes one or more hydroxyl groups and / or ether groups separated from the N atom by one or more carbon atoms. Preferably, the (first) carbon-containing group (and optionally the second carbon-containing group) includes one or more hydroxyl groups and one or more ether groups separated from the N atom by one or more carbon atoms. Preferably, the hydroxyl group and the ether group are separated from the nitrogen by two carbon atoms or three carbon atoms. Atoms on the aromatic ring that are not bonded to the secondary or tertiary amine group and the hydroxyl group can be bonded to a hydrogen atom, a hydrocarbon group including an aryl group and / or an alkyl group, or can form a ring structure (e.g., a fused ring structure with the aromatic ring). Exemplary compounds of the present disclosure that include a hydroxyl group bonded to a ring atom of the unsaturated 6-carbon ring include those based on phenol, catechol, resorcinol, hydroquinone, hydroxyhydroquinone, or phloroglucinol. Exemplary compounds also include those compounds based on hydroxyl-containing fused aromatic chemistries, such as naphthol, hydroxy-anthracene, or indanol.

[0035] In embodiments, the first and / or second carbon-containing groups of the secondary or tertiary amine group include: a number of carbon atoms in the range of from 1 to about 24, 2 to about 23, 2 to about 22, 3 to about 24, or 4 to about 24; a number of hydrogen atoms in the range of from 3 to about 40, 4 to about 38, or 5 to about 35; a number of oxygen atoms of 1, 2, 3, or 4; or any combination thereof. In preferred embodiments, the carbon-containing groups of the secondary or tertiary amine group contain only carbon, oxygen, and hydrogen.

[0036] In some embodiments, the present disclosure provides "bis" compounds, wherein the compound contains a tertiary amine group and the first and second carbon-containing groups bonded to the nitrogen atom of the tertiary amine group are the same. For example, in the aminophenol compound 4-bis[(3-butoxy-2-hydroxy-propyl)amino]phenol, the first and second carbon-containing groups are the same and are -(CH2CHOHCH2)O(CH2)3CH3.

[0037] The oxidation aminophenol antioxidant compounds of the present disclosure are described with reference to Formula I:

[0038]

[0039] In Formula I, -R 1 、-R 2 、-R 3 、-R 4 and -R 5 are independently selected from -H, -OH, alkyl, aryl, alkylaryl, and arylalkyl, and -NR 8 R 9 , wherein at least one of -R 1 、-R 2 、-R 3 、-R 4 and -R 5 is -OH. R 8 and R 9 are independently selected from -H, alkyl, aryl, alkylaryl, and arylalkyl, and R 6 / R 7 , or any two adjacent groups of -R 1 、-R 2 、-R 3 、-R 4 and -R 5 form one or more ring structures. R 6 and R 7One or both of them are (i) a carbon-containing group that contains (I) one or more hydroxyl groups, (II) one or more ether groups, or both (I) and (II), which are separated from the N atom by one or more carbon atoms; if R 6 or R 7 is not (i), then it is selected from -H, alkyl, aryl, alkylaryl, and arylalkyl.

[0040] can be -R 1 、-R 2 、-R 3 、-R 4 、-R 5 、-R 8 and -R 9 One or more exemplary alkyl groups among them can be alkyl groups having a carbon atom number in the range of 1 to 18, 1 to 12, 1 to 8, 1 to 6, or 1 to 3, and are selected from straight-chain, branched-chain, and cyclic alkyl groups. Exemplary alkyl group types include, but are not limited to:

[0041] methyl,

[0042] ethyl,

[0043] propyl, isopropyl,

[0044] butyl, isobutyl, sec-butyl, tert-butyl,

[0045] pentyl, cyclopentyl, isopentyl, neopentyl,

[0046] hexyl, cyclohexyl, 1-methylbutyl, 2-methylbutyl, and 3-methylbutyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, or 2,2-dimethylpropyl, 1-ethyl-propyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, or 4-methylpentyl, 1,1-dimethylbutyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl, 2,2-dimethylbutyl, 2,3-dimethylbutyl, or 3,3-dimethylbutyl, 1-ethylbutyl or 2-ethylbutyl, 1-ethyl-1-methylpropyl, and 1,1,2-trimethylpropyl or 1,2,2-trimethylpropyl, methylcyclopentyl;

[0047] heptyl, 2-methylhexyl, 3-methylhexyl, 4-methylhexyl, 5-methylhexyl, 3-ethylpentyl, 2,2,3-trimethylbutyl, 2,2-dimethylpentyl, 2,3-dimethylpentyl, 2,4-dimethylpentyl, 3,3-dimethylpentyl, 3,4-dimethylpentyl, 4,4-dimethylpentyl, cycloheptyl, 1-methylcyclohexyl, and 2-methylcyclohexyl;

[0048] octyl, 2-methylheptyl, 3-methylheptyl, 4-methylheptyl, 2-ethylhexyl, 3-ethylhexyl, 4-ethylhexyl, 5-ethylhexyl, 2,2-dimethylhexyl, 2,3-dimethylhexyl, 2,4-dimethylhexyl, 2,5-dimethylhexyl, 3,3-dimethylhexyl, 3,4-dimethylhexyl, 3-ethyl-2-methylpentyl, 3-ethyl-3-methylpentyl, 2,2,3-trimethylpentyl, 2,2,4-trimethylpentyl, 2,3,3-trimethylpentyl, 2,3,4-trimethylpentyl, and 2,2,3,3-tetramethylbutyl;

[0049] nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyloxy.

[0050] can be -R 1 , -R 2 , -R 3 , -R 4 , -R 5 , -R 8 and -R 9 Exemplary alkylaryl groups that can be one or more of -R

[0051] can be -R 1 , -R 2 , -R 3 , -R 4 , -R 5 , -R 8 and -R 9 Exemplary arylalkyl groups that can be one or more of -R

[0052] In embodiments, in one or both of R 6 and R 7 , one or more hydroxyl groups and / or ether groups are separated from the N atom by two or more carbon atoms, preferably two carbon atoms.

[0053] In embodiments, one or both of R 6 and R 7 include one or more oxygen atoms in the form of one or more hydroxyl groups. In some embodiments, one or both of R 6 and R 7One or both of them have the formula: -(CR 10 2) q (CHOH)(CH2) z R 11 , where R 10 is independently selected from -H and alkyl, where q and z are independently (-) (covalent bond) or integers in the range of 1 to 12, and R 11 is selected from C1 to C24 straight-chain, branched-chain or cyclic alkyl, aryl, alkyl-aryl and aryl-alkyl. Preferably, q and z are independently (-), 1 or 2. Even more preferably R 10 is -H; q is 1; z is (-); and R 11 is selected from C1 to C18 straight-chain, branched-chain or cyclic alkyl, aryl, alkyl-aryl and aryl-alkyl groups. Exemplary alkyl, alkyl-aryl and aryl-alkyl groups are described herein. The formula: -(CR 10 2) q (CHOH)(CH2) z R 11 Exemplary substances include the following groups:

[0054]

[0055] In an embodiment, one or both of R 6 and R 7 contain two or more oxygen atoms, at least one in the form of a hydroxyl group and at least one in the form of an ether group. In some embodiments, one or both of R 6 and R 7 have the formula: -(CR 10 2) q (CHOH)(R 12 O) z R 11 , where R 10 is independently selected from -H and alkyl, where q is (-) (covalent bond) or an integer in the range of 1 to 12, and R 11 is selected from C1 to C24 straight-chain, branched-chain or cyclic alkyl, aryl, alkyl-aryl and aryl-alkyl groups, and R 12 is independently selected from -(CH2) w -, where w is 1, 2 or 3, and where z is an integer in the range of 1 to 100, 1 to 50, 1 to 25, 1 to 15, 1 to 10, 1 to 5, or t is 2, 3 or 4. In a preferred aspect, R 10 is -H; q is 1; z is 1; w is 1 or 2, and R 11 is C1 to C18 straight-chain, branched-chain or cyclic alkyl, aryl, alkyl-aryl and aryl-alkyl. Exemplary alkyl, alkyl-aryl and aryl-alkyl groups are described herein.

[0056] Formula: (CR 10 2) q (CHOH)(R 12 O) z R 11 Exemplary substances of the formula: include the following groups:

[0057]

[0058] Preferred compounds of formula I include those in which -R 1 , -R 2 , -R 3 , -R 4 and -R 5 One or more of them are -OH, and those -R 1 , -R 2 , -R 3 , -R 4 and -R 5 that are not -OH are -H. For example, some preferred compounds of the present disclosure have the following sub-formula Ia, where R 6 and R 7 have the meanings described herein.

[0059]

[0060] Exemplary compounds of sub-formula Ia (where R 6 and R 7 both have the formula: -(CR 10 2) q (CHOH)(CH2)zR 11Comprising: 4-bis[(2-hydroxyethyl)amino]phenol, 4-bis[(2-hydroxypropyl)amino]phenol, 4-bis[(2-hydroxybutyl)amino]phenol, 4-bis[(2-hydroxypentyl)amino]phenol, 4-bis[(2-hydroxyhexyl)amino]phenol, 4-bis[(2-hydroxy-2-phenyl)amino]phenol, 4-bis[(2-hydroxy-2-phenethyl)amino]phenol, 4-bis[(2-hydroxyheptyl)amino]phenol, 4-bis[(2-hydroxyoctyl)amino]phenol, 4-bis[(2-hydroxynonyl)amino]phenol, 4-bis[(2-hydroxydecyl)amino]phenol, 4-bis[(2-hydroxyundecyl)amino]phenol, 4-bis[(2-hydroxydodecyl)amino]phenol, 4-bis[(2-hydroxytridecyl)amino]phenol, 4-bis[(2-hydroxytetradecyl)amino]phenol, 4-bis[(2-hydroxypentadecyl)amino]phenol, 4-bis[(2-hydroxyhexadecyl)amino]phenol, 4-bis[(2-hydroxyheptadecyl)amino]phenol, 4-bis[(2-hydroxyoctadecyl)amino]phenol, 4-bis[(2-hydroxyalkenyl)amino]phenol, 4-bis[(2-hydroxynonadecyl)amino]phenol, 4-bis[(2-hydroxyeicosyl)amino]phenol, 4-bis[(2-hydroxyheneicosyl)amino]phenol, 4-bis[(2-hydroxydocosyl)amino]phenol and 4-bis[(2-hydroxyoctosyl)amino]phenol.

[0061] Other exemplary compounds of formula Ia, wherein R 6 and R 7 both have the formula: -(CR 10 2) q (CHOH)(R 12 O) z R 11including but not limited to: 4-bis[(3-methoxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-ethoxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-propoxy-2-hydroxy)-propyl)amino]phenol, 4-bis[(3-butoxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-pentyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-hexyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-heptyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-octyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-nonyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-decyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-undecyloxy-2)-hydroxy-propyl)amino]phenol, 4-bis[(3-dodecyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-tridecyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-tetradecyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-pentadecyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-hexadecyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-heptadecyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-octadecyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-alkenyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-nonadecyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-icosyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-heneicosyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-docosyloxy-2-hydroxy-propyl)amino]phenol, and 4-bis[(3-tricosyloxy-2-hydroxy-propyl)amino]phenol.

[0062] An aromatic compound of the present disclosure that can be used to synthesize the antioxidant compounds of the present disclosure includes an aminophenol compound as described herein, which can be prepared using the methods according to the present disclosure. In some practice modes, and generally, an aryl group reactant having a primary amine group and a hydroxyl group, such as 4-aminophenol, reacts with a carbon- and oxygen-containing reactant that is capable of reacting with the primary (and optionally secondary) amine group to provide a product such as described herein. When reacting with the amine group, the carbon- and oxygen-containing reactant can provide group R 6 and / or R 7 either or both of which can have the formula: -(CR 10 2) q (CHOH)(CH2) z R 11 or (CR 10 2) q (CHOH)(R12 O) z R 11 。

[0063] In some practice modes, the reactants include epoxyethyl groups or oxetanyl groups as amine-reactive groups. The epoxyethane-containing reactants and oxetane-containing reactants can contain the desired carbon chemistry and can also contain additional oxygen atoms, such as in the form of ether groups. Exemplary epoxyethane-containing reactants are glycidyl ethers, such as alkyl glycidyl ethers.

[0064] In some practice modes, the epoxyethane-containing reactant has Formula II:

[0065]

[0066] wherein R 13 is -(CH2)- or -(CH2CH2)-, wherein R 14 is -(CH2) w -, where w is an integer in the range of 1 to 3, t is an integer in the range of 1 to 100, 1 to 50, 1 to 25, 1 to 15, 1 to 10, 1 to 5, or t is 1, 2, 3, or 4, and wherein R 15 is R 10 , as described herein, optionally substituted with one or more hydroxyl groups.

[0067] In a preparation mode, the aminophenol compound as described herein can be reacted with a carbon- and oxygen-containing reactant (e.g., glycidyl ether) in a desired molar ratio. The ratio can be an equimolar ratio or a ratio in which the carbon- and oxygen-containing reactant is in excess of the molar ratio of the aminophenol compound. In an exemplary practice mode, the carbon- and oxygen-containing reactant reacts in an excess of about twice the molar amount of the aminophenol compound.

[0068] An exemplary reaction is shown below, where 4-aminophenol and butyl glycidyl ether react at a molar ratio of 1:2, respectively, to provide 4-bis[(3-butoxy-2-hydroxy-propyl)amino]phenol:

[0069]

[0070] In some embodiments, the reaction product can include a mixture of oxidized aminophenol products that contain oxidized aminophenol, wherein (a) R 6 and R 7 are both carbon-containing groups having one or more oxygen atoms (e.g., hydroxyl and ether, such as -(CR 10 2) q (CHOH)(R 12 O) z R11 ), and (b) wherein R 6 and R 7 one of which is a carbon-containing group having one or more oxygen atoms (e.g., -(CR 10 2) q (CHOH)(R 12 O) z R 11 ), and the other is -H. Such mixtures can be formed accordingly by using glycidyl ether reactants and aminophenols in a molar ratio greater than 1:1 but less than 2:1.

[0071] In some practice modes, the aminophenol reactant and the carbon- and oxygen-containing reactant (e.g., an ethylene oxide- or oxetane-containing reactant) react at a temperature at which one or both reactants are in the liquid phase. In some practice modes, the ethylene oxide / oxetane-containing reactant is in the liquid phase at the desired reaction temperature, and it solvates the aminophenol-containing reactant. At this point, the melting point of the aminophenol-containing reactant can be higher than the melting point of the carbon- and oxygen-containing reactant. In embodiments where the reactants melt and / or solvate at the desired reaction temperature, any other components (such as organic solvents commonly used in reaction schemes) can be optional and not necessary. Thus, organic solvents can be excluded from the reaction process. In addition, components such as catalysts can also be optional and thus not necessary. In certain practice modes, the synthesis method does not include the use of (a) organic solvents, (b) catalysts, or both (a) and (b).

[0072] Exemplary reaction temperatures can be in the range of about room temperature (about 25 °C) to about 250 °C, about 40 °C to about 200 °C, or about 50 °C to about 175 °C.

[0073] Alternatively, the aminophenol and the carbon- and oxygen-containing reactant can be refluxed in an organic solvent (such as an alcohol, such as methanol, butyl carbitol, and butyl glycol) at an elevated temperature (e.g., >100 °C).

[0074] The composition comprising oxidized aminophenol and any one or more optional components can be in a desired form, such as in liquid form, dry form, or in the form of a suspension or dispersion. The oxidized aminophenol can be in a desired physical state in the composition, such as in a dissolved state, a partially dissolved state, a suspended state, or a dry mixture. The oxidized aminophenol can optionally be in particulate form in the composition. If the oxidized aminophenol is in particulate form, the particles can optionally be described according to particle size (e.g., particles within a particle size range) and / or shape. The form of the composition and the state of the components therein can be selected by choosing the oxidized aminophenol in understanding its physical properties.

[0075] The form of the composition and the state of the components therein can also be affected by the inclusion of one or more optional components, such as solvents, or solvent mixtures, or other excipient compounds different from the amino-phenol oxidants. The form of the composition and the state of the components therein can also be affected by temperature, and the composition properties can optionally be described at a specific temperature (e.g., such as at a storage temperature of 5 °C or below, at room temperature (25 °C), or at the temperature for the desired application).

[0076] In some embodiments, the amino-phenol oxidant is present in a "stock solution" composition or "concentrate", wherein the concentrate is configured to be added to a biodiesel or bio-lubricant composition. Adding the amino-phenol oxidant concentrate dilutes it to the working concentration in the biodiesel or bio-lubricant composition. The amino-phenol oxidant concentrate can be a biodiesel or bio-lubricant composition that has not been pre-treated with any second component (e.g., a performance enhancing component), or it can be added to a biodiesel or bio-lubricant composition that has been pre-treated with one or more second components. The amino-phenol oxidant can even be added to a biodiesel or bio-lubricant composition that has been pre-treated with an antioxidant different from the amino-phenol oxidant antioxidant of the present disclosure.

[0077] The stock solution composition of the amino-phenol oxidant can be dissolved in a solvent to a concentration of at least about 0.00001 wt%, at least about 1 wt%, at least about 5 wt%, such as in an amount in the range of about 0.00001 wt% to about 50 wt%, in the range of about 1 wt% to about 50 wt%, or in the range of about 5 wt% to about 50 wt%.

[0078] The concentrate containing the amino-phenol oxidant can be present in the composition with a solvent or combination of solvents. The solvent or solvent combination can be selected such that the amino-phenol oxidant is soluble in the solvent or solvent combination. Useful solvents include any solvent in which the amino-phenol oxidant is soluble or can be stably suspended. In some embodiments, the solvent or solvent combination can be selected from water-soluble or water-miscible solvents, such as glycol-based solvents, and hydrophobic or hydrocarbon solvents, such as aromatic solvents, alkane solvents, or a mixture of both.

[0079] Exemplary glycol solvents include, but are not limited to, C1-C8 glycols, such as ethylene glycol, propylene glycol, diethylene glycol, and triethylene glycol, ethers of such glycols, such as diethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol, triethylene glycol monomethyl ether, liquid polyethylene glycol, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, and low molecular weight polypropylene glycols, etc., and combinations thereof. Commercial solvents such as Butyl Carbitol and ButylCELLOSOLVE can be used TM which mainly contains Butyl CARBITOLTM , which consists mainly of ethylene glycol monobutyl ether and the commercial solvent is available from DOW.

[0080] Other exemplary hydrophobic or hydrocarbon solvents include: heavy aromatic naphtha, toluene, ethylbenzene, isomeric hexane, benzene, xylene, such as o-xylene, p-xylene or m-xylene, and mixtures of two or more thereof.

[0081] In some embodiments, the solvent is selected from ethylene glycol and aromatic naphtha and combinations thereof.

[0082] The concentrate containing amino phenol oxide may also optionally contain one or more additional components, such as additives, which can be advantageously used at working concentrations in biodiesel or biolubricant compositions. These optional additive components can include, for example, dispersants or detergents, demulsifiers, defoamers, etc., as described herein. In the concentrate, one or more optional additives can also be present at high concentrations together with the amino phenol oxide antioxidant such that when the concentrate is diluted, these components are provided at working concentrations (e.g., ppm).

[0083] In some embodiments, the amino phenol oxide antioxidant is used in vegetable oils or animal oils or fat compositions, or in compositions including derivatives thereof. The amino phenol antioxidant can also be present in a food or food composition that also includes vegetable oil or animal oil or fat. In some cases, the amino phenol antioxidant can be directly used in a pure (neat) vegetable oil or animal oil or fat composition. In other cases, the amino phenol antioxidant becomes present in the food or food composition because it is first present in the vegetable oil or animal oil.

[0084] Vegetable oils and fats are typically extracted from seeds or other parts of vegetables and fruits. For example, common vegetable oils include palm oil, soybean oil, rapeseed oil, sesame oil, sunflower oil, grapeseed oil, olive oil, and cottonseed oil. Common animal oils include fish oil and fats from animals such as pigs and chickens. Vegetable oils and fats typically include a mixture of triglycerides. The amino phenol oxide antioxidant can be directly added to any type of vegetable oil or animal oil composition (refined or unrefined) to provide antioxidant activity and prevent oxidation of the oil component therein.

[0085] Vegetable oils can be partially or fully hydrogenated to provide oil derivatives with higher melting points. Hydrogenation of vegetable oils typically involves spraying the oil with hydrogen in the presence of a catalyst at high temperature and pressure. An example of a hydrogenated oil product is vegetable shortening that has solid characteristics at room temperature. The amino phenol oxide antioxidant can be added directly to the oil before hydrogenation or after hydrogenation is carried out.

[0086] Vegetable oils or animal oils containing the disclosed amino-phenol antioxidants can also be used to prepare compositions or articles not intended for ingestion. For example, vegetable oils stabilized with amino-phenol antioxidants can be used to prepare personal care products or cosmetic products, such as soaps, skin products, and fragrances. Vegetable oils containing antioxidants can also be used to manufacture candles and other combustible articles or compositions that can provide heat, light, or odor. Vegetable oil antioxidants can also be used as drying oils, or can be used in varnish or paint compositions. Stabilized vegetable oils can be used to prepare wood treatment compositions and can be used in alkyd resin production. Non-toxic and biodegradable vegetable oils can also be used in electrical insulators and can benefit from amino-phenol antioxidants to improve their stability.

[0087] Vegetable oils can also be used to form biodegradable hydraulic fluids. Hydraulic fluids are commonly used in various machines to transmit power to the moving parts of these machines. Hydraulic fluids are used in various types of heavy equipment, such as for excavation and construction, cargo and human transportation, and military machinery. Examples include, but are not limited to, bulldozers, tractors, excavators, forklifts, cranes, trucks, airplanes, and ships. Suitable hydraulic devices should be able to facilitate power transmission with minimal losses, prevent corrosion of metal surfaces, and lubricate surfaces moving relative to each other. Vegetable oils are typically used with additives to provide the desired properties to the fluid composition.

[0088] The amino-phenol antioxidants can be added to biodiesel compositions, which can be refined or distilled biodiesel compositions, crude biodiesel compositions, or biodiesel compositions having both crude and refined components.

[0089] An amino phenol antioxidant can be added to a biodiesel composition, which is typically prepared by the esterification of animal and / or vegetable oils. For example, some vegetable oils used to prepare biodiesel include palm oil, soybean oil, rapeseed oil, sesame oil, sunflower oil, grapeseed oil, olive oil, and cottonseed oil. Some animal oils used to prepare biodiesel include fish oil and fats from animals such as pigs and chickens. Any one of these oils, fats, or any combination thereof can be subjected to a transesterification process that reacts an oil such as triglyceride with a monohydric alcohol such as methanol, ethanol, propanol, butanol in the presence of a base catalyst to produce fatty acid alkyl esters (FSAE). Most commonly, methanol reacts with the oil to produce fatty acid methyl esters (FAME). During transesterification, the viscosity of the composition decreases because FAME has a lower viscosity compared to the triglyceride starting materials (oils and / or fats). In some cases, crude vegetable oil can be degummed, neutralized, and bleached prior to transesterification to prepare "pure vegetable oil" (SVO). Using SVO as the starting oil material may be desirable because it removes materials such as gums, soaps, and other impurities that could otherwise enter the biodiesel formulation.

[0090] Regarding viscosity, it has been reported that the viscosity values of vegetable oils vary between 27.2 mm2 / s and 53.6 mm2 / s, whereas the viscosity of vegetable oil methyl esters varies between 3.59 mm2 / s and 4.63 mm2 / s (M. Acaroglu and A. Demirbas (2007) Relationships between Viscosity and Density Measurements of Biodiesel Fuels, Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 29:8, 705 - 712, DOI: 10.1080 / 00908310500280827). Crude biodiesel can have a mixture of FAME and unreacted triglycerides and thus can have a viscosity between these two ranges.

[0091] In some embodiments, an amino phenol antioxidant is added to the crude biodiesel composition. This can be particularly useful for preventing oxidation of the crude composition before it can be refined. For example, an amino phenol antioxidant is added to the crude biodiesel composition, which is then stored for a period of time and / or transported. During storage and / or transportation, oxidation of the fatty acid esters formed can be prevented, which in turn facilitates subsequent refining processes.

[0092] During the transesterification process, reaction by-products of FAME, as well as glycerol and residual soap, are formed. As mentioned, unreacted triglycerides can also be present in the crude biodiesel. The crude biodiesel can be distilled to remove glycerol and excess alcohol, and then water can be used to treat the crude biodiesel to remove residual soap. Additionally, the crude biodiesel can then be filtered using a powder such as magnesium silicate to produce a refined (final) biodiesel product. In some modes of practice, an aminophenol antioxidant can be added to the crude biodiesel composition before the crude biodiesel composition is refined. The aminophenol antioxidant can be retained with the FAME during the refining process and thus remains in the purified biodiesel composition.

[0093] Crude and refined biodiesel can contain fully saturated, monounsaturated, diunsaturated, and / or triunsaturated fatty acid methyl esters having 8 to 22 carbon atoms, as described herein, derived from plant sources and / or animal sources. Specific chemicals that can be present in crude and refined biodiesel include methyl octanoate, methyl decanoate, methyl laurate, methyl myristate, methyl lauroleate, methyl myristoleate, methyl palmitoleate, methyl palmitate, methyl stearate (methyl n-octadecanoate), methyl oleate (methyl 9-octadecenoate), methyl vaccenate (methyl 11-octadecenoate), methyl linoleate (methyl 9,12-octadecadienoate), methyl linolenate (methyl 9,12,15-octadecatrienoate), methyl elaidate, methyl arachidate, methyl gadoleate, methyl arachidonate, methyl erucate, and methyl behenate.

[0094] In an embodiment, the major fatty acid methyl esters in the crude biodiesel or refined biodiesel are selected from methyl palmitoleate, methyl palmitate, methyl stearate (methyl n-octadecanoate), methyl oleate (methyl 9-octadecenoate), methyl vaccenate (methyl 11-octadecenoate), methyl linoleate (methyl 9,12-octadecadienoate), methyl linolenate (methyl 9,12,15-octadecatrienoate), methyl elaidate, methyl arachidate, methyl gadoleate, methyl arachidonate, and methyl erucate, which are C16 saturated and partially unsaturated and C18 saturated and partially unsaturated fatty acid methyl esters. "Major" means a fatty acid methyl ester, or more typically a plurality of fatty acid methyl esters, that account for greater than 50 wt% of the total fatty acid methyl esters in the biodiesel composition. In an embodiment, greater than 60 wt%, greater than 70 wt%, greater than 80 wt%, greater than 90 wt%, or greater than 95 wt% of the fatty acid methyl esters in the biodiesel composition are selected from C16 and C18 saturated and partially unsaturated fatty acid methyl esters.

[0095] Biodiesel fuel may optionally be described in terms of iodine value, which reflects the amount of unsaturated fatty acid esters in the composition and the ease of oxidation of the oil when exposed to air. Generally, the iodine value of biodiesel typically ranges from 60 to 150, and more typically from 80 to 135. A higher iodine value indicates that the fatty acid esters have more unsaturated carbon-carbon bonds. The iodine value can be determined using standards such as DIN 53241-1. After a defined storage period, the iodine value can be determined for biodiesel compositions containing the oxidation aminophenol antioxidants of the present disclosure and biodiesel compositions without antioxidants, or can be compared with different antioxidants. In some embodiments, the biodiesel fuel containing the oxidation aminophenol antioxidant has an iodine value of no greater than 125, no greater than 100, or no greater than 75.

[0096] Biodiesel fuel may optionally be described in terms of cetane number, which is a value indicating the fuel combustion rate and compression required for ignition. The cetane number ranges from 15 (longest combustion delay) to 100 (shortest combustion delay). Diesel fuel generally has a cetane number in the range of about 45 to about 65, where biodiesel fuel more specifically has a cetane number in the range of about 48 to about 65. The cetane number can be determined for biodiesel compositions containing the oxidation aminophenol antioxidants of the present disclosure and biodiesel compositions without antioxidants, or can be compared with different antioxidants.

[0097] Biodiesel fuel may optionally be described in terms of energy content such as specific energy (energy per unit mass of biodiesel) or energy density (energy per unit volume of biodiesel). Although biodiesel is denser, it has a lower specific energy than petrodiesel. For example, compared to petrodiesel, biodiesel per unit volume will have about 93% of the energy. Measurement results of energy content are typically expressed in megajoules per kilogram (MJ / kg) (specific mass) or British thermal units per gallon (BTU / gal) (energy density). The exemplary energy density of biodiesel ranges from about 119,550 BTU / gal for B20 to 126,700 BTU / gal for B100 (B100 = 100% biodiesel) (e.g., see: afdc.energy.gov / fuels / properties). The average specific energy of biodiesel is about 37.8 MJ / kg. The energy content can be determined for biodiesel compositions containing the oxidation aminophenol antioxidants of the present disclosure and biodiesel compositions without antioxidants, or compared with different antioxidants.

[0098] Biodiesel fuel can optionally be described in terms of cold flow properties. The cold flow characteristics of biodiesel can be characterized by measurements including one or more of pour point (PP), cloud point (CP), and cold filter plugging point (CFPP). The cloud point can be measured by a standard such as ASTM D2500 (2005), which determines the temperature at which observable crystals form. The lowest temperature at which biodiesel can flow or be pumped is called its pour point (PP). The CFPP tests the highest temperature at which biodiesel can pass through a standard filter. A common method for evaluating the pour point (PP) is according to ASTM D97, and a common method for evaluating the filtration limit via the cold filter plugging point (CFPP) is according to DIN EN 116 or ASTM D6371.

[0099] The FAME content can affect the cold flow characteristics of biodiesel feedstocks. The lower the carbon number and the lower the degree of saturation in the fatty acid chain, the better the cold flow characteristics of the feedstock.

[0100] The PP, CP, and CFPP can be determined for biodiesel compositions containing the oxidation aminophenol antioxidants of the present disclosure and biodiesel compositions without antioxidants, or can be compared with different antioxidants.

[0101] In some embodiments, the biodiesel composition having the oxidation aminophenol antioxidant of the present disclosure has a pour point (PP) value of less than 0 °C, less than -5.0 °C, or less than -10.0 °C. In some embodiments, the biodiesel composition having the oxidation aminophenol antioxidant of the present disclosure has a cloud point (CP) value of less than 0 °C, less than -5.0 °C, or less than -10.0 °C.

[0102] A biodiesel composition having the oxidation aminophenol antioxidant of the biodiesel composition of the present disclosure. In addition, the viscosity can be altered by the amount and molecular weight of the ester-containing polymer used. Measured at 40 °C according to ASTM D445, the kinematic viscosity of the preferred fuel composition of the present invention is in the range of 1 mm2 / s to 10 mm2 / s, more preferably 2 mm2 / s to 5 mm2 / s, and particularly preferably 2.5 mm2 / s to 4.5 mm2 / s.

[0103] Biodiesel fuel can optionally be described in terms of sulfur content. Generally, biodiesel fuel has a low sulfur content, such as about 50 ppm or less, 25 ppm or less, 15 ppm or less, 10 ppm or less, or 5 ppm or less of sulfur. Advantageously, the use of oxidation aminophenol antioxidants does not increase the sulfur content of the biodiesel composition.

[0104] Other measurements of diesel fuel quality include (but are not limited to) energy content, density, lubricity, cold flow characteristics, and sulfur content.

[0105] Biodiesel fuels may optionally be described in terms of flash point. Generally, biodiesel fuels have a flash point in the range of about 100 °C to about 170 °C, such as about 130 °C. The use of the amino-phenol antioxidant should not adversely affect the flash point of the treated biodiesel composition.

[0106] Biodiesel compositions containing the amino-phenol antioxidants of the present disclosure can be used as neat biodiesel or alternatively blended with petrodiesel. Diesel blends containing a portion of biodiesel and a portion of petrodiesel can be formulated to provide certain performance characteristics, depending on how the diesel is intended to be used. In embodiments, the present disclosure provides a blended diesel composition containing an amino-phenol antioxidant, wherein greater than 50 wt%, 60 wt% or more, 70 wt% or more, 80 wt% or more, 90 wt% or more, or 95 wt% or more of the diesel is derived from biodiesel.

[0107] Crude biodiesel and / or refined biodiesel can also be processed, which reduces the unsaturation in the fatty acid moiety of the methyl esters formed.

[0108] Distilled or refined biodiesel results in crude biodiesel that has undergone at least one processing step to remove undesirable components such as excess alcohol, residual glycerol, and other impurities. For example, biodiesel can be obtained as a specific fraction produced during the distillation of crude biodiesel.

[0109] The biodiesel fuels of the present disclosure can optionally be described with reference to boiling point, such as a boiling point in the range of 120 °C to 450 °C or 170 °C to 390 °C. The biodiesel fuel can be derived from middle distillates having low sulfur (e.g., less than 100 ppm, less than 50 ppm, or even less than 10 ppm).

[0110] The amounts of the amino-phenol antioxidants and any other (optional) components in the biodiesel or biolubricant composition can be described in various ways, such as by weight percentage (wt%) of the oxidation aromatic amine in the biodiesel or biolubricant composition, by number of parts of the amount, or by molar amount. When other components are used in the biodiesel or biolubricant composition together with the amino-phenol antioxidants, such compounds can also be described according to the weight ratio in the composition or their relative amounts to each other.

[0111] In some embodiments, the concentration of the amino-phenol antioxidant in the biodiesel fuel is about 1 ppm or greater, 5 ppm or greater, 25 ppm or greater, or 50 ppm or

[0112] greater, and up to about 5000 ppm, up to about 2500 ppm, up to about 1500 ppm, up to about

[0113] from 1000 ppm, up to about 750 ppm, or up to about 500 ppm, or within any of these lower and higher concentrations. For example, the amount of the amino-phenol antioxidant is in the range of from about 1 ppm to 5000 ppm, from about 5 ppm to about 1500 ppm, from about 25 ppm to about 1000 ppm, or from about 50 ppm to about 750 ppm.

[0114] When other additive components are used in the biodiesel composition together with the amino-phenol antioxidant, such compounds may also be described in terms of weight percentage or ppm of the total composition, or in terms of molar concentration, weight ratio, or in terms of the relative amounts of each other in the biodiesel composition.

[0115] Optionally, in addition to the amino-phenol antioxidant, the biodiesel composition may further comprise one or more other additives to provide a fuel having desired specifications and properties. Exemplary optional additives include corrosion inhibitors, dispersants or detergents, demulsifiers, defoamers, cetane improvers, detergents, dyes, metal deactivators, metal passivators, biocides, and flavor or odor masking agents. Any one or more of these additives may be used together with the amino-phenol antioxidant at conventional concentrations known in the art in the biodiesel or bio-lubricant compositions of the present disclosure.

[0116]

[0117] ​Optional corrosion inhibitors that can be added to the biodiesel or bio-lubricant compositions of the present disclosure include compounds such as dodecyl succinate or amide, phosphate esters, alkyl imidazolines, sarcosine, n-butylamine (BA), ethylenediamine (EDA), tert-butylamine (TBA), stearic acid, β-carotene, and propyl gallate. (See, for example, Tabish, A. (2018), Corrosion Behaviour of Biofuel, Petro.Chem.Indus.Intern., 1: 1-19; and Rudnick, L.R. (2003) Lubricant Additives: Chemistry and Applications, "New York, Marcel Dekker, Ch. 5, 137-170). Through its function as an antioxidant, the aminophenol of the present disclosure can indirectly provide corrosion inhibition by minimizing the formation of compounds that might otherwise promote corrosion. Optionally, one or more dispersants can be added to the biodiesel or bio-lubricant compositions of the present disclosure together with the oxidized aminophenol antioxidant. Exemplary dispersants include compounds such as hydrocarbon-substituted succinimides, lecithin surfactants, succinates, pentaerythritol, phenate-salicylate esters, and other surfactant-type compounds. If present in the biodiesel or bio-lubricant composition, the amount of the dispersant can range from about 0.01 wt% to about 10 wt%. See, for example, US20110283603A1, US20150152358A1, US7960322B2, and Rudnick, L.R. (2003) Lubricant Additives: Chemistry and Applications, "New York, Marcel Dekker, Ch. 5, 137-170.

[0118] Optionally, one or more demulsifiers can be added to the biodiesel or bio-lubricant compositions of the present disclosure together with the oxidized aminophenol antioxidant. The demulsifier can facilitate the separation of water and oil in the biodiesel or bio-lubricant composition in contact with water or steam. Exemplary demulsifiers include polyalkylene oxides such as polyethylene oxide, polypropylene oxide, and their copolymers, polyoxyethylene sorbitan esters, anionic surfactants such as alkyl naphthalene sulfonates and alkyl benzene sulfonates, and nonionic alkoxylated alkylphenol resins. If present in the biodiesel or bio-lubricant composition, the amount of the demulsifier can range from about 0.01 wt% to about 10 wt%.

[0119] Optionally, one or more demulsifiers or antifoaming agents can be added to the biodiesel or bio-lubricant compositions of the present disclosure together with the amino-phenol antioxidant. Various types of antifoaming agents are known and can optionally be used to control any form in the compositions of the present disclosure. Examples include, but are not limited to, silicone-based antifoaming agents such as polydimethylsiloxane, halogenated siloxanes, and silicone oils. Other antifoaming agents include polyethers such as polypropylene glycol (PPG) and polyethylene glycol (PEG), alkylated (meth)acrylate polymers, polyethylene ethers, and polyalkoxyamines. If present in the biodiesel or bio-lubricant composition, the amount of the demulsifier can be in the range of about 0.01 wt% to about 5 wt%.

[0120] In some embodiments of the method, the amino-phenol antioxidant inhibits the oxidation of the ester or oil at a level greater than 1.4 times, greater than 1.5 times, greater than 1.6 times, greater than 1.7 times, greater than 1.8 times, greater than 1.9 times, or greater than 2.0 times, up to about 2.2 times, compared to the oxidation level in the absence of the amino-phenol antioxidant.

[0121] In an embodiment, a composition comprising an ester of a fatty acid of plant origin or an oil of plant origin and the amino-phenol antioxidant is a lubricity composition. The lubricity composition can be similar or even identical to the biodiesel fuel composition comprising the amino-phenol. In addition to being usable as a flammable material, fatty acid alkyl esters are known to enhance the lubricity of the compositions containing them. Their function as lubricants may be due to the presence of the alkyl (e.g., methyl) ester chemical group and the unsaturated carbon-carbon bond (C═C) that increases the polarity of the compound, which can promote adhesion to surfaces such as metal surfaces.

[0122] A bio-lubricant composition comprising an alkyl ester fatty acid of plant origin and the amino-phenol antioxidant of the present disclosure can be added to any type of fuel to improve lubricity characteristics. In some embodiments, the bio-lubricant composition is added to fuels such as gasoline, kerosene, aviation fuel, light oil, or alkanol fuel. The lubricant composition can be added to alternative fuels having poor lubricity characteristics, such as dimethyl ether (DME), gas-to-liquid (GTL) fuel derived from natural gas, and coal-to-liquid (CTL) fuel derived from natural gas. A mixture of the alternative fuel and the bio-lubricant composition having an antioxidant can be used to prevent friction and wear in engines using these alternative fuels. Subsequently, this can extend the stability and performance of the carriers using these bio-lubricant materials.

[0123] In an embodiment, the biolubricant composition is mixed with the fuel in an amount of about 0.0001 wt% or more, 0.001 wt% or more, 0.01 wt% or more, or 0.1 wt% or more, and up to about 10 wt%, 5 wt%, or 1 wt%, or within the range of any of these lower and upper limits as endpoints.

[0124] The biolubricant composition can also be used as a lubricant in pure form or can be mixed with a lubricant (e.g., a lubricant derived from petroleum products) at any desired ratio.

[0125] The biolubricant composition of the present disclosure can reduce the friction generated between two mechanical surfaces, such as caused by the movement of at least one of the surfaces relative to the other. Subsequently, the biolubricant composition can extend the life of machines having such moving parts, such as high-pressure ignition type diesel engines.

[0126] Triglycerides from vegetable oils and animal fats can also be used to produce linear alkane (C8 to C18) hydrocarbon compositions, which are specifically used to manufacture aviation fuels. Methods that can be used to prepare these hydrocarbon compositions include hydrodeoxygenation of triglycerides or free fatty acids. Another method is decarboxylation of fatty acids over a heterogeneous noble metal catalyst without using hydrogen. Noble metals such as Pd and Pt have been used to catalyze the decarboxylation of fatty acids and their derivatives. (For example, see, Fu, J. et al., (2010) Catalytic hydrothermal deoxygenation of palmitic acid. Energy Environ Sci. 3: 311 - 317). Decarboxylation of fatty acids over a non-noble metal catalyst without adding hydrogen can also be carried out in the presence of a Ni / C catalyst (for example, see Wu, J. et al., (2016) Catalytic Decarboxylation of Fatty Acids to Aviation Fuels over Nickel Supported on Activated Carbon. Sci Rep 6, 27820).

[0127] In embodiments, the ability of an amino-phenol antioxidant to act as an antioxidant and provide stability to a composition comprising an ester of a fatty acid of plant or animal origin or an oil of plant or animal origin can be described according to an oxidation stability test. A commonly used oxidation stability test is the Rancimat test (e.g., standard test method EN 14112), which measures the conductivity of volatile organic compounds that are formed as degradation products of the oxidation of oxidizable components (such as fatty acid methyl esters) from an oil or oil derivative composition. The test is carried out under conditions that promote oxidation (introduced air and heat), and the conductivity is measured over a period of time until secondary reaction products are presented, which change the conductivity and signal an "induction point". Under the test conditions, the time from the start of the test to the induction point is called the "induction time" or "induction period". For example, as described in the appended examples, the Rancimat test is carried out according to standard test method EN 14112 using an air stream through a 7.5 g sample of an oil or fatty acid methyl ester composition at a temperature of 110 °C and an air flow rate of 10 L / h. The ability of the antioxidant to extend the induction period can be measured and compared to a control (such as an oil composition without an antioxidant or an oil composition containing a comparative antioxidant).

[0128] As reflected in the examples, the induction periods of fatty acid methyl ester (FAME) compositions from various sources are in the range of about 2.87 hours to about 6.71 hours. The difference in induction times can be due to the relative amounts of oxidizable compounds in the FAME composition, or secondary components that promote or impede the oxidation reaction. However, the ability of an antioxidant to extend the induction period can be expressed as a percentage increase in the induction time compared to a control (e.g., a composition without an antioxidant, or a composition with a comparative antioxidant).

[0129] In some embodiments, compared to the induction time without an antioxidant, the amino-phenol antioxidant can extend the induction time by a period greater than 50%, greater than 60%, greater than 65%, greater than 70%, greater than 80%, greater than 90%, greater than 100%, or greater than 110% of the induction time without an antioxidant, and compared to the induction time without an antioxidant, extend up to 275%, up to 250%, up to 225%, up to 200%, up to 175%, up to 160%, up to 150%, up to 140%, up to 130% or up to 125%. For example, relative to a control composition without an antioxidant that originally provides an induction time of 3 hours, an amino-phenol antioxidant of the present disclosure that extends the induction time by 75% will have an induction time of 5.25 hours (i.e., 1.75 × 3 = 5.25).

[0130] The use of the amino-phenol antioxidant typically outperforms other comparative antioxidants, which generally show an induction time that is less than 50% longer than that of an oil composition without an antioxidant. Examples

[0131] Example 1: Synthesis of AO-1 (4-aminophenol-butyl glycidyl ether adduct)

[0132] Referring to the components and their amounts in Table 1, butyl glycidyl ether was added to a 250 mL three-necked round-bottom flask equipped with a temperature probe, a nitrogen inlet, a condenser, and a magnetic stir bar. Then, 4-aminophenol was added to the well-stirred reaction mixture. The resulting suspension was heated to 120 °C under a nitrogen blanket and stirred for 8 hours or until the reaction was complete. As the reaction ended, the suspension converted to a homogeneous dark amber product. The resulting product was characterized by NMR and ESI-MS.

[0133] Table 1

[0134]

[0135]

[0136]

[0137] Example 2: Synthesis of AO-2 (4-aminophenol-2-ethylhexyl glycidyl ether adduct)

[0138] AO-2 was synthesized by replacing butyl glycidyl ether with 2-ethylhexyl glycidyl ether (EHGE) and following the procedure described in Example 1, using amounts of reactants that provided a 4-aminophenol to EHGE molar ratio of 1:2, respectively.

[0139] Example 3: Oxidation stability test of fatty acid methyl esters with various antioxidants

[0140] The oxidative stability of Fatty Acid Methyl Ester Composition #1 (Cargill) was tested by the Rancimat test in the presence of various antioxidants. The Rancimat test measures the conductivity of volatile organic compounds that are formed as degradation products from the oxidation of fatty acid methyl esters. The highly volatile secondary oxidation products, mainly formic acid, are transferred with the air stream to a measuring vessel where they are absorbed into a measuring solution (distilled water). The conductivity is then continuously recorded, where the appearance of organic acids is detected by an increasing conductivity. The time elapsed until the appearance of these secondary reaction products is called the induction time or induction period, which indicates oxidative stability and characterizes the antioxidant properties of fats and oils. The Rancimat test is carried out according to the standard test method EN 14112, which is the most widely used and accepted test for the oxidative stability of biodiesel (B100). Briefly, an air stream is passed through a 7.5 g sample of Fatty Acid Methyl Ester Composition #1 with different antioxidants at concentrations of 500 ppm or 1000 ppm at a temperature of 110 °C and an air flow rate of 10 L / h. The test results and the induction period time (measured in hours) are shown in Table 2.

[0141] Table 2 .

[0142]

[0143]

[0144] Based on this data, FAME (Cargill) has a Rancimat oxidative stability (IP, measured according to EN14112) of 3.98 hours. When the tert-butyl-containing antioxidants L-135 (C7-9-alkyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate) and 2,6-di-tert-butylphenol are used at 1000 ppm, the induction times increase to 4.56 hours and 5.76 hours respectively. When the oxidation aminophenol compounds AO-1 and AO-2 are used at 1000 ppm, a significant increase in the induction time is observed. Furthermore, even when the concentrations of AO-1 and AO-2 are reduced to 500 ppm, they still perform better than the L-135 and 2,6-di-tert-butylphenol antioxidants used at twice the concentration. When used at 1000 ppm, relative to the induction time in the absence of antioxidants, the AO-1 and AO-2 antioxidants extend the induction time by 118% (2.18 times) and 90% (1.90 times) respectively.

[0145] Example 4: Oxidation stability test of fatty acid methyl esters with various antioxidants

[0146] In the presence of In the case of L-135 and AO-2 antioxidants, the oxidation stability of fatty acid methyl ester composition #2 (SUNCOR) was tested using the method described in Example 3. Similar to the method of Example 3, at a temperature of 110 °C and an air flow rate of 10 L / h, an air stream was passed through a 7.5 g sample of fatty acid methyl ester and an antioxidant at a concentration of 1000 ppm.

[0147] Table 3 .

[0148]

[0149] The results of Example 4 show that, using different fatty acid methyl ester compositions, the oxidized aminophenol AO-2 of the present disclosure provides an antioxidant effect greater than that of the comparative antioxidant L-135. When used at 1000 ppm, relative to the induction time in the absence of an antioxidant, the AO-1 antioxidant extended the induction time by 108% (2.08 times).

[0150] Example 5: Oxidation stability test of fatty acid methyl esters with various antioxidants

[0151] In the presence of different concentrations of AO-1 and AO-2 antioxidants, the oxidation stability of fatty acid methyl ester composition #3 (PLACID) was tested using the method described in Example 3. Similar to the method of Example 3, at a temperature of 110 °C and an air flow rate of 10 L / h, an air stream was passed through a 7.5 g sample of fatty acid methyl ester and an antioxidant at concentrations of 250 ppm, 500 ppm, and 1000 ppm.

[0152] Table 4 .

[0153] Antioxidant Concentration (ppm) Induction period (hours) Blank (without AO) 0 4.97 AO-1 1000 9.60 AO-1 500 7.85 AO-2 1000 8.74 AO-2 500 7.28 AO-2 250 6.21

[0154] The results of Example 5 show that the oxidized aminophenols AO-1 and AO-2 of the present disclosure provide acceptable antioxidant effects even at reduced concentrations, specifically as revealed by AO-2 at 250 ppm, which is greater than the comparative antioxidant L-135. When used at 1000 ppm, relative to the induction time in the absence of an antioxidant, the AO-1 and AO-2 antioxidants extended the induction time by 93% (1.93 times) and 76% (1.76 times), respectively. Similarly, lower concentrations (500 ppm, 250 ppm) of AO-1 and AO-2 antioxidants were shown to be effective in extending the induction time.

[0155] Example 6: Oxidation stability test of fatty acid methyl esters with various antioxidants

[0156] In the presence of L-135 (liquid octylated / butylated diphenylamine), The oxidative stability of fatty acid methyl ester composition #4 (REG) was tested for the presence of L-57, 2,6-di-tert-butylphenol, AO-1 and AO-2 antioxidants using the method described in Example 3. Similar to the method of Example 3, an air stream was passed through a 7.5 g sample of fatty acid methyl ester and antioxidants at a concentration of 1000 ppm at a temperature of 110° C. and an air flow of 10 L / h.

[0157] Table 5 .

[0158]

[0159] The results of Example 6 show that using different fatty acid methyl ester compositions, the antioxidant effects provided by the oxidized aminophenols AO-1 and AO-2 of the present disclosure are greater than those of the comparative antioxidants. L-57 and These results also show that the oxidation of aminophenols AO-1 and AO-2 provides superior Excellent antioxidant activity of L-57 antioxidant.

[0160] When used at 1000 ppm, AO-1 and AO-2 antioxidants extended the induction time by 266% (3.66 times) and 215% (3.15 times), respectively, relative to the induction time without antioxidants.

[0161] Example 7: Oxidation stability test of fatty acid methyl esters with various antioxidants at 120 °C

[0162] At a concentration of 1000ppm L-135, The oxidative stability of fatty acid methyl ester composition #1 (Cargill) was tested in the presence of L-57, AO-1 and AO-2 antioxidants using the method described in Example 3, except that the sample temperature was set at 120°C.

[0163] Table 6 .

[0164]

[0165] The results of Example 7 show that at elevated temperatures, the oxidized aminophenol AO-2 of the present disclosure still provides greater antioxidant activity than the comparative antioxidant. L-57, Antioxidant effect of L-135 and 2,6-di-tert-butylphenol: When used at 1000 ppm, AO-2 antioxidant extended the induction time by 94% (1.94 times) relative to the induction time without antioxidant.

Claims

1. A composition, the composition comprising: (ai) an ester of a fatty acid of plant or animal origin, (aii) an oil of plant or animal origin, or both (ai) and (aii); (b) an aminophenol antioxidant of formula I wherein -R 1 、-R 2 、-R 3 、-R 4 and -R 5 are independently selected from -H, -OH, alkyl, aryl, alkylaryl and arylalkyl and -NR 8 R 9 , wherein R 8 and R 9 are independently selected from -H, alkyl, aryl, alkylaryl and arylalkyl, and R 6 / R 7 , or any two adjacent groups of -R 1 、-R 2 、-R 3 、-R 4 and -R 5 form one or more ring structures, wherein at least one of -R 1 、-R 2 、-R 3 、-R 4 and -R 5 is -OH; wherein R 6 and R 7 one or both of which are (i) a carbon-containing group comprising (I) one or more hydroxyl groups, (II) one or more ether groups, or both (I) and (II), which is separated from the N atom by one or more carbon atoms; if R 6 or R 7 is not (i), then it is selected from -H, alkyl, aryl, alkylaryl, and arylalkyl.

2. The composition according to claim 1, the composition being a fuel composition, optionally biodiesel or a bio-lubricant.

3. The composition according to claim 1, the composition being present in a composition for ingestion, wherein the composition for ingestion is optionally a food, and wherein the composition is optionally present in a cooked food product.

4. The composition according to claim 1, the composition being present in a personal care product or a cosmetic product, optionally the personal care product or the cosmetic product being a soap, a skin product or a fragrance.

5. The composition according to claim 1, the composition being present in a varnish or a paint composition.

6. The composition according to claim 1, the composition being present in a composition that is burned for heating, lighting, flavoring or a combination thereof.

7. The composition according to claim 1, the composition being present in an electrical insulator composition.

8. The composition according to claim 1, the composition being present in a hydraulic fluid composition.

9. The composition according to any one of the preceding claims, wherein the ester of the fatty acid of plant or animal origin comprises (1) an ester of a triglyceride of plant or animal origin, (2) an ester of a free fatty acid of plant or animal origin.

10. The composition according to any one of the preceding claims, wherein the ester is (1) a methyl ester of a triglyceride of plant origin, (2) a methyl ester of a free fatty acid of plant origin.

11. The composition according to any one of the preceding claims, wherein the ester of the fatty acid of plant origin is polyunsaturated.

12. The composition according to any one of the preceding claims, wherein the ester of the fatty acid of plant origin comprises a carbon chain having a length in the range of 16 to 18 carbons.

13. The composition according to any one of the preceding claims, wherein the aminophenol antioxidant of formula I is present in the composition in an amount in the range of 100 ppm to 2500 ppm or in an amount in the range of 250 ppm to 1500 ppm.

14. The composition according to any one of the preceding claims, wherein R 6 and R 7 one or both of which are carbon-containing groups having a carbon atom number in the range of 1 to 24, 2 to 23, 2 to 22, 3 to 24 or 4 to 24.

15. The composition according to any one of the preceding claims, wherein -R 3 is -OH.

16. The method according to any one of the preceding claims, wherein the one or more hydroxyl groups are separated from the N atom by two or more carbon atoms, and optionally by two carbon atoms.

17. The composition according to any one of the preceding claims, wherein R 6 and R 7 one or both of which have the formula: -(CR 10 2) q (CHOH)(CH2) z R 11 where R 10 is independently selected from -H and alkyl, where q and z are independently (-) (covalent bond), or an integer in the range of 1 to 12, preferably (-), 1 or 2, and R 11 is selected from C1 to C24 straight-chain, branched-chain or cyclic alkyl, aryl, alkyl-aryl and aryl-alkyl.

18. The composition according to claim 16, wherein R 10 is -H; q is 1; z is (-); and R 11 is C1 to C18 straight-chain, branched-chain or cyclic alkyl, aryl, alkyl-aryl and aryl-alkyl.

19. The composition according to claim 18, wherein the compound is: 4-bis[(2-hydroxyethyl)amino]phenol, 4-bis[(2-hydroxypropyl)amino]phenol, 4-bis[(2-hydroxybutyl)amino]phenol, 4-bis[(2-hydroxypentyl)amino]phenol, 4-bis[(2-hydroxyhexyl)amino]phenol, 4-bis[(2-hydroxy-2-phenyl)amino]phenol, 4-bis[(2-hydroxy-2-phenylethyl)amino]phenol, 4-bis[(2-hydroxyheptyl)amino]phenol, 4-bis[(2-hydroxyoctyl)amino]phenol, 4-bis[(2-hydroxynonyl)amino]phenol, 4-bis[(2-hydroxydecyl)amino]phenol, 4-bis[(2-hydroxyundecyl)amino]phenol, 4-bis[(2-hydroxydodecyl)amino]phenol, 4-bis[(2-hydroxytridecyl)amino]phenol, 4-bis[(2-hydroxytetradecyl)amino]phenol, 4-bis[(2-hydroxypentadecyl)amino]phenol, 4-bis[(2-hydroxyhexadecyl)amino]phenol, 4-bis[(2-hydroxyheptadecyl)amino]phenol, 4-bis[(2-hydroxyoctadecyl)amino]phenol, 4-bis[(2-hydroxyalkenyl)amino]phenol, 4-bis[(2-hydroxynonadecyl)amino]phenol, 4-bis[(2-hydroxyicosyl)amino]phenol, 4-bis[(2-hydroxyhenicosyl)amino]phenol, 4-bis[(2-hydroxydocosyl)amino]phenol and 4-bis[(2-hydroxytricosyl)amino]phenol.

20. The composition according to any one of the preceding claims, wherein R 6 and R 7 in one or both of them have the formula: -(CR 10 2) q (CHOH)(R 12 O) z R 11 , R 10 is independently selected from -H and alkyl, q is (-) (covalent bond) or an integer in the range of 1 to 12, preferably (-), 1 or 2, R 11 is selected from C1 to C24 straight-chain, branched-chain or cyclic alkyl, aryl, alkyl-aryl and aryl-alkyl, and R 12 is independently selected from -(CH2) w -, where w is 1, 2 or 3, and z is an integer in the range of 1 to 5.

21. The composition according to claim 20, wherein R 10 is -H; q is 1; z is 1; w is 1 or 2, and R 11 is C1 to C18 linear, branched or cyclic alkyl, aryl, alkyl-aryl and aryl-alkyl.

22. The composition according to claim 21, wherein the compound is selected from: 4-bis[(3-methoxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-ethoxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-propoxy-2-hydroxy)-propyl)amino]phenol, 4-bis[(3-butoxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-pentyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-hexyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-heptyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-octyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-nonyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-decyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-undecyloxy-2)-hydroxy-propyl)amino]phenol, 4-bis[(3-dodecyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-tridecyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-tetradecyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-pentadecyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-hexadecyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-heptadecyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-octadecyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-alkenyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-nonadecyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-eicosyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-heneicosyloxy-2-hydroxy-propyl)amino]phenol, 4-bis[(3-docosyloxy-2-hydroxy-propyl)amino]phenol, and 4-bis[(3-tricosyloxy-2-hydroxy-propyl)amino]phenol.

23. A composition according to any one of the preceding claims, wherein the composition is characterized by its ability to inhibit the oxidation of oxidizable components in the composition as determined by the induction period, wherein the induction period is measured by the Rancimat test standard test method EN 14112 at a temperature of 110 °C and an air flow of 10 L / h and an antioxidant concentration of 1000 ppm, using an air flow through a 7.5 g sample of the composition, wherein the oxidation aminophenol antioxidant can extend the induction period by a period greater than 50% compared to the induction time in the absence of an antioxidant, or by a period greater than 60%, 70%, 80%, 90%, 100% or 110% compared to the induction time in the absence of an antioxidant, and by a period up to 275%, 250%, 225%, 200%, 175%, 160%, 150%, 140%, 130% or up to 125% compared to the induction time in the absence of an antioxidant.

24. A method for inhibiting the oxidation of esters of fatty acids of plant or animal origin or oils of plant origin in a biobased fuel or lubricant composition, the method comprising: adding an aminophenol antioxidant to a composition comprising (ai) an ester of a fatty acid of plant or animal origin, (aii) an oil of plant or animal origin, or both (ai) and (aii), wherein the aminophenol antioxidant is a compound of formula I wherein -R 1 、-R 2 、-R 3 、-R 4 and -R 5 are independently selected from -H, -OH, alkyl, aryl, alkylaryl and arylalkyl and -NR 8 R 9 , wherein R 8 and R 9 are independently selected from -H, alkyl, aryl, alkylaryl and arylalkyl, and R 6 / R 7 , or any two adjacent groups among -R 1 、-R 2 、-R 3 、-R 4 and -R 5 form one or more ring structures, wherein at least one of -R 1 、-R 2 、-R 3 、-R 4 and -R 5 is -OH; wherein R 6 and R 7 one or both of which is (i) a carbon-containing group comprising one or more hydroxyl groups, said hydroxyl groups being separated from the N atom by one or more carbon atoms; if R 6 or R 7 is not (i), then it is selected from -H, alkyl, aryl, alkylaryl and arylalkyl.

25. The method according to claim 24, wherein the addition forms a composition according to any one of claims 1 to 23.

26. The method according to claim 24 or 25, wherein the aminophenol antioxidant is present in the composition in an amount in the range of 100 ppm to 2500 ppm or in an amount in the range of 250 ppm to 1500 ppm.

27. The method according to claim 24 or 25, wherein the composition is characterized by its ability to inhibit the oxidation of oxidizable components in the composition as determined by the induction period, wherein the induction period is measured by the Rancimat test standard test method EN 14112 at a temperature of 110 °C and an air flow of 10 L / h and an antioxidant concentration of 1000 ppm, using an air flow through a 7.5 g sample of the composition, wherein the oxidation aminophenol antioxidant can extend the induction period by a period greater than 50% compared to the induction time in the absence of an antioxidant, or by a period greater than 60%, 70%, 80%, 90%, 100% or 110% compared to the induction time in the absence of an antioxidant, and by a period up to 275%, 250%, 225%, 200%, 175%, 160%, 150%, 140%, 130% or up to 125% compared to the induction time in the absence of an antioxidant.

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