AU654518B2

AU654518B2 - Multifunctional additives to improve the low-temperature properties of distillate fuels and compositions containing same

Info

Publication number: AU654518B2
Application number: AU91015/91A
Authority: AU
Inventors: David Joseph Baillargeon; Angeline Baird Cardis; Dale Barry Heck; Susan Wilkins Johnson
Original assignee: Mobil Oil Corp
Current assignee: ExxonMobil Oil Corp
Priority date: 1990-12-03
Filing date: 1991-12-02
Publication date: 1994-11-10
Anticipated expiration: 2011-12-02
Also published as: EP0561947A4; WO1992009673A1; EP0561947A1; AU9101591A; JPH06503836A; KR930703420A

Description

MULTIFUNCTIONAL ADDITIVES TO IMPROVE THE

LOW-TEMPERATURE PROPERTIES OF DISTILLATE FUELS

AND COMPOSITIONS CONTAINING SAME

This application is directed to ester and

ester/amide reaction products which are useful for improving the low-temperature properties of distillate fuels; to concentrates and to fuel compositions

containing same.

Traditionally, the low-temperature properties of distillate fuels have been improved by the addition of kerosene, sometimes in very large amounts (5-70 wt %). The kerosene dilutes the wax in the fuel, i.e. lowers the overall weight fraction of wax, and thereby lowers the cloud point, filterability temperature, and pour point simultaneously.

This invention seeks effectively to lower both the cloud point and CFPP (Cold Filter Plugging Point) of distillate fuel without any appreciable dilution of the wax component of the fuel.

The novel esters and ester/amides prepared in accordance with this invention have been found to be surprisingly active wax crystal modifier additives for distillate fuels. Distillate fuel compositions

containing ≤0.1 wt % of such additives demonstrate significantly improved low-temperature flow properties, i.e. lower cloud point and lower CFPP filterability temperature.

Thus an object of this invention is to improve the low-temperature flow properties of distillate fuels. The reaction products of this invention are especially effective as additives in lowering the cloud point of distillate fuels, and thus improve the low-temperature flow properties of such fuels without the use of any light hydrocarbon diluent, such as kerosene. In addition, the filterability properties are improved as demonstrated by lower CFPP temperatures. Thus, the reaction products of this invention demonstrate multifunctional activity in distillate fuels.

The reaction products of this invention are ester or ester/amide products which have core-pendant groups (star-like) structures derives from the reaction of an anhydride - or carboxylic acid - containing "core" - former with, as "pendant group" - former : (1) an amino alcohol, suitably the product of reaching an amine and an epoxide or (2) a combination of an amino alcohol and a secondary amine. Preferred anhydrides include pyromellitic dianhydride (PMDA) and benzophenone tetracarboxylic dianhydride (BTDA).

More specifically, this invention provides a reaction product preparable by reacting :

i) a compound comprising a hydrocarbyl

anhydride group, or a hydrocarbyl carboxylic acid group, the latter having at least two carboxylic acid groups; with

ii) an aminoalcohol; and

iii) optionally, a secondary amine at a

temperature from 85° to 250°C and a pressure from ambient to greater than autogenous to obtain the desired ester or ester/amide reaction product.

Component (i) may include a mixture of such compounds. Component (ii) may include a mixture of aminoalcohols and component (iii), where present, may include a mixture of secondary amines; preferably it is the same secondary amine, or mixture of secondary amines, suitably fatty amines, used to prepare (ii) in accordance with the reaction :

wherein R₁, R₂ and R₃ are herein defined. The reaction products of this invention have core-pendant group (star-like) structures. These reaction products are obtained by combining the core structure and the pendant group(s) in differing ratios using standard techniques for esterification/

amidification. These reaction products which are highly effective as wax crystal modifiers in lowering cloud point are generally characterized by the

following structural features:

(a) a compact "core" which forces close proximity of the pendant groups (pairs of adjacent carboxyl groups where the pendant groups are attached are generally separated by four or fewer atoms);

(b) a pendant group containing a high density of

paraffin chains; and

(c) a pendant group structured in such a way as to allow facile parallel orientation of the attached paraffin chains.

Suitable core structures contain two or more reactive carboxyl groups (anhydrides, acids, or acid equivalents). These structures include, but are not limited to, aromatic, alicyclic, aralkyl, alkaryl, and alkyl hydrocarbons, as well as their corresponding heteroatom-containing analogues.

The reaction products of this invention are derived from "core" and "pendant group" precursors, and a range of reactant stoichiometries may be used.

However, each reaction product requires one "core" derivatized with at least one aminoalcohol "pendant group"; any additional pendant groups may be either aminoalcohols or amines and may be added up to the limit of available reactive carboxyl groups in the core structure.

Reaction products of this invention may be grouped into categories based on distinct structural and compositional differences, described below. Catecrory A: Aromatic "Core" (TABLE 2)

The preferred aminoalcohol, Entry 1, used in the synthesis of the reaction product of this invention, has low cloud point and CFPP activity by itself.

Successful additives may be prepared from aromatic cores which are difunctional (e.g. phthalic anhydride, Entry 7), trifunctional (e.g trimesic acid, Entries 3-6; trimellitic anhydride. Entries 14-16), or

tetrafunctional (e.g. tetrahydrofuran tetracarboxylic dianhydride, Entry 11). The requirement that one pendant group must be an appropriate aminoalcohol is demonstrated by the amide analogues of PMDA

(pyromellitic dianhydride; Entries 2, 12) and BTDA (benzophenonetetracarboxylic dianhydride; Entry 13); such analogues prepared without any aminoalcohol do not attain high cloud point activity. The requirement that the core functional groups allow the pendant groups to approach one another (i.e. carboxyl groups separated by no more that four atoms) is best demonstrated by the dicarboxyl benzene series (Entries 7-9) and by

2,6-naphthalene dicarboxylic acid (Entry 10). As the product ester groups move further apart, from

two-carbon separation (Entry 7) to three-carbon

separation (Entry 8) to four- and six- carbon

separation (Entries 9 and 10), the additive's cloud point activity falls from high activity to low

activity.

A typical synthesis is illustrated by the

preparation of the trimesate material (Entry 3) in EXAMPLE 25.

Category B: Bicyclic and Alicyclic "Cores" (TABLE 3)

Successful additives may be prepared from

non-aromatic but relatively structurally rigid cores, such as bicyclics or alicyclics. Bicyclic cores may be difunctional (e.g. norbornene dicarboxylic anhydride,

Entry 17; camphoric acid, Entry 19), or tetrafunctional (e.g bicyclooctene tetracarboxylic dianhydride, Entry 18). An example of a suitable alicyclic core is cyclohexane dicarboxylic anhydride (Entry 20).

A typical synthesis is illustrated by the

preparation of the norbornene diester (Entry 17) in EXAMPLE 26.

Category C: Alkyl "Cores" (TABLE 3)

Successful additives may be prepared from

non-rigid cores if the density of reactive groups is sufficiently high, i.e. if the core molecule is sufficiently small. For example, additives with good cloud point activity were derived from butyl citrate (Entry 21), and from maleic anhydride (Entry 22). By comparison, additives derived from large non-rigid alkyl cores such as dimer acid (Hystrene 3695, Entry 23) and trimer acid (Hystrene 5460, 60:40 mixture of trimer:dimer acids, Entry 24) offer little substantial cloud point activity.

A typical synthesis is illustrated by the

preparation of the maleate ester (Entry 22) in EXAMPLE 27.

Category D: Multifunctional. Post-Reacted Additives

(TABLE 4)

Multifunctional additives may be prepared from the cloud point additives of this invention, and may have advantages as ashless dispersants, detergents, antirust agents, antiwear agents, etc. Multifunctionality may be introduced into the core/pendant group additives whenever a suitably reactive group is available for post-reaction with a secondary chemical agent.

In one approach, for example, judicious choice of core/pendant group stoichiometry may leave residual acid and/or anhydride groups available for

post-reaction. This strategy was demonstrated with PMDA and BTDA derivatives (Entries 25-30, and 33-34) where only half of the available carboxyl groups were esterified with the aminoalcohol from Armeen

2HT/Vikolox 18, i.e. di(hydrogenated tallow) amine/1,2-epoxy-C₁₈ alkane. Such materials were then post-reacted with (a) mono-capped polypropylene glycol (e.g. UCON LB-1145, average MW=2200, Entry 25-26), (b) amino-polyethers (e.g. Jeffamine M-600, mono-capped amine-terminated polypropylene oxide, MW=600, Entries 27-28; Surfonamine MNPA-380 amino polyether-capped nonylphenol, Entries 29-30), and (c) polyethyleneamine (e.g. E-100, Entries 33-34). Entries 31-32 again demonstrate the low additive activities attained when the aminoalcohol component of the composition (in this case the adduct of Armeen 2HT/Vikolox 18) is absent.

In another approach, the secondary reactive functionality is chosen so as to be unreactive in the initial esterification process used to prepare the cloud point additive. For example (Entries 35-36), maleic anhydride was esterified with the Armeen

2HT/Vikolox 18 aminoalcohol, and the remaining

activated olefin was post-reacted via addition of the polyethyleneamine TEPA (tetraethylenepentaamine).

Preferred classes of reaction product of this invention have core-pendant group (star-like)

structures derived from pyromellitic dianhydride (PMDA) or benzophenone tetracarboxylic diahydride (BTDA) or acid equivalents. For example, a general structure for the PMDA/aminoalcohol ester is as follows:

A general structure for the

PMDA/aminoalcohol/amine ester/amide is as follows:

A general structure for the PMDA/mixed aminoalcohol ester is as follows:

A general structure for the PMDA/aminoetheralcohol ester is as follows:

A general structure for the

PMDA/aminoetheralcohol/amine ester/amide is as follows:

Where: x = y + z = 0.5-4

a = 1-3

R₁, R₃ = C₈-C₅₀ linear hydrocarbyl groups, either saturated or unsaturated.

R₂ = R₂, C₁-C₁₀₀ hydrocarbyl

R₄ = H, C₁-C₅₀ hydrocarbyl

Likewise, mutatic mutandis, for the reaction products obtained from BTDA.

Any suitable olefin oxide may be used. Epoxides are especially preferred. Included are such oxides as ethylene oxide, 1,2-epoxybutane, 1,2-epoxydecane,

1,2-epoxydodecane,

1,2-epoxytetradecane, 1,2-epoxypentadecane,

1,2-epoxyhexadecane, 1,2-epoxyheptadecane,

l,2-epoxyoctadecane, 1,2-epoxyeicosane and the like and mixtures thereof and mixtures of C₂₀ to C₂₄ alpha olefin epoxides, mixtures of C₂₄ to C₂₈ alpha olefin epoxides and the like.

Suitable amines, as indicated above, are secondary amines with at least one long-chain hydrocarbyl group, e.g. C₈ to about C₅₀. Highly useful secondary amines include but are not limited to di(hydrogenated tallow) amine, ditallow amine, dioctadecylamine,

methyloctadecylamine and the like. In this invention, stoichiometries of amine to epoxide were chosen such that one amine reacted with each available epoxide functional group. Other stoichiometries where the amine is used in lower molar proportions may also be used.

The reactions can be carried out under widely varying conditions which are not believed to be critical. The reaction temperatures can vary from about 100 to 225°C, preferably 120 to 180ºC, under ambient or autogenous pressure. However slightly higher pressures may be used if desired. The

temperatures chosen will depend upon for the most part on the particular reactants and on whether or not a solvent is used. Solvents used will typically be hydrocarbon solvents such as xylene, but any non-polar, unreactive solvent can be used including benzene and toluene and/or mixtures thereof.

Molar ratios, less than molar ratios or more than molar ratios of the reactants can be used.

Preferentially a molar ratio of 1:1 to about 8:1 of epoxide to amine is chosen.

The times for the reactions are also not believed to be critical. The process is generally carried out in from about one to twenty-four hours or more.

In general, the reaction products of the present invention may be employed in any amount effective for imparting the desired degree of activity to improve the low temperature characteristics of distillate fuels. In many applications the products are effectively employed in amounts from about 0.001% to about 10% by weight and preferably from less than 0.01% to about 5% of the total weight of the composition.

These additives may be used in conjunction with other known low-temperature fuel additives

(dispersants, etc.) being used for their intended purpose. The fuels contemplated are liquid hydrocarbon combustion fuels, including the distillate fuels and fuel oils. Accordingly, the fuel oils that may be improved in accordance with the present invention are hydrocarbon fractions having an initial boiling point of at least about 250ºF and an end-boiling point no higher than about 750°F and boiling substantially continuously throughout their distillation range. Such fuel oils are generally known as distillate fuel oils. It is to be understood, however, that this term is not restricted to straight run distillate fractions. The distillate fuel oils can be straight run distillate fuel oils, catalytically or thermally cracked

(including hydrocracked) distillate fuel oils, or mixtures of straight run distillate fuel oils, naphthas and the like, with cracked distillate stocks.

Moreover, such fuel oils can be treated in accordance with well-known commercial methods, such as, acid or caustic treatment, hydrogenation, solvent refining, clay treatment, etc.

The distillate fuel oils are characterized by their relatively low viscosities, pour points, and the like. The principal property which characterizes the contemplated hydrocarbons, however, is the distillation range. As mentioned hereinbefore, this range will lie between about 250ºF and about 750°F. Obviously, the distillation range of each individual fuel oil will cover a narrower boiling range falling, nevertheless, within the above-specified limits. Likewise, each fuel oil will boil substantially continuously throughout its distillation range.

Contemplated among the fuel oils are Nos. 1, 2 and 3 fuel oils used in heating and as diesel fuel oils, and the jet combustion fuels. The domestic fuel oils generally conform to the specification set forth in

A.S.T.M. Specifications D396-48T. Specifications for diesel fuels are defined in A.S.T.M. Specification D975-48T, Typical jet fuels are defined in Military Specification MIL-F-5624B.

The following Examples illustrate the invention.

EXAMPLE 1

Preparation of Additive 1

Di(hydrogenated tallow) amine (59.8 g, 0.12 mol; e.g. Armeen 2HT from Akzo Chemie), and

1,2-epoxyoctadecane (32.2 g, 0.12 mol; e.g. Vikolox 18 from Viking Chemical) were combined and heated at 160ºC for 16 hours. Pyromellitic dianhydride (6.54 g, 0.03 mol; e.g. PMDA from Allco Chemical Corp.), and xylene (approx. 30 ml) were added and heated at reflux

(160-200°C) with azeotropic removal of water for 24 hours. Volatiles were then removed from the reaction medium at 190-200°C, and the reaction mixture was hot filtered to give 94.6 g of the final product as a low melting solid.

EXAMPLE 2

Preparation of Additive 2

According to the procedure used for Example 1

(above), di(hydrogenated tallow) amine (45.0 g, 0.09 mol), and 1,2-epoxyoctadecane (30.2 g, 0.112 mol) were first combined. Pyromellitic dianhydride (9.82 g, 0.045 mol) was then added, and allowed to react in the second step of the sequence. The final product (72.6 g) was obtained as a low-melting solid.

EXAMPLE 3

Preparation of Additive 3

According to the procedure used for Example 1 (above), di(hydrogenated tallow) amine (74.9 g, 0.15 mol), and 1,2-epoxyoctadecane (20.1 g, 0.075 mol) were first combined. Pyromellitic dianhydride (8.18 g, 0.0375 mol) was then added, and allowed to react in the second step of the sequence. The final product (99.4 g) was obtained as a low-melting solid.

EXAMPLE 4

Preparation of Additive 4

According to the procedure used for Example 1

(above), di(hydrogenated tallow) amine (74.9 g, 0.15 mol), and 1,2-epoxyoctadecane (20.1 g, 0.075 mol) were first combined. Pyromellitic dianhydride (8.18 g, 0.0375 mol) was then added, and allowed to react in the second step of the sequence. The final product (99.4 g) was obtained as a low-melting solid.

EXAMPLE 5

Preparation of Additive 5

According to the procedure used for Example 1 (above), di(hydrogenated tallow) amine (62.4 g, 0.125 mol), and 1,2-epoxyoctadecane (21.0 g, 0.0781 mol) were first combined. Pyromellitic dianhydride (13.6 g, 0.0625 mol) was then added, and allowed to react in the second step of the sequence. The final product (85.5 g) was obtained as a low-melting solid.

EXAMPLE 6

Preparation of Additive 6

According to the procedure used for Example 1 (above), ditallow amine (49.8 g, 0.10 mol); e.g. Armeen 2T from Akzo Chemie), and 1,2-epoxyoctadecane (28.2 g, 0.105 mol; e.g. Vikolox 18 from Viking Chemical) were first combined. Pyromellitic dianhydride (5.45 g, 0.025 mol) was then added, and allowed to react in the second step of the sequence. The final product (84.1 g) was obtained as a low-melting solid. EXAMPLE 7

Preparation of Additive 7

According to the procedure used for Example 1 (above), ditallow amine (49.8 g, 0.10 mol), and

1,2-epoxyoctadecane (33.6 g, 0.125 mol) were first combined. Pyromellitic dianhydride (7.27 g, 0.033 mol) was then added, and allowed to react in the second step of the sequence. The final product (81.4 g) was obtained as a low-melting solid. EXAMPLE 8

Preparation of Additive 8

1,2-epoxyoctadecane (33.6 g, 0.125 mol) were first combined. Pyromellitic dianhydride (10.9 g, 0.050 mol) was then added, and allowed to react in the second step of the sequence. The final product (83.3 g) was obtained as a partly solidified solid.

EXAMPLE 9

Preparation of Additive 9

According to the procedure used for Example 1 (above), di(hydrogenated tallow) amine (40.0 g, 0.080 mol), and 1,2-epoxyeicosane (28.7 g, 0.088 mol; e.g. Vikolox 20 from Viking Chemical) were combined at

220°C. Pyromellitic dianhydride (9.60 g, 0.044 mol) was then added, and allowed to react in the second step of the sequence. The final product (69.8 g) was

obtained as a low-melting solid.

EXAMPLE 10

Preparation of Additive 10

According to the procedure used for Example 1

(above), di(hydrogenated tallow) amine (40.0 g, 0.080 mol), and a mixture of C₂₀-C₂₄ alpha olefin epoxides (30.4 g, 0.088 mol; e.g. Vikolox 20-24 from Viking Chemical) were combined at 220°C. Pyromellitic dianhydride (9.60 g, 0.044 mol) was then added, and allowed to react in the second step of the sequence. The final product (70.9 g) was obtained as a

low-melting solid.

EXAMPLE 11

Preparation of Additive 11

According to the procedure used for Example 1 (above), di(hydrogenated tallow) amine (35.0 g, 0.070 mol), and a mixture of C₂₄-C₂₈ alpha olefin epoxides (33.7 g, 0.077 mol; e.g. Vikolox 24-28 from Viking Chemical) were combined at 220ºC. Pyromellitic dianhydride (8.40 g, 0.0385 mol) was then added, and allowed to react in the second step of the sequence. The final product (69.0 g) was obtained as a

low-melting solid.

EXAMPLE 12

Preparation of Additive 12

Di(hydrogenated tallow) amine (50.0 g, 0.10 mol), and 1,2-epoxyoctadecane (33.6 g, 0.125 mol) were combined and heated at 150°C for 16 hours. To the cooled reaction mixture was added potassium t-butoxide (0.56 g, 0.005 mol), and 1,2-epoxybutane (13.5 g, 0.187 mol). The mixture was heated to 105-115°C for 20 hours, to 150°C for 1 hour, followed by removal of all volatiles at 150°C. Pyromellitic dianhydride (6.00 g, 0.0275 mol), and xylene (approx. 50 ml) were added and heated at reflux (180-190ºC) with azeotropic removal of water for 6 hours. Volatiles were then removed from the reaction medium at 180-190°C, and the reaction mixture was hot filtered to give 83.5 g of the final product as a low-melting solid. EXAMPLE 13

Preparation of Additive 13

Di(hydrogenated tallow) amine (30.0 g, 0.060 mol), and 1,2-epoxyoctadecane (16.1 g, 0.060 mol) were combined and heated at 150°C for 24 hours. To the cooled reaction mixture was added potassium t-butoxide (0.17 g, 0.0015 mol), and 1,2-epoxybutane (5.41 g, 0.075 mol). The mixture was heated to 105-115°C for 20 hours, followed by removal of all volatiles at 150°C. Pyromellitic dianhydride (7.20 g, 0.033 mol),

di(hydrogenated tallow) amine (30.0 g, 0.060 mol), and xylene (approx. 50 ml) were added and heated at reflux (180-190°C) with azeotropic removal of water for 24 hours. Volatiles were then removed from the reaction medium at 180-190°C, and the reaction mixture was hot filtered to give 76.2 g of the final product as a low-melting solid.

EXAMPLE 14

Preparation of Additive 14

Di(hydrogenated tallow) amine (60.0 g, 0.12 mol), and 1,2-epoxyoctadecane (20.1 g, 0.075 mol) were

combined and heated at 150°C for 24 hours. The

reaction mixture (above) and 1,2-epoxybutane (13.0 g, 0.180 mol), was heated in a sealed glass pressure bottle at 170-190°C for 7 hours, under autogenous pressure. Volatiles were removed at 150ºC/atm.

pressure. To this was added pyromellitic dianhydride (7.20 g, 0.033 mol), and xylene (approx. 50 ml)

followed by heating at reflux (180-190°C) with

azeotropic removal of water for 24 hours. Volatiles were then removed from the reaction medium at

180-190ºC, and the reaction mixture was hot filtered to give 78.4 g of the final product as a low-melting solid. EXAMPLE 15

Preparation of Additive 15

Di(hydrogenated tallow) amine (50.0 g, 0.10 mol; e.g. Armeen 2HT from Akzo Chemie), and 1,2-epoxyoctadecane (33.6 g, 0.125 mol; e.g. Vikolox 18 from Viking

Chemical) were combined and heated at 160ºC for 24 hours. Benzophenone tetracarboxylic dianhydride (8.86 g, 0.0275 mol; e.g. BTDA from Allco Chemical Corp.), and xylene (approx. 50 ml) were added and heated at reflux (180-220°C) with azeotropic removal of water for 24 hours. Volatiles were then removed from the

reaction medium at 180-220°C, and the reaction mixture was hot filtered to give 71.9 g of the final product as a low-melting solid. EXAMPLE 16

Preparation of Additive 16

According to the procedure used for Example 15 (above), di(hydrogenated tallow) amine (50.0 g, 0.10 mol), and 1,2-epoxyoctadecane (33.6 g, 0.125 mol) were first combined. Benzophenone tetracarboxylic

dianhydride (10.7 g, 0.0333 mol) was then added, and allowed to react in the second step of the sequence. The final product (86.4 g) was obtained as a

low-melting solid. EXAMPLE 17

Preparation of Additive 17

dianhydride (16.1 g, 0.050 mol) was then added, and allowed to react in the second step of the sequence. The final product (87.2 g) was obtained as a

low-melting solid. EXAMPLE 18

Preparation of Additive 18

According to the procedure used for Example 15 (above), di(hydrogenated tallow) amine (62.4 g, 0.125 mol), and 1,2-epoxyoctadecane (21.0 g, 0.078 mol) were first combined. Benzophenone tetracarboxylic

dianhydride (11.1 g, 0.0343 mol) was then added, and allowed to react in the second step of the sequence. The final product (86.6 g) was obtained as a

low-melting solid.

EXAMPLE 19

Preparation of Additive 19

dianhydride (14.8 g, 0.0458 mol) was then added, and allowed to react in the second step of the sequence. The final product (89.8 g) was obtained as a

low-melting solid.

EXAMPLE 20

Preparation of Additive 20

According to the procedure used for Example 15 (above), 4 g, 0.125 mol), and 1,2-epoxyoctadecane (21.0 g, 0.078 mol) were first combined. Benzophenone tetracarboxylic dianhydride (22.2 g, 0.0687 mol) was then added, and allowed to react in the second step of the sequence. The final product (95.2 g) was obtained as a low-melting solid. EXAMPLE 21

Preparation of Additive 21

According to the procedure used for Example 15 (above), ditallow amine (49.8 g, 0.10 mol), e.g. Armeen 2T from Akzo Chemie), and 1,2-epoxyoctadecane (33.6 g, 0.125 mol) were first combined. Benzophenone tetracarboxylic dianhydride (8.86 g, 0.0275 mol) was then added, and allowed to react in the second step of the sequence. The final product (81.8 g) was obtained as a low-melting solid. EXAMPLE 22

Preparation of Additive 22

According to the procedure used for Example 15 (above), di (hydrogenated tallow) amine (40.0 g, 0.080 mol), and 1,2-epoxyeicosane (28.7 g, 0.088 mol); e.g. Vikolox 20 from Viking Chemical) were combined at

220°C. Benzophenone tetracarboxylic dianhydride (14.2 g, 0.044 mol) was then added, and allowed to react in the second step of the sequence. The final product (71.2 g) was obtained as a low-melting solid. EXAMPLE 23

Preparation of Additive 23

According to the procedure used for Example 15 (above), di (hydrogenated tallow) amine (40.0 g, 0.080 mol), and a mixture of C₂₀-C₂₄ alpha olefin epoxides (30.4 g, 0.088 mol ; e.g. Vikolox 20-24 from Viking Chemical) were combined at 220°C. Benzophenone tetracarboxylic dianhydride (14.2 g, 0.044 mol) was then added, and allowed to react in the second step of the sequence. The final product (75.1 g) was obtained as a low-melting solid.

EXAMPLE 24

Preparation of Additive 24

According to the procedure used for Example 15 (above), di (hydrogenated tallow) amine (35.0 g, 0.070 mol), and a mixture of C₂₄-C₂₈ alpha olefin epoxides (33.7 g, 0.077 mol; e.g. Vikolox 24-28 from Viking Chemical) were combined at 220°C. Benzophenone tetracarboxylic dianhydride (12.4 g, 0.0385 mol) was then added, and allowed to react in the second step of the sequence. The final product (74.2 g) was obtained as a low-melting solid.

EXAMPLE 25

Preparation of Additive Entry 3 Di(hydrogenated tallow) amine (50.0 g, 0.10 mol; e.g. Armeen 2HT from Akzo Chemie), and

1,2-epoxyoctadecane (33.6 g, 0.125 mol; e.g. Vikolox 18 from Viking Chemical) were combined and heated at 160ºC for 17 hours. Trimesic acid (7.71 g, 0.037 mol; e.g. from Amoco Chemical Co.), and xylene (approx. 60 ml) were added and heated at reflux (180-240°C) with azeotropic removal of water for 8 hours. Volatiles were then removed from the reaction medium at

190-200ºC, and the reaction mixture was hot filtered to give the final product.

EXAMPLE 26

Preparation of Additive Entry 17

Di(hydrogenated tallow) amine (50.0 g, 0.10 mol; e.g. Armeen 2HT from Akzo Chemie), and

1,2-epoxyoctadecane (33.6 g, 0.125 mol; e.g. Vikolox 18 from Viking Chemical) were combined and heated at 160°C for 17 hours. Norborene dicarboxylic anhydride (9.03 g, 0.055 mol; e.g. from Aldrich Chemical Co.), and xylene (approx. 60 ml) were added and heated at reflux (180-250°C) with azeotropic removal of water for 8 hours. Volatiles were then removed from the reaction medium at 190-200°C, and the reaction mixture was hot filtered to give the final product.

EXAMPLE 27

Preparation of Additive Entry 22

Chemical) were combined and heated at 190°C for 19 hours. Maleic anhydride (5.88 g, 0.060 mol; e.g. from Aldrich Chemical Co.), and xylene (approx. 60 ml) were added and heated at reflux (185-190°C) with azeotropic removal of water for 22 hours. Volatiles were then removed from the reaction medium at 190°C, and the reaction mixture was hot filtered to give 81.1 g of the final product.

EXAMPLE 28

Preparation of Additive Entry 29 Di(hydrogenated tallow) amine (50.0 g, 0.10 mol; e.g. Armeen 2HT from Akzo Chemie), and 1,2-epoxyoctadecane (33.6 g, 0.125 mol; e.g. Vikolox 18 from Viking

Chemical) were combined and heated at 170 °C for 22 hours. Benzophenone tetracarboxylic dianhydride (17.7 g, 0.055 mol; e.g. BTDA from Allco Chemical Corp.), and xylene (approx. 60 ml) were added and heated at reflux (185-190°C) with azeotropic removal of water for 4.5 hours. Jeffamine M-600 (31.5 g, 0.0525 mol; e.g. a mono-capped amine-terminated polypropylene oxide, from Akzo Chemie) was added and heated at 180°C for 19 hr with azeotropic removal of water. Volatiles were then removed from the reaction medium at 180°C, and the reaction mixture was hot filtered to give 112.7 g of the final product.

Preparation of Additive Concentrate

A concentrate solution of 100 ml total volume was prepared by dissolving 10 g of additive in mixed xylenes solvent. Any insoluble particulates in the additive concentrate were removed by filtration before use. Generally speaking however, each 100 ml of concentrate solution may contain from about 1 to about 50 grams of the additive product of reaction. Test Fuel Characteristics

FUEL A:

API Gravity 35.5

Cloud Point (°F)

Auto CP 15

Herzog 16.4

Pour Point (°F) 10

CFPP, (°F) 9

FUEL B:

API Gravity 34.1

Cloud Point (°F)

Auto CP 22

Herzog 23.4

CFPP, (°F) 16

Pour Point (°F) 0

Test Procedures

The cloud point of the additized distillate fuel was determined using two procedures: (a) an automatic cloud point test based on the commercially available Herzog cloud point tester; test cooling rate is approximately 1°C/min. Results of this test protocol correlate well with ASTM D2500 methods. The test designation (below) is "HERZOG." (b)an automatic cloud point test based on the equipment /procedure detailed in U.S. 4,601,303; the test designation (below) is AUTO CP.

The low-temperature filterability was determined using the Cold Filter Plugging Point (CFPP) test. This test procedure is described in "Journal of the

Institute of Petroleum," Volume 52, Number 510, June 1966, pp. 173-185.

Test results may be found in the TABLE 1 below. TABLE 1

ADDITIVE EFFECTS ON THE CLOUD POINT AND FILTERABILITY

(CPFF) OF DISTILLATE FUEL (ADDITIVE CONCENTRATION = 0.1WT%)

Improvement in Performance Temperature (°F)

Diesel Fuel A Diesel Fuel B

Cloud Point Cloud Point

Additive (Auto CP) (Herzog) CFPP (Auto CP) (Herzog) CFPP

(Example)

1 2 0.7 7 8.5 7.2 7

2 3 2.5 7 8.5 7.8 2

3 3 1.8 7 9.5 7.9 9

4 3 2.9 6 8 7.6 6

5 4 3.8 4 7 7 6

6 3 1.5 7 9.5 7.4 7

7 3 2.2 4 8.5 7.4 4

8 3 2.4 2 8.5 7.2 2

9 3 1.8 6 9 - - - 15

10 2 1.4 6 8 9.9 13

11 1 - - - 4 7 - - - 11

12 1 1.1 4 8.5 7.2 7

13 2 1.3 0 7.5 6.9 2

14 - - - 1.8 8 - - - 7.2 11

Improvement in Performance Temperature (°F) Diesel Fuel A Diesel Fuel B

Cloud Point Cloud Point

Additive (Auto CP) (Herzog) CFPP (Auto CP) (Herzog) CFPP

(Example)

15 3 1.3 3 7.5 6.1 2

16 4 2.8 6 7 6.3 7

17 3 3.7 4 9 7.9 15

18 3 2.5 6 9 7.6 4

19 4 2.9 6 8 7.4 4

20 3 3.6 2 6 5.8 4

21 3 3.4 6 6 5.8 2

22 2 1.6 6 8 - - - 13

23 1 0.7 6 8 9 13

24 1 - - - 6 7 - - - 11

Preparation of Additive Concentrate (EXAMPLES 25 to 28)

A concentrate solution of 100 ml total volume was prepared by dissolving 10 g of reaction product in

mixed xylenes solvent. Any insoluble particulates in the additive concentrate were removed by filtration

before use.

Test Fuels

Two test fuels were used for the screening of

additive activity: FUEL A:

API Gravity 34.1

Cloud Point (°F) 23.4

CFPP (°F) 16

Pour Point (°F) 0

Distillation (°F; D 86)

IBP 319

10% 414

50% 514

90% 628

FBP 689

FUEL B:

API Gravity 31.5

Cloud Point (°F) 21.4

CFPP (°F) 14

Pour Point (°F) 10

Distillation (°F; D 86)

IBP 340

10% 439

50% 534

90% 640

FBP 693

Test Procedures

The cloud point of the additized distillate fuel was determined using an automatic cloud point test based on the commercially available Herzog cloud point tester; test cooling rate is approximately 1°C/min. Results of this test protocol correlate well with ASTM D2500 methods. The test designation (below) is

"HERZOG."

Institute of Petroleum," Volume 52, Number 510, June 1966, pp. 173-185.

Test results may be found in TABLES 2-4 below. The products of this invention represent a significant new generation of wax crystal modifier additives which are dramatically more effective than many previously known additives. They represent a viable alternative to the use of kerosene in improving diesel fuel

low-temperature performance. TABLE 2

Core/Pendant Group Structures

Category A: Aromatic, Heterocyclic Cores

Performance

Improvement (F) :

Mole Cloud Point

Entry Pendant Group(s) Core Ratio (HERZOG) CFPP

Fuel A; 1000 Km Additive

1 Armeen 2HT/Vikolox 18 1/1.25 2.2 -2 2 Armeen 2HT PMDA 4/1 2.5 0 3 Armeen 2HT/Vikolox 18 Trimesic Acid 3/3.75/1.1 5.2 2 4 Armeen 2HT/Vikolox 18 Trimesic Acid 3/2/1 4.7 2 5 Armeen 2HT/Vikolox 18 Trimesic Acid 2/2/1 4.7 2 6 Armeen 2HT/Vikolox 18 Trimesic Acid 2/1/1 4.5 6 7 Armeen 2HT/Vikolox 18 Phthalic Anhy 2/2.5/1.1 5.6 0 8 Armeen 2HT/Vikolox 18 Isophthalic Acid 2/2.5/1 3.4 2 9 Armeen 2HT/Vikolox 18 Terephthalic Acid 2/2.5/1 3.1 0 10 Armeen 2HT/Vikolox 18 2,6-Naphthalene 2/2.5/1 2.4 -2

Dicarboxylic Acid

11 Armeen 2HT/Vikolox 18 Tetrahydrofuran 2/2.5/1.1 6.9 7

Tetracarboxylic

Dianhydride

Riel B; 1000 ppm Additive

12 Armeen 2HT PMDA 2/1.1 2.2 0 13 Armeen 2HT BTDA 2/1.1 1.3 -2

Fuel B; 500 ppm Additive

14 Armeen 2HT/Vikolox 18 Trimellitic Anhy 3/3/1 3.6 4

15 Armeen 2HT/Vikolox 18 Trimellitic Anhy 2/2/1 3.3 2

16 Armeen 2HT/Vikolox 14-20 Trimellitic Anhy 3/3/1 3.6 4

TABLE 3

Core/Pendant Group Structures

Categories B, C, (See below)

Performance

Improvement (F):

Mole Cloud Point

Entry Pendant Group(s) Core Ratio (HERZOG) CFPP

Category B; "Bicyclic &

Alicyclic Cores"

Fuel A; 1000 ppm Additive

17 Armeen 2HT/Vikolox 18 Norbornene 2/2.5/1.1 6.5 6

Dicarboxylic

Anhydride

18 Armeen 2HT/Vikolox 18 Bicyclooctene 4/5/1.1 6.3 5

Tetracarboxylic

Dianhydride

19 Armeen 2HT/Vikolox 18 Camphoric Acid 2/2.5/1/1 3.4 2

20 Armeen 2HT/Vilolox 18 Cyclohexane 2/2.5/1.1 5.4 4

Dicarboxylic

Anhydride

Category C; "Alkyl Core"

Fuel A; 1000 ppm Additive

21 Armeen 2HT/Vikolox 18 Butyl Citrate 3/4/3.3 4.5 6

22 Armeen 2HT/Vikolox 18 Maleic Arihydride 2/2.5/1.2 9 7

23 Armeen 2HT/Vikolox 18 Hystrene 3695 1.05/1.3/1 1.3 2

24 Armeen 2HT/Vilolox 18 Hystrene 5460 2.6/3.25/1 2.4 4

TABLE 4

Post-Reacted Core/Pendant Group Structures

Category D: Multifunctioncil Cores

Performance

Improvement (F) :

Core/Post Mole Cloud Point

Entry Pendant Group(s) Reactant Ratio (HERZOG) CFPP

Fuel A; 1000 ppm Additive

25 Armeen 2HT/Vikolox 18 PMDA/UCON 2/2.5/ 5.2 2

LB-1145 1.1/1.05

26 Armeen 2HT/Vikolox 18 BTDA/UCON 2/2.5/ 4.9 2

LB-1145 1.1/1.05

27 Armeen 2HT/Vikolox 18 FMDA/Jeffamine 2/2.5/ 6.7 6

M-600 1.1/1.05

28 Armeen 2HT/Vikolox 18 BTOA/Jeffamine 2/2.5/ 6.8 11

M-600 1.1/1.05

29 Armeen 2HT/Vikolox 18 PMDA/Surfonamine 2/2.5/ 8.2 4

MNPA-380 1.1/1.05

30 Armeen 2HT/Vitoolox 18 BTDA/Surfonamine 2/2.5/ 8.0 6

MNPA-380 1.1/1.05

31 Jef famine M-600 PMDA 1/1 0.7 -2

32 Jef famine M-600 BTDA 1/1 0 4

33 Armeen 2HT/Vikolox 18 BTDA/E-100 2/2.5/ 6.5 11

1.1/.5

34 Armeen 2HT/Vikolox 18 EMDA/E-100 2/2.5/ 7.4 11

1.1/.5

35 Armeen 2HT/Vikolox 18 Maleic ANHY/TEPA 2/2.5/ 6.8 4

1.2/0.5

36 Armeen 2HT/Vikolox 18 Maleic ANHY/TEPA 2/2.5/ 7.4 6

1.2/0.3

Claims

1. A reaction product preparable by reacting :

i) a compound comprising a hydrocarbyl anhydride group, or a hydrocarbyl carboxylic acid group, the latter having at least two

carboxylic acid groups; with

ii) an aminoalcohol; and

iii) optionally, a secondary amine at a

temperature from 85º to 250ºC and a pressure from ambient to greater than autogenous to obtain the desired ester or ester/amide reaction product.

2. A product according to claim 1 wherein the

hydrocarbyl group in (i) comprises an aromatic, alicyclic, aralkyl, alkaryl or alkyl group

containing up to C₁₀₀; and heteroatom containing analogues.

3. A product according to claim 2 wherein the

hydrocarbyl group in (i) is an aromatic or

quinonoid group.

4. A product according to claim 3 wherein (i)

comprises pyromellitic anhydride; phthalic

anhydride, isophthalic acid; trimesic acid;

2,6-naphthalene dicarboxylic acid or 3, 3',4,4'- benzophenonetetracarboxylic dianhydride.

5. A product according to claim 2 wherein the

hydrocarbyl group in (i) is an alicylic or

bicyclic group.

6. A product according to claim 5 wherein (i)

comprises camphoric acid; cyclohexane dicarboxylic acid; norbornene dicarboxylic anhydride,

bicyclooctene tetracarboxylic dianhydride; or tetrahydrofuran tetracarboxylic dianhydride.

7. A product according to claim 2 wherein (i)

comprises butyl citrate; maleic anhydride; or a mixture of dimer and trimer acids.

8. A product according to any preceding claim wherein (ii) comprises the reaction product of an olefin epoxide and a secondary amine.

A product according to claim 8 wherein the olefin epoxide comprises a mixture of C₂₀ to C₂₈ alpha olefin epoxides.

10. A product according to any preceding claim wherein the secondary amine comprises ditallow amine, di(hydrogenated tallow) amine, dioctadecylamine, methyloctadecylamine, or a mixture thereof.

11. A product according to any preceeding claim which has the formula :

wherein:

Q represents the residue of i); R, and R₃, which may be the same or different, each represent a C₈ to C₅₀ saturated or unsaturated linear hydrocarbyl group; R₂ represents a C₁ to C₁₀₀ hydrocarbyl group; and x represents a number from 0.5 to 4.

12. A product according to any of claims 1 to 10 which has the formula :

wherein:

Q, R₁, R₂ and R₃ are as defined in claim 11; and y and z represent numbers the sum of which is from 0.5 to 4.

13. A product according to any of claims 1 to 10 which has the formula: wherein :

Q, R₁, R₂, R₃, y and z are as defined in claim 12; and R₄ represents a hydrogen atom or a C₁ to C₅₀ hydrocarbyl group.

14. A product according to any of claims 1 to 10 which has the formula :

wherein :

Q, R₁, R₂, R₃, R₄ are as defined in claim 13;

x is as defined in claim 11; and a represents a number from 1 to 3.

15. A product according to any of claims 1 to 10 which has the formula :

wherein :

Q, R₁, R₂, R₃, R₄ and a are as defined in claim 14; and y and z are as defined in claim 12.

16. A reaction product preparable by reacting the

product of any of claims 1 to 15 with a

mono-capped propylene glycol; an amino-polyether or a polyethyleneimine at a temperature from 85 to 250°C and a pressure from ambient to

autogenous.

17. A concentrate solution which comprises a reaction product according to any of claims 1 to 16

dissolved in at least one inert liquid hydrocarbon solvent.

18. A concentrate solution according to claim 17 which comprises from 1 to 50 grams of reaction product per 100 ml of solution.

19. An improved fuel composition which comprises a

minor amount of a reaction product according to any of claims 1 to 16 and a major amount of a liquid hydrocarbon fuel.

20. A fuel composition according to claim 19 which

comprises from 0.001% to 10% by weight of the total composition of reaction product.

21. A fuel composition according to claim 19 or 20 wherein the liquid hydrocarbon fuel comprises distillate fuel or fuel oil.

22. A fuel composition according to claim 21 wherein the fuel oil comprises fuel oil numbers 1, 2 and 3; diesel fuel; or jet combustion fuel.

23. Use of a reaction product according to any of

claims 1 to 16 to lower the cloud point and/or lower the cold filler plugging point of distillate fuel or fuel oil.