EP1124916B1 - Paraffin dispersants with a lubricity effect for distillates of petroleum products - Google Patents

Abstract

The mixture contains(a) from 5 to 95% by weight of at least one reaction product of a poly(C2-20-carboxylic acid) having at least one tertiary amino group with secondary amines and(b) from 5 to 95% by weight of at least one reaction product of maleic anhydride and a primary alkylamine.

Description

This invention relates to paraffin dispersants having lubricity effects suitable mixtures, their use in petroleum middle distillates, such petroleum middle distillates and concentrates therefor.

Petroleum distillates, in particular middle distillates such as gas oils, diesel oils or light heating oils, which are obtained by distillation from petroleum oils, have different contents of paraffins depending on the origin of the crude oil. At lower temperatures, solid paraffins are excreted (cloud point or cloud point, CP). Upon further cooling, the platy n-paraffin crystals form a kind of "house of cards structure" and the middle distillate stagnates, although the majority of the middle distillate is still liquid. The precipitated n-paraffins in the temperature range between cloud point (cloud point) and pour point (pour point), the flowability of middle distillate fuels is significantly affected; The paraffins clog filters and cause uneven or completely interrupted fuel supply to the combustion units. Similar disturbances occur with light fuel oils.

It has long been known that by suitable additives, the crystal growth of the n-paraffins in the petroleum middle distillate fuels and fuels can be modified. Good effective additives prevent middle distillates from becoming solid at temperatures a few degrees Celsius below the temperature at which the first paraffin crystals crystallize out. Instead, be formed fine, well crystallizing, separate paraffin crystals, which pass filters in motor vehicles and heating systems or at least form a permeable for the liquid part of the middle distillates filter cake, so that a trouble-free operation is ensured. The effectiveness of the flow improvers is expressed indirectly according to the European standard EN 116 by measuring the Cold Filter Plugging Point (CFPP).

Ethylene vinyl carboxylate copolymers have long been used as flow improvers. A disadvantage of these additives is that the precipitated paraffin crystals tend due to their relative to the liquid part higher density tend to settle more and more at the bottom of the container during storage. As a result, a homogeneous low-paraffin phase forms in the upper container part and a two-phase paraffin-rich layer at the bottom. Since the deduction of the middle distillate mostly takes place slightly above the container bottom both in the vehicle tanks and in storage or delivery tanks of the mineral oil dealer, there is a risk that the high concentration of solid paraffins leads to blockages of filters and metering devices. This danger is greater the further the storage temperature falls below the excretion temperature of the paraffins, since the amount of paraffin precipitated increases with decreasing temperature.

The additional use of wax dispersants (wax anti-settling additives) can reduce these problems.

Thus, EP-A-0 398 101 describes reaction products of aminoalkylene polycarboxylic acids with long-chain secondary amines as paraffin dispersants for petroleum middle distillates. However, the effect is not sufficient in all petroleum middle distillate compositions, especially if they have a low sulfur content of less than 500 ppm.

DE-A-11 49 843 describes the use of maleamic acids and their amine salts of primary amines and maleic anhydride as corrosion inhibitors and stability improvers for petroleum distillates as well as for the prevention of sedimentation. EP-A-0 106 234 describes the use of amine salts of maleamic acids from primary amines and maleic anhydride as corrosion inhibitors for the storage and transport of crude oils.

Since October 1996, only low-sulfur middle distillates with a maximum sulfur content of 500 ppm may be used in the European Union as diesel fuels, which therefore contribute to low-emission exhaust gases. From the year 2000, the maximum permissible sulfur content of diesel fuel in the European Union may not exceed 350 ppm. However, such diesel fuels show a markedly reduced lubricity, which can lead to partially high mechanical wear in distributor injection pumps of diesel engines.

The addition of lubricity additives can improve the lubricity of low-sulfur diesel fuels. The effectiveness is determined according to the standard CEC F-06-A-96 with the HFRR test (High Frequency Reciprocating Rig-Test) by determining the wear size WS1.4 in μm at 60 ° C; the smaller the WS1.4, the lower the wear and the better the lubricity.

There are numerous patent applications for products which can improve the lubricity of low sulfur diesel fuels. In WO 95/33805 it is described that flow improvers and paraffin dispersants, inter alia also reaction products according to EP-A-0 398 101, can improve the lubricity (lubrication) of middle distillates. However, the lubricity effect is not sufficient in many petroleum middle distillate compositions.

WO-A-9 746 640 describes a mixture comprising (a) 10 to 90% by weight of at least one imide of a copolymer based on an α-olefin and an ethylenically unsaturated dicarboxylic acid and a polyamine and (b) 10 to 90 % By weight of at least one reaction product of a poly (C _2-20 -carboxylic acid) having at least one tertiary amino group with secondary amines, and their use as paraffin dispersants in petroleum middle distillates.

The object was to provide improved products which ensure improved flowability of petroleum middle distillates at low temperature by having such a dispersing effect that delaying or preventing settling of precipitated paraffins and simultaneously contributing to improved lubricity of the petroleum middle distillates ,

• (a) 5 bis 95 Gew.-% mindestens eines Umsetzungsproduktes einer mindestens eine tertiäre Aminogruppe aufweisenden Poly(C_2-20-Carbonsäure) mit sekundären Aminen und
• (b) 5-95 Gew.-% mindestens eines Umsetzungsproduktes aus Maleinsäureanhydrid und einem primären C_8-30-Alkylamin.

The object is achieved by a mixture containing

• (A) 5 to 95 wt .-% of at least one reaction product of at least one tertiary amino group-containing poly (C _2-20 carboxylic acid) with secondary amines and
• (B) 5-95 wt .-% of at least one reaction product of maleic anhydride and a primary C _8-30 alkylamine.

The invention also relates to the use of these mixtures as an additive for petroleum middle distillates, in particular as paraffin dispersant and lubricity additive. The invention also relates to these mixtures containing concentrates and petroleum middle distillates.

Component (a)

Component (a) is a reaction product of a tertiary amino group containing poly (C _2-20 carboxylic acid) with secondary amines.

The polycarboxylic acid preferably contains at least 3 carboxyl groups, particularly preferably 3 to 12, in particular 3 to 5, carboxyl groups. The carboxylic acid groups in the polycarboxylic acid preferably have 2 to 10 carbon atoms, preferably acetic acid groups. The carboxylic acid groups are suitably linked to the polycarboxylic acid, for example via one or more C and / or N atoms. Preferably, they are attached to tertiary nitrogen atoms, which are linked in the case of several nitrogen atoms via hydrocarbon chains.

wobei A einen geradkettigen oder verzweigten Alkylenrest mit 2 bis 6, vorzugsweise 2 bis 4, insbesondere 2 oder 3 Kohlenstoffatomen oder den Rest der Formel (III)

darstellt, wobei B ein 1 bis 19 Kohlenstoffatome aufweisender Rest, vorzugsweise ein C_1-19-Alkylenrest ist, besonders bevorzugt C_1-10-Alkylenrest, insbesondere ein Methylenrest ist. Vorzugsweise ist A ein Ethylenrest.Component (a) is preferably an amide, amide ammonium salt, ammonium salt or a mixture thereof of aminoalkylcarboxylic acids of the formulas I and II

where A is a straight-chain or branched alkylene radical having 2 to 6, preferably 2 to 4, in particular 2 or 3, carbon atoms or the radical of the formula (III)

where B is a radical having 1 to 19 carbon atoms, preferably a C _1-19 -alkylene radical, particularly preferably C _1-10 -alkylene radical, in particular a methylene radical. Preferably, A is an ethylene radical.

The secondary amine may be selected from a variety of amines carrying hydrocarbon radicals, optionally linked together.

The secondary amine preferably has the formula HNR ₂ , wherein the radicals R are independently straight-chain aliphatic radicals, in particular alkyl radicals having 10 to 30, preferably 14 to 24 carbon atoms. They preferably have no heteroatoms or double or triple bonds. Preferably, the radicals R are the same.

The secondary amines can be bound to the polycarboxylic acid by means of amide structures or in the form of the ammonium salts, partly also by means of amide structures and partly in the form of the ammonium salts. Preferably, there are little or no free acid groups.

Preferably, the amines are fully bonded in the form of the amide structures.

The amides, or amide ammonium salts or ammonium salts of nitrilotriacetic acid, ethylenediaminetetraacetic acid or propylene-1,2-diaminetetraacetic acid, for example, are prepared by reacting the acids with from 0.5 to 1.5 mol of amine, preferably from 0.8 to 1.2 mol Amine per carboxyl group.

The reaction temperatures are about 80 to 200 ° C, wherein for the preparation of the amides, a continuous removal of the resulting reaction water. However, the reaction does not have to be completely led to the amide, but may be 0 to 100 mol% of the amine used in the form of the ammonium salt. Especially preferred amines are dioleylamine, dipalmitinamine, dicoco fatty amine and dibehenylamine, especially ditallow fatty amine.

The mixture components (a) according to the invention and their preparation are described in EP-A-0 398 101. Particularly preferred is the reaction product of one mole of ethylenediaminetetraacetic acid and four moles of hydrogenated Ditalgfettamin.

Optionally, the mixture components (a) can still small amounts of conductivity in the form of salts, in particular of hydrocarbon-soluble carboxylic acids and sulfonic acids or their metal and ammonium salts. be added.

Component (b)

The preparation of the mixture components (b) according to the invention is carried out in a manner known per se by reacting maleic anhydride with primary C _8-30 -alkylamine. Preference is given to using primary C ₈ - to C ₁₈ -alkylamines in a molar ratio of 1: 1 at from 70 to 100 ° C. according to the process described in DE-A-11 49 843 and EP-A-0 106 234. Suitable primary amines are all amines defined within these limits, for example straight-chain or branched octyl, nonyl, decyl, undecyl, dodecyl, tricecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecylamine and mixtures these amines. Particularly preferred is the reaction product of one mole of maleic anhydride and one mole of tridecylamine.

The mixtures according to the invention can be prepared by simply mixing components (a) and (b); These mixtures are added to the petroleum distillates in amounts of 10-1000 ppm, preferably 50-500 ppm. The proportion of component (a) is 5 to 95, preferably 30 to 95, in particular 50 to 90 wt .-%, the proportion of component (b) 5 to 95, preferably 5 to 70, in particular 10 to 50 wt .-%.

The polymer blends of the invention are used as an additive for petroleum middle distillates, which are understood to include petroleum, light fuel oils and diesel fuels having a boiling point of about 150 to 400 ° C. The polymer mixtures can be added directly to the middle distillates, but preferably as a 20 to 70% by weight solution (concentrate). Suitable solvents are aliphatic or aromatic solvents such as xylene or mixtures thereof, furthermore high-boiling aromatic mixtures such as solvent naphtha, as well as middle distillates. The amount of the mixture in the petroleum middle distillates is usually 10 to 10,000, preferably 20 to 5000, and more preferably 50 to 1000 ppm.

In general, the middle distillates still contain flow improvers, e.g. based on ethylene / vinylcarboxilate copolymers. Depending on the intended use, middle distillates may additionally contain further additives such as conductivity improvers, anti-corrosive additives, lubricity additives, antioxidants, metal deactivators, anti-foam agents, demulsifiers, detergents, cetane number improvers and / or dyes and fragrances.

The mixtures according to the invention in middle distillates, irrespective of their origin, significantly improve the flow properties in the cold by effectively keeping the precipitated paraffin crystals in suspension, so that blockages of filters and lines by sedimented paraffin do not occur. They have a good broad effect and cause so that the precipitated paraffin crystals are dispersed very well in different middle distillates; at the same time they contribute to an improved lubricity of the middle distillates.

The effect of the combination of components (a) and (b) is significantly better than the effect of the individual components at the same dosage.

The invention will be explained in more detail below with reference to examples.

EXAMPLES: Example 1 (component (a))

240 g (0.48 mol) of hydrogenated di-tallow fatty amine (Armeen® 2HT from Akzo) and 35 g (0.12 mol) of ethylenediaminetetraacetic acid were melted and heated to 190 ° C., the reaction water being distilled off continuously. The reaction was stopped after about 25 hours at an acid number less than 10 and an amine number less than 1.1. By applying water jet vacuum (2 hours, 120 ° C), the water of reaction was completely removed. This gave 265 g of a light brown, waxy solid. The resulting product was diluted with solvent naphtha so that the solids content of the product was 50% by weight.

Example 2 (Component (b))

A mixture of 98 g (1.0 mol) of maleic anhydride and 199 g (1.0 mol) of tridecylamine was heated in 250 ml solvent naphtha at about 70 ° C for 2 hours with stirring. This gave a light brown, clear solution, which was then with Solvent naphtha was diluted so that the solids content of the product was 50 wt .-%.

Examples of use:

The mixtures according to the invention were tested in two commercial German winter diesel fuels, which correspond to the European diesel fuel standard EN 590; they are referred to as D 1 and D 2 and are characterized by the following physical data: D 1 (97/526) D 2 (96/86) Cloud Point (° C) according to ISO 3015: -6 -6 CFPP (° C) according to EN 116: -10 -8th Density at 15 ° C (kg / m ³ ) according to ASTM D 4052: 841 834 Sulfur content (ppm) according to EN 24260: 160 200 WS1.4 (μm) according to CEC F-06-A-96: 542 Distillation according to ISO 3405: Boiling start (° C) 170 171 5% boiling point (° C) 203 193 10% boiling point (° C) 215 200 20% boiling point (° C) 235 212 50% boiling point (° C) 280 249 70% boiling point (° C) 308 282 90% boiling point (° C) 347 329 95% boiling point (° C) 364 345 Boiling end (° C) 371 360

• 1. als Paraffindispergator
  eine der erfindungsgemäßen Mischungen PD 1 (bestehend aus 83 Gew.-% Komponente (a) aus Beispiel 1 und 17 Gew.-% Komponente (b) aus Beispiel 2), PD 2 (bestehend aus 50 Gew.-% Komponente (a) aus Beispiel 1 und 50 Gew.-% Komponente (b) aus Beispiel 2), PD 3 (bestehend aus 67 Gew.-% Komponente (a) aus Beispiel 1 und 33 Gew.-% Komponente (b) aus Beispiel 2) oder PD 4 (bestehend aus 90 Gew.-% Komponente (a) aus Beispiel 1 und 10 Gew.-% Komponente (b) aus Beispiel 2) bzw. als Vergleichsbeispiele die jeweiligen Einzelkomponenten aus Beispiel 1 und Beispiel 2 bzw. keine der Komponenten (Vergleichsbeispiele V2, V3, V1). V1 enthält damit nur MDFI als Additiv
  und
• 2. als Fließverbesserer MDFI
  ein Produkt auf Basis von Ethylen-Vinylcarboxilat, welches unter dem Handelsnamen Keroflux® ES 6100 von der BASF AG vermarktet wird.

The following petroleum middle distillate compositions were tested:
Petroleum middle distillate compositions containing

• 1. as a paraffin dispersant
  one of the inventive mixtures PD 1 (consisting of 83% by weight of component (a) from Example 1 and 17% by weight of component (b) from Example 2), PD 2 (consisting of 50% by weight of component (a) from Example 1 and 50% by weight of component (b) from Example 2), PD 3 (consisting of 67% by weight of component (a) from Example 1 and 33% by weight Component (b) from Example 2) or PD 4 (consisting of 90% by weight of component (a) from Example 1 and 10% by weight of component (b) from Example 2) or as comparative examples the respective individual components from Example 1 and Example 2 or none of the components (Comparative Examples V2, V3, V1). V1 contains only MDFI as an additive
  and
• 2. as flow improver MDFI
  a product based on ethylene-vinylcarboxilate, which is marketed under the trade name Keroflux® ES 6100 by BASF AG.

Description of the test method:

The middle distillates were added with the amounts indicated in the table mixtures of the invention PD 1 to PD 4 or Examples 1 and 2 and the flow improver MDFI at 40 ° C with stirring and then cooled to room temperature.

Of the additized middle distillate samples, the Cold Filter Plugging Point (CFPP) according to EN 116 and in some cases also the WS 1.4 according to CEC-F-06-A-96 was determined.

The additized middle distillates were placed in 500 ml glass cylinders in a room temperature refrigerated bath at a cooling rate of about 14 ° C per hour cooled to -13 ° C and stored at this temperature for 20 hours. Subsequently, the amount and appearance of the paraffin phase were determined and assessed visually.

From the 20% by volume soil phase separated at -13 ° C., the "cold filter plugging point" (CFPP) according to EN 116 and the cloud point (CP) according to ISO 3015 were determined from each sample. The smaller the deviation of the cloud point of the 20% by volume soil phase from the original CP of the respective middle distillate, the better the paraffins are dispersed.

The results obtained are shown in Tables 1 and 2: Table 1: Dispersing experiments in D 1, CP: -6 ° C, CFPP: -10 ° C, WS1.4: 542 μm mixture Dosage (ppm) MDFI (ppm) WS1.4 (μm) CFPP (° C) Paraffin sediment (% by volume) dispersed paraffins (% by volume) 20% -Bodenphase CFPP (° C) CP (° C) PD 1 150 200 -30 10 90 -29 -6 PD 2 150 200 310 -25 10 90 -27 -6 PD 3 150 200 -26 10 90 -28 -6 PD 4 150 200 328 -28 10 90 -27 -5 V1 - 200 526 -25 44 0 -18 0 V2 150 200 394 -25 46 54 -20 -2 V3 150 200 369 -23 42 58 -23 -3 mixture Dosage (ppm) MDFI (ppm) CFPP (° C) Paraffin sediment (% by volume) dispersed paraffins (% by volume) 20% -Bodenphase CFPP (° C) CP (° C) PD 1 300 300 -23 6 94 -18 -5 PD 3 300 300 -20 8th 92 -27 -5 PD 4 300 300 -29 8th 92 -20 -5 V1 --- 300 -22 30 0 -1 +3 V2 300 300 -30 10 90 -20 -3 V3 300 300 -20 30 70 -7 +2

The results of the experiments show that the mixtures according to the invention in petroleum middle distillates bring about a lower cloud point of the 20% bottom phase than the mixtures of the comparative examples.

This shows that regardless of their origin, the precipitated paraffin crystals are effectively kept in suspension by the inventive mixtures of components (a) and (b) in petroleum middle distillates, so that it can not come to blockages of filters and pipes by sedimented paraffin. The mixtures according to the invention have a very good broad action and cause the precipitated paraffin crystals to be dispersed very well in different middle distillates.

At the same time, the test results show that the mixtures according to the invention, with the same total metering, lead to a lower WS1.4 and thus to an improved lubricity of low-sulfur diesel fuels than the respective individual components.

Claims (10)

1. A mixture comprising

   (a) from 5 to 95% by weight of at least one reaction product of a poly(C_2-20-carboxylic acid) having at least one tertiary amino group with secondary amines and

   (b) 5-95% by weight of at least one reaction product of maleic anhydride and a primary C_8-30-alkylamine.
2. The mixture according to claim 1, wherein the poly(C_2-20-carboxylic acid) having at least one tertiary amino group is of the following formula I or II

   

   

   where A is a straight-chain or branched C_2-6-alkylene radical or a radical of the formula III

   

   where B is a C_1-19-alkylene radical.
3. The mixture according to claim 1 or 2, wherein the reaction product (a) is an amide, amidoammonium salt or ammonium salt in which no carboxyl group, one carboxyl group or a plurality of carboxyl groups is or are converted into amido groups.
4. The mixture according to any of claims 1 to 3, wherein the secondary amine of the component (a) is of the formula HNR₂, where R is straight-chain or branched C_10-30-alkyl.
5. The use of a mixture according to any of claims 1 to 4 as an additive for mineral oil middle distillates.
6. The use according to claim 5 as a paraffin dispersant and lubricity additive for mineral oil middle distillates.
7. A mineral oil middle distillate comprising a mixture according to any of claims 1 to 4.
8. The mineral oil middle distillate according to claim 7, furthermore comprising flow improvers, conductivity improvers, corrosion-inhibiting additives, lubricity additives, antioxidants, metal deactivators, antifoams, demulsifiers, detergents, cetane number improvers, dyes or fragrances or mixtures thereof.
9. A concentrate comprising 10-60% by weight, based on the total amount of the concentrate, of a mixture according to any of claims 1 to 4, dissolved in the hydrocarbon solvent.
10. The mineral oil middle distillate according to claim 7, which additionally comprises flow improvers based on ethylene/vinylcarboxylate copolymers.