UA104854C2 - Thribble copolymer of ethylene/vinyl acetate/unsaturated esters as an additive enhancing low-temperature properties of liquid carbohydrates - Google Patents

Abstract

The invention pertains to the use, as an additive enhancing the low-temperature resistance and filterability of foels, of at least one copolymer comprising • from 78 to 87 mol% of at least one alpha-olefin, preferably at least ethylene, • from 12 to 18 mol% of at least one vinyl ester, preferably at least vinyl acetate, • from 1 to 4 mol% of at least one ester of alpha, beta unsaturated monocarboxylic acid, preferably at least 2-ethylhexyl acrylate.

Description

The field of technology to which the invention belongs

The invention relates to the use of copolymers of alpha-olefin, complex vinyl ether and alpha-, beta-unsaturated complex ester of carboxylic acid as additives that increase the cold resistance of motor fuels and lubricating oils, as well as heavy petroleum fuels, and sets of additives containing these copolymers.

Technical level

In conditions of low temperatures, the rheological properties of hydrocarbon compositions, in particular based on middle distillates containing paraffins, such as, for example, diesel fuels and municipal fuels, deteriorate significantly. It is well known that the crystallization of paraffins is a limiting factor in the use of middle distillates. In connection with this, an important task is the creation of diesel fuels suitable for the temperatures at which they are used in vehicles, that is, for ambient temperatures. Basically, the operating properties of motor fuels are preserved at a temperature of -10 "C, which is quite sufficient for many countries with a hot or temperate climate. However, in countries with a cold climate, such as the Scandinavian countries, Canada and the countries of North Asia, the temperature of using motor fuels can reach values much lower than -20 "С. This also applies to domestic petroleum fuels that are stored in the open air, and not inside buildings (houses, living quarters, etc.). The ability of middle distillates used as motor fuels to maintain their performance properties at low temperatures is very important, especially when starting a cold engine. If paraffins crystallize at the bottom of the tank, when starting the engine, they can enter the fuel supply system and, in particular, clog the filters and the pre-cleaning filters located in front of the fuel injection systems (pump and injector). Similarly, when storing domestic petroleum fuel, paraffins settle to the bottom of the tank and can get into the pipes and clog them in front of the pump and the boiler fuel supply system (nozzle and filter). It is obvious that the presence of solid particles, such as paraffin crystals, prevents the normal circulation of middle distillates.

To improve their circulation both in the engine and when supplying fuel to boilers, various types of additives appeared.

Initially, oil refining industry enterprises engaged in the development of additives that improve the low-temperature properties of liquid fuel (SR additives), which contribute to the dispersion of paraffin crystals, thereby preventing their aggregation into large structures that can lead to clogging of filter pores. Such additives usually affect the filterability limit temperature (FTT) and flow loss temperature, but do not change the cloud point.

Numerous additives that increase cold resistance are known from the prior art (see, for example, 05 3,038,479, 05 3,627,838, 05 3,790,359, Sh5 3,961,961, EP 261957), which are usually copolymers of ethylene and an unsaturated ester, such as copolymers of ethylene and vinyl acetate ( EVA), ethylene and vinyl propionate (EVP), ethylene and vinylethanoate (EVE), ethylene and methyl methacrylate (EMMA) and ethylene and alkyl fumarate.

From the state of the art, there are also mixtures of conventional SREI additives developed in order to improve the properties of conventional SR additives, such as a copolymer of ethylene and an unsaturated complex ether with lubricants (esters of mono- or polybasic carboxylic acids and esters of mono- or polyhydric alcohols (see, for example, patent EP 721492), with anti-sedimentation additives (see, for example, patent EC 2490669) or with esters (see, for example, patents 5 3,999,960, EP 187488).

Also known are improved SI additives, which are ternary copolymers or copolymers obtained from more than three separate monomers.

For example, patent 05 6,509,424 describes a method of obtaining ternary copolymers of ethylene and at least two compounds containing ethylenic unsaturated bonds, such as complex vinyl ethers, ethers of (meth)acrylic acid, alkyl vinyl ethers, in a tubular reactor. These ternary copolymers can be used as additives that improve the cold flow of petroleum products and petroleum distillates.

In patent O5 3,642,459, ternary copolymers containing from 40 to 89 wt. 9% of ethylene, from up to 40 wt. 95 complex vinyl ether obtained from a short-chain carboxylic acid (Сб2-С4), such as vinyl acetate, and unsaturated monoesters having an alkyl chain С10-С22); these ternary copolymers are used as additives to reduce the pour point of oil distillates and as anti-paraffin additives, as well as to improve their filterability.

Patent O5 4,156,434 describes ternary copolymers of ethylene, vinyl acetate, and carboxylic acid ester obtained from C12-C24 alcohol, which reduce the pour point when added to motor fuels, but nothing is said about improving the filterability at low temperatures of these additives.

UMO application 2005/054314 describes the used ternary copolymers of alpha-olefin, complex vinyl ether and alpha-, beta-unsaturated complex ester of monocarboxylic acid. Examples of ternary copolymers, which the applicant considers to be the best, containing more than 80 mol. 95 ethylene and less than 9 mol. 9 o vinyl acetate. Although these ternary copolymers containing less than 9 mol. 9Uo of vinyl acetate, contribute to lowering the limit temperature of cold filterability (GTP) of middle distillates containing more than 18 95 p-paraffins, they do not meet the requirements, on the one hand, regarding solubility, on the other hand, regarding the tendency to filter clogging (or filterability at ambient temperature): dangerous clogging of filters is observed.

EP 1391498 describes additives that improve the fluidity of middle distillates at low temperatures, namely: vinyl polymers (A), mainly copolymers of ethylene and complex vinyl ether, in which the amount of materials insoluble in hexane exceeds 60 wt. 95 at -

C and is less than 30 wt. 95 at 10 "С; the examples given in the patent EP 1391498 clearly show that in relation to copolymers and ternary copolymers, in which the amount of material insoluble in hexane exceeds 60 wt. 9o at -20 "С and is less than 30 wt. 9o at 10 C, the cold filterability limit temperature (CFT) is reduced compared to copolymers and ternary copolymers having the same repeating units, present in the same proportions, but in which the amount of materials insoluble in hexane is outside the stated range ; examples include copolymers of EVA and ternary copolymers of ethylene, vinyl acetate and neodecanoate or 2-ethylhexanoate.

Until now, the task has not been solved - in order to avoid clogging of filters in fuel supply systems in engines and boilers (injection systems and tanks), to create additives to improve the cold resistance of motor fuels (HTF and loss of fluidity temperature) while reducing or even eliminating the risk of clogging filters .

Description of the invention

This invention relates to the use of copolymers as additives that increase the cold resistance of motor fuels (CE additives); these copolymers contain units derived from at least one alpha-olefin, at least one vinyl ester, and at least one alpha-, beta-unsaturated monocarboxylic acid ester, and are preferably ternary copolymers of ethylene, vinyl acetate, and 2-ethylhexyl acrylate.

Copolymers according to the invention, which can be used as SEI additives, include: "- 78-87 mol. 95 of at least one alpha-olefin, preferably at least ethylene, "12-18 mol. 95 of at least one complex vinyl ether, preferably at least vinyl acetate, "- 1-4 mol. 95 of at least one alpha-, beta-unsaturated monocarboxylic acid ester, preferably at least 2-ethylhexyl acrylate.

The best effect is achieved when the copolymers according to the invention, which can be used as SEI additives, include: "- 78-87 mol. 95 ethylene, "12-18 mol. 95 vinyl acetate, preferably 12-16 mol. 9bo, "1-4 mol. 95 of 2-ethylhexyl acrylate, preferably 1.5-3.5 mol. 95.

Copolymers of the invention, which are statistical copolymers, typically have a number average molecular weight (Mm/) as determined by the standard GPC method, which is generally 3,000-30,000, and a weight average molecular weight (Mp) as determined by the standard GPC method. which is mostly 1,000-15,000.

These copolymers can be obtained in a known manner using any polymerization method (see, for example, Shitapp'5 Epsusioredia oi IpdiviyaI Spetivzigu, 5 Eliop, "U/akhev", Moi.

A 28, p. 146; 05 3,627,838; EP 7590), in particular by radical polymerization, preferably under high pressure, as a rule, of the order of 1,000-3,000 bar (100-300 MPa), preferably 1,500-2,000 bar (150-200 MPa), the reaction temperature is mainly in the range of 160 up to 320 "С, preferably from 200 to 280 "С, and in the presence of at least one radical initiator selected, as a rule, from organic peroxides and/or oxygen-containing or nitrogen-containing compounds, and a molecular weight regulator (ketone or aliphatic aldehyde, etc.) . Copolymers can, for example, be produced in a tubular reactor by the method described in patent 05 6,509,424.

Compositions based on hydrocarbons, which include copolymers according to the invention, are selected from all types of petroleum fuels or motor fuels, such as diesel fuel, household petroleum fuel for heating installations (PP), kerosene, aviation fuel, heavy diesel fuel, etc.

The sulfur content of the hydrocarbon compositions is generally less than 5,000 ppt, preferably less than 500 ppt, more preferably less than 50 ppt or even less than 10 ppt, most preferably the compositions are sulfur free.

Hydrocarbon-based compositions contain middle distillates with boiling points in the range of 100 to 500 °C; their onset of crystallization temperature (PTC) is often -20 °C or higher and generally ranges from -15 to 10 °C These distillates can, for example, be selected from distillates obtained by direct distillation of hydrocarbon feedstock, vacuum distillation distillates, hydrotreated distillates, distillates obtained by catalytic cracking and/or hydrocracking of vacuum distillates, distillates obtained as a result of type conversion

DSPV (desulfurization of distillation products) and/or visbreaking processes, distillates obtained as a result of refinement of fractions according to Fischer-Tropsch, distillates obtained according to the technology of VT. or as part of a mixture, and complex esters of vegetable oils and animal fats or their mixture.

Hydrocarbon compositions may also contain distillates obtained during oil processing, which are more complex compared to distillates obtained by direct distillation of hydrocarbons, for example by cracking, hydrocracking and/or catalytic cracking and visbreaking methods.

They may also contain new sources of distillates, among which should be mentioned, in particular, such as: - the heaviest fractions obtained by cracking and visbreaking methods, with a high concentration of heavy paraffins containing more than 18 carbon atoms, - synthetic distillates obtained at gas processing, such as distillates obtained by transformation according to the Fischer-Tropsch process, - synthetic distillates obtained by processing biological material of plant and/or animal origin, in particular obtained by MEHVTI technology, - oils and fats and/or complex esters of vegetable oils and /or animal fats, - or biodiesel fuel based on oils and fats of vegetable and/or animal origin.

These new motor fuel components can be used alone or in a mixture with conventional petroleum middle distillates as a motor fuel base and/or a household petroleum fuel base; as a rule, they include long paraffin chains that contain 10 or more carbon atoms and preferably C14-C30.

The above copolymers with Mu/ from 5,000 to 27,000 and Mp from 1,500 to 22,000, preferably with Mu/ from 5,000 to 25,000 and Mp from 1,500 to 20,000 are particularly effective when introduced into light middle distillates and/or low sulfur distillates (usually less than 50 ppm) and/or at a low initial crystallization temperature (typically -20 C). Light middle distillates are distillates in which the content of p-paraffins having 24 or more carbon atoms ranges from 0 to about less than 0.7 wt. 95 from the total mass of the fuel composition; at the same time, p-paraffins C18-C23 make up from about 3 to about 5 95 of the entire mass of motor fuel, and the mass ratio of p-paraffins C18-C23 and p-paraffins C24 mainly ranges from 10 to 35.

Copolymers with Mu from 5,000 to 10,000 and Mp from 1,500 to 8,000, preferably with Mu from 5,000 to 8,000 and

MPs from 1,500 to 5,000 are particularly effective when introduced into heavy middle distillates and/or at elevated initial crystallization temperatures (which typically range from 0 to 15 C). Heavy middle distillates mean distillates in which the content of p-paraffins having 24 or more carbon atoms ranges from about 0.7 to about 2 wt. 95 from the total mass of the fuel composition; at the same time, p-paraffins C18-C23 make up from about 1 to about 10 95 of the entire mass of motor fuel, and the mass ratio of p-paraffins C18-C23 and p-paraffins C24 mainly ranges from 1 to 10.

Copolymers can be added to hydrocarbon compositions by themselves or preferably in the form of concentrated solutions, in particular solutions containing from 50 to 80 wt. 95, preferably from 60 to 70 mabs.95 of the copolymer(s) in a solvent such as aliphatic or aromatic hydrocarbons, alone or in a mixture (gasoline, kerosene, hydrocarbon fractions such as aromatic petroleum fractions, paraffinic hydrocarbons such as pentane, hexane ).

According to a preferred embodiment of the invention, the hydrocarbon compositions contain from 10 to 5,000 ppt by weight of at least one copolymer described above, preferably from 100 to 1000 ppt, most preferably from 150 to 500 ppt.

In addition to the SERIES additives described above or additives that increase cold resistance, hydrocarbon compositions may also contain one or more other additives, other than the copolymers of the invention, selected from detergent additives, anti-corrosion agents, dispersants, demulsifiers, antifoam agents, biocides, fragrances, procetane additives , friction improvers, lubricity additives or antifriction additives, combustion aids (catalytic combustion activators that prevent the formation of soot), improvers of cloud point, pour point, filterability limit temperature, anti-sediment additives, anti-wear additives and/or improvers permeability

Among these additives, we should first mention: a) procetane additives, in particular (but not limited to) selected from alkyl nitrates, preferably 2-ethylhexyl nitrate, aroyl peroxides, preferably benzyl peroxide, and alkyl peroxides, preferably tert-butyl peroxide;

B) antifoam agents, in particular (but not limited to) selected from polysiloxanes, oxyalkylated polysiloxanes and amides of fatty acids obtained from vegetable oils or animal fats. Examples of such additives are given in EP 861882, EP 663000, EP 736590;

c) detergents and anticorrosive additives, in particular (but not limited to) selected from the group containing amines, succinimides, alkenylsuccinimides, polyalkylamines, polyalkyl polyamines and polyetheramines. Examples of such additives are given in EP 938535; a) an additive that improves lubricity, or an anti-wear additive, in particular (but not limited to this), selected from the group containing fatty acids and their ester or amide derivatives, in particular glycerol monooleate, and derivatives of mono- and polycyclic carboxylic acids. Examples of such additives are given in the following documents: patents EP 680506, EP 860494, MO 98/04656, EP 915944, EC 2772783,

EV 2772784; f) cloud point lowering additives, in particular (but not limited to) selected from the group consisting of ternary copolymers of long-chain olefin, (meth)acrylic ester and maleimide, and polymers of fumaric and maleic acid esters. Examples of such additives are given in patents EP 71513, EP 100248, EC 2528051, EC 2528051, RE 2528423, EP 112195,

ER 172758, ER 271385, ER 291367;

I) anti-sediment additives and/or paraffin dispersants, in particular (but not limited to) selected from the group containing copolymers of (meth)acrylic acid and polyamine-amidated alkyl (meth)acrylate, alkenyl succinimides, derivatives of terephthalic acid and two-chain fatty amine; alkylphenolic resins. Examples of such additives are given in patents EP 261959, EP 593331, EP 674689, EP 327423, EP 512889, EP 832172, 05 2005/0223631; 005 5,998,530; MO 93/14178; 9) universal additives that ensure operation in cold weather, selected from the group consisting of polymers based on olefin and alkenyl nitrate, described in patent EP 573490;

P) other SRI additives that improve cold resistance and filterability, such as EVA and/or EVP copolymers.

These other additives are usually added in amounts of 100 to 1,000 ppt (each).

Improved additives according to the invention, which increase cold resistance, can be added to hydrocarbon compositions at the refinery and/or can be introduced after leaving the refinery, optionally mixed with other additives, in the form of a set of additives.

Examples

Ternary copolymers of ethylene, vinyl acetate and 2-ethylhexyl acrylate were synthesized in a tubular reactor by radical polymerization under high pressure conditions (from 1,400 to 2,500 bar (140-250 MPa)) and at a polymerization temperature of 200 to 280 "C. The synthesis was carried out using an aliphatic aldehyde (propionic aldehyde) to control molecular weights and with the help of peroxides as polymerization initiators.Table 1 shows the values of Mp and Mu/ of the synthesized ternary copolymers, as well as the percentage content of monomers in them.

Table 1

Characteristics of synthesized copolymers 11111111 masoov | mol.be | masbe | minor 7717178... 1,245 | 71 | 98 | 271 | 2480 | 6990 71717174 71 27 | 121 | 9 | 79 | 2687 | 14775 about b(comparison) | 133 | 66 | 221 | 51 | 12627 | 14610 o in (compare) | 179 | 89 | 168 | 39 | 12875 | 15675

Lv (comparison) | 1993 | 96 | 215 | 5 | 4498 | 8443

The ability to increase the cold resistance of these ternary copolymers was evaluated when they were included in six distillates of the gas oil type for engines, known as ГОМ 1 - ГОМ 6 (winter diesel fuel), the characteristics of which are shown in Table 2.

Table 2

Characteristics of motor fuels 11111111 gm | home2 | hum | homa | GOM | home

Distillation zgidozAZTMO86 C | 77771Ї11Ї11Ї111111111Ї1 t9o-t20sse) 77777771 11127 | 1004 | 969 | 1122 | 1005 | 112

Cloud point (C) according to ssandaromnesmoih 01859 ee ( filterability (GTF) (C) -5 -7 -5 according to standard EM 116

Freezing point (С) according to your standard 0007202

Paraffins (wt. 95) are guilty! with | c) v) vz| tv of crystallization (TPK) of paraffins (C) according to -6.3 -6.2 -6.3 -12.6 -9.5 standard IR 389 (Content of sulfur (ppt) EMI5O 20846. | 398 | z8 | 9 | 95 | 92 | 48

400 ppt by weight of each copolymer 1-16 was injected into a diesel-type distillate for engines called HOM 1, then the EVT (filter clogging tendency) was measured according to the IR 387 standard. HOM 1 without additives has an EVT of 1.01 .

It was found that the ternary copolymers according to the invention do not lead to a deterioration of the indicator of the tendency to clogging of fuel HOM 1 filters, that is, HOM 1 with the addition of 400 ppt of the ternary polymer has an EVT indicator of less than 1.41. The results are shown in Table 3.

Table C

The tendency to clogging of filters (IR 387) of fuel GOM 1 with the addition of 400 ppt of various ternary polymers is added

The behavior of fuels at low temperatures when adding ternary copolymers to HOM 2 - HOM 6 was tested at a concentration of 140, 210 or 280 ppm; the results are shown in the table

Table 4

Low-temperature performance testing of various low-sulphur light diesel fuels

Added additive 17113 14 174 | 777112 7774171 21 | 76 18 Her | 17771112 51975 17777711 11 75 | 72 | Liu 61111112 1 716-565 17777777711117111 75 | 72 | 9 81111112 1 81111112 1 70712 73 17777771 1 of | 3 | syu 11711 1771111111111711 with | 3 | at 712 11114115 | Shshsh Her a | 1 of 718 51141111 11111111 774712 | 1 11111115 177 | syu 77167117 | 76 17777771 1 74 | l2 | with

It should be noted that ternary copolymers 1; 2; 3; 4 according to the invention are the most effective in various diesel fuel GOM 2 - GOM 6. In addition, the data in Table C indicate that these ternary copolymers 1; 2; 3; 4, added in the amount of 400 ppt to GOM 1, do not worsen the tendency to filter clogging, in contrast to the compared ternary copolymers 6; 7; 8; 9; 11 and 16, described in UMO application 2005/054314, which significantly worsen the filter clogging tendency measured according to the IR 387 standard, and which are also less effective in reducing GTP than additives according to the invention, such as, for example, additives 1 ;2;4 and 5.

Claims (10)

1. Application of at least one copolymer containing: 78-87 mol. 9o at least one alpha-olefin, preferably at least ethylene, 12-16 mol. 9o at least one complex vinyl ether, preferably at least vinyl acetate, 1-4 mol. 96 of at least one ester of an alpha-, beta-unsaturated monocarboxylic acid, preferably at least 2-ethylhexyl acrylate. 2. Application according to item I of at least one ternary copolymer containing: 78-87 mol. of ethylene, 12-16 mol. 90 vinyl acetate, 1-4 mol. 96 of 2-ethylhexyl acrylate. 3. Use according to item 1 or 2 of at least one copolymer with a number average molecular weight (Mw), determined by the HPU method, from 3,000 to 30,000, preferably from 3,000 to 20,000, 1 weight average molecular weight (Mp), determined by the HPU method, which ranges mainly from 1,000 to 20,000, preferably from 1,500 to 15,000. 4. Application according to any of claims 1-3, where the motor fuels and middle distillates are selected from diesel fuel, domestic oil fuel for heating installations (PP), kerosene, aviation fuel, heavy diesel fuel. 5. Application according to any of claims 1-4 of at least one copolymer as an additive that increases the cold resistance and filterability of motor fuels, the sulfur content of which is less than 5,000 ppt, preferably less than 500 ppt, even better less than 50 ppt or even less than 10 ppt, best when the additive is sulfur free. b. Hydrocarbon composition containing a larger amount of middle distillate with a boiling point in the range of 100 to 500 "C, 1 smaller amount of at least one copolymer according to any of claims 1-5. 7. The composition according to claim 6, which differs in that the middle distillate contains from 0 to 100 wt. o biodiesel fuel based on oils and fats of vegetable and/or animal origin. 8. The composition according to item b or 7, which differs in that it is selected from diesel fuel, household oil fuel for heating installations (PP), kerosene, aviation fuel, heavy diesel fuel. 9. The composition according to any one of claims 6-8, which is characterized in that it contains from 10 to 5,000 ppt by weight of at least one copolymer according to any one of claims 1-5, preferably from 100 to 1000 ppt, most preferably from 150 to 500 ppt 10. The composition according to any of claims 6-9, which is characterized by the fact that it contains one or more other additives, other than the copolymers according to the invention, selected from detergent additives, anti-corrosion agents, dispersants, demulsifiers, antifoam agents, biocides, fragrances, procetane additives, friction improvers, lubricity additives or anti-friction additives, substances that promote combustion (catalytic combustion activators that prevent the formation of soot), improvers of cloud point, pour point, filterability limit temperature, anti-sediment additives, anti-wear additives and / or permeability improvers.