Patent Application
20140157655
This application is a National Phase Entry of International Application No. PCT/EP2012/063532, filed on Jul. 11, 2012, which claims priority to French Patent Application Serial No. 1156363, filed on Jul. 12, 2011, both of which are incorporated by reference herein.
The present invention relates to additive compositions making it possible to improve the stability and engine performances of the gas oils used as diesel fuel, in particular gas oils of the non-road type.
Since the entry into force of the decree of 10 Dec. 2010, in France the term “gazole non routier” [non-road gas oil] denotes a mixture of hydrocarbons of mineral origin or from synthesis with 7 parts by volume of fatty acid methyl esters according to the minimum requirements of the standard EN 590 or any other standard or specification in force in the EU having a maximum sulphur content of 20 mg/kg at the distribution stage. Previously, domestic fuel oil (dfo) was intended both for heating applications and engine applications; since this Decree, the products are differentiated, i.e. distributed in different distribution networks and required to be stored in separate storage facilities in different networks according to their intended use: stationary applications (heating) on the one hand, and non-stationary applications (non-road gas oil). For heating applications, the fuel oil has a sulphur content of 1,000 pm mass whereas the non-road gas oil has a sulphur content less than or equal to 10 ppm by mass (tolerance 20 ppm); the cetane number of domestic fuel oil is 40 whereas that of non-road gas oil is 51 (better flammability).
In France the use of non-road gas oil, marketed via a specific distribution network and subject to a diferent tax regime to that of motor vehicles is mandatory for
For environmental reasons and/or because of the availability of resources, regulations in many countries encourage the introduction of constantly increasing quantities of products of renewable origin, such as fatty acid esters, into conventional gas oil and non-road gas oil. Thus, at present in the EU, the on-road gas oil used as diesel fuel can contain 7 parts by volume of fatty acid esters, generally fatty acid methyl esters (FAME), essentially or exclusively of vegetable or animal origin (vegetable and/or animal oil esters, in particular vegetable oil methyl esters or VOMEs).
In the past, the machinery engines operating with non-road gas oil were deemed to be unsophisticated and undemanding but the specifications of these engines have developed and are increasingly operating according to technologies as advanced (very high pressure direct injection technologies) as those of on-road motor vehicles. Standard-grade non-road gas oil (currently in compliance with the standard EN 590) sometimes poses problems in terms of:
The present invention proposes a high-grade on-road or non-road gas oil which has improved properties compared with the corresponding standard-grade on-road or non-road gas oil (EN 590). Within the meaning of the present invention, several of the properties of the standard gas oil are improved, and in particular the oxidation resistance, storage stability, thermal stability and engine performances (reduction in fouling of the injectors; the following improvements are also possible: reduction in the loss of power; reduction in the tendency of the filters to clog etc.); low-temperature performance (CFPP and pour point). The invention also relates to additive compositions capable of improving the properties of the gas oil, in particular of the non-road gas oil, such as oxidation resistance, storage stability, thermal stability, engine performances (reduction in fouling of the injectors); low-temperature performance (CFPP and pour point), reduction in loss of power, reduction the tendency of the filters to clog etc.) can also be improved. This additive composition added to the fuel (on-road or non-road gas oil) more particularly makes it possible to reduce the tendency of the injectors to be fouled by the fuel. The fouling of the injectors can lead to losses of power but also a degradation of combustion which is responsible for an increase in pollutant emissions.
Other advantages and characteristics will become more clearly apparent from the following description of particular embodiments of the invention given as non-limitative examples and represented in the single attached drawing in which
A first subject of the invention relates to additive compositions comprising the following components:
According to a particularly preferred embodiment, the additive compositions comprise the following components:
According to a particular embodiment, the metal passivator i) is chosen from the triazole derivatives, alone or in a mixture, for example benzotriazole derivatives. By “triazole derivatives” is meant all of the compounds comprising a triazole unit, i.e. a 5-membered aromatic cyclic unit, comprising two double bonds and 3 nitrogen atoms. According to the position of the nitrogen atoms, a distinction is drawn between the 1,2,3-triazole units (called V-triazoles) and the 1,2,4-triazole units (called S-triazoles). As examples of triazole units, benzotriazole or tolyltriazole can be mentioned.
The metal passivator i) can be chosen from the amines substituted by triazole groups, alone or in a mixture. By “triazole group” is meant any substituent containing a triazole unit as defined above. The metal passivator(s) i) can, for example, be chosen from N,N-Bis(2-ethylhexyl)-1,2,4-triazol-1-ylmethanamine (CAS 91273-04-0) and N,N′-bis-(2-ethylhexyl)-4-methyl-1H-benzotriazole amine (CAS 80584-90-3), alone or in a mixture and the passivators described on page 5 of US2006/0272597 cited by way of example and the content of which is incorporated by way of reference. In particular, the metal passivator is advantageously chosen from N,N-bis(2-ethylhexyl)-1,2,4-triazol-1-ylmethanamine (CAS 91273-04-0) and N,N′-bis-(2-ethylhexyl)-4-methyl-1H-benzotriazole amine (CAS 80584-90-3), alone or in a mixture.
According to the nature and the miscibility of constituents a) to i) of the additive composition according to the invention, with gas oil, the additive composition can also contain one or more hydrocarbon organic solvents and optionally at least one compatibilizing agent or co-solvent. Preferably, the additive composition also comprises at least one hydrocarbon organic solvent and/or at least one compatibilizing agent or co-solvent. The metal deactivator(s) or chelating agents a) can be chosen from amines substituted by N,N′-disalicylidene groups, such as N,N′-disalicylidene 1,2-diaminopropane (DMD).
The antioxidant or antioxidants b) can be chosen from molecules comprising at least one hindered phenol group (alkylphenols), alone or in a mixture; as examples of antioxidants of the hindered phenol type, there can be mentioned di-t-butyl-2,6 methyl-4 phenol (BHT), t-butyl hydroquinone (TBHQ), 2,6 and 2,4 di-t-butyl phenol, 2,4-dimethyl-6-t-butyl phenol, pyrogallol, tocopherol, 4,4′-methylene bis(2,6-di-t-butyl phenol) (CAS No. 118-82-1), alone or in a mixture.
The dispersant(s) c) can for example be chosen from:
where R1 represents a polyisobutene group with a molecular mass comprised between 140 and 5000 and preferably between 500 and 2000 or, preferably, between 750 and 1250;
where:
R is an alkyl group comprising from 1 to 30 carbon atoms;
R1 and R2 are each independently a hydrogen atom, an alkyl chain of from 1 to 6 carbon atoms or —O—CHR1-CHR2-;
A is an amine or N-alkylamine with 1 to 20 carbon atoms in the alkyl chain, an N,N-dialkylamine having from 1 to 20 carbon atoms in each alkyl group, or a polyamine with 2 to 12 nitrogen atoms and 2 to 40 carbon atoms.
and x ranging from 5 to 100;
Such polyetheramines are for example marketed by BASF, HUNTSMAN or CHEVRON.
The optional acid neutralizer(s) or scavenger(s) d) can be chosen, from the aliphatic, cycloaliphatic and aromatic amines. Preferably, it is preferred to use dimethylcyclohexyldiamine as acidity neutralizer. The low-temperature performance additive or additives e) can be chosen from additives improving the pour point, additives improving the cold filter plugging point (CFPP), additives improving the cloud point and/or the anti-sedimentation additives and/or paraffin dispersants. As examples of additives improving the pour-point and filtrability (CFIs), there can be mentioned the ethylene and vinyl acetate (EVA) copolymers and/or ethylene and vinyl propionate (EVP) copolymers.
As examples of additives improving the CFPP, there can be mentioned the multi-functional cold operability additives chosen from particular from the group constituted by the polymers based on olefin and alkenyl nitrate such as those described in EP 573 490. As examples of additives improving the cloud point, there can be mentioned non-limitatively the compounds chosen from the group constituted by the long-chain olefin/(meth)acrylic ester/maleimide terpolymers, and fumaric/maleic acid ester polymers. Examples of such additives are given in EP 71 513, EP 100 248, FR 2 528 051, FR 2 528 423, EP1 12 195, EP 1 727 58, EP 271 385 and EP 291367. As examples of anti-sedimentation additives and/or paraffin dispersants, it is possible to use in particular anti-sedimentation (but non-limitatively) additives chosen from the group constituted by the (meth)acrylic acid/polyamine-amidified alkyl (meth)acrylate copolymers, polyamine alkenylsuccinimides, phthalamic acid and double-chain fatty amine derivatives; alkylphenol/aldehyde resins. Examples of such additives are given in EP 261 959, EP593 331, EP 674 689, EP 327 423, EP 512 889, EP 832 172; US 2005/0223631; U.S. Pat. No. 5,998,530; WO 93/14178.
Preferably, the additive compositions according to the invention contain ethylene/vinyl acetate (EVA) copolymers and/or ethylene/vinyl acetate/vinyl versatate (VEOVA) terpolymers and/or ethylene/vinyl acetate/acrylic ester (2-ethylhexyl acrylate) terpolymers as low-temperature additive e).
The optional marker(s) or tracer(s) f) can in particular be chosen from the following aliphatic or cycloaliphatic esters:
The optional fragrancing agent(s) or agent(s) for masking odours and/or reodorant(s) g) can be chosen from:
in which the cyclopentane ring is saturated or unsaturated, and R1, R2, R3, identical or different, are chosen from hydrogen and the hydrocarbon radicals comprising from 1 to 10 carbon atoms and optionally comprising one or more heteroatoms as well as
The biocide(s) h) can be chosen from:
Preferably, the additive composition according to the invention comprises:
According to a particularly preferred embodiment, the additive composition according to the invention comprises:
a) at least one metal-sequestering agent chosen from the amines substituted by N,N′-disalicylidene groups, such as N,N′-disalicylidene 1,2-diaminopropane (DMD),
b) at least one antioxidant of the hindered phenol type, chosen from the molecules comprising at least one hindered phenol group, alone or in a mixture; as examples of antioxidants of the hindered phenol type, there can be mentioned di-t-butyl-2,6 methyl-4 phenol (BHT), t-butyl hydroquinone (TBHQ), 2,6 or 2,4 di-t-butyl phenol, 2,4-dimethyl-6-t-butyl phenol, pyrogallol, tocopherol, 4,4′-methylene bis(2,6-di-t-butyl benol) (CAS No. 118-82-1), alone or in a mixture, and from the molecules generally,
c) at least one dispersant and/or detergent, chosen preferably from the PIBSIs,
d) at least one acidity neutralizer of the amine type,
i) at least one metal passivator i) chosen from the amines substituted by triazole groups, such as benzotriazole, toluoyltriazole, and optionally
e) at least one additive for improving low-temperature performance chosen from the EVA copolymers and/or VEOVA terpolymers,
f) at least one marker or tracer,
h) at least one biocide additive, and/or
g) at least one fragrancing agent and/or agent for masking odours and/or reodorant, chosen from:
in which the cyclopentane ring is saturated or unsaturated, and R1, R2, R3, identical or different, are chosen from hydrogen and the hydrocarbon radicals comprising from 1 to 10 carbon atoms and optionally comprising one or more heteroatoms
as well as
Apart from the components described previously, the additive composition according to the invention can contain, apart from the additive(s) according to the invention, one or more other additives, different from the constituents a) to i), and solvent(s) and/or co-solvents such as for example markers other than those corresponding to the definition of the markers e) and in particular the markers mandated by regulations, for example the Red dye at present required by the regulations in non-road gas oil and domestic fuel oil, demulsifiers; the anti-static or conductivity improving additives; lubricity additives, anti-wear agents and/or friction modifiers, additives for improving combustion and in particular cetane improving additives, anti-foaming additives etc.
Preferably, the additive compositions according to the invention comprise:
According to a second subject, the invention relates to a method for the preparation of the additive compositions as defined above, by mixing, preferably at ambient temperature, components a) to c), and optionally e) to i) of said compositions and/or solvent(s) and/or compatibilizing agent(s), in one or more steps by any suitable mixing means. According to a particular embodiment, the method for the preparation of the additive compositions as defined above, is carried out by mixing, preferably at ambient temperature, components a) to c) and compound i), and optionally e) to h) of said compositions and/or solvent(s) and/or compatibilizing agent(s), in one or more steps by any suitable mixing means. When the additive compositions according to the invention also comprise solvent(s) and/or co-solvent, they can be prepared in the same way, by mixing the components in one or more steps. The additive compositions according to the invention have the additional advantage of being stable in storage for at least several months at temperatures generally ranging from −15° C. to +40° C. and can therefore be stored, for example in a depot, at the refinery, before being mixed with standard gas oil or non-road gas oil.
According to a third subject the invention relates to a liquid fuel composition of the gas oil type comprising:
By “fuel” is meant a fuel which powers an internal combustion engine. In particular, a liquid fuel of the gas oil type is considered to be a fuel which powers a diesel type engine. By “majority part” is meant the fact that the liquid fuel composition of the gas oil type comprises at least 50% by mass of the mixture based on liquid hydrocarbons.
The mixture based on liquid hydrocarbons is, advantageously, constituted by any mixture of hydrocarbons capable of being used as diesel fuel. Diesel fuels generally comprise hydrocarbon cuts having a distillation range (determined according to the standard ASTM D 86) comprised between 150 and 380° C., with an initial boiling point comprised between 150 and 180° C. and a final boiling point comprised between 340 and 380° C. The density at 15° C. of the gas oils is in a standard fashion comprised between 0.810 and 0.860.
According to a particular embodiment, the liquid fuel composition of the gas oil type can comprise a product of renewable origin such as fatty acid esters. The renewable product content in the liquid fuel composition of the gas oil type is, advantageously, at least 0.2% by mass. The liquid fuel composition of the gas oil type can comprise at least seven parts by volume of at least one product of renewable origin. The product of renewable origin is chosen from the fatty acid esters, essentially or exclusively of animal or vegetable origin. The fatty acid esters are advantageously fatty acid methyl esters (FAMEs), essentially or exclusively of vegetable or animal origin, for example vegetable and/or animal oil esters, in particular vegetable oil methyl esters or VOMEs.
Preferably, the liquid fuel composition of the on-road or non-road gas oil type according to the invention comprises from 100 to 2000 ppm, preferably from 250 to 1500 ppm, more preferentially from 250 to 1000 ppm by mass of additive composition(s) as defined above. The other optional additives are generally incorporated in quantities ranging from 50 to 1500 ppm by mass. As examples of other optional additives, there can be mentioned, non-limitatively, lubricity or anti-wear additives, combustion improvers, anti-foaming agents, anticorrosion agents, detergents etc.
The liquid fuel compositions of the gas oil type according to the invention can be prepared by mixing the liquid fuel, additive composition(s) according to the invention and other optional additive(s), in one or more steps, generally at ambient temperature. The scope of the invention would not be exceeded by separately mixing the components of the additive composition according to the invention (additives a) to c)), optionally additives d) to i), the solvent(s) and/or co-solvent(s)), the other optional additives (in the form of a package or not) with the fuel of the gas oil type.
According to a fourth subject, the invention relates to the use of the additive compositions as described above as an agent for improving storage stability, oxidation resistance, low-temperature performance and, more particularly, engine performances in particular reduction in fouling (fouling and clogging) by gas oil fuels, in particular, by non-road gas oil fuels.
The invention also relates to the use of the gas oil-based liquid fuel compositions according to the invention as defined above as higher-grade fuels of the gas oil type, i.e. having storage stability properties and, towards materials, oxidation resistance, low-temperature performance and, more particularly, engine performances in particular a reduction in fouling (fouling and clogging) greater than that of a standard grade on-road and non-road gas oil (which, as a minimum, meets the specifications of the standard EN 590).
The higher grade gas oil according to the invention, i.e. comprising at least one additive composition according to the invention, can be advantageously used as fuel for the engines of the non-road machinery listed in the Decree of 10/12/10, namely
The characteristics of non-road gas oils in compliance with the decree of 10 Dec. 2010, i.e. of standard grade non-road gas oils, are listed in Tables 1 and 2 below.
Several additive compositions are prepared by mixing at ambient temperature several of the components listed below in proportions shown in Table 3
The viscosity of the additive compositions F3 and F5 at 20, 40 and −10° C. is measured according to the standard NF EN ISO 3104, as well as their storage stability over time according to the method described in detail below:
The results are shown in Table 4 below.
Injector fouling tests according to the XUD9 procedure were carried out on 5 compositions of non-road gas oil B7 comprising respectively the compositions F1 to F5 of Example 1, as well as on the same pure non-road gas oil B7 evaluated at the start and at the end of the series so as provide a context for the results and verify the stability of the engine.
The fouling test implemented has the following characteristics:
The objective of this test is to evaluate the performance of the fuels and/or of additive compositions towards the fouling of the injectors on a four-cylinder Peugeot XUD9 A/L engine with indirect diesel injection.
The test was started with a four-cylinder Peugeot XUD9 NL engine with indirect diesel injection equipped with clean injectors the flow rate of which was determined beforehand. The engine follows a defined test cycle for 10 hours and 3 minutes (repetition of the same cycle 134 times). At the end of the test, the flow rate of the injectors is again evaluated. The quantity of fuel required for the test is 45 L. The loss of flow rate is measured on the four injectors. The results are expressed as a percentage of loss of flow rate for different needle lifts. Usually the fouling values at 0.1 mm of needle lift are compared as they are more discriminatory and more accurate and repeatable (repeatability <5%).
The non-road gas oil containing 7% (vol/vol) or (v/v) of FAME and corresponding to the standard EN590 for tested pure gas oil shows a level of fouling of the order of 70% (72% at the start and 70.4% at the end of the series). All the tested compositions containing additives show a level of fouling ranging from 60.7 to 70.5%, therefore equivalent to or less than that of the pure non-road gas oil B7 tested. The best cases measured show a gain greater than or equal to 10%.
It is noted that the compositions F1, F3, F4 and F5 are more effective in limiting the fouling of the XUD9 injectors.
The oxidation stability of compositions of non-road gas oil B7 (GOM B7) comprising one of the additive compositions F1 to F5 was measured according to the Rancimat method (standard EN15751) and, by way of comparison, that of the non-road gas oil without additives was also measured. The results are shown in Table 6.
It is noted that the presence of additives in non-road gas oil makes it possible to improve the induction period (gain from 10 to >38 hours compared with the fuel without additives). The oxidation stability of compositions of non-road gas oil B7 comprising one of the additive compositions Fi was measured according to the method described in detail in the standard ISO 12205 (gum content) and according to the method described in detail in the standard ISO 6618 (acid number variation). The results relating to gum formation are shown in Table 7 and those relating to the acid number are shown in Table 8.
It is noted that non-road gas oils comprising the compositions F1 to F5 have limited gum content variation and acid number variation compared with gas oil without additives. The formulations F3 and F5 are the most effective in limiting gum formation (Table 7). As regards the acid number variation, it is noted that the compositions F1 and F3 are the most effective for limiting the development of acidity (Table 8).
The effectiveness of the resistance to contact with metals of the non-road gas oil compositions with or without an additive composition Fi added was measured according to the method described in detail below:
a metal plate of zinc or copper is brought into contact with 100 mL of the fuel in a 125 mL glass flask; the metal strip is completely immersed for 7 days at ambient temperature (approximately 20° C.). The metal surface area in contact with the fuel is 10 cm2. After this period of contact, the copper or zinc metals which are present in the fuel are assayed. The results are shown in Table 9 below.
GOM B7 tested: GOM EN 590 having been used for soaking a strip of Cu and a strip of Zn for 7 days at 20° C. It is noted that the compositions F2; F3 and F5 are the most effective in limiting the dissolution of the copper and of the zinc.
Oxidation stability tests according to the Rancimat method (standard EN15751) are carried out on the fuel compositions brought into contact beforehand with metals such as zinc or copper as described in Example 4. The results obtained according to the Rancimat method show a degradation of the stability of the GOM B7 compared with stability tests on fuels which have not been brought into contact with the metals of Example 3. The results are shown in Table 10 below.
It is noted that the fuel with F3 added is the most effective (highest induction period).
The cold filter plugging point according to the standard NF EN 116 of several EN 590 non-road gas oils of type B0 (without FAME) or B7 (with 7% vol./vol. of FAME), with or without 1000 ppm v/v of the composition F3 added, was measured. The CFPP gain was also measured with respect to the same gas oil without additives. The results are shown in Table 11.
It is noted that according to the gas oils tested, the composition F3 makes it possible to improve the CFPP with a gain of 4 at 15° C. with an additive content of 1000 ppm vol./vol.
Injector fouling tests according to the CEC DW10 procedure referenced SG-F-098 were carried out on a gas oil composition B7 corresponding, as a minimum, to the specification EN 590 comprising the composition F3 of Example 1, denoted G1, as well as on the same composition of pure gas oil B7, denoted G0, evaluated at the start and at the end of the series so as to provide a context for the results and verify the stability of the engine. The test uses a DW10BTED4 engine developed by PSA Peugeot Citroen, having a cylinder capacity of 1998 cm3, with direct diesel injection, in compliance with the Euro 4 emission standards if the vehicle is equipped with a particulate trap. Table 12 summarizes the main characteristics of the engine:
The fouling test implemented has the following characteristics: The fouling procedure lasts 32 hours. The 32 hours are divided into four 8-hour periods interspersed with periods of maceration, each lasting 4 hours, during which the engine is stopped. In order to accelerate the fouling of the injectors, 1 ppm of zinc by mass in the form of zinc neodecanoate of formula Zn(C10H19O2)2 is added to the fuel.
The test evaluates the loss of power of the engine after running for 32 hours. A slight loss of power reflects slight fouling. The additive composition is therefore judged by its non-fouling nature and its ability to prevent deposits when it is introduced into the fuel in the presence of zinc.
At each cycle, the value of the power on the twelfth stroke (4000 rpm fully loaded) is measured. The test result is the loss of power measured at this point between the end of the test (linear average of the last 5 measurements) and the start of the test (linear average of the first 5 measurements).
Consequently, these results show that the gas oil composition G1 according to the invention has a non-fouling nature. Moreover, the additive composition F3 is remarkable in that it has a high capability for preventing deposits when it is introduced into a gas oil fuel in the presence of zinc.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1156363 | Jul 2011 | FR | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP2012/063532 | 7/11/2012 | WO | 00 | 1/9/2014 |
