US20170183594A1

US20170183594A1 - Low-viscosity lubricating polyolefins

Info

Publication number: US20170183594A1
Application number: US15/313,605
Authority: US
Inventors: Marion COURTIADE; Julien SANSON; Alexandre Welle; Martine Slawinski; Jeroen Wassenaar
Original assignee: Total Marketing Services SA
Current assignee: TotalEnergies Marketing Services SA
Priority date: 2014-05-30
Filing date: 2015-05-29
Publication date: 2017-06-29
Also published as: EP3149122A1; FR3021664B1; CN106414680A; CA2950123A1; MX2016015518A; ZA201608165B; WO2015181358A1; MA39911A; KR20170010778A; JP2017519097A; FR3021664A1

Abstract

Disclosed is a low-viscosity oil including more than 50 wt % of 9-methyl-11-octyl-heneicosane as well as a lubricating composition including the base oil and optionally another base oil or an additive. The oil has a kinematic viscosity at 100° C., measured according to standard ASTM D445, ranging from 3 to 4 mm²/s⁻¹. Also disclosed is such a low-viscosity oil prepared according to a specific method using a metallocene catalyst as well as the use of the oil as a high-performance lubricant for lubrication in the fields of engines, gears, brakes, hydraulic fluids, coolants and greases.

Description

The invention relates to a low-viscosity oil comprising more than 50 weight % of 9-methyl-11-octyl-henicosane, and to a lubricating composition comprising this base oil and optionally another base oil or an additive. This oil of the invention has kinematic viscosity at 100° C., measured according to standard ASTM D445, ranging from 3 to 4 mm².s⁻¹.
The invention also concerns said low-viscosity oil prepared following a particular method using a metallocene catalyst, and the use of the oil as high-performance lubricant in sectors relating to engines, gears, brakes, hydraulic fluids, coolants and greases.
In the API classification of base oils, polyalphaolefins (PAOs) are referenced as base oils of group IV. Having a good compromise between viscosity, volatility and cold start properties, these PAOs are increasingly more used in top performing lubricant formulas. In particular, this better compromise is highly advantageous in comparison with mineral bases of group III.
In general, PAOs are synthesised from different olefin monomers, in particular from C₆to C₁₄monomers, via acid catalysis or in the presence of a metallocene catalyst. In general, to prepare low-viscosity products of grades ranging from 2 to 10, use is made of acid catalysts.
Methods are known for preparing PAOs via metallocene catalysis generally leading to products of high viscosity with kinematic viscosity at 100° C., measured according to standard ASTM D445, ranging from 40 to 150 mm².s⁻¹(grades 40 to 150).
There are increasing needs for high performance lubricants. In particular, such needs are due to conditions of use of increasing severity e.g. very high temperatures or mechanical stresses.
The time between oil changes and the reduction in the size of lubricating systems also lead to an increased need for high-performance lubricants.
Energy efficiency and in particular the improved Fuel Eco (FE) of lubricants or the reduction in the fuel consumption of engines, vehicle engines in particular, are objectives of ever greater importance and lead to the increasing use of high-performance lubricants.
High-performance lubricants must therefore have improved properties, in particular regarding kinematic viscosity, viscosity index, volatility, cold cranking viscosity or cold pour point.
Thermal stability and resistance to oxidation are also properties to be improved for high-performance lubricants.
Reduced toxicity and good miscibility with other lubricants or other materials are also properties to be sought for high-performance lubricants.
Additionally, improved methods to prepare PAOs must also be developed in particular to improve the yield or selectivity of these methods.
Improved catalytic activity is another target.
The methods for preparing PAOs should also allow the recycling of all or part of the by-products derived from oligomerisation reactions.
The methods for preparing PAOs should also allow control over molar mass and polydispersity index as well as the distribution of the formed PAOs.
An improvement in the characterization techniques of the different products formed during the synthesis of PAOs is also to be sought, in particular when qualitatively or quantitatively analysing the formed products.
WO-2013/055480 describes the preparation of PAOs that can be used as lubricants for vehicle engines. This document describes a lubricating composition comprising said oil associated with another base oil and with an additive improving the viscosity index. However, this patent application does not disclose 9-methyl-11-octyl-henicosane, or the particular properties thereof.
EP-1 950 278 discloses an engine lubricating composition particularly comprising a saturated oligomer of olefins obtained via metallocene catalysis. However, this patent application does not disclose 9-methyl-11-octyl-henicosane or the particular properties thereof.
WO-2007/01973 describes the catalytic preparation of PAOs. This patent application describes the use of non-bridged metallocene catalysts. This document does not describe the preparation of 9-methyl-11-octyl-henicosane or the particular properties thereof.
WO-2007/011459 describes PAOs obtained from the polymerisation of C₅-C₂₄-olefins. This patent application does not disclose 9-methyl-11-octyl-henicosane, or the particular properties thereof.
WO-02/14384 describes a method to polymerise olefins via metallocene catalysis.
The described method only uses fluoro-cyclopentadienyl catalysts. This document des not describe the preparation of 9-methyl-11-octyl-henicosane.
WO-89/12662 describes a liquid lubricating composition containing C₃₀-C₃₀₀hydrocarbons having a methyl/methylene group ratio lower than 0.19. This document does not disclose a proportion higher than 50 weight % of 9-methyl-11-octylheneicosane contained in an oil.
EP-283922 concerns a mixture comprising a polysiloxane and hydrogenated PAO.
The disclosed product Synfluid 4 cS does not contain a proportion higher than 50 weight % of 9-methyl-11-octylheneicosane in an oil.
There is therefore a need for high-performance lubricants allowing a solution to be found for all or part of lubricant problems in the prior art.
The invention therefore provides an oil having kinematic viscosity at 100° C., measured in accordance with standard ASTM D445, ranging from 3 to 4 mm².s⁻¹, comprising more than 50 weight % of 1-decene trimer of formula (I)
The oil of the invention has particularly advantageous kinematic viscosity ranging from 3 to 4 mm².s⁻¹. More advantageously, the kinematic viscosity of the oil of the invention ranges from 3.2 to 3.8 mm².s⁻¹. Preferably, the kinematic viscosity of the oil of the invention is 3.4 mm².s⁻¹, 3.5 mm².s⁻¹or 3.6 mm².s⁻¹.
Also advantageously, the oil of the invention has a viscosity index higher than 120 or between 120 and 140 or between 125 and 135. Preferably, the viscosity index of the oil of the invention is 130 or higher.
In general, according to the invention, the viscosity index is calculated in accordance with standard ASTM D2270.
Also advantageously, the oil of the invention has volatility measured according to standard ASTM D6375 lower than 10.8% by mass. Preferably, the volatility of the oil of the invention is lower than 10.5% by mass.
Also advantageously, the oil of the invention has cold cranking viscosity (CCS) at −35° C., measured in accordance with standard ASTM D5293, lower than 900 mPa·s. Preferably, the cold cranking viscosity of the oil of the invention is lower than 800 mPa·s. According to the invention, the cold cranking viscosity of the oil of the invention is measured on a rotating dynamic viscometer (CCS cold cranking simulator).
Also advantageously, the oil of the invention has a mean molecular mass ranging from 300 to 1 000 g/mol, preferably from 350 to 450 g/mol. In general, in the invention the mean molecular mass is calculated in accordance with standard ASTM D2502.
Also advantageously, the oil of the invention has a pour point of −50° C. or lower, preferably of −55 or −57° C. or lower. In general, according to the invention the pour point is measured according to standard EN ISO 3016.
Advantageously, the invention provides an oil combining:

- (a) kinematic viscosity at 100° C., measured according to ASTM D445 ranging from 3.2 to 3.8 mm².s⁻¹.
- (b) viscosity index higher than 120;
- (c) volatility measured according to standard ASTM D6375 lower than 10.8% by mass; and
- (d) cold cranking viscosity (CCS) at −35° C., measured according to standard ASTM D5293 lower than 900 mPa·s.

Also advantageously, the invention provides an oil combining these properties: (a) and (b); (a) and (c); (a) and (d); (b) and (c); (b) and (d); (c) and (d); (a), (b) and (c); (a), (b) and (d); (a), (c) and (d); (b), (c) and (d).
Preferably, the invention provides an oil combining:

- (a) kinematic viscosity at 100° C., measured according to standard ASTM D445, of 3.4 mm².s⁻¹, 3.5 mm².s⁻¹or 3.6 mm².s⁻¹;
- (b) viscosity index of 130 or higher;
- (c) volatility measured according to standard ASTM D6375 lower than 10.5% by mass; and
- (d) cold cranking viscosity (CCS) at −35° C., measured according to standard ASTM D5293, lower than 900 mPa·s.

Also preferably, the invention provides an oil combining these properties: (a) and (b); (a) and (c); (a) and (d); (b) and (c); (b) and (d); (c) and (d); (a), (b) and (c); (a), (b) and (d); (a), (c) and (d); (b), (c) and (d).
Advantageously, the oil of the invention comprises at least 65 weight % of 1-decene trimer of formula (I) or at least 70 weight % of 1-decene trimer of formula (I). More advantageously, the oil of the invention comprises at least 80 weight % of 1-decene trimer of formula (I) or at least 90 weight % of 1-decene trimer of formula (I). Preferably, the oil of the invention comprises 50 to 99 weight % of 1-decene trimer of formula (I). More preferably, the oil of the invention comprises 60 to 90 weight % of 1-decene trimer of formula (I). Further preferably, the oil of the invention comprises 70 to 90 weight % of 1-decene trimer of formula (I).
Also preferably, the oil of the invention comprises 60 to 95 weight %, 60 to 80 weight %, 70 to 95 weight %, 70 to 80 weight %, 75 to 95 weight % or 75 to 80 weight % of 1-decene trimer of formula (I).
In addition to thel-decene trimer of formula (I), the oil of the invention may comprise other oligomers derived from oligomerisation of 1-decene.
For example, the oil of the invention may comprise at least one other saturated oligomer of 1-decene. Preferably, this other saturated oligomer of 1-decene can be selected from among the other saturated trimers of 1-decene. It can also be selected from a wider group of saturated oligomers comprising the dimers of 1-decene, the other trimers of 1-decene, the tetramers of 1-decene, the pentamers of 1-decene.
Preferably, the oil of the invention may also comprise at least one other saturated oligomer of 1-decene selected from among 9-methyl-nonadecane and 9-methyl-11,13-dioctyl-tricosane.
Additionally, the oil of the invention may comprise other oligomers of 1-decene of larger size.
Particularly advantageously, the oil of the invention comprises:

- 51 to 99.9 weight %, preferably 70 to 90 weight % of 1-decene trimer of formula (I) and
- 0.1 to 49 weight %, preferably 10 to 30 weight % of at least one other saturated trimer of 1-decene.

Also advantageously, the oil of the invention comprises:

- 51 to 99.6 weight % of 1-decene trimer of formula (I);
- 0.1 to 1 weight % of at least one saturated dimer of 1-decene, e.g. 9-methyl-nonadecane;
- 0.1 to 25 weight % of at least one other saturated trimer of -decene;
- 0.1 to 20 weight % of at least one saturated tetramer of 1-decene, e.g. 9-methyl-11,13-dioctyl-tricosane;
- 0.1 to 1.5 weight % of at least one saturated pentamer of 1-decene.

As essential characteristic, the oil of the invention comprises more than 50 weight % of 9-methyl-11-octyl-henicosane. Preferably, the oil of the invention comprising more than 50 weight % of 9-methyl-11-octyl-henicosane is prepared following a method comprising:

- oligomerisation of 1-decene in the presence of hydrogen (H₂), a metallocene catalyst and an activator compound, or in the presence of hydrogen (H₂), a metallocene catalyst, an activator compound and co-activator compound;
- catalytic hydrogenation of the oligomerisation products in the presence of hydrogen(H₂) and a catalyst selected from among a hydrogenation catalyst and palladium-containing hydrogenation catalyst;
- separation, by distillation at reduced pressure, of the fraction of trimers comprising more than 50 weight % of 1-decene trimer of formula (I)

Preferably, the oligomerisation of 1-decene is performed in the presence of a metallocene catalyst which is a racemic compound of formula (II)
L(Q¹)(Q²)MR¹R² (II)

- where:
- M is a transition metal selected from among titanium, zirconium, hafnium and vanadium, or is zirconium;
- Q¹an Q², substituted or unsubstituted are independently a cyclic tetrahydroindenyl group, or Q¹and Q²are independently a cyclic tetrahydroindenyl group and are bonded to formed a polycyclic structure;
- L is a Q¹and Q²bridging C₁-C₂₀divalent alkyl group, or L is a group selected from among methylene (—CH₂—), ethylene (—CH₂—CH₂—), methylmethylene (—CH(CH₃)—), 1-methyl-ethylene (—CH(CH₃)—CH₂—), n-propylene (—CH₂—CH₂—CH₂—), 2-methylpropylene (—CH₂—CH(CH₃)—CH₂—), 3-methylpropylene (—CH₂—CH₂—CH(CH₃)—), n-butylene (—CH₂—CH₂—CH₂—CH₂—), 2-methylbutylene (—CH₂—CH(CH₃)—CH₂—CH₂—), 4-methylbutylene (—CH₂—CH₂—CH₂—CH(CH₃)—), pentylene and isomers thereof, hexylene and isomers thereof, heptylene and isomers thereof, octylene and isomers thereof, nonylene and isomers thereof, decylene and isomers thereof, undecylene and isomers thereof, dodecylene and isomers thereof;
- R¹and R², substituted or unsubstituted, are independently an atom or group selected from among hydrogen, halogens (such as Cl and I), alkyl (such as Me, Et, nPr, iPr), alkenyl, alkynyl, haloalkyl, haloalkenyl, haloalkynyl, silylalkyl, silylalkenyls, silylalkynyls, germylalkyl, germylalkenyl, germylalkynyl; or R¹and R²together with M form a metallocycle comprising 3 to 20 carbon atoms.

More preferably, the metallocene catalyst is a racemic compound of formula (II) where:

- M is zirconium;
- Q¹and Q², substituted or unsubstituted, are independently a cyclic tetrahydroindenyl group;
- L is a group selected from among methylene (—CH₂—), ethylene (—CH₂—CH₂—), methylmethylene (—CH(CH₃)—), 1-methyl-ethylene (—CH(CH₃)—CH₂—), n-propylene (—CH₂—CH₂—CH₂—), 2-methylpropylene (—CH₂—CH(CH₃)—CH₂—), 3-methylpropylene (—CH₂—CH₂—CH(CH₃)—), n-butylene (—CH₂—CH₂—CH₂—CH₂—), 2-methylbutylene (—CH₂—CH(CH₃)—CH₂—CH₂—), 4-methylbutylene (—CH₂—CH₂—CH₂—CH(CH₃)—), pentylene and isomers thereof, hexylene and isomers thereof, heptylene and isomers thereof, octylene and isomers thereof, nonylene and isomers thereof, decylene and isomers thereof, undecylene and isomers thereof, dodecylene and isomers thereof;
- R¹and R², substituted or unsubstituted, are independently a halogen atom e.g. Cl and I, or an alkyl group such as Me, Et, nPr, iPr.

Further preferably, the metallocene catalyst is selected from among rac-ethylene bis(tetrahydroindenyl) zirconium dimethyl and rac-ethylene bis(tetrahydroindenyl)zirconium dichloride, in particular rac-ethylene bis(tetrahydroindenyl) zirconium dimethyl.
For the method of the invention, the catalyst is used in activated form for oligomerisation of 1-decene. Therefore, the method of the invention uses an activator compound for oligomerisation of 1-decene.
Advantageously the activator compound is selected from among an alumoxane, an ionic activator and mixtures thereof.
Preferably, for the method of the invention, the alumoxane is an oligomeric compound comprising residues of formula —Al(R)—O— where R is independently a cyclic or straight-chain C₁-C₂₀alkyl group. Preferably, the alumoxane is selected from among methylalumoxane, modified methylalumoxane, ethylalumoxane, isobutylalumoxane and mixtures thereof.
Also preferably, the alumoxane is used with an alumoxane/catalyst molar ratio ranging from 1 to 10 000, preferably ranging from 10 to 3 000 and more preferably from 100 to 1 500.
Preferably, for the method of the invention, the activator compound is an ionic activator. The ionic activator can be selected from among dimethylanilinium tetrakis-(perfluorophenyl)borate (DMAB), triphenylcarbonium tetrakis-(perfluorophenyl)borate, dimethylanilinium tetrakis-(perfluorophenyl)aluminate and mixtures thereof. More preferably, the ionic activator is dimethylanilinium tetrakis-(perfluorophenyl)borate (DMAB).
Also preferably, the ionic activator is used in a molar ratio of ionic activator/catalyst ranging from 0.5 to 4, preferably from 0.8 to 1.2.
For oligomerisation of 1-decene, the method of the invention uses an activator compound. It may also be advantageous to use a co-activator compound, in particular when using an ionic activator.
Preferably, the co-activator compound is a trialkylaluminium derivative. More preferably, the co-activator compound is selected from among tri-ethyl aluminium (TEAL), tri-iso-butyl aluminium (TIBAL), tri-methyl aluminium (TMA), tri-n-octyl aluminium and methyl-methyl-ethyl aluminium (MMEAL). Advantageously, tri-iso-butyl aluminium (TIBAL) is used in the form of a dispersion possibly ranging from 10 to 60 weight %.
Also preferably, the co-activator compound is used in a molar ratio of co-activator compound/catalyst ranging from 10 to 1 000, preferably 20 to 200.
Advantageously, the metallocene catalyst and the activator compound, optionally in the presence of a co-activator compound, are contacted at a pressure of 1 bar and at a temperature of 20° C.
Advantageously, the oligomerisation of 1-decene is conducted over a time ranging from 2 to 300 min. Preferably, the oligomerisation time ranges from 5 to 180 min, in particular 30 to 140 min.
Also advantageously, the oligomerisation of 1-decene is performed in the presence of hydrogen (H₂) at partial pressure ranging from 0.1 to 20 bar. Preferably, the partial hydrogen pressure (H₂) ranges from 1 to 6 bar.
Also advantageously, oligomerisation is performed in a weight ratio of hydrogen/1-decene higher than 100 ppm or lower than 600 ppm. Preferably, this ratio is between 100 and 600 ppm.
Also advantageously, oligomerisation of 1-decene is conducted at a temperature ranging from 50 to 200° C., preferably 70 to 160° C. More preferably, the temperature for oligomerisation of 1-decene ranges from 80 to 150° C. and further preferably from 90 to 140° C. or from 100 to 130° C.
Oligomerisation of 1-decene can be performed in the 1-decene, that is then used as substrate for the reaction. The reaction is then advantageously conducted without any solvent.
Oligomerisation of 1-decene can also be conducted in a solvent. Preferably, the solvent can be selected from among a straight-chain or branched hydrocarbon, cyclic or non-cyclic hydrocarbon, an aromatic alkylated compound and mixtures thereof. As preferred solvents for oligomerisation of 1-decene, it is preferred to use a solvent selected from among butanes, pentanes, hexanes, heptanes, octanes, cyclopentane, cyclohexane, methylcyclopentane, methylcyclohexane, methylcycloheptane, toluene, xylene and mixtures thereof.
After oligomerisation of 1-decene, the method of the invention applies catalytic hydrogenation of the oligomerisation products. The catalytic hydrogenation of oligomerisation products is performed in the presence of hydrogen (H₂) and a hydrogenation catalyst.
Preferably, the hydrogenation catalyst is selected from among a derivative of palladium, a derivative of supported palladium, a derivative of alumina-supported palladium (e.g. on gamma-alumina), a derivative of nickel, a derivative of supported nickel, a derivative of kieselguhr-supported nickel, a derivative of platinum, a derivative of supported platinum, a derivative of cobalt-molybdenum, a derivative of supported cobalt-molybdenum.
More preferably, the hydrogenation catalyst comprises palladium. One particularly preferred hydrogenation catalyst comprises alumina-supported palladium (e.g. on gamma-alumina).
Also preferably, the pressure of hydrogen (H₂) for catalytic hydrogenation of the oligomerisation products ranges from 5 to 50 bar, more preferably from 10 to 40 bar, in particular from 15 to 25 bar.
After oligomerisation of 1-decene and catalytic hydrogenation of the oligomerisation products, the method of the invention comprises separation via distillation at reduced pressure of the fraction of trimers comprising more than 50 weight % of 1-decene trimer of formula (I).
Separation via distillation is conducted at reduced pressure. Advantageously, separation via distillation is performed in accordance with standard ASTM D2892 or with standard ASTM D5236.
More advantageously, separation is performed in two steps: via distillation according to standard ASTM D2892 followed by distillation according to standard ASTM D5236. Preferably, when separating via distillation according to standard ASTM D2892, the initial boiling point (IBP) is lower than 370° C., preferably lower than 375° C. The partial pressure is advantageously lower than 0.67 mBar (0.5 mmHg).
Distillation in accordance with ASTM D2892 allows the separation of products having a boiling point lower than these temperatures.
Preferably, when separating by distillation in accordance with standard ASTM D5236, the initial boiling point (IBP) is between 360 and 485° C., preferably between 370 and 480° C. or between 370 and 470° C. More preferably, the initial boiling point is between 375 and 465° C. when separating via distillation according to standard ASTM D5236. The partial pressure is advantageously lower than 0.67 mBar (0.565 mmHg).
Preferably, separation by distillation according to standard ASTM D5236 allows separation of the fraction of trimers comprising more than 50 weight % of 1-decene trimer of formula (I).
Therefore, separation via distillation at reduced pressure allows separation of the fraction of trimers derived from oligomerisation of 1-decene, followed by hydrogenation of the oligomerisation products. This trimer fraction comprises more than 50 weight % of 1-decene trimer of formula (I).
In addition to the steps of 1-decene oligomerisation, catalytic hydrogenation of the oligomerisation products and separation via distillation at reduced pressure of the trimer fraction comprising more than 50 weight % 1-decene trimer of formula (I), the method of the invention can advantageously comprise other steps. For example, the method of the invention may also combine all or part of the following steps:

- prior preparation of 1-decene via catalytic oligomerisation of ethylene;
- deactivation of the catalyst after oligomerisation of 1-decene or after catalytic hydrogenation of the oligomerisation products;
- recycling of the dimer fraction of 1-decene (e.g. 9-methyl-nonadecane), separated by distillation at reduced pressure, and oligomerisation of this recycled fraction of 1-decene dimers with 1-decene in the presence of hydrogen (H₂), a metallocene catalyst and an activating compound, or in the presence of hydrogen (H₂), a metallocene catalyst, an activator compound and co-activator compound;
- a final hydrogenation step of the trimer fraction comprising more than 50 weight % of 1-decene trimer of formula (I) in the presence of hydrogen (H₂) and a catalyst selected from among a hydrogenation catalyst and a palladium-containing hydrogenation catalyst.

The prior preparation of 1-decene via catalytic oligomerisation of ethylene is known per se. It may prove to be particularly advantageous in combination with the other steps of the method of the invention. This prior preparation of 1-decene via catalytic oligomerisation of ethylene particularly allows the use of more abundant sources of the starting substrate.
In addition, and preferably, once oligomerisation of 1-decene is completed, the method of the invention may comprise deactivation of the catalyst.
Deactivation of the oligomerisation catalyst can be conducted after oligomerisation of 1-decene or after catalytic hydrogenation of the oligomerisation products. Preferably, deactivation of the oligomerisation catalyst is performed after oligomerisation of 1-decene and before catalytic hydrogenation of the oligomerisation products.
Advantageously, deactivation of the catalyst is obtained via action of air or water or using at least one alcohol or solution of deactivating agent. Preferably, deactivation of the catalyst is obtained using at least one alcohol e.g. isopropanol.
In particularly advantageous manner, the method of the invention may also comprise recycling of the dimer fraction of 1-decene which is separated via distillation at reduced pressure, followed by oligomerisation of this recycled dimer fraction of 1-decene with 1-decene. Preferably, this recycled fraction of 1-decene dimers comprises 9-methyl-nonadecane.
Oligomerisation of this recycled fraction of dimers of 1-decene can then be conducted in the presence of hydrogen (H₂), a metallocene catalyst and an activator compound, or else in the presence of hydrogen (H₂), a metallocene catalyst, an activator compound and a co-activator compound.
Oligomerisation of this recycled fraction of dimers of 1-decene can be performed in the oligomerisation reactor of 1-decene or else in one or more separate reactors.
Preferably, it is performed in the oligomerisation reactor of 1-decene and under the same conditions as this oligomerisation of 1-decene.
In particularly advantageous manner, the recycling followed by oligomerisation of this recycled fraction of 1-decene dimers with 1-decene allows an improvement in the global yield of the preparation method of the invention, and thereby the production of a larger quantity of oil of the invention comprising more than 50 weight % of 9-methyl-11-octyl-henicosane.
Also preferably, the method of the invention may comprise a final hydrogenation step of the trimer fraction comprising more than 50 weight % of 1-decene trimer of formula (I). This final hydrogenation is performed in the presence of hydrogen (H₂) and a hydrogenation catalyst.
Preferably, the hydrogenation catalyst is selected from among a palladium derivative, a derivative of supported palladium, a derivative of alumina-supported palladium (e.g. on gamma-alumina), a nickel derivative, a derivative of supported nickel, a derivative of kieselguhr-supported nickel, a platinum derivative, a derivative of supported platinum, a cobalt-molybdenum derivative, a derivative of supported cobalt-molybdenum. More preferably, the hydrogen catalyst contains palladium. One particularly preferred catalyst comprises alumina-supported palladium (e.g. on gamma-alumina).
The hydrogenation catalyst is advantageously identical to the hydrogenation catalyst used for hydrogenation following after oligomerisation of 1-decene.
Advantageously, for final hydrogenation the hydrogen pressure (H₂) ranges from 5 to 50 bar or from 10 to 40 bar, preferably from 15 to 25 bar.
Also advantageously, for final hydrogenation the hydrogenation time is between 2 and 600 min, preferably between 30 and 300 min.
Advantageously for final hydrogenation, the temperature ranges from 50 to 200° C. or from 60 to 150° C. Preferably the temperature ranges from 70 to 140° C. or from 80 to 120° C.
Preferably, the oil of the invention is prepared using a method wherein:

- oligomerisation of 1-decene is conducted over a time ranging from 2 to 300 min or from 5 to 180 min or from 30 to 140 min; or
- oligomerisation of 1-decene is performed in the presence of hydrogen (H₂) at partial pressure ranging from 0.1 to 20 bar or from 1 to 6 bar; or
- oligomerisation is performed in the presence of hydrogen (H₂) in a weight ratio of hydrogen/1-decene higher than 100 ppm or lower than 600 ppm, or between 100 and 600 ppm; or
- oligomerisation of 1-decene is conducted at a temperature ranging from 50 to 200° C. or from 70 to 160° C. or from 80 to 150° C. or from 90 to 140° C. or from 100 to 130° C., or
- the metallocene catalyst is a racemic compound of formula (II):

L(Q¹)(Q²)MR¹R² (II)

- where:
  - M is a transition metal selected from among titanium, zirconium, hafnium and vanadium, or it is zirconium;
  - Q¹and Q², substituted or unsubstituted, are independently a cyclic tetrahydroindenyl group, or Q¹et Q²are independently a cyclic tetrahydroindenyl group and are bonded to form a polycyclic structure;
  - L is a Q¹and Q²bridging C₁-C₂₀divalent alkyl group, or L is a group selected from among methylene (—CH₂—), ethylene (—CH₂—CH₂—), methylmethylene (—CH(CH₃)—), 1-methyl-ethylene (—CH(CH₃)—CH₂—), n-propylene (—CH₂—CH₂—CH₂—), 2-methylpropylene (—CH₂—CH(CH₃)—CH₂—), 3-methylpropylene (—CH₂—CH₂—CH(CH₃)—), n-butylene (—CH₂—CH₂—CH₂—CH₂—), 2-methylbutylene (—CH₂—CH(CH₃)—CH₂—CH₂—), 4-methylbutylene (—CH₂—CH₂—CH₂—CH(CH₃)—), pentylene and isomers thereof, hexylene and isomers thereof, heptylene and isomers thereof, octylene and isomers thereof, nonylene and isomers thereof, decylene and isomers thereof, undecylene and isomers thereof, dodecylene and isomers thereof;
  - R¹and R², substituted or non-substituted, are independently an atom or group selected from among hydrogen, halogens (such as Cl and I), alkyl (such as Me, Et, nPr, iPr), alkenyl, alkynyl, haloalkyl, haloalkenyl, haloalkynyl, silylalkyl, silylalkenyls, silylalkynyls, germylalkyl, germylalkenyl, germylalkynyl; or R¹and R²together with M form a metallocycle having 3 to 20 carbon atoms; or
    the metallocene catalyst is selected from among rac-ethylene bis(tetrahydroindenyl) zirconium dimethyl and rac-ethylene bis(tetrahydroindenyl)zirconium dichloride; or
- oligomerisation of 1-decene is performed in a solvent selected from among a straight-chain or branched hydrocarbon, cyclic or non-cyclic hydrocarbon, an aromatic alkylated compound and mixtures thereof, or in a solvent selected from among butanes, pentanes, hexanes, heptanes, octanes, cyclopentane, cyclohexane, methylcyclopentane, methylcyclohexane, methylcycloheptane, toluene, xylene and mixtures thereof; or
- the activator compound is selected from among an ionic activator and oligomeric compound comprising residues of formula —Al(R)—O— where R is independently a cyclic or straight-chain C₁-C₂₀alkyl group; or the activator compound is selected from among methylalumoxane, modified methylalumoxane, ethylalumoxane, isobutylalumoxane and mixtures thereof; or the activator compound is selected from among dimethylanilinium tetrakis(perfluorophenyl)borate (DMAB), triphenylcarbonium tetrakis(perfluorophenyl)borate, dimethylanilinium tetrakis(perfluorophenyl)aluminate and mixtures thereof; or
- the co-activator compound is a trialkylaluminium derivative or compound selected from among tri-ethyl aluminium (TEAL), tri-iso-butyl aluminium (TIBAL), tri-methyl aluminium (TMA), tri-n-octyl aluminium and methyl-methyl-ethyl aluminium (MMEAL); or
- deactivation of the catalyst is obtained by action of air or water or using at least one alcohol or a solution of deactivating agent; or
- the pressure of hydrogen (H₂) during catalytic hydrogenation of the oligomerisation products ranges from 5 to 50 bar or from 10 to 40 bar or from 15 to 25 bar; or
- the hydrogenation catalyst is selected from among a palladium derivative, a derivative of supported palladium, a derivative of alumina-supported palladium (e.g. on gamma-alumina), a nickel derivative, a derivative of supported nickel, a derivative of kieselguhr-supported nickel, a platinum derivative, a derivative of supported platinum, a derivative of cobalt-molybdenum, a derivative of supported cobalt-molybdenum; or
- the hydrogen (H₂) pressure for final hydrogenation of the majority fraction by weight of 1-decene trimer of formula (I) ranges from 5 to 50 bar or from 10 to 40 bar or from 15 to 25 bar; or
- the hydrogenation time for final hydrogenation is between 2 and 600 min or between 30 and 300 min; or
- final hydrogenation finale is conducted at a temperature ranging from 50 to 200° C. or from 60 to 150° C. or from 70 to 140° C. or from 80 to 120° C., or
- the hydrogenation catalyst, for final hydrogenation of the trimer fraction comprising more than 50 weight % of 1-decene trimer of formula (I), is selected from among a palladium derivative, a derivative of supported palladium, a derivative of alumina-supported palladium (e.g. on gamma-alumina), a nickel derivative a derivative of supported nickel, a derivative of kieselguhr-supported nickel, a platinum derivative, a derivative of supported platinum, a cobalt-molybdenum derivative, a derivative of supported cobalt-molybdenum.

More preferably, the oil of the invention is prepared using a method combining all these characteristics.
Further preferably, the oil of the invention is prepared using a method wherein:

- oligomerisation of 1-decene is conducted over a time ranging from 30 to 140 min;
- oligomerisation of 1-decene is performed in the presence of hydrogen (H₂) at partial pressure ranging from1 to 6 bar;
- oligomerisation of 1-decene is performed at a hydrogen/1-decene weight ratio of between100 and 600 ppm;
- oligomerisation of 1-decene is conducted at a temperature ranging from 100 to 130° C.,
- the metallocene catalyst is selected from among rac-ethylene bis(tetrahydroindenyl) zirconium dimethyl and rac-ethylene bis(tetrahydroindenyl)zirconium dichloride;
- oligomerisation of 1-decene is performed in a solvent selected from among butanes, pentanes, hexanes, heptanes, octanes, cyclopentane, cyclohexane, methylcyclopentane, methylcyclohexane, methylcycloheptane, toluene, xylene and mixtures thereof;
- the activator compound is selected from among an ionic activator selected from among dimethylanilinium tetrakis(perfluorophenyl)borate, triphenylcarbonium tetrakis(perfluorophenyl)borate, dimethylanilinium tetrakis(perfluorophenyl)aluminate and mixtures thereof;
- the co-activator compound is a compound selected from among tri-ethyl aluminium (TEAL), tri-iso-butyl aluminium (TIBAL), tri-methyl aluminium (TMA), tri-n-octyl aluminium and methyl-methyl-ethyl aluminium (MMEAL);
- deactivation of the catalyst is obtained using at least one alcohol;
- the pressure of hydrogen (H₂) for catalytic hydrogenation of the oligomerisation products ranges from 15 to 25 bar;
- the hydrogenation catalyst is a derivative of alumina-supported palladium (e.g. on gamma-alumina);
- the pressure of hydrogen (H₂) for final hydrogenation of the majority fraction by weight of 1-decene trimer of formula (I) ranges from 15 to 25 bar;
- the hydrogenation time for final hydrogenation is between 30 and 300 min;
- final hydrogenation is conducted at a temperature ranging from 80 to 120° C.,
- the hydrogenation catalyst, for final hydrogenation of the trimer fraction comprising more than 50 weight % of 1-decene trimer of formula (I), is a derivative of alumina-supported palladium (e.g. on gamma-alumina).

In particularly advantageous manner, the oil of the invention is prepared using a method also comprising:

- prior preparation of 1-decene via catalytic oligomerisation of ethylene;
- deactivation of the catalyst after oligomerisation of 1-decene and before catalytic hydrogenation of the oligomerisation products;
- recycling of the dimer fraction of 1-decene (e.g. 9-methyl-nonadecane), separated by distillation at reduced pressure, and oligomerisation of this recycled fraction of 1-decene dimers with 1-decene, in the presence of hydrogen (H₂), a metallocene, catalyst, an activator compound and co-activator compound;
- a final hydrogenation step of the trimer fraction comprising more than 50 weight % of 1-decene trimer of formula (I), in the presence of hydrogen (H₂) and a catalyst selected from among a hydrogenation catalyst and hydrogenation catalyst containing alumina-supported palladium (par e.g. on gamma-alumina).

The invention also concerns the use of an oil of the invention as base oil or as lubricating base oil. This use therefore concerns a low-viscosity oil comprising more than 50 weight % of 9-methyl-11-octyl-henicosane.
The invention also concerns the use of an oil of the invention to improve the Fuel Eco (FE) of a lubricant. It also concerns use thereof to reduce the fuel consumption of an engine or to reduce the fuel consumption of a vehicle engine.
These uses also concern an oil of the invention such as defined by its advantageous, particular or preferred characteristics and by the preparation method thereof.
The invention also concerns a lubricating composition comprising an oil of the invention. This lubricating composition therefore comprises a low viscosity oil comprising more than 50 weight % of 9-methyl-11-octyl-henicosane.
Advantageously, the composition of the invention comprises at least 10 weight % or at least 20 weight % of an oil of the invention. Also advantageously, the composition of the invention comprises at least 30, 40, 50 or 60 weight % of an oil of the invention.
Also advantageously, the composition of the invention comprises an oil of the invention and at least one other base oil. It may also comprise an oil of the invention and at least one additive, or else an oil of the invention and at least one other base oil and at least one additive.
The lubricating composition of the invention may comprise an oil of the invention such as defined by its advantageous, particular or preferred characteristics and by the preparation method thereof.
As other base oil combined with the oil of the invention, the composition of the invention may comprise an oil selected from among an oil of group III, an oil of group IV.
The lubricating composition of the invention is particularly advantageous for use as high-performance lubricant for lubrication in the areas concerned by engines, gears, brakes, hydraulic fluids, coolants and greases.
The invention also concerns the use of a lubricating composition of the invention to improve the Fuel Eco (FE) of a lubricant. It also concerns use thereof to reduce the consumption of engine fuel or to reduce the fuel consumption of a vehicle engine.
The different aspects of the invention are the subject of the following examples which are given for illustrative purposes.

EXAMPLES

An autoclave reactor is used equipped with an agitator and a system controlling temperature and the feeding of nitrogen, hydrogen and 1-decene.
1-decene (produced by TCI or Acros) is used at purity higher than 94%. It is purified on 3 Å and 13× molecular sieves (Sigma-Aldrich). Before use, the molecular sieves are previously dried at 200° C. for 16 hours.
The products are characterized by ¹H NMR and two-dimensional gas chromatography (GC×GC).
For NMR, the PAO samples are diluted in deuterated chloroform and the NMR spectra are performed at 300 K on Bruker 400 MHz spectrometers: ¹H, ¹³C, HMQC (heteronuclear multiple quantum coherence) and HMBC (heteronuclear multiple bond coherence).
Two-dimensional chromatography is implemented in continuous mode and using two columns, apolar and polar. The entirety of the effluent derived from the first column is separated in the second dimension. Separation of the compounds is governed by volatility on the first column and by specific interactions (of type π-π, dipolar interactions etc.) on the second dimension. As a function of their viscosity, the samples are generally diluted twice in heptane. Chromatographic conditions were optimised in order to be able to elute the PAOs preparing according to the invention. The samples were analysed under GC×GC with cryogenic modulation (liquid nitrogen), programming of the first oven from 45° C. (5 min) up to 320° C. (20 min) with a ramp of 3° C/min, programming of the secondary oven from 60° C. (5 min) up to 330° C. (20 min) with a ramp of 3° C/min, and columns used under the following operating conditions:

- 1^stdimension: HP1, 25 m, ID 0.32 mm, film thickness: 0.17 μm,
- 2^anddimension: BPX-50, 1.5 m, ID 0.1 mm, film thickness: 0.1 μm,
- injector: split 100: 1, injected volume: 0.1 μl;
- detector: FID, 320° C.;
- hot jet temperature: 320° C.;
- cold jet programming from 80 to 5%;
- modulation period: 4.8 s.

Example 1

An 8 L autoclave reactor was used. Before use, the autoclave reactor was dried at 130° C. under a stream of nitrogen for one hour then cooled to 110° C. It was then filled with 3 500 mL of 1-decene under a stream of nitrogen. The temperature of the reactor was held at 110° C. and hydrogen (H₂) was fed at a m/m ratio of H₂/1-decene of 414 ppm.
The catalyst was rac-ethylene bis(tetrahydroindenyl) zirconium dimethyl activated with dimethylanilinium tetrakis(perfluorophenyl)borate (DMAB) in a B/Zr molar ratio of 1.75. Triisobutyl aluminium (TiBAI) was used as co-activator compound with Al/Zr molar ratio of 200. It allows trapping of impurities contained in the reactor.
Oligomerisation started to occur as soon as the activated catalyst was added in a concentration of 17 μM relative to the oligomerisation solution.
After 120 min, 5 mL of isopropanol were added to deactivate the catalyst. Hydrogenation of the reaction products was then carried out using an alumina-supported palladium catalyst (5 g of palladium on gamma-alumina at 5% m/m relative to the alumina product by Alfa Aesar) and hydrogen (H₂) at 20 bar, at a temperature of 100° C., for 240 min.
The oligomerisation products and the trimer fraction comprising more than 50 weight % of 9-methyl-11-octyl-henicosane were then separated by distillation at reduced pressure (0.67 mBar or 0.5 mmHg) in two steps first in accordance with standard ASTM D2892 and then with standard ASTM D5236 (1) using a column with 15 theoretical plates and maximum temperature of 375° C., then (2) using a column with 2 theoretical plates and vapour temperature at the head of the column ranging from 375 to 445° C.
Distillation following standard ASTM D2892 allows the separation of products having a boiling point lower than 375° C. Distillation following standard ASTM D5236 allows isolation of the products having a boiling point ranging from 375 to 445° C. The content of 9-methyl-11-octyl-henicosane in the oil of the invention is 71.4%.
This oil of the invention comprising more than 50 weight % of 9-methyl-11-octyl-henicosane has kinematic viscosity at 100° C., measured according to standard ASTM D445, of 3.448 mm².s⁻¹. The viscosity index of this oil is 130. Its volatility, measured according to standard ASTM D6375 is 10.3% by mass and its cold cranking viscosity (CCS) at −35° C., measured according to standard ASTM D5293, is 780 mPa·s. Its mean molecular mass is 372 g/mol.
The characteristics of the oil of the invention allow excellent lubricating, rheological and oxidation resistance properties to be obtained as well as Fuel Eco.

Example 2

Procedure was the same as for Example 1 for oligomerisation of 1-decene.
The oligomerisation products and trimer fraction comprising more than 50 weight % of 9-methyl-11-octyl-henicosane were then separated by distillation at reduced pressure (0.67 mBar or 0.5 mmHg) in two steps, first according to standard ASTM D2892 and then according to standard ASTM D5236 : (1) using a column with 15 theoretical plates and maximum temperature of 375° C., then (2) using a column with 2 theoretical plates and vapour temperature at the head of the column ranging from 445 to 465° C.
Distillation according to standard ASTM D2892 allows the separation of products having a boiling point lower than 375° C. Distillation according to standard ASTM D5236 allows isolation of the products having a boiling point ranging from 445 to 465° C.
The oil of the invention obtained has a 9-methyl-11-octyl-henicosane content of 65.7%.
This oil of the invention comprising more than 50 weight % of 9-methyl-11-octyl-henicosane has kinematic viscosity at 100° C., measured according to standard ASTM D445, of 3.640 mm².s^-1. The viscosity index of this oil is 132. Its volatility measured according to standard ASTM D6375 is 9.1% by mass and its cold cranking viscosity (CCS) at -35° C., measured according to standard ASTM D5293, is 890 mPa·s. Its mean molecular mass is 383 g/mol.
Again, the characteristics of this oil of the invention allow excellent lubricating, rheological and oxidation resistance properties to be obtained, as well as Fuel Eco.

Example 3

Procedure was the same as for Example 1 to prepare a first oil fraction of the invention. Procedure was the same as in Example 2 to prepare a second oil fraction of the invention. The two fractions were then assembled together.
Final hydrogenation was then carried out using a palladium catalyst (0.5% m/m relative to H₂) supported on alumina (5 g of palladium on gamma-alumina at 5% m/m relative to the alumina product by Alfa Aesar) and hydrogen (H₂) at 20 bar, at a temperature of 90° C., for 240 min.
The oil of the invention obtained has a 9-methyl-11-octyl-henicosane content of 74.7%.
This oil of the invention comprising more than 50 weight % of 9-methyl-11-octyl-henicosane has kinematic viscosity at 100° C., measured according to standard ASTM D445, of 3.569 mm².s⁻¹. The viscosity index of this oil is 130. Its volatility measured according to standard ASTM D6375 is 10.3% by mass and its cold cranking viscosity (CCS) at −35° C., measured according to standard ASTM D5293, is 720 mPa·s. Its mean molecular mass is 378 g/mol.
Again, the characteristics of the oil of the invention allow excellent lubricating, rheological and oxidation resistance properties to be obtained, as well as Fuel Eco.

Comparative Example 1

Identical measurements and characterizations were carried out using a reference commercial oil. This was a PAO oil (produced by ExxonMobil Spectrasyn Plus 3.6) prepared from olefins via acid catalysis.
This reference PAO oil has kinematic viscosity at 100° C., measured according to standard ASTM D445, of 3.671 mm².s⁻¹. It has a viscosity index is 118. Its volatility measured according to standard ASTM D6375 is 14.3% by mass and its cold cranking viscosity (CCS) at −35° C., measured according to standard ASTM D5293 is 1100 mPa·s. Its mean molecular mass is 374 g/mol.
Also, the specifications of this commercial oil are the following: kinematic viscosity at 100° C., measured according to standard ASTM D445, of 3.5 to 3.9 mm².s⁻¹; volatility measured according to standard ASTM D5800 lower than 17% by mass.
The method of the invention therefore allows the preparation of an oil having properties that are equivalent to or better than those of commercial PAO oils, in particular the viscosity index or cold cranking viscosity of the oils of the invention have much higher ratings.

Claims

1-18 (canceled)

19. Oil having kinematic viscosity at 100° C., measured according to standard ASTM D445, ranging from 3 to 4 mm².s⁻¹, comprising more than 50 weight % of 1-decene trimer of formula (I)

20. The oil according to claim 19 comprising 50 to 99 weight % of 1-decene trimer of formula (I), or 60 to 90 weight % of 1-decene trimer of formula (I), or 70 to 90 weight % of 1-decene trimer of formula (I).

21. The oil according to claim 19 comprising at least 65 weight % of 1-decene trimer of formula (I), or at least 70 weight % of 1-decene trimer of formula (I) , or at least 80 weight % of 1-decene trimer of formula (I), or at least 90 weight % of 1-decene trimer of formula (I).

22. The oil according to claim 19 also comprising at least one other saturated oligomer of 1-decene:

selected from among the other trimers of 1-decene; or

selected from among the dimers of 1-decene, the other trimers of 1-decene, the tetramers of 1-decene, the pentamers of 1-decene.

23. The oil according to claim 19 also comprising at least one other saturated oligomer of 1-decene selected from among 9-methyl-nonadecane and 9-methyl-11,13-dioctyl-tricosane.

24. The oil according to claim 19 comprising 51 to 99.9 weight % of 1-decene trimer of formula (I) and 0.1 to 49 weight % of at least one other saturated trimer of 1-decene.

25. The oil according to claim 19 comprising:

51 to 99.6 weight % of 1-decene trimer of formula (I);

0.1 to 1 weight % of at least one saturated dimer of 1-decene or of 9-methyl-nonadecane;

0.1 to 25 weight % of at least one other saturated trimer of 1-decene;

0.1 to 20 weight % of at least one saturated tetramer of 1-decene or of 9-methyl-11,13-dioctyl-tricosane;

0.1 to 1.5 weight % of at least one saturated pentamer of 1-decene.

26. The oil according to claim 19 wherein:

(a) the kinematic viscosity at 100° C., measured according to standard ASTM D445, ranges from 3.2 to 3.8 mm².s⁻¹or is 3,5 mm².s⁻¹; or wherein

(b) the viscosity index is higher than 120, or is 130 or higher, or is between 120 and 140 or between 125 and 135; or wherein

(c) the volatility measured according to standard ASTM D6375 is lower than 10.8% by mass or lower than 10.5% by mass; or wherein

(d) the cold cranking viscosity (CCS) at −35° C., measured according to standard ASTM D5293, is lower than 900 mPa·s or lower than 800 mPa·s.

27. The oil according to claim 19 wherein:

(a) the kinematic viscosity at 100° C., measured according to standard ASTM D445, ranges from 3.2 to 3.8 mm².s⁻¹or is 3,5 mm².s⁻¹; and wherein

(b) the viscosity index is higher than 120, or is 130 or higher, or is between 120 and 140 or between 125 and 135; and wherein

(c) the volatility measured according to standard ASTM D6375 is lower than 10.8% by mass or lower than 10.5% by mass; and wherein

28. The oil according to claim 19 comprising 1-decene trimer of formula (I), prepared using a method comprising:

oligomerisation of 1-decene in the presence of hydrogen (H₂), a metallocene catalyst and an activator compound, or in the presence of hydrogen (H₂), a metallocene catalyst, an activator compound and a co-activator compound;

catalytic hydrogenation of the oligomerisation products in the presence of hydrogen (H₂) and a catalyst selected from among a hydrogenation catalyst and a palladium-containing hydrogenation catalyst;

separation via distillation at reduced pressure of the trimer fraction comprising more than 50 weight % of 1-decene trimer of formula (I).

29. The oil according to claim 19 comprising 1-decene trimer of formula (I), prepared using a method comprising

separation via distillation at reduced pressure of the trimer fraction comprising more than 50 weight % of 1-decene trimer of formula (I);

also comprising:

prior preparation of 1-decene via catalytic oligomerisation of ethylene; or

deactivation of the catalyst after oligomerisation of 1-decene or after catalytic hydrogenation of the oligomerisation products;

recycling of the dimer fraction of 1-decene (e.g. 9-methyl-nonadecane), separated by distillation at reduced pressure, and oligomerisation of this recycled dimer fraction of 1-decene with 1-decene, in the presence of hydrogen (H₂), a metallocene catalyst and an activator compound, or in the presence of hydrogen (H₂), a metallocene catalyst, an activator compound and a co-activator compound; or

a final hydrogenation step of the trimer fraction comprising more than 50 weight % of 1-decene trimer of formula (I) in the presence of hydrogen (H₂) and a catalyst selected from among a hydrogenation catalyst and palladium-containing hydrogenation catalyst.

30. The oil according to claim 19 comprising 1-decene trimer of formula (I) prepared using a method comprising:

wherein:

oligomerisation of 1-decene is conducted over a time ranging from 2 to 300 min or from 5 to 180 min or from 30 to 140 min; or

oligomerisation of 1-decene is conducted in the presence of hydrogen (H₂) at partial pressure ranging from 0.1 to 20 bar or from 1 to 6 bar; or

oligomerisation is performed with a hydrogen/1-decene weight ratio higher than 100 ppm or lower than 600 ppm or between 100 and 600 ppm; or

oligomerisation of 1-decene is conducted at a temperature ranging from 50 to 200° C. or from 70 to 160° C. or from 80 to 150° C. or from 90 to 140° C. or from 100 to 130° C.; or

the metallocene catalyst is a racemic compound of formula (II)

L (Q¹) (Q²) MR¹R² (II)

where:

M is a transition metal selected from among titanium, zirconium, hafnium and vanadium, or it is zirconium;

Q¹and Q², substituted or unsubstituted, are independently a cyclic tetrahydroindenyl group or Q¹and Q²are independently a cyclic tetrahydroindenyl group and are bonded to form a polycyclic structure;

L is a Q¹and Q²bridging C₁-C₂₀divalent alkyl group or L is a group selected from among methylene (—CH₂—), ethylene (—CH₂—CH₂—), methylmethylene (—CH(CH₃)—), 1-methyl-ethylene (—CH(CH₃)—CH₂—), n-propylene (—CH₂—CH₂—CH₂—), 2-methylpropylene (—CH₂—CH(CH₃)—CH₂—), 3-methylpropylene (—CH₂—CH₂—CH(CH₃)—), n-butylene —CH₂—CH₂—CH₂—CH₂—), 2-methylbutylene (—CH₂—CH(CH₃)—CH₂—CH₂—), 4-methylbutylene (—CH₂—CH₂—CH₂—CH(CH₃)—), pentylene and isomers thereof, hexylene and isomers thereof, heptylene and isomers thereof, octylene and isomers thereof, nonylene and isomers thereof, decylene and isomers thereof, undecylene and isomers thereof, dodecylene and isomers thereof;

R¹and R², substituted or unsubstituted are independently an atom or a group selected among hydrogen, halogens (such as Cl and I), alkyl (such as Me, Et, nPr, iPr), alkenyl, alkynyl, haloalkyl, haloalkenyl, haloalkynyl, silylalkyl, silylalkenyls, silylalkynyls, germylalkyl, germylalkenyl, germylalkynyl; or R¹et R²together with M form a metallocycle having 3 to 20 carbon atoms; or

the metallocene catalyst is selected from among rac-ethylene bis(tetrahydroindenyl) zirconium dimethyl and rac-ethylene bis(tetrahydroindenyl)zirconium dichloride; or

oligomerisation of 1-decene is performed in a solvent selected from among a straight-chain or branched hydrocarbon, cyclic or noncyclic hydrocarbon, an aromatic alkylated compound and mixtures thereof, or in a solvent selected from among butanes, pentanes, hexanes, heptanes, octanes, cyclopentane, cyclohexane, methylcyclopentane, methylcyclohexane, methylcycloheptane, toluene, xylene and mixtures thereof; or

the activator compound is selected from among an ionic activator and an oligomeric compound comprising residues of formula —Al(R)—O— where R is independently a cyclic or straight-chain C₁-C₂₀alkyl group; or the activator compound is selected from among methylalumoxane, methylalumoxane modify, ethylalumoxane, isobutylalumoxane and mixtures thereof; or the activator compound is selected from among dimethylanilinium tetrakis(perfluorophenyl)borate (DMAB), triphenylcarbonium tetrakis(perfluorophenyl)borate, dimethylanilinium tetrakis(perfluorophenyl)aluminate and mixtures thereof; or

the co-activator compound is a trialkylaluminium derivative or a compound selected from among tri-ethyl aluminium (TEAL), tri-iso-butyl aluminium (TIBAL), tri-methyl aluminium (TMA), tri-n-octyl aluminium and methyl-methyl-ethyl aluminium (MMEAL); or

deactivation of the catalyst is obtained via action of air or water or using at least one alcohol or solution of deactivating agent; or

the pressure of hydrogen (H₂) for catalytic hydrogenation of the oligomerisation products ranges from 5 to 50 bar or from 10 to 40 bar or from 15 to 25 bar; or

the hydrogenation catalyst is selected from among a palladium derivative, supported palladium derivative, a derivative of alumina-supported palladium (e.g. on gamma-alumina), a nickel derivative, a derivative of supported nickel, a derivative of kieselguhr-supported nickel, a platinum derivative, derivative of supported platinum, cobalt-molybdenum derivative, derivative of supported cobalt-molybdenum; or

the pressure of hydrogen (H₂) for final hydrogenation of the majority fraction by weight of 1-decene trimer of formula (I) ranges from 5 to 50 bar or from 10 to 40 bar or from 15 to 25 bar; or

the hydrogenation time for final hydrogenation is between 2 and 600 min or between 30 and 300 min; or

final hydrogenation finale is conducted at a temperature ranging from 50 to 200° C. or from 60 to 150° C. or from 70 to 140° C. or from 80 to 120° C.; or

the hydrogenation catalyst, for final hydrogenation of the trimer fraction comprising more than 50 weight % of 1-decene trimer of formula (I), is selected from among a palladium derivative, derivative of supported palladium, derivative of alumina-supported palladium (e.g. on gamma-alumina), a nickel derivative, a derivative of supported nickel, a derivative of kieselguhr-supported nickel, a platinum derivative, supported platinum derivative, cobalt-molybdenum derivative, supported cobalt-molybdenum derivative.

31. The oil according to claim 19 comprising 1-decene trimer of formula (I) prepared using a method comprising:

wherein:

oligomerisation of 1-decene is conducted over a time ranging from 2 to 300 min, or from 5 to 180 min or from 30 to 140 min;

oligomerisation of 1-decene is performed in the presence of hydrogen (H₂) at partial pressure ranging from 0.1 to 20 bar or from 1 to 6 bar;

oligomerisation of 1-decene is performed with a hydrogen/1-decene weight ratio higher than 100 ppm or lower than 600 ppm or between 100 and 600 ppm; or

oligomerisation of 1-decene is conducted at a temperature ranging from 50 to 200° C., or from 70 to 160° C., or from 80 to 150° C., or from 90 to 140° C. or from 100 to 130° C.;

the metallocene catalyst is a racemic compound of formula (II).

L(Q¹) (Q²)MR¹R² (II)

where:

Q¹and Q², substituted or unsubstituted are independently a cyclic tetrahydroindenyl group or Q¹and Q²are independently a cyclic tetrahydroindenyl group and are bonded to form a polycyclic structure;

L is a Q¹and Q²bridging C₁-C₂₀divalent alkyl group, or L is a group selected from among methylene (—CH₂—), ethylene (—CH₂CH₂—), methylmethylene (—CH(CH₃)—), 1-methyl-ethylene (—CH(CH₃)—CH₂—), n-propylene (—CH₂—CH₂—CH₂—), 2-methylpropylene (—CH₂—CH(CH₃)—CH₂—), 3-methylpropylene (—CH₂—CH₂—CH(CH₃)—), n-butylene (—CH₂—CH₂—CH₂—CH₂—), 2-methylbutylene (—CH₂—CH(CH₃)—CH₂—CH₂—), 4-methylbutylene (—CH₂—CH₂—CH₂—CH(CH₃)—), pentylene and isomers thereof, hexylene and isomers thereof, heptylene and isomers thereof, octylene and isomers thereof, nonylene and isomers thereof, decylene and isomers thereof, undecylene and isomers thereof, dodecylene and isomers thereof;

R¹and R², substituted or unsubstituted are independently an atom or group selected from among hydrogen, halogens (such as Cl and I), alkyl (such as Me, Et, nPr, iPr), alkenyl, alkynyl, haloalkyl, haloalkenyl, haloalkynyl, silylalkyl, silylalkenyls, silylalkynyls, germylalkyl, germylalkenyl, germylalkynyl; or R¹and R²together with M form a metallocycle having 3 to 20 carbon atoms; or

the metallocene catalyst is selected from among rac-ethylene bis(tetrahydroindenyl) zirconium dimethyl and rac-ethylene bis(tetrahydroindenyl)zirconium dichloride;

oligomerisation of 1-decene is performed in a solvent selected from among a straight-chain or branched hydrocarbon, cyclic or non-cyclic hydrocarbon, an aromatic alkylated compound and mixtures thereof, or in a solvent selected from among butanes, pentanes, hexanes, heptanes, octanes, cyclopentane, cyclohexane, methylcyclopentane, methylcyclohexane, methylcycloheptane, toluene, xylene and mixtures thereof;

the activator compound is selected from among an ionic activator and oligomeric compound comprising residues of formula —Al(R)—O— where R is independently a cyclic or straight-chain C₁-C₂₀alkyl group; or the activator compound is selected from among methylalumoxane, modified methylalumoxane, ethylalumoxane, isobutylalumoxane and mixtures thereof; or the activator compound is selected from among dimethylanilinium tetrakis(perfluorophenyl)borate, triphenylcarbonium tetrakis(perfluorophenyl)borate, dimethylanilinium tetrakis(perfluorophenyl)aluminate and mixtures thereof;

the co-activator compound is a trialkylaluminium derivative or a compound selected from among tri-ethyl aluminium (TEAL), tri-iso-butyl aluminium (TIBAL), tri-methyl aluminium (TMA), tri-n-octyl aluminium and methyl-methyl-ethyl aluminium (MMEAL);

deactivation of the catalyst is obtained via action of air or water or using at least one alcohol or a solution of deactivating agent; or

the pressure of hydrogen (H₂) for catalytic hydrogenation of the oligomerisation products ranges from 5 to 50 bar, or from 10 to 40 bar or from 15 to 25 bar;

the hydrogenation catalyst is selected from among a palladium derivative, derivative of supported palladium, derivative of alumina-supported palladium (e.g. on gamma-alumina), a nickel derivative, derivative of supported nickel, derivative of kieselguhr-supported nickel, a platinum derivative, derivative of supported platinum, cobalt-molybdenum derivative, supported cobalt-molybdenum derivative;

the pressure of hydrogen (H₂) for final hydrogenation of the majority fraction by weight of 1-decene trimer of formula (I) ranges from 5 to 50 bar, or from 10 to 40 bar or from 15 to 25 bar;

the hydrogenation time for final hydrogenation is between 2 and 600 min or between 30 and 300 min;

final hydrogenation is conducted at a temperature ranging from 50 to 200° C., or from 60 a 150° C., or from 70 to 140° C. or from 80 to 120° C.;

the hydrogenation catalyst, for final hydrogenation of the trimer fraction comprising more than 50 weight % of 1-decene trimer of formula (I), is selected from among a palladium derivative, a derivative of supported palladium, derivative of alumina-supported palladium (e.g. on gamma-alumina), a nickel derivative, supported nickel derivative, kieselguhr-supported nickel derivative, a platinum derivative, supported platinum derivative, cobalt-molybdenum derivative, supported cobalt-molybdenum derivative.

32. A base oil comprising the oil according to claim 19.

33. A method to improve the Fuel Eco (FE) of a lubricant, or to reduce the fuel consumption of an engine or to reduce the fuel consumption of a vehicle engine, comprising applying an effective amount of the oil of claim 19.

34. A lubricating composition comprising:

at least one base oil selected from among an oil according to claim 19; or

at least one base oil selected from among an oil according to claim 19 and at least one other base oil; or

at least one base oil selected from among an oil according to claim 19 and at least one additive; or

at least one base oil selected from among an oil according to claim 19, at least one other base oil and at least one additive.

35. The lubricating composition according to claim 34 comprising at least 10 weight % of the at least one base oil.

36. A method to improve the Fuel Eco (FE) of a lubricant, or to reduce the fuel consumption of an engine or to reduce the fuel consumption of a vehicle engine, comprising applying an effective amount of the lubricating composition according to claim 34.

37. The lubricating composition according to claim 34 comprising at least 20 weight % of the at least one base oil.

38. The lubricating composition according to claim 34 comprising at least 30 weight % of the at least one base oil.