FR2484440A1 - PROCESS FOR PRODUCING AN OXIDATION-RESISTANT OIL COMPOSITION AND COMPOSITION OBTAINED THEREBY - Google Patents

Abstract

THE INVENTION RELATES TO A PROCESS FOR THE PRODUCTION OF AN OXIDIZATION RESISTANT OIL COMPOSITION. THE PROCESS CONSISTS OF FORMING A MIXTURE COMPRISING 85 TO 99.9 BY WEIGHT OF A HYDROCARBON ALKYLATION OIL AND 15 TO 0.1 BY WEIGHT OF A REFINED FRACTION HAVING A SULFUR CONTENT OF AT LEAST 1.0 BY WEIGHT OBTAINED BY CATALYTIC HYDROGEN REFINING OF A HYDROCARBON FRACTION HAVING AN ANILINE POINT NOT EXCEEDING 60 C AND CONTAINING AT LEAST 2.0 BY WEIGHT OF SULFUR, THE CONDITIONS FOR CATALYTIC HYDROGEN REFINING INVOLVING A TEMPERATURE OF 220 TO 300 C AND A PARTIAL HYDROGEN PRESSURE OF 2 TO 5MPA. IN ONE EMBODIMENT, HYDROCARBON ALKYLATION OIL IS AN ALKYLATION PRODUCT OF BENZENE WITH A TETRAMER OF PROPYLENE AND THE HYDROCARBON FRACTION IS A FRACTION OBTAINED BY THERMAL OR CATALYTIC CRACKING. APPLICATION AS OIL FOR ELECTRICAL USE OR OIL FOR TURBINE.

Description

The present invention relates to a method for producing a composition

oil resistant to oxidation,

and a composition thus produced.

  Oil-based compositions are usually required to be stable, especially to oxidation, and especially if the intended application extends for a relatively long period of time before they are replaced and / or or thrown. The oxidation stability of oil-based compositions is all the more important and difficult to achieve that the usual conditions of use tend to favor degradation.

by oxidation.

  The present invention provides a process for

  producing an oil composition of high oxidation resistance, comprising the steps of:

  (a) subjecting a hydrocarbon fraction

  within the temperature range of the

  end position and having an aniline point not exceeding 600C and a sulfur content of at least 2.0% by weight, at a

  catalytic refining treatment with hydro-

  at a temperature in the range of 220 to 300 ° C and at a hydrogen partial pressure in the range of 2 to 5 MPa to produce a refined fraction having a sulfur content of at least 1.0% by weight. weight; and (b) forming a mixture comprising 85 to 99.9% by weight of a hydrocarbon oil formed by

  alkylation and boiling in the tempera-

  temperatures of the desired final composition and

  0.1% by weight of said refined fraction.

  Preferably, the hydrocarbon oil formed by alkylation and said refined fraction boil in the

  boiling range of a lubricating oil.

  The mixture obtained by the process of the invention

  can be used, for example, as an oil for electrical

as and as turbine oil.

  An important advantage of the process of the invention is that the physical properties of the resulting oil compositions are largely determined by the nature of the alkylating hydrocarbon oil, and within certain limits it is possible to synthesize hydrofluorocarbon oils.

  carbonates of alkylation so that they have

  physical properties such as, for example, viscosity, pour point and flash point, which are

  in a predetermined desired range.

  Preferably, the hydrogen partial pressure in step (a) is in the range of 3 to 4 MPa and the temperature in step (a) is preferably in the range of

range from 240 to 2800C.

  Said hydrocarbon fraction preferably has an aniline point not exceeding 350C and preferably a density (at 15 ° C) of at least 0, 900, preferably at least 1.00, before the step of catalytic refining with hydrogen, and preferably the refined fraction produced in the step

  (a) has a sulfur content of at least 2.0% by weight.

  The hydrocarbon fraction may have a content

  in sulfur by at least 3.5% by weight before the refining stage.

catalytic fining with hydrogen.

  Step (a) can be conducted at a liquid hourly space velocity (h 1) of 0.3 to 2.0, preferably

from 0.5 to 1.0.

  The catalytic hydrogen refining of the stage

  (a) is preferably carried out in the presence of a catalyst

  including a component of a Group VI metal and a

  component of a Group VIII non-noble metal on a support.

  Suitable catalysts may contain carbon and molybdenum; nickel and molybdenum; or nickel and tungsten. Catalysts are particularly preferred

  containing nickel and tungsten.

  The hydrocarbon fraction may be a hydrocarbon fraction rich in aromatics obtained by cracking

  thermal or catalytic loading of heavy hydrocarbons.

  Naturally, thermal cracking includes cracking to

steam.

  The hydrocarbon oil in question is preferably

  It is formed by alkylating an aromatic hydrocarbon with an olefinic polymer, the latter being preferably a propylene polymer. A suitable olefinic polymer comprises dodecene obtained by polymerization of propylene in the presence of a catalyst containing BF 3 and H 2 O or

phosphoric acid.

  The aromatic hydrocarbon is advantageously

  formed entirely or mainly of benzene.

  The alkylation may be catalyzed by a catalyst comprising AlCl 3 or any other well known alkylation catalyst.

  The present invention also proposes a

  oil position of high resistance to oxidation, obtained

  by a method as defined above.

  Other details of the present invention

  By way of nonlimiting example, hereinafter: A synthetic hydrocarbon base oil having physical characteristics favorable for its use as a dielectric oil in a transformer is prepared as follows

  Propylene is passed through contact with

  commercial polymerization system comprising BF3 and water and the polymeric products are collected

  olefinic polymer fraction at C12.

  The collected polymeric fraction is used

  for alkylating benzene in the presence of an alkylation catalyst

  comprising AlCl3. The resulting alkylation product,

  after purification, contains, according to the chroma-

  gas phase graphography, 96% by weight of C12 alkyl benzene and 4% by weight of alkylbenzenes with

C9-C15 alkyl radicals.

  The alkylation product has the following characteristics: Viscosity (m2 / s) at -30VC 5.05

00C 0.316

VC 0.115

98.9-C 0.017

  Flashpoint, open vase Cleveland ,. C 133 Pour point Oc -60 Bromine number 0.25 The above characteristics suggest that the alkylation product must be suitable for use as a transformer oil. A recognized aptitude test for transformer oils is the well-known Baader test. The alkylation product was subjected to the Baader test and the Baader saponification number found was 4.2 mg KOH / g, which is well above the maximum limit of 0.6. mg of KOH / g fixed by the "Verbindung Deutsche Elektrotechnische" and adopted as DIN 0370

  in the Federal Republic of Germany.

  Mixtures of the alkylation product have been formed with different sulfur-rich fractions containing

  aromatic hydrocarbons which have been subjected to

  catalytic refining with hydrogen under conditions

  relatively mild treatment conditions.

  One of these fractions, namely the fraction A, is a fraction boiling approximately in the same

  the product of alkylation and obtained by an

  catalytic cracking. Another similar fraction, called fraction B, results from the distillation of a tar

  produced during steam cracking.

  Fractions A and B were refined with hydro-

  under mild conditions in the presence of a supported nickel and molybdenum catalyst in

  the hydrogen refining conditions set out above

  after WHSV (h-1 0.7 Partial hydrogen pressure (MPa) 3.0 Volume ratio H2 / fraction 100 Temperature 240 The properties of fractions A and B before and after

  catalytic refining with hydrogen were the following

your

A B

  Before After Before After refining refining refining refining

Refractive index -

at 600C 1,587 1,572 1,631 1,615

  Density at 15 ° C 1,007 0,989 1,060 1,051 Aniline point (OC) 33 32 14 9 Viscosity at 400C, m2 / s 0.156 0.133 0.087 0.074 Sulfur content (% by weight) 3.5 2.4 5.0 4, Nitrogen content (ppm) A mixture of 95% by weight of the alkylation product and 5% by weight of each of the hydrogenated fractions A and B is formed. We study for each mixture *

  oxidation stability by the Baader test; the results

  The following are reproduced below: Mixture Baader saponification number (mg KOH / g)% by weight of alkylation product + 5% of refined fraction A 0.06% by weight of alkylation product + 5% fraction B refined 0.03 It follows from the above that the mixture of

  alkylation product and a small proportion of the

  hydrogen-rich, sulfur-rich and aromatic-rich, dramatically reduces the Baader saponification index compared to that of the pure alkylation product, at a value well below the maximum

  specified in DIN 0370. Such mixtures are suitable

  well for applications where stability

  to oxidation is an important factor.

  Similar advantages are obtained using the present invention when the alkylation product is

for example a polyalphaolefin.

Claims (11)

  A process for producing an oil composition of high resistance to oxidation, characterized in that it comprises the steps of: (a) subjecting: a hydrocarbon-based hydrocarbon fraction;   within the temperature range of the   end position and having an aniline point not exceeding 600C and a sulfur content of at least 2.0% by weight, at a   catalytic refining treatment with hydro-   a gene at a temperature in the range of 220 to 3000C and a hydrogen partial pressure in the range of 2 to 5 MPa to produce a refined fraction having a sulfur content of at least 1.0% by weight; and (b) forming a mixture comprising 85 to 99.9% by weight of a hydrocarbon oil formed by   alkylation and boiling in the tempera-   temperatures of the desired final composition and   0.1% by weight of said refined fraction.   2. Process according to claim 1, characterized in that the hydrogen partial pressure in step (a)   is in the range of 3 to 4 MPa ..   3. Method according to one of claims 1 and   2, characterized in that the temperature in step (a) is   lies in the range of 240 to 2800C.   4. A process according to any of the claims   cations i to 3, characterized in that the hydrocarbon fraction   born at an aniline point not exceeding 350C before the   catalytic refining with hydrogen.   5. A process according to any of the claims   1 to 4, characterized in that the refined fraction produced in step (a) has a sulfur content of at least 2.0% by weight.   6. A method according to any of the claims   1 to 5, characterized in that the hydrocarbon fraction   has a sulfur content of at least 3.5% by weight.   7. Process according to any one of the   1 to 6, characterized in that step (a) is carried out at a liquid hourly space velocity (h 1) from 0.3 to 2.0.   8. Process according to any one of the   1 to 7, characterized in that the catalytic refining   The hydrogen phase in step (a) is carried out in the presence of a catalyst comprising a Group VI metal component and a Group non-noble metal component. VIII.   9. A process according to any of the claims   1 to 8, characterized in that the hydrocarbon fraction   is a hydrocarbon fraction rich in aromatics obtained by thermal or catalytic cracking of a filler formed of heavy hydrocarbons.   10. Process according to any one of the   1 to 9, characterized in that the hydrocarbon oil has been obtained by alkylation of an aromatic hydrocarbon with an olefinic polymer.   11. A composition of oil of great resistance   to oxidation, obtained by a process according to any one conque of claims 1 to 10.