CS252868B1 - The method of producing raffinates from petroleum oil fractions! - Google Patents

Abstract

A method of refining petroleum oil fractions by combining hydrogenation transformation steps of the structural-type composition of the oil fraction and subsequent hydroextractive refining with a selective solvent, with the aim of increasing yields and improving the quality of raffinates for the production of oils, especially automotive, turbine and electrical insulation oils. It is applicable in oil processing plants that produce base oils as well as other lubricating oils.

Description

SUMMARY OF THE INVENTION The present invention relates to the improvement of efficiency and yields in the production of raffinates from petroleum oil fractions by coimbimizing the postuipes of the hydrogelation conversion of the stratum-type oil composition and the subsequent liquid extractive refinery with the efficacy.

Current methods of refining petroleum oil fractions 1, in order to enhance their performance, generally include the technological processes of liquid extraction, evaporation and hydrogenation purification. The hydrotreatment process has been developed and applied in practice as a substitute for acid and adsorption doraffination, which, however, can also be included in the refining sequence in the spherical refining process.

The raffinates which are semi-trailers for the production of oils, especially automotive, turbine, electrical insulating materials, must meet some specific quality criteria.

Of these criteria, a special stop is mainly due to the low content of bi- and polycyclic aromatic hydrocarbons and the bile-containing sulfur, nitrogen and oxygen bonded in the molecule.

The directness of the said substances affects the negative most of the desired properties of the semi-finished product, such as the viscosity-temperature curve expressed by viscosity index, oxidation stability and dielectric properties.

The bi- and polycyclic aromatic hydrocarbons and the sulfur, nitrogen and oxygen compounds bound in these molecules have a very high viscosity dependence on iteplote, i.e. have a low viscosity index. During oxidation, especially at higher temperatures, they are allowed to form pitches, oil-insoluble deposits, and significantly deteriorate the dielectric properties of the electrical insulating oils.

It is common practice to remove these types of substances by extraction using selective solvents, wherein the named bi- and polycyclic, optionally sulfur, nitrogen, oxygen-containing molecules pass into the solvent phase as an extract. A raffinate phase, substantially devoid of these molecules, is obtained which has markedly improved indicators of viscosity index, oxidation stability and other utility or processing properties.

The disadvantage of this procedure, in the case of oil-based fragrances, is subjected to selective solvent-based extraction refining, is that, from some types of crude oil, characterized by a higher or high content of bi- and poly-cyclic aromatic aromas, they are obtained during extraction. unsatisfactory raffinate extracts, for example only 35 to 45% of himotmoistins, according to the distillation range of the oil fraction.

A further disadvantage of the straightforward refining of oil fractions is that the extracts usually contain a large amount of sulphurous sulfur, for example above 3% by weight, which impedes the use of these extracts in industrial practice.

These drawbacks are effectively overcome by the process of the present invention characterized in that the petroleum oil fraction, either as such or dewaxed, prior to the extraordinary refining of elevated pressure and temperature and in the presence of hydrogen or hydrogen-containing gas, with a heterogeneous catalyst capable of accelerating hydrogenation of condensed aromatic hydrocarbons, such as naphthalene, anthracene, phenanthrene and higher polycyclic aromatics, capable of accelerating the hydrogeination of sulfuric, nitrogen and oxygen-containing oil-containing substances to lower molecular or gaseous sulfur, nitrogen and oxygen compounds, or ¹ more condensed cores for hydrocarbons having a single aromatic nuclei and hydrocarbons having three or more aromatic nuclei, accelerating the spread of cyano-alkane-alkali hydrocarbons to isoalkanes other and accelerating isomerization of cyanolanic alkane hydrocarbons.

Suitable operating conditions for carrying out these structural-type conversions are in the pressure range of 1 MPa to 25 MPa, in particular in the pressure range of 3 MPa to 8 MPa, in the temperature range of 180-450 ^° C, preferably 280-400 ° C, at a space velocity, expressed as volume of liquid petroleum fraikcie zai unit time, the amount of fcatalyzátora, from 0.1 to 4.0 h ^_1, predinostine 0.2 to 1.5 ^h-1 and piri ipomere circulating hydrogen atom or • a gas obisaihujúcebo from 100 to 5,000 inoirimum volume per volume of liquid.

An oil catalyst is obtained from the reaction mixture leaving the reactor after separation of unreacted hydrogen, gas and low pressure liquid fractions, which is subsequently subjected to liquid extraction refining with setelective solvents. The low boiling liquid fractions can be used as such, or after fractionation, for pyirolysis, as a fuel component and for the production of lighter oils.

An advantage of the process according to the invention is that it allows to significantly increase the yields of the desired fractions in the extraction refining. The process is particularly effective in vacuum deistilate formulations with a mepriable structure type, i.e. with a high degree of bi- and polycondeinated aromatic hydrocarbons, for example above 30% by weight, containing chemically bound sulfur, nitrogen and oxygen. Therefore, from the above specific chemical premia, which are carried out in the presence of hydrogen in contact with the catalyst, the important reactions are in particular hydrogenation of condensed aromatic hydrocarbons to monoaromatics and cyclames, conversion of chemically bonding sulfur, nitrogen and oxygen in the molecule. these heteroatoms as well as the proportions of hydrocarbons having two condensed aromatic nuclei to monoaromatics and molecules having three or more condensed aromatic nuclei per molecule, supported thermodynamically at higher temperatures and less pressure in the guide.

Suitable catalysts for carrying out the desired broad-type transformations are metals, oxides of oxides, metal sulfides VI. and VIII. groups of the periodic array of elements deposited on alumina and / or on amorphous and / or crystalline aluminosilicate.

Preferred catalyst systems include oxides or toombinácie sínnilkotv Koivu-Co-Mo, Ni-Mo, Ni-W or Ni + Co + Mo + · metal-containing Ni and / or Co ¹ 1.5 to 5 wt.%, Preferably 2 5 to 3.5 wt.%, Mo 7 to 15 wt.%, Preferably 8 to 12 wt.%. and W 12 to 22 wt.%, preferably 15 to 20 wt.%, deposited on alumina or on amorphous and / or crystalline aluminosilicate. The crystalline aluminosilicate may be a zeolite having an SiO 2: AhO 3 ratio of at least 2.5.

From the realization mixture, after the gaseous and further boiling liquid fractions have been removed, so-called " an oil kaitalyte which, in comparison with the Si basin oil fraction, has mainly an increased content of alcanoes, cyclames, possibly moinaroimates, and a reduced content of condensed aromatic hydrocarbons, metal and toeteroatomic, i.e., an alkali metal salt; bound sulfur, nitrogen, and oxygen.

This oily catalyst is subjected to extractive refining with selective solvents. Extractive refining may be carried out in batch or preferably flow-through column extractors, with efficient fixed or movable installation, or in the mixer-judgment extruder apparatus. The relative movement of the hydrocarbon and solvent phases can be countercurrent or preferably countercurrent. The extrakia may be carried out without reflux, or preferably with an inoperative, isothermal or gadient temperature in the extractor, at temperatures from 40 to 150 ° C, preferably 60 to 130 ° C.

Suitable stable solvents and low-toxic liquid compounds containing functional groups or combinations of functional groups of alcohols, aldehydes, ethers, ketones, amines, nitriles, sulfides, sulfoxidoids, sulfones or mixtures of at least the wild-type compounds mentioned are suitable stable and low-toxic liquid compounds in the molecule. Particularly preferred selectively solvents for the phaipaline extract oil refining are furfutal and N-methylpyrrolidone or mixtures thereof. To increase selectivity, the solvents may contain water and / or glycols, such as mol-, di-, and triethyleneglycot, or mixtures thereof, in an amount of from 1 to 2. 0.1 to 60 wt.

The raffinates obtained according to this invention can be further treated by conventional automotive, turbine, electrical insulating and industrial oils, such as by curing, hydrogelating, adsorption refining. and additivating.

The following examples are provided to illustrate the invention. EXAMPLE

Eabian petroleum vacuum distillate made from sulfuric paraffinic petroleum with a density of 889 kg / m ³ at 20 ° C, a viscosity of 2,51 tnni% at 100 ° C, exceeding 22,8% by weight of hia polycyclic aromatic hydrocarbons and 1,6% The mass-sulfur sulfur was refined by countercurrent liquid extraction with N-methylpyrrolidone in an extractor with an efficiency of 5 theoretical extraction steps, at a weight ratio of N-methylpyroiliidone to vacuum distillate of 2.26: 1, at a temperature at 70 ° C vacuum distillate feed point. extractors 30 ° Celsius. After distilling off the solvent from the raffinate phase taken from the extractor, a raffinate having a density of 841 kg / m ³ at 20 ° C, a viscosity of 2.43 mm ² / s at 100 ° C, a content of bi- and polycyclic hydrocarbons of 0.6 %, a sulfur content of 0.42% by weight and a viscosity index of 125. The raffinate yield was 54.5% by weight. from vacuum distillate. The extract had a sulfur content of 3.0% by weight.

Example 2

The light petroleum vacuum distillate, characterized in Example 1, was dosed together with the N-methylpyrrolidone-containing gas together with the gas containing 80% by volume N-methylpyrrolidone prior to liquid extraction refining. hydrogen into a fixed bed reactor. The catalyst contained 2.8 wt% NiO and 14.7 wt% MoOs deposited on alumina. The reactor inlet was maintained at a temperature of 365 ° C, a pressure of 4.0 MPa, a volumetric loading of catalyst by vacuum distillate of 1 h ¹ and a gas to vacuum distillate volume ratio of 500 Nm ³ / m ³ . From the reaction mixture leaving the reactor, after separating the gas and distilling off the liquid fractions up to 300 ° C, an oil catalyst was obtained having a density of 870 kg / m ³ at 20 ^° C, a viscosity of 2.45 mm ² / s at 100 ° C and containing

12.3% by weight of bi- and polycyclic aromatic hydrocarbons and 0.03% by weight of sulfur in a 95% yield by weight of the vacuum distillate.

The oily catalyst was then refined with countercurrent liquid. extraction with N-methylpyrrolidone, similar to the 1 light vacuum distillate of Example 1, in an extractor with 5 theoretical extraction steps, at a temperature at 100 ° C at the inlet point of the solvent, at different heat grades of 252868 and at N-methylpyrrolidone ratio of which a rimimate was obtained at a temperature gradient of 35 ° Celsius and a weight ratio of N-methylpyrrolidone to a catalyst of 1.95: 1, the same having a density of 837 tog / im ⁵ at 20 ° C, a viscosity of 2.41 mm ² / s at 100 ° C, a content of bi- and polycytholite aromatic hydrocarbons of 0.5% by weight, a sulfur content of 0.02% by weight, and a viscosity index of 125, v. 68.3% by weight of toatalyte or 64.9% by weight of flood lightweight vacuum distillate. The sulfur content of the extract was 0.05% by weight. Example 3

Medium petroleum distillate obtained by the cylindrical distillation of sulfuric paraffinic petroleum, having a density of 940 kg / m ³ at 20 ^° C, a viscosity of 20,20 mm ² / s at 100 ° C, containing 36,7% by weight of bi- and polycyclic aromatic hydrocarbons; 2% by weight of sulfur was refined by countercurrent incapacitated refining of furfural in an extractor with an efficiency of 5 theoretical extrudation stages, at a furfural to distillate vacuum ratio of 3.60 ': 1, at a temperature at the solvent inlet point of 123 ° C and a vacuum inlet point · Distillate 96 ° C, i.e. at a temperature gradient in the extractor of 27 ° C. After distilling off furfural from the raffinate phase taken from the extractor, raffimate was obtained having a density of 893 kg / m ³ at 20 ° C, a viscosity of 12.76 mm ² / s at 100 ° C, a content of bi- and polycyclic aromatic hydrocarbons 2.3 % by weight, sulfur content

1.1 wt.% And viscosity index 110, 43.8 wt.% Vacuum distillate. The sulfur content of the extract was

3.1% by weight.

Example 4

The middle petroleum vacuum distillate, as described in Example 3, was fed together with hydrogen into a fixed catalyst reactor prior to the gasoline extraction refining with furfural. The catalyst contained

5.1% CoO 13.5% MoO2 deposited on alumina.

At the inlet to the reactor, a temperature of 380 ° C, a pressure of 4.0 MPa, a catalyst bed volume vacuum of 0.6 h ¹ and a hydrogen to vacuum distillate volume ratio of 1000 Nm ³ / m ³ were maintained. Reaitočinej from the mixture leaving the reactor, after removal of the gas and distilling off tovapailnýcih units to 320 · C, an oily-ANALYSIS Toat having a density of 910 kg / m ³ at 20 · C ^Q, visfcozite 13.71 mm ³ / s at 100 ° C , contain 19.2% by weight of bi- and polycyclic aromatic hydrocarbons and 0.05% by weight of sulfur in a yield of 88.6% by weight of the vacuum distillate.

The oily catalyst was then refined by countercurrent liquid extraction by fuirfuraloim, similar to the medium weight distillate in Example 3, in an extractor with a efficiency of 5 theoretical extr, at degrees of dissolution at 123 ° C, at various temperature gradients and pomeiro-fur fur. to a catalyst, a raffinate having a density of 878 kg / m ³ at 20 ° C and a viscosity of 11.92 mm ² / s was obtained at a temperature gradient of 33 ° C and a furfural weight ratio of 3.3: 1 to furfural. at 100 ^° C, bi- and ipolycyclic aromatic hydrocarbons content of 1.3% by weight, sulfur content of 0.04% by weight, and viscosity index of 110, in a yield of 67.5% by weight from the catalyst or 59.8% by weight from the flood medium, vacuum distillate. The extract contained 0.07% sulfur by weight.

Comparison of extracts at the same level of viscosity indexes shows that according to the invention, the yield of raffinate from light, vacuum distillate relative to the viscosity index · 125 and raffinate increased in the above examples 1, 2 and 3, 4. from a medium vacuum distillate relative to 36.5% by weight, with a viscosity index of 110. The higher yields at r-quality of the raffinates were achieved at a lower solvent to oil ratio. The examples also show the efficacy of the invention in reducing the sulfur content of raffinates and extracts.

Claims (4)

SUBJECT 1. Method of production of raffinates from petroleum oil fractions! characterized in that the petroleum fraction is contacted in the reactor, in the presence of hydrogen or a hydrogen-containing gas, with a heterogeneous metal or metal oxides catalyst or mixtures thereof and / or mixtures thereof and / or mixtures thereof prior to the gasoline extraction refining, either as such or dewaxed; sulphides of metals VI. and / or VIII. groups of the periodic element element present in the structure and / or deposited on alumina, or on amorphous aluminosilicate, or on crystalline aluminosilicate, or on mixtures of at least two of said carriers at a pressure of 1 to 25 MPa, preferably 3 to 8 MPa, at ambient temperature in the range of 180 to 400 ° C, preferably 280 to 400 ° C, at a volumetric rate expressed as the volume of the fired feed per part of the catalyst volume, in the range of 0.1 to 4 Ir ¹ , preferably 0.2 to 1.5 h ¹ and the ratio of hydrogen or hydrogen-withdrawing gas from 100 to 5,000 Nm ³ / m ³ , preferably 500 to 1,500 Nm ³ / m ^{3 of} liquid, oil-fired fuel feed, and 252868 emerging from the reactor after hydrogen separation, The gas and the reducing liquid fractions are subjected to a liquid-phase refined refinery by selective solvents or solvent mixtures. 2. S, according to claim 1, characterized in that the heterogeneous catalyst comprises ox'd or rotten metals Mo, W, Co, Ni or a combination of at least two of these oxides or sulfides and is capable of accelerating hydrogenation (condensed aromatic hydrocarbons, such as derivatives of naphthalone, aroma, phenanthrene and higher polycyclic aromatic hydrocarbons, capable of accelerating the ihydrogenation of sulfur-containing oil traternary molecules, up to and including oxygen, to lower molecular weight gaseous or liquefied sulfur, due and sulfur compounds, or disulphates or a plurality of condensed aromatic cores into hydrocarbons having a single aromatic core and hydrocarbons having three or more cores, or accelerating also the cleavage of cycloalkanic hydrocarbons into the isoalkane and isoimerization of the eyiclammonaldehyde hydrocarbons. 3. The method according to claim 1, wherein the selective solvents for the liquefaction extraction refining are compounds containing, in a molecule, fuming groups or combining functional groups of alcohols, aldehydes, ethers, ketones, amino, amides, sulfides, sulfides, sulfides, sulfides, sulfides, sulfides, nitrides, sulfides at least two of said compounds, preferably luirfural or N-methylpyrrolidone. 4. A method according to Claims 1 and 3, characterized in that the selective solvents comprise water and / or glycols.