DE1470605B2 - PROCESS FOR THE PRODUCTION OF WHITE OIL AND / OR PARAFFINA LIQUIDA - Google Patents

Description

Sludge components and additives are retained, and the residues that are still present are recovered of the original highly refined oil. The filtrate from the first stage can have additional columns Aluminum oxide are supplied, namely in the countercurrent principle, here by adsorbent and oil. By extracting the individual columns with a single low-boiling paraffinic solvent the adsorbed paraffinic hydrocarbons are extracted from the columns, ! while all polar naphthenic and aromatic compounds remain behind and ! Enrich sorbent, which is quickly blocked and deactivated. This must therefore be relative short operating times for regeneration are fed to an expensive incineration at 800 ° C, all polar naphthenic and aromatic compounds of the waste oil are destroyed.

In the method of the invention, however, the petroleum distillate is first hydrogenated, whereby the strongly polar compounds of the feed oil, such as. B. sulfur, oxygen and nitrogen compounds as well Olefins, which quickly and irreversibly ineffective the adsorbent of the subsequent adsorption stage would break down to compounds that have no or only very little polarity and therefore have no adverse influence on the adsorbent. The hydrogenated oil only contains paraffins, naphthenes and non-polar or low-polar aromatics and can therefore be used for the subsequent adsorption and elution. The structural change brought about by this hydrogenation leads to higher yields of paraffinic and naphthenic finished products.

, Advantageously, the paraffinic and naphthenic hydrocarbons with a low molecular weight aliphatic hydrocarbon, preferably pentane, eluted sequentially. It has proven advantageous to elute the aromatic hydrocarbons with a low molecular weight aromatic hydrocarbon, preferably benzene. Although benzene itself is not polar, it does elute the adsorbed aromatics, which may have a low polarity, due to its extremely good dissolving power for aromatic compounds combined with a very large concentration range. Solution equilibria are established which, due to the large amount of solvents available, are more on the side of the solution. Since the oil aromatics become more and more depleted of the adsorbent as the elution progresses, the difference in concentration between solvent and adsorbed aromatics becomes greater and greater, ie the equilibrium shifts more and more to the solution side and the last residues of adsorbed aromatics are finally desorbed. If, instead of benzene, toluene or xylene is used as the eluent for the aromatics, there is an additional displacement effect due to their polar character. The aromatics are expediently eluted with 100 to 400% of a low molecular weight aromatic hydrocarbon. After the aromatics have been eluted, the adsorbent can again be absorbed for the next adsorption.

In a preferred embodiment of the method according to the invention, after the elution the aromatics the aromatic eluent through a low molecular weight aliphatic hydrocarbon, z. B. pentane, displaced from the adsorbent. It will be a tightening the separation effect is achieved when the layer formed by the eluent for the aromatics is displaced by an intermediate run of eluent for the aliphatics.

If the resulting hydrogenation product has a higher viscosity, it is advisable to do this before adsorption with a low molecular weight, in particular

ίο aliphatic hydrocarbon, preferably pentane, to dilute. The elution processes can also take place at elevated temperatures up to the boiling point of the Eluent can be carried out. As a result of the elution, the multicomponent mixture becomes "oil" without any chemical transformations split into the compound classes paraffins, naphthenes and aromatics.

The yields of white oils and Paraffinum Liquidum are in the process according to the invention much larger than in one of the process steps alone, d. H. Hydrogenation or adsorption and Elution, or any of the conventional methods. Already the combination of a weak hydrogenation with adsorption and subsequent separation by elution leads to increased yields.

The properties of the successively eluted fractions are so good that only in the case of preparation after refining with oleum bleaching earth is necessary for Paraffinum Liquidum.

The aromatic fraction falls in greater purity with a significantly lighter color (ASTM 1-3), better Color fastness and a significantly lower content of paraffins and naphthenes than is the case with solvent extractions the case is. This means an increase in value compared to the aromatic fraction the extracts from solvent extractions and a significantly higher white oil yield.

The combination of hydrogenation and adsorption with subsequent selective elution thus offers great benefits. In order to take full advantage of these advantages, they are useful for both process stages to comply with certain procedural conditions:

The hydrogenation is advantageously carried out at temperatures between 250 and 400.degree. C., preferably 320 to 380.degree. The pressure can range from 5 to 150 kgf / cm ² , but is preferably 30 to 90 kgf ^{/ cm 2} . The throughput speed of the oil can be 0.1 to 5 vol. Oil / vol. The catalyst and hour are those of the hydrogen from 5 to 500 vol. H / vol. Oil. The hydrogen can be brought into action in a single pass or in a circuit.

The catalysts used are sulfur-resistant contacts based on the oxides and sulfides of the metals of the 8th group of the periodic table such. B. iron, cobalt, nickel, molybdenum and tungsten into consideration. A catalyst with the composition NiS-WS ₃ -Al ₂ O ₃ is very particularly suitable.

The hydrogenation product is removed by stripping with conventional stripping means, e.g. B. nitrogen or steam, in conventional apparatus at elevated temperatures of dissolved hydrogen sulfide, Ammonia and water are freed and can then be used for adsorption.

For adsorption and subsequent elution, the oil is used in a ratio of 0.1 to 0.6 kg Oil / kg adsorbent on a column with. Adsorption

given medium. Depending on the paraffinic content of the oil Compounds are now 100 to 200% of a low molecular weight aliphatic hydrocarbon, z. B. pentane, pumped through the column, the paraffins and naphthenes eluting in succession will. Instead of pentane, for. B. also butane, hexane and heptane. Butane must be because of its low boiling point can be worked under increased pressure.

The following adsorption conditions can be selected:

0.1 to 0.8 dm ³ oil / dm ² column cross-section

and minute

Adsorbent Highly active silica gel

Adsorbent grain size 0.1 to 1 mm

Temperature 20 to 60 ° C

The degree of separation depends on the number of units withdrawn from the column per unit volume Fractions of different sizes. The boundaries of the different fractions can be determined by means of refractive indices and UV fluorescence. the . Paraffinic fraction is the basis for Paraffinum Liquidum and only requires final treatment with 4 o / o oleum. The naphthenic fraction occurs as white oil and does not require any further treatment.

The glow of the oil recorded in the examples is the strength of the fluorescence in the visible spectrum of light. The appearance is determined by simply comparing the to. determining sample with a standard pattern based on the WOMA scale.

Further reported hot acid test is described in the DAB 7, page 761. It is in this case the color (Lovibond) determines an oil with sulfuric acid at 10 ^o C Min./100 after heating. The test result is a measure of the stability of the oil in question in the presence of sulfuric acid, ie a measure of the degree of refinement of the white oil.

example 1

A dewaxed Middle East spindle oil distillate of the quality data listed below is provided in Hydrogenated in the presence of a catalyst, stripped, adsorbed on a column of silica gel and fractionated eluted.

1. Analysis data of the feed oil

Density / 15 ° C (DIN 51 757) 0.912

Viscosity (DIN 51 560) .. ° E / 20 ° C 9.50

Color (ASTM D1500) 8

Infrared analysis (according to Brandes) *)

Approx

Cp

Q *

Sulfur (DIN 51 400)%

Iodine number (Wijs)%

Neutralization number

(DIN 51 558) mgKOH / g

Pour point (DIN 51 583) ⁰ C

18.0

59.5

22.5
2.65
6.51

0.10
-20

*) C ^, Cp

=%) Carbon in aromatic, paraf ^ p jj
Finnish, naphthenic bond.

In the hydrogenation of this oil, it is mixed with an excess of hydrogen and then up heated to the required reaction temperature. The mixture of oil and hydrogen is then made of passed up and down over the fixed beds of the catalyst, where the actual hydrogenation reaction expires. Then the excess of hydrogen is in two expansion stages from Separated oil; a certain amount of this can be returned to the hydrogen used. The J The oil relieved from the hydrogen pressure is then in the; Vacuum of about 100 Torr and at a tempe-! temperature from about 100 to 200 ° C by means of steam or;

ίο nitrogen in countercurrent of residues of dissolved hydrogen, freed from light hydrocarbons and from dissolved hydrogen sulfide or ammonia. Then the oil is at the same temperature and a vacuum of about 20 torr dried. The relevant column processes are expediently used for this purpose.

Hydrogenation conditions

Reactor temperature

Reactor pressure

Rate of delivery

Feed gas rate.
Cycle gas rate
Catalyst ...

36O ⁰ C

Effective surface ...

90 bar 0.1 vol.

Oil / vol. Catalyst / hour 175 v / v oil lOqVolH / VoLÖl Cylinder consisting of 3 to

8 «/ ο tungsten sulfide, 10 to

15% nickel sulfide, the remainder being y-aluminum oxide

Carrier 180 to 270 m ² / g

Analysis data of the hydrogenation product

Density / 15 ⁰ C 0.874

Viscosity / ° E / 20 ° C 4.48

Color (ASTM D 1500) 1

Infrared analysis

C _A

Cp
C.

18.0 60.0 22.0 0.04 5.0

Sulfur%

Iodine number (Wijs) '%

Neutralization number mg KOH / g 0.01

Calculation index

(DIN 53 491) n _D 20 ° C 1.4807 ■

SK number (DIN 51 553) volume percent 0.9

The hydrogenated and dried oil is then adsorbed on silica gel and separated into different fractions by eluting with solvents. For this purpose, 100% of the hydrogenation product is dissolved in 50% pentane and this solution is pumped through a column with silica gel (grain size 0.2 to 0.5 mm) at ^{a flow rate of 0.6 dm 3} solution / dm ^{2 column cross-section and minute} top down. The total amount of oil is to be limited to 0.36 kg oil / kg gel. To elute the paraffins and naphthenes, 50% pentane is then pumped onto the column without interruption and finally 300% benzene to elute the aromatics and to regenerate the silica gel. Such an adsorption, elution cycle can be repeated any number of times.

The following fractions are collected separately:

Pentane eluate with refractive indices n * § <1.4688

This fraction consists predominantly of paraffins and is obtained in an amount of 28% of the input Hydrogenation product. After a final treatment with 4% oleum and 3% fuller's earth, the product is in 95% yield get a Paraffinum Perliquidum, - that by the different pharmacopoeias and pharmacopoeias corresponds to the required specifications and has the further characterizing data:

Color ... +30 Saybolt

Schein WOMA .... free

Viscosity (20 ° C) cSt .... 32.2 ■ ■

Density (15 ° C) ........... '0.858

Hot acid sample 1.8 yellow to

(DAB-7, p. 761) ...: ... 0.7 red Lovibond UV fluorescence. negative

Pentane eluate with refractive indices n% ° = 1.469 to 1.4785

This fraction contains paraffins and naphthenes with side chains in the molecule. It follows in the elution with pentane of fraction 1 immediately. It is a light white oil and does not require any further processing:

Color + 30Saybolt

WOMA 1 + certificate

Viscosity (20 ° C) cSt 32.8

Density (15 ° C) 0.865

Cold acid test

(House method) *) 3 + Ostwald

IR analysis

Cp% 61.5 ■:

C _n % 30.0

SK number 0

Color Ostwald volume percentage 3+

Refractive index nf 1.4728

Iodine number (Wijs) 3.5

*) 5 cm ^{3 of} sulfuric acid (96%) and the corresponding oil are mixed intensively for 1 minute at 20 ° C. The sulfuric acid is then allowed to settle and its color is measured according to the Ostwald scale.

Benzene eluate

The benzene eluate contains compounds with an aromatic or slightly polar character. That after Distilling off the benzene remaining oil has the following data:

ColorASTM 1

Viscosity (20 ° C) cSt 48.5

Density (15 ° C) 0.9224

Furfural number by volume 7.5

Sulfur% 0.16

IR analysis

C _A :% 45.5

C _n . »/ Ο 3.5

SK number. '.. 9.9

Color Ostwald .... ".. Volume percentage 10

Refractive index n ^z g 1.5188

'Iodine number (Wijs) 13

Yields and quantities of oleum required based on the distillate:

PL 26% (1.1 vol. Oleum)

White oil 41% (no oleum)

Aromatics' * 29% (no oleum)

. 4% hydrogenation and refining loss

Example 2

If the pentane eluate in Example 1 is collected in a fraction and divided into paraffins and naphthenes dispensed with what is technically most simple. is most, one obtains according to the process conditions of Example 1 a white oil to 70% of the hydrogenation product with the following data:

Colour ....; , + 30Saybolt

^ao ScheinWOMA 1

Viscosity (20 ° C) 32.6 cSt

Density (15 ° C) '.. 0.864

Cold acid test 3 Ostwald

UV fluorescence positive

This oil can be seen as the final quality.

Yields based on the distillate

White oil 29% (without oleum)

Light aromatics ...... 29% (color 1 ASTM)

Hydrogenation loss 2%

By refining this white oil with 4 times 7.5% oleum and 3% bleaching earth, the yield is 91% receive a Paraffinum Perliquidum according to the specifications of the various pharmacopoeias. It can be characterized by the following data:,

Color +30 Saybolt

WOMA free

Viscosity (20 ° C) 32 cSt

Density (15 ° C) 0.862

Hot acid sample ..... '2.1 yellow to

1.0 red Lovibond UV fluorescence negative

Yields based on the distillate

Paraffinum Liquidum.
Light aromatics

62% (approx

21% oleum) 29% (color 1 ASTM) 9% hydrogenation and

Refining

losses

Example 3

A dewaxed Middle East spindle oil distillate was prepared in the presence of a catalyst as follows Conditions hydrogenated:

Temperature 350 ⁰ C

Pressure 40 kg / cm ²

Throughput rate ... 0.6 V oil / V

catalyst

and hour

Feed gas rate 100 V / V oil

Circulation gas rate 100 V / V oil

309 525/428

The catalyst used had the following composition:

2 to 5% CoO
4 to 12 ° / o MoO ₃
6 to 20% Fe ₂ O ₃
Balance: 7-Al ₂ O ₃

The analytical data of the feed oil and that of the hydrogenation product are the same as in Example 1. The product obtained under these hydrogenation conditions was, as listed in Example 1, by Elute separately.

1. Pentane eluate with refractive indices n ² g <1.4678

This fraction amounts to 24% of the hydrogenation product and is added with 7.5% oleum and 3% fuller's earth a refined oil that, according to the pharmacopoeias and pharmacopoeias, is called Paraffinum Perliquidum is. The following analysis data are given:

Colour ...-. . ". + 30Saybolt

WOMA free

: Viscosity (20 ° C) 38.2 cSt

'Density (15 ° C) 0.868

Hot acid sample 2.3 yellow to

l, 3 red Lovibond

UV fluorescence negative

2. pentane eluate with
Refractive indices nf = 1.4688 to 1.479

This fraction, which is obtained in an amount of 30% of the hydrogenation product, can be obtained in 95% yield Refine with 4% oleum and 3% fuller's earth to the following white oil:

Color + 30Saybolt

WOMA 1 + certificate

Viscosity (20 ° C) 39 cSt

Density (15 ° C) 0.870

Cold acid test 6 Ostwald

3. Benzene eluate

After distilling off the benzene, a product with the following data corresponding to 46% of the Obtained hydrogenation product:

Color 3.5 ATSM

Viscosity (20 ° C) 80 cSt

Density (15 ° C) 0.975

SK number 29 volume percent

Furfural number 23 percent by volume sulfur 3.15%

Total yields and oleum required quantities, based on the distillate:

PL 22%

(1.8% oleum)

White oil 28%

(1.2% oleum)

Aromatics 45%

5% hydrogenation and refining losses

Claims (5)

1 2 very considerable in the degree of refinement and thus also in patent claims: differ in the properties. Therefore, up to now one had to obtain highly refined products 1. Process for the production of white oils White oils from mineral oil distillates of the final and / or Paraffina Liquida from Mineralöldestilla- 5 adsorptive treatment with fuller's earth, which is only used for th by hydrogenation of the mineral oil distillate, removal of the last traces of unwanted streaks of the hydrogenation product and treating constituents "served, a solvent extraction, with an adsorbent, thereby refining with considerable amounts of oleum and a indicates that a dewaxed neutralization takes place upstream. This four-stage Ge mineral oil distillate io extraction process used as input material is complex and brings with it and the other disadvantages adsorbed on silica gel entail considerable oil losses, ten mineral oil distillate successively paraffinic, It is also the desulfurization of kerosene naphthenic and aromatic hydrocarbons by means of hydrogenation, steam stripping substances are eluted. and subsequent washing out with an aqueous one 2. The method according to claim 1, characterized in 15 solution of lead oxide with the addition of lead acetate indicates that the paraffinic and naphtha temperatures of 121 to 204 ° C, then with vernic hydrocarbons with a low-dilute sodium hydroxide solution and finally with water bemolecular aliphatic hydrocarbon, (British Patent 734 047). So it is preferably pentane, not all of the hydrates are eluted one after the other in this process either. ^the product is adsorbed, but only the 3 .. The method according to claim 1 or 2, thereby nenden proportions. characterized in that the aromatic carbons The invention is to a process for the extraction of hydrogen with a low molecular flavor of white oils and / or paraffina liquids gematic Hydrocarbon, preferably notify, which works according to a completely different principle, be eluted. 25, the extent of the technical disadvantages of the 4. The method according to claim 1 to 3, characterized in that the four-step process is characterized quite considerably, that after the elution of the reduced and consequently also essential host aromatics the aromatic eluent is more economical. by a low molecular weight aliphatic The object of the invention is at a Hydrocarbons, e.g. pentane, from the Adsorp process of the type described above thereby is displaced. solved that a dewaxed mineral oil distillate as 5. The method of claim 1 to 4, wherein feed is used and from that on characterized in that when higher-viscosity silica gel accumulates, mineral oil distillate adsorbed after-hydrogenation products these before adsorption are paraffinic, naphthenic, and aromamitic a low molecular weight, in particular 35 table hydrocarbons are eluted, aliphatic hydrocarbon, preferably the eluted fractions can partly as final pentane, be diluted. quality are considered or only required a final treatment with small amounts of oleum and fuller's earth to achieve the desired quality 40 give. It is true that aromatic and paraffinic hydrocarbons have already been obtained by adsorption and Desorption with specific for both groups The invention relates to a method for thread-inducing means separately (British patent specification tion of white oils and / or paraffina liquids from 714 614). In this case, a gas oil is initially completely on Mineral oil distillates are adsorbed by hydrogenation of the mineral 45 silica gel, then the non-oil distillates, Stripping the hydrogenation product and aromatic hydrocarbons using Treat with an adsorbent. of a low molecular weight paraffinic hydrocarbon White oils belong to a well-known class of oxygen-eluted and finally the aromatics with I oils, which, depending on the degree of refining , are desorbed as a polar solvent, such as water, ketones \ lubricating oils (e.g. in the precision engineering industry, 50 and alcohols The polar compounds (as watch oils and sewing machine oils), as cosmetic oils, however, are irreversibly used by silica gel or as pharmaceutical oils. sorbed and can no longer be eluted. The j They normally represent light-colored oils with colors. Adsorbent is therefore after saturation with the values between -16 and +30 Saybolt. called strongly polar compounds unusable; Under Paraffina Liquida are high-55 and must be discarded. As the procedure; understood refined mineral oils, which characterize this patent specification the extraction of aromatics; The upstream connection is prohibited books or pharmacopoeia are specified. a hydrogenation stage that covers a large part of the In a known method for the preparation of polynuclear aromatic hydrocar- '■ desired electrical insulating oils (British Patent Specification 60 hydro- to naphthenes and paraffins via lead 887) is first hydrogenated and a mineral oil would. This would result in a considerable exhaustion of the hydrogenated product with a solid adsorption loss of aromatics. B. Fuller's earth, bauxite and clay, treated There is also a chromatographic filtration delt. The hydrogenation product is not ad- of used waste oils via adsorbents, sorbed, but the remaining, unwanted 65, for example aluminum oxide, known (German Components, d. i.e., it is a simple interpretation document 1 035 835). They are always in the Bleaching earth treatment. In addition, it should be noted that used oil contains polar oxidation or digestion electrical insulating oils and paraffina liquids are combustion products, unsaturated cracking products,