DE1594421B2 - MINERAL OIL-BASED INSULATING OIL AND PROCESS FOR THE MANUFACTURING OF A MINERAL OIL-BASED INSULATING OIL - Google Patents

Description

2. A method for producing an insulating oil according to claim 1, characterized in that the heavy cycle gas oil is hydrogenated before or after being mixed with the mineral oil.

3. A method for producing an insulating oil according to claim 2, characterized in that the heavy cycle gas oil fraction is subjected to a distillation to remove the constituents, which boil below 350 ° at atmospheric pressure.

4. A method for producing an insulating oil according to claim 2 or 3, characterized in that that the heavy "gas oil fraction is dewaxed before its addition to the mineral oil.

5. A method for producing an insulating oil according to any one of claims 2 to 4, characterized characterized in that a heavy gas oil fraction is used as an additive to the mineral oil, which previously has been enriched in aromatic constituents by solvent extraction.

6. A method for producing an insulating oil according to any one of claims 2 to 5, characterized in that that the heavy gas oil fraction is treated with acid prior to its addition to the mineral oil.

The invention relates to mineral oil mixtures which are used as insulating oils and which are advantageous in addition to others Properties have exceptional resistance to oxidation. Furthermore, the Invention a process for the production of these insulating oils.

It is known to produce insulating oils from a mineral oil and an oxidation-resistant additive. According to the invention, this additive, which in amounts of 0.1 to 10 percent by weight, based on the mineral oil used is from a hydrogenation product of a heavy cycle gas oil. Through this oil mixtures with a high aromatic content are obtained.

Special fractions of a naphthenic crude oil that were obtained by distillation have already been ^{refined by treatment with} sulfuric acid, sodium hydroxide solution and an absorbent in order to obtain products with a high aromatic content. The use of a heavy cycle gas oil with defined physical data, which has been hydrogenated, could not be inferred from the relevant literature.

It is also known to produce insulating oils by mixing a ordinary mineral oil with a synthetic oil, which in turn by condensate _sat i _O n of polynuclear aromatic hydrocarbons having a produced by the Fischer-Tropsch process hydrocarbon fraction using a Friedel-Crafts catalyst obtained has been.

Finally, an insulating oil is also known which consists of a mineral oil mixture with the addition of a carbon-hydrogen mixture which has been obtained by cracking, catalytic hydrogenation or alkylation. This additive cannot be compared with the additive according to the invention. The well-known additive to boil 160-350 ⁰ C, while the boiling range of the additive is in accordance with the invention 350-660 ° C.

In contrast, the insulating oil according to the invention consists of a mineral oil, preferably a raffinate of a light distillate, and 0.1 to 10 percent by weight, based on the weight of the mineral oil, of an oxidation-preventing hydrogenation product of a density between 0.99 and 1.10 at 15 ^° C. heavy cycle gas oil having a viscosity of 2 to 8 cSt at 98.9 ° C, an aniline point on the order of 25 to 80 and a distillation range of 180 to 660 ° C at atmospheric pressure.

The hydrogenation of the heavy cycle gas oil removes sulfur and oxygen compounds and the unsaturated components are saturated. The oil obtained in this way is very stable and shows a very low tendency to form sludge without any other properties common to transformer oils are required, here would have been worsened. The comparison tables below show the technical progress achieved by the new transformer oil, in particular with regard to the acid number and the tangent of the electrical loss angle.

The heavy cycle gas oil fraction used as a starting product in the context of the invention is in the petroleum refinery in fission processes, ζ. B. in the catalytic fluidized bed splitting obtained. at In addition to the light products, heavy fractions are also formed in this process are referred to in technology as "light cycle gas oil" and "heavy cycle gas oil". These factions are very rich in aromatics and very heat-resistant.

In general, the characteristic values of this fraction are within the following limits:

^{Density at 15 C} 'S / ^cm · ■ °' ^{990 to 1} ^
Viscosity at 98.9 ° C, cSt 2 to 8

Aniline point, ⁰ C 25 to 80

Distillation range, ⁰ C .. between 180 and 660

(Temperatures converted to atmospheric pressure)

3 4

Preferably, the heavy cycle gas oil is used before after performing one or more of the above

added to its addition to the oil base by distillation in the treatments described to the oil base

Atmospheric pressure topped so far that the under. The addition is preferably made after the

350 ⁰ C boiling components are driven off. Oil base treated with a selective solvent

In addition, the heavy cycle gas oil has been used before 5 in order to reduce its aromatic content,

its addition to the oil base, preferably dewaxed, and as a rule it takes place before the final treatment,

if the finished oil has a cloud point (ASTM e.g. before treatment with natural or active

D 97-47) should have less than +5 ⁰ C. To z. B. fourth earth or preferably before treatment

an oil with a cloud point of -15 ⁰ C to with hydrogen.

must be a heavy cycle gas oil with an io. The oil base can also be used with the untreated

Pour point of -15 ° C can be used, and this or one or more of the above-described

can be treated by known dewaxing processes in benen processes heavy cycle gas oil

a yield of, for example, 80 to 85% are mixed, after which the two constituents

be won. individually for themselves such a finished treatment

The dewaxing treatment changes in none of the 15 throws.

Way the other properties that the finished The amount of treated or added

Oil mixture through the addition of the heavy cycle untreated heavy cycle gas oil is pre-

gas oil are awarded, in particular not the preferably 1 to 5 percent by weight, based on the

Resistance to oxidation. Oil base.

To the aromatic content of the heavy circulatory 20
to increase gas oil, it can, regardless of whether

it is or is not dewaxed, prior to its addition to B e i s d i e 1 1 Oil base by treating with a selective solvent, e.g. B. phenol, are refined so that

an extract yield of 80 to 95%> preferably 25

from 90 to 95%> is obtained. The starting material is a fluidized bed

The heavy cycle gas oil is preferably split with heavy cycle gas oil, regardless of whether it has been dewaxed with a viscosity of 2 cSt at 98.9 ° C. This starting material or has been treated with a selective solvent after various pretreatments or not, before its addition to the oil base 30 a light raffinate to obtain various a mild acid treatment, ζ. B. insulating oils added to a treatment. The light raffinate is obtained at 5 to 20%> preferably 8 to 12% 98 percent by subjecting, for example, a light Tia Juana sulfuric acid. The acid tars are distillate so refined with phenol that a then, z. B. by hot decanting (at 80 to 100 ⁰ C), raffinate separated with a viscosity weight constant of, and the acid raffinate is obtained, for example with 35 0.822 (raffinate yield 55%). aqueous or alcoholic sodium or potassium hydroxide solution, the oils consisting of the raffinate alone and neutralized, then washed with water and dried the mixtures of the raffinate and the various, z. B. with the help of natural adsorption products specified above are used for the purpose of finished earth (silicoaluminate). position a mild hydrogenation among the following

The heavy cycle gas oil as such or subject to 40 conditions:

Temperature 280 ⁰ C

Pressure .' 60 at

τ-, u. ι. ■ λ- t: I parts by volume of oil / hour. \. ,, ",," ,,,

Throughput rate,, V / V / hr 1

\ Catalyst room part /

_ ..,.,.,. / Space part hydrogen at NTP / hour \., "

Flow _velocity: 150

\ Room part oil / hour /

Cobalt molybdate catalyst

Aluminum oxide

(3.5% CoO + 12.5%

MoO ₃ )

To determine the resistance to oxidation of these divorces and the percentage loss of strength

The so-called B. B. C. test is used to determine the cotton thread. In addition, after

for 1000 ml of the oil in a copper pot, the dielectric loss in 168 hours, i.e. H. the The presence of a cotton thread heated to 110 ° C. 65 tangent of the loss angle of the oxidized oil

will. Determinations are made after 72 hours and after 168 hours.

The NPA Color (ASTM D-155) and Acid Number The results are from the following tables

(ASTM D-947) of the oil as well as the amount of Ab- can be seen.

Tabel

properties

A. 11th B. 18th 7th
0.224
0.095
0 5
0.168
0.064
0 8+ 6V ₂ 0.560
0.275
5
1 0.402
0.095
10
0.4200

Products

Tag Robinson Color

BBC test
After 72 hours

ASTM color

Acid number (mg KOH / g)

Mud, g

° / ₀ Loss of strength of the cotton thread after 168 hours

ASTM color

Acid number (mg KOH / g)

Mud, g

° / ₀ loss of strength of the cotton thread

Tangent of the loss angle

Product A.
Product B

22.5

0.063
0.008
0

0.126

0.048

0.1450

24

0.042
traces
0

V ₂
0.084
0.023
20th
0.0418

23

0.084 0.012 0

V ₂
0.168 0.037 24
0.0450

Light Tia Juana raffinate + 4% dewaxed heavy cycle gas oil.
Corresponds to product A, after treatment with 2% activated bleaching earth (Actisil) at 85 ° CV ₂ hour while passing nitrogen and 2 ° / ₀ of natural bleaching earth (Clarsil PCS) at 110 ⁰ C V ₂ hour while passing nitrogen.

Product C: Corresponding to product A after treatment with hydrogen at a pressure of 60 bar flow rate VVH = 1 gas ratio 150.

Tabel!!

C _2: 28O ⁰ C
C ₃ : 300 ° C

properties

BBC test
After 72 hours

ASTM color;

Acid number (mg KOH / g)

Mud, g

% Loss of strength of the cotton thread After 168 hours

ASTM color

Acid number (mg KOH / g)

Mud, g

° / o loss of strength of the cotton thread

Tangent of the loss angle

B. Products D. E. "A. A- C. 3V ₂ - 3V ₂ - 3 0.063 4- 0.063 0.063 0.098 0.013 0.084 0.020 0.014 0.008 0 0.021 0 0 0 5 0 4V ₂ - 4V ₂ - 4+ 0.119 4V ₂ - 0.105 0.098 0.224 0.050 0.112 0.040 0.042 0.055 0 0.068 22nd 12th 10 0.0605 19th 0.0620 0.0740 0.2750 0.0635

0.042 lanes 0

V ₂

0.084 0.023 20
0.0418

Product A: Hydrogenated light raffinate at 28O ⁰ C, a pressure of 60 bar, flow velocity VVH = 1,

Gas ratio 150.

Product B: corresponding to product A with separately hydrogenated B) = 250 ⁰ C - ° / ₀ 1.76 sulfur

Product C: dewaxed heavy cycle gas oil C) = 280 ° C -% 1.48 sulfur

Product D: (hydrogenation at 60 bar, flow rate D) = 320 ° C. -% 0.79 sulfur

Product E: VVH = 1, gas ratio 150) E) = 350 ° C -% 0.40 sulfur

Product F: hydrofined mixture (light raffinate -f- 4% dewaxed heavy cycle gas oil) 280 ° C, 60 bar, flow velocity VVH = 1, gas ratio 150.

Example 2

The starting material is a heavy circulating gas oil obtained by fluidized bed splitting a viscosity of 3.88 cSt at 98.9 ° C. This heavy cycle gas oil (C) becomes the following Products manufactured:

(C 1) Dewaxed product

Manufactured by dewaxing the heavy cycle gas oil (C) by cooling a solution of Space part of heavy circulating gas oil (C) in 3 space parts sec. Bring butyl acetate to -25 ° C and filter off with a yield of 85% -

(C 2) Acid treated dewaxed product

Made by treating C1 with 10% 98% sulfuric acid, decanting the acid tars at 90 ° C., neutralizing the acid raffinate with aqueous sodium hydroxide solution, washing with water and drying by means of natural adsorption earth (yield 75%, based on C 1).

7 8

These different products have the following characteristics:

product C2 C. Cl 1.015 1,000 1.010 3.93 3.88 4.05 178 174 174 45.8 56.6 46.8 -11 +33 -15 1,580 1.5764 1.5881 265 260 265 64.5 61.75 69.0 2.55 2.23 2.48 0.005 0.095 0.117

Density at 15 ° C, g / cm ³

Viscosity at 98.9 ⁰ C, cSt

Flash point (open vessel), ° C

Aniline point, ⁰ C

Cloud point (ASTM D 97-47), ° C ...

Refractive index at 70 ° C

Average molecular weight

Aromatic carbon content (by Ultrarotbestimmung) ^_0/0

Sulfur, weight percent

Nitrogen, weight percent

Using the dewaxed product C1 and the acid treated dewaxed one Product C 2 is converted from the light raffinate described in Example 1 as an oil base into isoheric oils manufactured.

The oils consisting only of the light raffinate as well as the mixtures of the oil base with the relevant ones Products are under the conditions of the hydrogenation carried out in Example 1 of the final treatment subject.

The oxidation resistance of these insulating oils is determined as described in Example 1

B. B. C. test and a so-called C. E. I. test method, in which by 25 g of oil in a glass tube in the presence of a copper wire at 100 ° C oxygen at a speed of 11 / hour. passed through will. After 164 hours, the amount of deposits and the acid number of the oxidized Definitely oil. These studies provide the following results:

none additive
4 »/ ο Cl 4 ° / oC2 BBC test
After 72 hours
NPA color 3
0.098
0.008
0
4+
0.224
0.055
10
0.2750
0.220
0.020 2
0.042
traces
0
0.084
0.023
20th
0.0418
0.056
0.010 2
0.042
traces
0 Acid number, mg KOH / g
Deposits, g
Loss of strength of the cotton thread,%
After 168 hours
NPA color 0.100
0.018
20th
0.0650
0.022
0.008 Acid number, mg KÖH / g
Deposits, g
Loss of strength of the cotton thread,%
Tangent of the loss angle
CEI test
Acid number, mg KOH / g
Deposits, g

309 512/442

Claims (1)

Patent claims 1. Insulating oil, consisting of a) a mineral oil, preferably a raffinate of a light distillate and b) 0.1 to 10 percent by weight, based on the weight of the mineral oil, of an antioxidant Hydrogenation product of a density of 15 ° between 0.99 and 1.10 g / ccm, a viscosity at 98.9 ° of 2 to 8 cSt, an aniline point on the order of 25 to 80 ° and a distillation range Heavy cycle gas oil having an atmospheric pressure of 180 to 660 °.