DE2457467A1 - METHOD OF CATALYTIC DEWAXING FOR THE MANUFACTURING OF INSULATING OILS OR REFRIGERATION MACHINE OILS - Google Patents

Description

PATENT LAWYERS

DR.-ING..VON KPclSTSI? OR, -iNG. SCHÖNWALD 2457467 DJL-ING. TH. MEYER DR. FUES DiPL-CHEM. ALKK VOM KREISLE » DJPL-CHEM. CAROLA KELLER DR.-ING. KLÖPSCH DIPL-ING. SELTINQ

5 COLOGNE 1, DEICHMANNHAUS

Cologne, J. December lu / Ax

The Briti s h Petroleum Company Limited, Britannic House, Moor Lane, London SG2Y 9BU (England).

Process for the 'catalytic! Dewaxing for the production of insulating oils or refrigeration machine oils

The invention relates to the manufacture of certain Special oils, namely from insulating oils and refrigeration machine oils, from petroleum fractions.

Insulating oils that are used, for example, in transformers, cables, Switches and capacitors are used "must have a low flow point, good resistance to oxidation, good insulating properties and, in certain cases, good ones Have gas absorption capacity »They are usually made from naphthenic petroleum fractions because these fractions usually have low pour points, low levels of sulfur (this is for resistance to oxidation important) and relatively high aromatics "contents (which are important for the gas absorption capacity are). Refrigerating machine oils must also have low pour points and good resistance to oxidation and are also normally made from naphthenic petroleum fractions. The procedures that normally used to bring naphthenic petroleum fractions to the high quality required Insulating oils for electrical engineering purposes or both

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Refrigeration oils ^ is required, the given- " if necessary dewaxing and dewaxing 2, ur lowering of the pour point and either the hydrocatalytic Treatment, acid treatment or solvent extraction to remove sulfur compounds and other unstable connections and to give the necessary stability.

In contrast, paraffinic petroleum fractions have been used until today considered unsuitable starting materials because they usually have high pour points and high sulfur contents exhibit. The high pour points cause particular difficulties because it is difficult if not impossible is, with the help of the usual methods of dewaxing and dewaxing with solvents or urea "to dewax and dewax to the required degree. It is recognized that the high sulfur content, through hydrocatalytic treatment, Acid treatment or solvent extraction lowered: could, but doubts remained as to how Influence of the treatment on the quality of the finished product

OilS. - ';

However, haphthenic petroleum fractions are particular scarce in Europe, so that there is a great need for a process which is the production of insulating oils and refrigeration oils from paraffinic petroleum fractions. The invention is a satisfactory process in which the required product quality is achieved through catalytic dewaxing and dewaxing is achieved. This is surprising in view of the prejudice against such a procedure.

The method according to the invention for catalytic dewaxing for the production of insulating oils or refrigeration oils is characterized in that petroleum fractions with an original pour point of -3 ° to +21 ⁰ G, an original sulfur

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■ ■ - 3 - ■

content of 0.1 "to .3 Gew .- ^ o and a viscosity of 1.5 to 4 cSt at 99 ° C in the presence of hydrogen with a catalyst in contact, which a crystalline mordenite with reduced alkali metal content and a or. Several hydrogenation components incorporated into the mordenite from groups VIa and VIII of the periodic table, and thereby lowering the pour point of the fraction and subjecting the fraction to a treatment by which at least 50% by weight of the sulfur are removed and its resistance to oxidation is increased, and a product wins which has a pour point of not more than -30 ⁰ C, preferably of not more than -50 C, and a viscosity of 1.5 to 4 cSt at 99 ° C.

The pour point and the sulfur content of the starting material are in the ranges which are normally customary for paraffinic petroleum fractions with the viscosity range mentioned. The actual ASTM cut points of a paraffinic crude oil required to obtain a fraction with the required viscosity may vary somewhat, but are normally in the range from 260 to 400 ^° C. Particularly suitable; Fractions are the top fractions of vacuum distillation columns. .

The acid treatment, solvent extraction or hydrocatalytic treatment in question, but the former Procedure is not preferred because of the problems in removing the acids »It should be noted that that the process for sulfur removal before or after the process for lowering the pour point can be carried out.

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All of the above sulfur removal processes take care of aromatics as well as sulfur compounds. remove «However, it was found that this removal of aromatics has no adverse effect. This is in view of the fact that insulating oils and refrigeration oils, made from naphthenic starting materials are generally substantial Containing amounts of aromatics, and that the paraffinic starting materials used according to the invention have relatively low original aromatic contents, to be regarded as surprising.

The procedure for lowering the pour point is hereinafter referred to as hydrokatalytiscb.es dewaxing and

designated. This is a well-known process, which is described, for example, in British Patents 1,088,933 and 1,134,014. j

The wax in these lighter fractions is a crystalline wax or paraffin wax. It consists of-; for example from η-paraffins or slightly branched paraffins and is selectively to lower-boiling Paraffins, especially to C ^ and C paraffins, cracked. The selective breakdown of the paraffin wax hydrocarbons is due to the type of mordenite based Catalyst attributed to the selective attack on these hydrocarbons, but not to. favors and promotes the other hydrocarbons present in the starting material. !

Pur the hydro catalytic dewaxing, the following process conditions are: temperature from 250 to 50O ⁰ C, pressure 7 to 200 bar (gauge pressure), space velocity up to 20 V / V / hr, supplied 0.1.

3 3 Amount of hydrogen 90 to 3600 nr / ar starting material.

The following conditions are preferred for hydrocatalytic dewaxing:

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Solvent hydrocatalyst extraction after table bath catalytic treatment or solvent dewaxing

traction before catalytic dewaxing

Temperature, ⁰ G 350 - 430 270 - 400 pressure (manometer

pressure), bar "50 - 200 20-100

Space flow velocity,
V / V / h .0.5-5 0.5-10

Hp gas rate, m ⁵ / m ⁵ 1000-2500 500-1500

While it would be possible to outgrow hydrokatalytisch and then a hydrogenation treatment to _remove: make sulfur compounds, but is used in the hydrogenating treatment at times, the tendency to formation of wax to a potential growth '. turbidity problem leads. The wax can come from the breakdown of sulfur compounds and other unstable compounds; ties originate. Furthermore, if the hydrogenation treatment is done first, the low sulfur product can be hydrocatalytically dewaxed under relatively mild conditions. j

The expression "crystalline mordenite with reduced alkali metal content" denotes a mordenite with an alkali metal content of less than 3% by weight ^. other metal cations, for example group II metal cations, especially magnesium or rare earth metal cations, are balanced. However, a "decationized mordenite", ie a mordenite with a deficit of metal cations, is preferably used. Using another term, these mordenites are referred to in the art as "hydrogen mordenite" since it is believed that metal cations that are removed are caused by water

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Substance ions are replaced. However, since it is not possible is, the presence of hydrogen ions in zeolites the exact structure remains doubtful. A cation deficiency, on the other hand, can be determined by analyzing the im Zeolite metal elements present can be easily measured.

Natural or freshly made synthetic mordenite has the formula

1 Me ₂ O: "Al ₂ O ₅ : 9-11

in which Me is a metal cation, η is the value of the ^: cation and X varies between 0 and 7 depending on the temperatures that the sample has passed through during its production. Me is generally sodium which, in one of the common forms of decationization of sodium mordenite, is exchanged for ammonium cations by means of base exchange. The ammonium form is then heated, leaving the hydrogen form or decationized mordenite. In the second method, the mordenite can be treated with a mineral acid, for example hydrochloric acid or sulfuric acid, in order to decationize the mordenite directly. A combination of acid treatment and aramonium treatment can also be used.

The decationized one used for the purposes of the invention Mordenite preferably has a silica / alumina ratio that is higher than normal and is at least 14-21. In special attempts were Ratios up to 90: 1 reached so that 100: 1 may be the practical upper limit. Particularly preferred silica / alumina ratios are in the range from 14s1 to 50: 1.

It has been found that certain decationization "treatments Aluminum as well as the expected metal ca-

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removed. The for For the purposes of the invention used mordenite, the silica / alumina ratio of which is higher than normal, by treating a mordenite containing metal cations, in particular JTatriummorden.it, with a strong acid, e.g. sulfuric acid or hydrochloric acid, with a strength of 5 "to 50 wt .- $, preferably in 10: "up to $ 20% by weight. A single treatment or two or more consecutive treatments: can be carried out with acids of the above-mentioned concentrations *

Appropriate is a method of treatment "in which the Mordenite is treated with acid under reflux for a period of 2 to 12 hours.

In decationized mordenite, the content of remaining metal cations, for example, should the content of Watriumkationen, less than 3 wt .- $, preferably less than 1.5 wt. -Io amount of mordenite.

It should be emphasized that mordenites whose silica / alumina ratio is higher than normal, the Preserve the crystal structure of the mordenite and in terms of physical strength, stability or crystallinity are not significantly changed.

A platinum group metal is preferably used as the hydrogenation component, in particular platinum or palladium, used, which is preferably added by ion exchange will. The amount of platinum group detail lies preferably in the range from 0.01 to 10 wt .- ^, in particular in the "range of 0.1 to 5% by weight. Good results however, also with iron group metals, particularly nickel, obtained in similar amounts how. the platinum group metals can be used. Mixtures of certain metals and compounds of the groups VI and VIII, e.g., cobalt and molybdenum, can also

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be used.

Before use, the catalyst is used to remove • any water and ligands that may adhere to the Hydrogenation are bound, preferably at a Calcined temperature of 250 to 600 C, for example.

The product of dewaxing can be at any suitable and appropriate point of the procedure to be distilled to light ends that are below the boiling point of the Boil starting material to remove. As already mentioned, these are mainly C ~ - and C. paraffins, which are used as starting materials for Petrochemical or as liquefied petroleum gas (LPG) are suitable.

If a solvent extraction is carried out, sulfur dioxide / benzene are suitable solvents, Phenol, glycol or, preferably, furfural. The solvent can be used in a fixed extraction apparatus or a turntable extraction apparatus with 1 to 20 theoretical extraction stages can be used. The main process variables are the solvent / oil volume ratio, which can be 50 to 300, in particular 100 to 200, and the temperature gradient in the column, which can be set as follows:

Temperature at the top of the column a maximum of 11O ⁰ C temperature at bottom of column 40 to 80 ⁰ C. The separation of the extract and raffinate, and the recovery and recycling of the solvent can be carried out by customary methods.

If to improve the oxidation resistance a hydrocatalytic treatment is carried out, it can be carried out under the following conditions will:

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300 "until 450 2457467 ⁰ C temperature 35 "until 210 bar Pressure (gauge pressure)

Room flow initial velocity 0.1 to 5 V / V / hour ,

Hydrogen gas rate 360 to 1800 nr / nr \

Catalyst. one or more hydrogenation components from the groups
/ VIa and VIII of the periodic table on a refractory support. I.

The main goal is the removal of sulfur compounds! fertilize and other unstable compounds. The conditions should be as consistent as possible with this goal
be mild. The viscosity index is for insulating oils
and refrigeration oils are not particularly important, and the
Conditions should be chosen so that hydrogenative cracking is avoided as far as possible. The . preferred conditions for any given feedstock can be determined experimentally. j

Suitable refractory supports for the catalyst are ^; the oxides of elements of groups II, III and IV of the 'Periodic Table, each alone or in a mixture, ins-; Special aluminum oxide, silicon dioxide or their overall [mix. A preferred carrier may be 50 to 90 weight percent; Al ₉ O, and 10 to 50 percent by weight SiO ₉ . i

i The hydrogenation components used are preferably one or!

several oxides or sulfides of metals from group VIa ■ (chromium, molybdenum or tungsten) and the iron group j metals (iron, cobalt or nickel) »When using ^! of platinum group metals, these are expediently in
metallic Eorm. The hydrogenation components can be "in the following amounts, calculated in each case be used as the metal.:

Metals of group VIa '2 to 25 wt .- ^
Iron group metals 1 to 15 ".:

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Platinum group metals 0.1 "to 5 wt .- ^

Preferred hydrogenation components are 2 to 25 wt. Molybdenum (expressed as metal, but as oxide. Or
Sulphide present) and 1 to 15 weight <, - $ nickel and / or
Cobalt (again expressed as metal, but as
Oxide or sulfide present).

After the main treatment stages described above, the product can be finished-treated in a known manner
will. For example, it can be distilled and possibly clarified by percolation through bauxite or clay to remove light ends as needed
hydrofinishing or a mild acid treatment
be subjected. ;

The invention is further illustrated by the following examples
explained. |

I example 1 '. j

A vacuum gas oil from a j Iranian light crude used. The oil had the;

the following key figures: j

Beginning of boiling) determined with TBP column 257 ° C i End of boiling <and by gas-liquid-

Chromatography
Kinematic viscosity at 99 ⁰ C 2.15 oSt \

Pour point +6 ⁰ C j

The oil was catalyzed under the following conditions [

table dewaxed: j

Temperature 4O4 ° C!

Total pressure (gauge pressure) 70 bar ^;

Space flow rate 1.0 Y / V / hr.

3 3
Amount of gas with straight passage 1600 m / m

(at 20 ⁰ C and normal pressure)

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The catalyst used was platinum on a decationized mordenite with increased SiO
the key figures used:

Mordenite with an increased SiOg / AlgOj ratio and the following

0.565 Weight fo - / S I.
i 38.4 4.2 Il j O ₁ 61 Il I. 17.6: 1 420 m ⁱ

platinum

Silicon

aluminum

sodium

Si0 ₂ / Al ₂ 0 ₅ molar ratio surface

The product was boiling below 250C to remove Portions distilled and then with furfural under

extracted under the following conditions:!

Volume ratio of oil to solvent 100 i

Temperature at the foot of the column 52 ° C

Temperature at the top of the column 75 ° C

Theoretical soils. 6!

The final treatment was percolation by clay (2fo clay treatment). After the catalytic en. Dewaxed and after solvent extraction, the product had the following metrics:

Viscosity at 99 ° 0 _Λ cSt sulfur, wt .- $ pour point, ⁰ C
Composition:

⁰ A *

The oil has been tested for transformer oils according to the tests of BS 148/1972 (according to IEC class 1) and also according to the requirements of International

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Numbers: With furfural
treated
waxed oil I.
I.
i Dewaxed
oil , 2.53 un- 2.43 0.65
-48 1.87
<-57 8th '24.7 35 28 57 47

Electrotechnical Commission Glass II (IEC publication 296/1969). The regulations of IEC Class II are concerned with the pour point . particularly strict. The example shows that an oil from paraffinic crude oil prepared by the method according to the Invention has been treated that can meet the requirements of all tests.

Density, g / cnr "at. 20 C ⁰

Kinematic toughness
in cSt

Iranian IEC Specification Oil '.

0.862

at 20 ~ C 20, at -1O ⁰ C - at -30 C 762 Pour point, ⁰ C -48 Flash point, ⁰ C 154 Number of re-trails, mg KOH / g 0.01 Loss factor at 90 ⁰ C 0.15x10

<0.895

Class I Class II max 40 max 25 max 800 ■;

max.1800 max.-50 max.-45 min.140 min.130

0.03 max

- ■ ζ

max 5 x 10

Oxidation test
Mud,

- ° / o 0.07

Acidity after oxidation,

mg KOH / g '0.28

0.10 (max.) 0.40 (max.)

Example 2

The same feedstock as used in the experiment described in Example 1 was used Furfural extracted under the following conditions:

Volume ratio of solvent to oil

Extraction column:

Temperature at the bottom of the column
Temperature at the top of the column. Theoretical trays

175

55 ⁰ C 85 ⁰ C

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- 13 - j

The product was then over the same catalyst as in Example 1 under the following conditions catalytically dewaxed:

'ο i

Temperature 355 C ι

Total pressure (gauge pressure) 69 bar

Room flow velocity 1.0 V / V / hour "

- 3 "* circulation gas volume (calculated" at normal 1700 Hm / m "'

conditions, 20 ⁰ C)

Analysis of the treated with furfural "and catalytic dewaxed oil gave the following values:

Viscosity at 99 ⁰ O ₅ cSt

Sulfur content, wt. Flow point, ⁰ C Composition:

With furfural
treated 17th With furfurol be
acts and kata
lytically outgrowth 2, 33 2.43 0, +9 0.30 3 -42 5, 6.1 23 33 72 61

C p »

This 01 was then tested with regard to the important specifications for refrigeration oils, namely flock point and Freon insolubles at -4O ⁰ C. The following results were obtained:

Flock point -52 ⁰ C

Freon insolubles at -40 ⁰ C <0.01

These values cut when compared with the values for oils made from naphthenic oils be cheap.

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A Kirwaiii crude vacuum gas oil was made from among the following Conditions treated hydrocautically?

Temperature '375 C Pressure (gauge pressure) 138 bar

Room air flow speed 1.0 V / V / hour «

Hydrogen gas rate 1300 m / m

A catalyst of cobalt and molybdenum oxide Silica / alumina and the following Contents of Co, Mo and'Si (expressed as an element) had was used;

Co 1.8 wt -. ° / o

Mon 12.7 "Si 9.0"

After distillation to remove material boiling below 250 ° C, the product was used of the same catalyst as in Example 1 hydrocatalytically dewaxed under the following conditions:

Temperature 32O ⁰ C

Pressure (gauge pressure) 35 bar

Room flow velocity 1.0 V / V / hour.

3 3

Y / ass er st off gas rate ■ 900 m / m

The product was distilled to remove below 25O ⁰ C boiling material, but not subjected to treatment finished. The key figures for the feedstock, the hydrocatalytically treated oil and the dewaxed oil are given in the table below.

Table 3

mission
material Hydrocata
lytic "be
traded oil Finished
product TBP Destilla
tion (by gas
Liquid -
Chromatography) 235-438 262-431 -
258-433 ASTM boiling point
rich, ⁰ G 281-375 _ _ Viscosity "at
99 ⁰ C, cSt " 2.1 2.1 2.3 Sulfur content,
Wt .- $ 2.5 0.0003 0.0004 Pour point, ⁰ C +5 +9 <-57 composition 23 25th 38 ⁰ A 21 5 7th '56 70 55

The values in Table 3 show that the product has a composition similar to that of Example 1 manufactured specification product.

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Claims (10)

Sponsorship claims 1) Process for catalytic dewaxing for the production of insulating oils or refrigeration: machine oils, characterized in that petroleum fractions with an original pour point of j -3 ° "to +21 ⁰ O, an original sulfur content i from 0.1 "to 3 wt .- ^ and a viscosity of 1.5 j to 4 cSt at 99 ⁰ C in the presence of hydrogen with a catalyst" that brings a; crystalline mordenite having a reduced alkali metal content and · one or more, one in the _{mordenite:-made} from the hydrogenation .Groups Via I and VIII of the periodic system, into ^contact: and thereby brings the pour point of the fraction decreased and the fraction of a treatment - j raises, by at least 50 wt .- ^ sulfur 'are removed and their oxidation resistance is ER höht ■, and a product is isolated, which has a flow point of not j mEH-r than -30 ⁰ C and a viscosity j of 1.5 Ma 4 cSt at 99 ⁰ C. j 2) Method according to claim 1, characterized in that: that the catalytic dewaxing is carried out at a temperature • temperature in the range from 250 to 500 ⁰ C, a manometer ^: pressure in the range from 7 to 200 bar, a room flow, measurement speed in the range from 0.1 to 20 V / V / ■ Hours and a supplied amount of hydrogen of 90 i • ζ -ζ - carries out up to 3600 no / no input material. ! 3) Method according to claim 1 and 2, characterized in that that one uses a mordenite which has a silicon dioxide / aluminum oxide ratio of at least 14: 1. 509825/0935 4) Process according to claim 1 to 3, characterized in that a catalyst is used which
contains a platinum group metal as a hydrogenation component. · 5) Method according to claim 1 Ms 4 »characterized in that a catalyst is used which
the platinum group metal in an amount from O, O1 to
Contains 10 wt. 6) Method according to claim 1 to 5, characterized in that the treatment for the removal of; Sulfur performs solvent extraction. j 7) Method according to claim 1 to 6, characterized in that that sulfur dioxide / benzene, phenol, glycol or- j Furfural used. ! 8) The method according to claim 1 to 5, characterized gekennseichnet that is carried out as a treatment for sulfur removal \ a catalytic hydro-treatment. 9) Method according to claim 1 to 8, characterized in that the hydrocatalytic treatment at a 1 temperature in the range of 300 ° to 45O ⁰ C, a
Pressure in the range from 35 to 210 bar (gauge pressure): a space flow velocity in the range of; 0. Γ to 5 V / V / hour and a hydrogen flow-! Quantity from 360 to 1800 m ^ / m ^. input material over ^! a catalyst containing one or more hydrogenation components from groups' VIA and VIII of the
Periodic table on a refractory · contains, is carried out. ^! 10) Method according to claim 9, characterized in that
that one or more oxides are used as the hydrogenation component
and / or sulfides of a metal from group VIA and /
or an iron group metal is used; 509825/0935