DE1645812A1 - Process for the production of lubricating oils - Google Patents

Description

Texaco Development Corp. 1 3 «*%. New York, N .Y., V.St.Am. / Process for the production of lubricating oils

When extracting lubricating oils from naphtha, a fraction is separated which contains the lubricating oil components, or more of these by distillation, usually by vacuum distillation. These crude oil fractions contain naturally occurring, unstable materials, which tend to form precipitates in the plant as a result of the effects of heat and / or oxidation to have a corrosive effect on them «With paraffinic oils In addition, it is often desirable to increase the viscosity index by removing the more aromatic components with a lower viscosity index from them. To do this, you need a considerable amount of material contained in the raw stock, namely depending on the desired end product properties e.g. about 10 to 60 £, remove or even destroy. The most common way to do this is nowadays the extraction with the help of a solvent that is resistant to the more unstable molecules of mainly aromatic and non-hydrocarbon-like character is selectively effective

When treating oils to remove their unstable, corrosive and low-viscosity components the raw toc k become considerable, i.e. 10 volume-jC Excessive amounts of material withdrawn. These measures under " differs markedly from those in lubricating oil extraction used discoloration measures in which only trace amounts e.g. less than 1.0 * removed from coloring material *

POM11 / 1254. ₂ .

will. The color enhancement is usually done by Treatment with clay or mild acid, or by mild hydrogenation and often after solvent extraction * Raw stock treated only for color enhancement is usually thermal and oxidative Unsatisfactory stability or viscosity index. Crude lubricating oils are also often subjected to dewaxing, to lower the cloud point or the pour point test.

We already know N-methyl-2-pyrrolidone (abbreviated to HMP) as a solvent for the separation of olefins, diolefins and aromatic hydrocarbons and as a means for Color enhancement of Cl. But until now the fact was unknown that NMP is a powerful solvent for separation on the one hand from thermally and oxidatively inadequately stable constituents from lubricant components and on the other hand Components with a low viscosity index from lubricating oil is.

The invention is based on the production of lubricating oils successive distillation, preferably under vacuum, solvent extraction using NMP as the selective solvent, Dewaxing, addition of inhibitors and blending directed. The finished lubricating oils do not require any final treatments such as weak hydrogenation or clay or acid treatment. In the solvent refining step, the lubricating oil helps to dissolve out at least 10 volumes sufficient amount of NMP washed at a temperature which is at least 10 °, and preferably between 10 ° and

009811/1254

121 ° C, but below the point of complete miscibility of lubricating oil and NMP. The NMP amount is - on

Lubricating oil stock related - preferably between 50 and 45OJi. This gives a lubricating oil refined product with an improved viscosity index and higher thermal and oxidative stability. In the case of petroleum-based lubricating oils, all that is necessary to obtain commercial goods is to dewax the raffinate and add an inhibitor, while in the case of naphthenic lubricating oils only the addition of an inhibitor is required. Ä

Solvent extraction using NMP is suitable for petroleum-based lubricating oils, such as those used in production of crankcase lubricants, as well as for naphthenic oils, such as are used, for example, for the production of turbine lubricating oils. The viscosity index is at lubricating oil stick between about 40 and 105 units on a petroleum basis and at least 10 units higher for refined lubricating oil. Petroleu;. »Lubricating oils work with extract ion temperatures between about 49 ° and 121 ° and preferably about 60 ° and 82 ° and an NMP / oil ratio of 0.5 to 4.5: 1 and preferably 1 to 3.4: 1. Lie near naphthenic oil stocks the corresponding operating values between 10 ° and 93 ° and preferably 24 ° and 66 ° for temperature, as well as between 0.5 to 3.0: 1 and preferably 0.75 to 2.0: 1 for the NMP dosage. Noteworthy, the solvent dosage in NMP is about 5Q # below that of furfural as Widely used selective solvent.

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Solution-refined paraffin oils are typical quite paraffin-rich and, as a result, show zlemlloh high values for pour point and cloud point. In order to obtain lubricating oil with a low stook point, one must remove these paraffinic material, waa e.g. In known way can be done with the help of methyl ethyl ketone-toluene as a solvent. Aan cools for this purpose the so diluted, paraffin-containing 01 so strongly that the paraffin precipitates in the form of solid crystals, the crystals are filtered off and finally the oil is separated off from the solvent by distillation. The end product is then dewaxed, low pour point raffinate oil.

The attached figure shows in a block diagram the sequence of work steps in the production of lubricating oils according to the invention. Crude oil is fed into the crude oil distillation plant 2 via line 1 fed, in which it is in lower boiling fractions, such as gas, fuel distillates and gas oils, which are discharged via line 3, in lubricating oil distillates, which are discharged via line 5 are passed on, and is broken down into the crude oil residue, which is discharged via line 4. The lubricating oil distillate enters the solvent extraction system 6, where it passes through Wash out with NMP in the lubricating oil extract, which is discharged via line 7, and is broken down into raffinate oil, which is via Line 8 is transferred to the dewaxing plant 9 The waxes are removed in it and discharged via line 10. The raffinate oil that has been dewaxed in this way is passed through a line withdrawn, combined with the inhibitor supplied via line 12 and axially via line 13. to the mixing plant for the

Lubricating oil commercial product transferred '.

009I11 / US4. 5 -

~ ^S ~ 16A5812

example 1

In a particular embodiment of the invention, a crude oil vacuum distillate designated as wax distillate 20 with the characteristic values: 3 US viscosity ° served as the lubricating oil stick

at 27.8 ° and 56.0 at ^ 9 ⁰ C, viscosity index 73.5, refractive index 1.4820 at 70 ⁰ C and Lovibond Tintometer-Farbahl 580 (with 1/2 inch cell). It was extracted in a one-step en-Ghargenextraktionsapparat on the one hand with NMP and on the other hand in a parallel experiment with furfural as solvent. The test conditions and results are summarized in Table I below:

Table I. Versuehsbedinpunpen

Solvent furfural NMP

Solvent dosage in # 200 200

Extraction temperature in C 66 66

Raffinate oil yield in vol. ~% 85 75

Raffinate values SU3 viscosity at 57.8 ° C 317 265 SUS viscosity at 99 O C ⁰ 52.6 51 "9 Viscosity index 9 * · 0 110 · 5 Color number (with 1/2 inch cell) 50 20 Refractive index at 70 ⁰ C l. * 7O5 1 * 68θ

As can be seen, yields under the same extraction conditions NMP is a raffinate oil with significantly compared to furfural higher viscosity index

Left! 2

Example 1 was with the modification Niederholt, u & au with Q lnei 'V Ie la tuf en-Dauerbötr lebs -Extrakt Ions an was "gearb" i It et mirde, The conditions and results of the test are again tabulated below

Table II
For the viscosity index level 90

Test conditions

solvent

Solvent dosage extraction temperature, C Refined oil yield in volume -

Furfural NMP 4oo
67
73.5 150
60
78.5 353
89.5
-12.2 378
55.7
90.0
-9.4

Characteristic values of the dewaxed raffinate «_ — ___

3U3 viscosity at 37.8 ⁰ C SÜS-Viskosltät 99.0 C Viscosity Index Pour Point in C

Lovibond color number (with 1/2 inch cell) 45 40

For the viscosity3 index level 100 test conditions
Solvent · Furfural NMP

Solvent Dosing, VoI - £ 66Ο 202

Extraction temperature, C 85 60

Raf finato oil yield in vol. -G 59 * 7 72.7

Characteristic values of the dewaxed raffinate

Specific weight in ⁰ API _Λ 29 * 5 29.4

SÜS viscosity at 37.8 ° C 3Oo 252

SUS viscosity at 99.0 ⁰ C 53 * 0 * 9 # 8

Viscosity index 100.0 100.0

Pour point In ⁰ C -12.2 -15 * 0

Also in this Dauerbetriebsνersuch custody shows the strong superiority of MMP versus furfural, a given viscosity 'index of Raff indee inatöls with him in much lower doses and will be achieved, "it higher at lower extraction temperature, and on top of that,

Beis pie l ^ »-

Green vacuum deetillate fractone labeled 300 Pale Stock

oomi / t * s * ^ ⁷ "

ORiGiNAL INSPECTED

from naphthenisehem crude oil was specified in Table III conditions with MMP treated · The characteristic values of input oil Raffinate1 and extract are shown in Table IV 2USanmengesteilt. Table III

Operating conditions

Solvent dosage in Vol · - ^

Extract outlet temperature in G Raffinate outlet temperature in C

Raffinate oil yield in % by volume 81.6

Table IV '

Characteristic values of input oil, raffinates! and extract

Input"! Raffinate oil extract

Specific weight in ⁰ API 20.6 23.8 '

C OC flash point in ⁹ C 204 191

South viscosity at 37.8 ° C 436 338

SUS viscosity at 99.0 C 50.2 48.2 73.6

Pour point in ° c - 28.9 -31.6 - 3.9

Ash in wt .-> 5 0.001 0.001

C-Rücl: stood in aew.-ji 0.03 0.04

j, 3,

Neutralization number 0.02 0.02

Aniline point in ° C. 76 87

Basic Np * PPm 179

Sulfur in ^ wt .- ^ 0.21 0.13 0.58

Lovibond color value

at the beginning (I5 cra cell) 3 ^ 5 95

after 24 hours (with 6 tariff

Toe) at 99 ° - 160

after 24 hours (with 1/2 inch cell) at 99 - 95 .- ■ - ■■ Lovibond color stability
(1.25 cm cell) at 204 °>

at the beginning of 80 15

after 1 hour . I65 * 5

after 2 hours 260 90

Refractive index at 70 ⁰ O 1.495 * 1, Λ8θ5 1.5617

SOD lead corrosion test
163 C change in weight

big / square inch after 1 hr. SJs "^ # 0

mg / square inch at 6 hours, -48.6 -18.8

Toettcher paint test, I3 hours at

177 ⁰ C

Lacquer, 184 mg 21.0

Increase in viscosity at 99 C in # 100 110

Neutralization number 6.8 9.4

Heat test, 125 hours at 204 ° C

Loss of evaporation in # - 4.0

Viability increase CS at 99 ° '

in Jf 73.5 46Λ

Neutralization number 0.95 1.5

Mud ■ · none none

The S OD-BIe ikorros ions teat Ut In the Military Code

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MEL-L-708 C for lubricating oil, aircraft turbo-oil on a synthetic basis from November 2, 1955 and in the American Patent specification j5 003 963 described in detail.

The Toettcher paint test is in the American patent 2 67 ^ 577 described.

In the heat test 250 ml oil sample to be 125 hours, heated to 121 ⁰ C and then kept for one day at room temperature. The specified characteristic values are then determined.

This example shows that Raffinate oil compared to the input oil has significantly more favorable characteristics regarding color, color stability, corrosiveness and Has heat resistance.

Example 4

The wax distillate used in Example 1 20 input oil W was rait NMP in the NMP oil ratio 1.5 ι 1 at an outlet temperature of 6 $ ° G for the extract and 99 ° for the raffinate oil extracted , which in a yield of 68.6 volume- ^ was incurred. The characteristic values of Singabeöl, _f raffinate and extract are zuaamnwtngesteilt in Table V "

(see page 9)

- 9-

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⁰ C - 9 - 184; 1812 ' 66, O ° 0
99.0 ° C Table V Äuagan ^ söl Raffinatgl extract Specific weight ,, ⁰ APX
COS flash point in 25.3.
232 30.0
■ 246-. 243 SUS viscosity at
SUS viscosity at
SUS viscosity at 437
57.0 280 '
approx
51.6 424
100.4 Viscosity index
Pour point in C 78.5
. 38 "■. 100.5
41: 32

Lovibond color value
at the beginning (with 1/2 inch cell)

at the beginning (with 6 inch cell) -. '■ I5

after 24 hours at lo4 ° C

(1/2 inch cell) 28o -. ■■ - _Λ

after 24 hours at 104 ° C

'^ Inch cell) «. -35 -

C residue in weight yg 0.10 0.006 -

Ash in wt .- ^ O ₅ OOl 0.001

Neutralization number 0. 4o 0.03 -

Sulfur in Qew .- ^ 0 »22 0.07. 0.58

Basic N ₀ , ppm 34- - -

Refractive index at 70 ⁰ C · l _# 48o5 1.4630 1.5189

Input oil and raffinate oil were then added to one Pour point of -15 ° C dewaxed and again on their Investigated characteristic values which are summarized in Table VI

(see page 10)

- 10 -

0098117-1254:

Wl

tUö - V ASloSiSA i5äMj - IQKäJ. Jl I 3% J% e & VO ⁰³ V Acs £ 013 © Α l! J C £! / | £ On ^ ώ ^ y 37 a ^ J w

■? F4 θ Viii © "3 i'Mi'sipSifSsi = !?

Äsoh © iss

Sulfur in GeW ₀ ^

Lovibond Parb value
(with 1/2 inch cell)
initially

after 24 hours

Lovibond color stability at 2O4 ° C (with 1/2 inch cell) initially

after 1 hour after 2 hours *

SÖD lead corrosion test at .163 ⁰ C (1)
Weight change
mg / square inch after 1 hour mg / square inch after -6 hours

Spindle oil oxidation test, 24 hours at 121 ° C (2) Saponification number
Neutralization number
Viscosity increase at 37.8 ⁰ C in %

Heat test, 125 hours at 204 ⁶ C (3)

Evaporation loss in % viscosity increase
CS at 99 ° C in %
SUS at 99 ° C in %
Neutralization number
mud

deparaffInlettes 01

6t-61, B

- no ©

0 * 10

0.55 0.23

2.8 0.7 *

12.6

0.8

35.9 23.6 1.6 none

-15 none

20 30:

40.4 248

0.38 11.3

1.3

22.0 11.2 1.2 none

SGD anti-corrosion test and heat test were carried out according to the in Table IV performed procedures.

With the spindle oil-CKydationsteet, the oil to be tested is eaten Presence of steel, copper and lead tires 24 hours

009811 / 12-54- - 11 -

long while blowing air through to 121 ° C heated and then on viscosity increase «or saponification» and neutralization values examined.

As the results of this example show, NMP are refined oils compared to the unrefined Input oils are lighter in color and show improved characteristics for color »corrosiveness and warning resistance.

Example 5 · '"""" ./. - _f ': ■ - - -'_ -

In this example, the MHP was compared with another γ- butyrolaetam, namely the unsubstituted 2-PyTrQlIdOn ₁₁ , with regard to its effectiveness for refining lubricants by means of KjsungsmittFiI-Extraktlon. For this purpose, on the one hand, a low-viscosity and, on the other hand, a medium-viscosity input lubricating oil were treated under the same extraction conditions with NMP or 2-pyrrolidone. It was found that NMP is far superior in terms of viscosity index improvement in that it contains three times more extracts under the same temperature and dosage conditions! than 2-pyrrolidone ₍ able to remove below. NMP also provides a raffinate oil with a more strongly reduced refractive index, whereby the reduction is greater with medium-viscosity input oil than with low-viscosity oil. "· -..-

"0008 11/1254

Claims (5)

ι j mm around Texaco Development Corp,
New York, NY, = V.St.Am. Claims experienced for obtaining a lubricating oil, characterized in that a lubricating oil stick with a solvent of N-methyl-2-pyrrolidone at a temperature which is at least 10 ⁰ C and under the point of complete miscibility of lubricating oil and N-methyl-2-pyrrolidone is, in such a dosage brings into contact> that at least 10 percent by volume of material is dissolved by the Sehmierölstook. 2) Method according to claim 1, characterized in that the dosage is kept between about 50 and 45Q ^. »Method according to claim 1 or 2, characterized in that that the contact temperature is between 10 ° and 121 ° C holds, W 4) Method according to one of the preceding claims, characterized in that a crude oil is vacuum distilled, a vacuum distillate is separated off, and this is brought into contact with the solvent 5) Method according to one of the preceding claims, characterized in that the Baffinatöl so far dewaxed as it is used to achieve a round oil ni with a lowered pour point is required, and this Basic oil with eteefli inhibitor in order to create a 00P811 / 1254