DE2121458A1 - Tar treatment process - Google Patents

Description

Tar treatment process

The invention relates to a method for processing 'I'eer in the heat to oil, gas and rech.

Generally tar produced by dry distillation coal or the splitting of crude oil or petroleum constituents originates, basically heat-treated for the extraction of oils, where pitch is created as a by-product »In the industry is the tar usually a distillation under atmospheric or reduced pressure to achieve light, medium and heavy fractions for industrial uses, and any remaining residue is classified as pitch won »This pitch is used as a binder for the manufacture of electrodes, as an impregnating agent for fired

76- (OGtf-15) JJo-He (6)

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Electrodes for Veroesseranj egg mechanical and electrical Properties of the same as an additive without coking. of coal to produce coke with improved properties uses ο that generated in the manner mentioned © However, bad luck has only moderate or limited Iigen3cr. & I'ten, so that it can only be used in limited terms and for specific purposes is ο

As cnarakteristische property of the pitch -.vira generally given its solubility in various solvents: General v; ith comprising a pitch and a benzollöslicher benzolunlöslicner proportion discriminated v divided many Yieiter latter in a chinolinlöslxchen and a cninciinunlösuchen portion; IRAE _o After herkömmlicher- method Received pitch has i: ~ in general an expansion iur. :, 3 van & t over 60 ⁰ G and contains 20 ois 40 j-e '/;, -'; ■ & benzcliinlcslior.e proportions and 5 ois 20 je7 / _s - > ö quinoline-contaminated proportions,

Dine increase in benzene content · ,, -. Is usually leads inevitably to an increase in the proportion oninoiinunlöslichen ".Venn tried, however, to reduce the quinoline share, including the share falls below oenzolunlösliche increase in benzollösliehen" Eils ₀ i ^ r many cases However, the!,! narrow proportions of benzene-insoluble and quinoline-insoluble part as well as the difference between the two are stinking for the properties of the pitch and its successful use

For example, Elsistroden with improved properties in terms of strength, density and specificity electrical resistance using pitch are to be produced as a binding agent, it is necessary to

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that the pitch contains at least 80% by weight of benzene-insoluble parts and a mineral content. 'Jen & lt in ci.inoiinunle are looking for shares una da- · ais i' for the uiff er en ξ between benzoiunlcslicheii: una quinoline-insoluble share responsible com-! - • cneiite (sojo p> -HaX ¹ Z) at least 2v jcv; , - ;. _o represents a pitch which satisfies such requirements, is now difficult to obtain because an attempt to increase the "ceiizclunlösuchen proportion au: more 2I3; 'O ie. ^{1" 1} "- i commonly to a corresponding .Äinar.i. :: e of the cninoline-insoluble portion leads.

'.. "e'iter it is desirable because i pitch which ver./e::uoc as impregnating agents for burned electrodes, - is, verden, a ^iac>,% lit: hst low cnindlnunlcslichen share oesitzt" teaching in For one thing, it is necessary that the i-eoh for this purpose jiic:; t t- or more than 'j -j-ev / o - / - quinoiin-insoluble parts but at least 20 ü-ewo-f-benzolunlcsliohe parts exist in the conventional process Now, however - "-" Ie difficulty, that the production of peer, with not mex: r as 2 Gev, - _e -> - o are looking for shares to be "": c_- unlcsliclien share of about 15 uew _e - > oaer less ¹ leads to a predominant '.,. close to bensollcsiich-s ^ AatvU, vfas it

makes it impossible to achieve bad luck, as that for an impregnating agent possesses desirable properties. The properties of a pitch obtained by conventional methods are therefore subject to a limitation, and it was previously impossible to control aiese so that :? one for vera-i.ieiene uses and purposes desired combination was obtained,

The aim of the invention is therefore a method, naoh that a pitch useful for a wide variety of applications can be obtained in high yield by treating 2eer can, in which in particular the benzene-insoluble and cninolin-

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SAOOfHQiNAL

insoluble fractions can be adjusted independently of one another, so that one is able to produce a pitch that meets the requirements of the most varied of uses and purposes »The aim is to avoid coking difficulties and to obtain oils of high quality that are almost free of unstable components ₀ in principle, the treatment of tar according to the invention at an elevated pressure compared to the conventional treatment and distillation in at least two stages, each stage valuable intermediates are obtained, aie gfs "can be combined ₀

More specifically, the "method for treating tar according to the invention is characterized in that one

1) the tar is heated in a first stage to a temperature of 320 to 470 ⁰ O under an excess pressure of 1 to 20 kg / cm to generate gas, oil and pitch;

2) that one then oil and pitch for the production of pitch having a softening point of at least 6O ⁰ C and a content of 20 to 45 wt -fö of benzene units and 3 to 20 SeWo -. '/ Ä to chinolinunlösuchen proportions by distillation separates }

3) that the resulting oil in at least a second Stage under an overpressure of 3 to 35 kg / cm to a temperature in the range of 370 to 54O ° O, which is at least 10 ° 0 above the heating temperature of the previous stage is to be. generation of gas, oil and pitch heats; and

4) pitch, and oil for the production of pitch having a softening point of at least 60 ⁰ C and a content of 15 to 40 $ Gewr- to benzene units and not as a 2 wt .- $ of ohinolinunlösuchen proportions by distillation separates more from each other.

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Can be prepared by this method a multi-stage heat treatment pitch may in each otufe having valuable properties obtained v / ground, which differ from one another, so that by the resulting in the individual stages pitch locations uisehen new products obtained = Thereby, the pitch yield at least 75 wt _o - $ > Achieve (based on the tar) without coking difficulties and finally thermally stable oils with excellent properties and gases that can be used as fuel can be obtained as by-products

The softening point is used in the context of this description as well as the claims a v / ert denotes that according to the "mercury method" is determined according to JIS (Japanese Industrial Standards) K 2421 -66 «,

The pressure specifications "kg / cm" in the context of this description as well as the claims mean measured or overpressure (kg / cm gauge).

According to the invention, tar is subjected to a two-stage heat treatment under increased pressure, as a result of which pitch with special properties is obtained in each heat treatment stage. More specifically, when tar is heated to 320 to 47O ⁰ O under increased pressure from 1 to 20 kg / cm pitch with 20 to 45 Gewe- ^ benzene-insoluble portion and 3 to 20 wt "-> quinoline-insoluble portion in high yield together with uas and oil can be obtained. A pitch with such properties fully meets the requirements for a variety of uses and can be used as a binder for electrodes, as an impregnating agent for burned electrodes, and as an additive for carbon. Although the increase in the benzene

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insoluble fraction leads to an increase in the quinoline insolubility This increase is much smaller than with the conventional procedure, even if the benzene-insoluble If the proportion exceeds 30- & ew »- '«, you can at least 23 Grewe- $ of the p-resin component are retained, which is special The advantage of the pitch as a binder for the production of electrodes with more excellent properties can be used as conventionally possible,

If that is pitch that was produced according to the invention and one ^! 1 resin level 23 percent ₀ - containing o, is used as the binder, the electrodes produced have an improved flexural strength, compressive strength and an improved electrical resistivity ,, The Satsache that pitch may be obtained with such characteristics is solely of the preceding Ascribed to heat treatment carried out under increased pressure, 30 that active components in the lake are positively converted into pitch »Such a result cannot be achieved by conventional distillation methods in which the heat treatment is carried out under atmospheric or reduced pressure»

According to the invention, the oil resulting in the 1st stage of the heat treatment is then processed under more severe conditions treated as in the 1st stage, whereby pitch with a very low quinoline-insoluble content is produced. Despite the The fact that the obtained in the 2 "stage of heat treatment Pitch contains 15 to 40 percent by weight - ^ benzene-insoluble parts, the amount of quinoline-insoluble components is even lower than 2 Ssw .- / yo Such a pitch is extremely suitable for applications in which a sufficiently large amount is available quinoline-insoluble fraction are essential, as in

for burnt electrodes "

A fired electrode impregnated with a pitch with a low ehinoline-insoluble fraction according to the invention has an extraordinarily improved flexural strength and compressive strength, as well as an excellent specific electrical resistance ₀ otufe of 7 / ärmebehandlung obtained in terms of its properties, in particular as regards the quinoline-insoluble fraction is different, both pitch locations can be a pitch are formed with specially desired properties by mixing together. The products according to the invention tons so because of their excellent properties in the wider iiaße the respective Uses- and uses to be adapted "

Moreover, since the light originating from the 1 "stage of the heat treatment oil is converted in the 2nd stage in Pech addition, the total yield can be substantially increased in pitch, and the resulting only in the 2 ₀ Wärmebehandlirngsstufe oil product is virtually free of unstable components ,, In this way, a high-quality oil, which is very useful as an absorbent, is produced. According to the invention, after tar is converted into pitch by (at least) 2-stage heat treatment, it is possible to remove unstable components in the course of the 1st stage of the To convert heat treatment into pitch, so that coking or malfunctions with regard to the operation or in the apparatus hardly occur, even if the products are treated under more severe conditions during the second heat treatment stage.

The softening point of the in each heat treatment stage

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obtained pitch can be over a wide range as desired
by varying the heat treatment conditions as well
the conditions for the distillation carried out after the heat treatment can be set by varying the amount of low-boiling fraction. In general, the softening point of pitch is in the range from about 60 to 150 ⁰ G,
although it is possible to use higher softening point pitch
to get from 150 to 300 ⁰ O »

The tars to be used as the starting material according to the invention include coal tar and oil tar obtained by thermal or catalytic cracking of petroleum »die
Tars have an absolute viscosity of 20 to 1,000 Gentipoise at 50 ° C and contain 5 to 30 parts by weight - & a fraction boiling from over 270 ° 0 and 25 to 45% by weight - ^ a fraction from 0-36O ⁰ O
boiling faction. Particularly preferred are i'eere with an absolute viscosity of 50 to 200 Gentipoise at 50 ⁰ C and
with a content of 15 to 25 wt _o - ^ o one of 0-27O ⁰ C boiling fraction and from 30 to 40 percent by _e -> one of 0-36O ⁰ C boiling fraction,

liach the method according to the invention, the starting tar is raised under an increased pressure of 1 to 20 kg / cm
320 to 470 "G heated, whereby the active components contained in the starting tar are positively converted into pitch.
More specifically suffer heavy fractions and relatively low
boiling unstable condensed ring compounds condensation polymerizations and are thus converted into pitch,
while unreacted components are obtained as an oil fraction besides a gaseous reaction product.

During this stage the reaction temperature is from

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320-470 ⁰ C of significant importance: At a temperature below 320 ⁰ G no sufficient reaction is obtained, while a temperature above 470 ° ΰ gives rise to coke in the reactor?. The reaction can be preferably carried out at a! Temperature 330-430 ⁰ G ,,

It is necessary that the conversion of this stage takes place under increased pressure of 1 to 20 kg / cm, so that the substances to be converted in the tar can be retained in the liquid phase, which ensures a positive conversion to pitch. that treatment under atmospheric or reduced pressure is avoided because it would allow relatively low-boiling, unstable condensed hanging compounds to remain unreacted and not to undergo condensation polymerization to convert to pitch, which not only prevents the formation of good quality pitch, Instead, during the 2nd heat treatment stage, which is carried out under more stringent reaction conditions, it would cause coking inside the reactor. If, on the other hand, the pressure exceeds 20 kg / cm, better results are achieved, but there are difficulties with regard to the apparatus and the Operation accepted. A suitable pressure for the reaction in this stage is therefore in particular in the range from 5 to 15 kg / cm _a. The reaction time can vary over a wide range depending on the reaction conditions and the properties of the pitch to be achieved; finished within 20 hours.

The 1st heat treatment stage leads to the production of gas, oil and pitch. The gas is used in combustion

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- ίο -

sources of material removed from the system and the resulting The mixture of oil and pitch is used to separate a distillation subject. The peen obtained in this way has a softening pump of at least 60 G and contains 20 to 45 parts by weight insoluble in benzene and 3 to 20 parts by weight of quinoline insoluble Shares o

In the Wärmebehandlunssstufe obtained oil "!", In the following 2 v / ärmeb MMA lungs stage further heated, wherein a reaction is carried out at a [temperature at least 10 ⁰ C higher than aie in the 1 "otufe temperature employed. In In this 2 »3 stage, components that were not converted in the previous hardening treatment are positively converted to pitch. The reaction temperature is in the range from 370 to 54O ⁰ U, while the reaction pressure is 3 to 35 kg / cm _β Sine reaction temperature, which would be lower as ifärmebehandlungsstufe in the 1 'or would be less than 37o ⁰ G,' the reaction would be delayed to Unuvandlung in pitch and make to achieve the desired pitch difficult, while a temperature above 540 ⁰ G occasion were coking ₀ the Reaktionsteaperatur may preferably be in the range of 420 to 46 ° G, that is, 30 to 60 ⁰ O higher than the _{temperature used in the 1 O} heat treatment stage,

Furthermore, a heating pressure below 3 kg / cm would cause evaporation of low-boiling components and thus a deterioration in the pitch yield with disadvantageous effects on the properties condition, or difficulties in operation result _f without any improvement in the efficiency he goal'ir

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The pressure can be 7 and 20 kg / cm as a precaution Implementation of the 2 “./ärmebehanüiungastui'e is in general Completed in 1 to 40 hours, although the duration of the reaction depends on the reaction conditions and the three stages of the pitch to be produced vary over a wide range canoe ο

iei the second heat treatment step v / ground jas obtained oil and pitch, and the Uas 7 formed during the reaction / ird for use in fuel sources from the systen removed Ι} -'- resulting kischung ^ ron oil and pitch wira to ^ distilled j-ennung "the pitch obtained in this step has a softening point of at least 60 ⁰ G and valuable properties in the './eise that 15 to 40 wt .- ^ benzene-insoluble components and an extremely low Llenge not more d.ho contains as 2% by weight quinoline-insoluble fractions. It is impossible by conventional processes to produce such a pitch which contains very small proportions of quinoline-insoluble proportions in spite of high proportions of benzene-soluble proportions, the amounts of which are 15 to 40 percent by weight. The pitch produced in this way has many uses, for example as an impregnating agent for burned electrodes. The present invention also has the particular advantage that the pitch obtained in the 2nd heat treatment stage can be mixed with the pitch produced in the 1st stage for convenient production of pitch having desired properties. The GI obtained by the method of the present invention has excellent heat resistance and is used as a good absorbent because unstable components are converted into pitch by the 2-step Yifarme treatment.

The invention has been described above with reference to the Pail

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21214G8

described, in which tar is processed by a 2-stage heat treatment. According to the present invention, however, the tar can also be processed by means of a multi-stage heat treatment. " The Oi obtained in the 2% heat treatment stage is then processed under more stringent conditions, for example at a temperature in the range from 380 to 56O ⁰ O, which is at least 10 ⁰ G above the temperature of the 2% treatment stage and under a pressure of 3 Heat-Treated to 35 kg / cm The pitch produced by such a multi-stage heat treatment has valuable properties and contains much smaller amounts of quinoline-insoluble components. Such a multi-stage heat treatment is expediently provided depending on the requirements of the intended application of the pitch.

The inventive method can be batchwise or continuously executed.

The following are examples to explain the invention »The The percentages given therein relate to weight.

example 1

Raw coal tar was sent to remove the water contained therein by a falling film distillation tower at 84 ⁰ G »The dried tar had an absolute viscosity at 5O ⁰ G of 102.4 cps and contained 17.1 f> one at 0-270 ⁰ G boiling fraction and $ 36.8 of a fraction boiling at 0 to 360 ⁰ O. " The tar was placed in an autoclave with a partial condenser and a pressure regulator and heated ^{to 400 ° C. under 9 kg / cm 2 for 5 hours.} The generated steam was condensed in the partial condenser and

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returned as reflux, and the uncondensed gas The tar so treated was removed from the system to separate pitch and oil to isothermal distillation with discontinuous pressure drop (flash distillation) «

The yields of pitch, oil and gas thus obtained, as well as the properties of the pitch, are given in Table I «,

The oil obtained in the 1 _O heat treatment step was then placed in an autoclave with a partial condenser and a pressure regulator ₀ In the autoclave, the oil was 10 hours under 12 kg / cm heated to 45O ⁰ G The vapor generated was condensed in the partial condenser and returned as reflux and uncondensed gas was removed from the system. The oil thus treated was subjected to isothermal distillation with intermittent pressure drop to separate pitch and oil.

The yields of pitch, oil and gas obtained and the properties of the pitch and oil are shown in Table 1.

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yield

Properties

Taoelle 1 first warmth
treatment
step second 7 / poor
treatment
step 64.0 45.5 Pech (fo) 35.1 52.4 Oil (9t) 0.9 2.1 Gas ■ (£) 80.5 81.0 Softening
Point
( ⁰ C) 45.8 46.9 fleeting
material 7.2 0.7 ohinolinun-
Lö viewfinder
Proportion of 32.0 28.7 benzene
1Ö viewfinder
proportion of - 1.05 specific
weight - 221 Temp »for
20 ^ -Des-bil-
lation
( ⁰ O

for

lation

'Jemp. for

80 ^ -style-

lation

Ac enaphthene geiialt

252

336 spores

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Example 2

Dried sole tar of the same kind as in Example 1 was heat-treated under the same conditions as in Example 1, and the oil obtained in the 2nd heat treatment step was then placed in an autoclave with a partial condenser and a pressure regulator and subjected to a pressure of 20 kg / cm for 20 hours heated to 46O ^{0 G.} The product treated in this way was subjected to a distillation with a discontinuous pressure drop to separate the pitch and oil. The pitch yield based on the weight of the oil of the 2nd stage was 36.55 "} its properties are shown in Table 2 below".

Table 2

Softening Point ( ⁰ G) 82

quinoline insol finder

Proportion (Jb) 0.2

benzene-insoluble

Share (} £) o, 2

Example 3

Dried coal tar as in Example 1 was in the heat-treated in the same way as in Example 1, except that the conditions of the 1st and 2nd heat treatment stages are changed were, as indicated in Table 3 below, in which the properties of the in the respective stages Pitch and oil obtained are indicated o

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Own 'Bad luck Table 3 first warmth second V / poor sheep treatment s- treatment ten < step step 360 430 Γ Temp- ( ⁰ O) 5 8th Be J pressure ρ condition j (kg / cm G) 18th 20th gene [Duration (hours) 55.1 61.1 Γ bad luck (<? O) 44.6 37.2 Oil (ji) 0.3 1.7 the end
prey * [Gas (° / ό) 'Softening 76.0 70.5 Point
( ⁰ O) fleeting 48.2 47.3 material ($) quinoline insoluble (? -) 8.4 1.6 share benzene insoluble (fo) 35.2 28.1 share 'specific - 1.04 weight Temp, for 217 20 ^ -Destil- lation ( ⁰ O) Temp, for - 248 50 ^ -Destil- lation (OC) Tempβ for - 330 80? B-Destil- lation ( ⁰ G) Acenaph - Tracks ■ then salary (SÄ)

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Example 4

Dried coal tar of the same kind as in Example 1 was heat-treated in the same manner as described in Example 1 except that the conditions used in the _1e and 2 _O stages of the heat treatment were changed as shown in Table 4 below, in the properties of the pitch and oil obtained in the respective stages are also listed-

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- 1ö -

Conditions

yield

Property
th

bad luck

oil

Table 4 first warmth
treatment3-
atufe - ZY / eite V / 'poor
treatment3-
step 460 - 490 'Temp »( ⁰ O) 20th - 20th Pressure "
(kg / cm ^ i) 2 - 2 . Duration (hours) 71.2 40.6 Bad luck (^) 26.0 57.0 Oil bi) 2.8 2.4 Grass (fo) ■ 85.3 84.5 Softening
point (oc) 44.3 49.0 fleeting
Material (? ») quinoline insoluble
licher portion (^) 10.5 0.1 benzene-insoluble
cher portion (f>) 36.1 20.3 specific
weight 1.08 Temp »for
20 ^ -Destil-
lation ( ⁰ C) 231 3? Emp _o for
lation ( ⁰ G) 250 · lemp. for
80 ^ -Destil-
lation ( ⁰ C) 334 Acenaphthene
salary traces

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Example 5

Crude oil gas tar was dried in the same manner as in Example 1, and dried tar having an absolute viscosity at 50 ⁰ O of 28.7 cps and a content of 20.5 $ of a ^{fraction boiling at 0 to 270 0} O and 35.0 $ a fraction boiling at 0 to 360 ⁰ U is obtained. The dried tar was then subjected to the same heat treatment as in Example 1, except that the conditions used in the 1st and 2nd heat treatment stages were changed, as shown in Table 5 , which also shows the properties of the in the individual stages obtained pitch and oil are indicated.

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ttngm Table 5 first warmth
treatment
step <; 'Bad luck (</ £) 59.3
oil (? έ) 39.6
Gas (>) 0.7 Z7i? Eite Y / poor
treatment
step gene Γ Temp. ( ⁰ O) 385 'Softening ₇ q "
point ( ⁰ G) ^y> 450 the end
prey ι- J ^ g% _m 2 _G) 9 < fleeting . " ρ
Material (/ 'ο) ^ -' »^
quinolinunlö su
cher share (<jh) 8.4 9 I duration (ötd) 5 benzene-insoluble
cher portion (fo) 34.2
'specific
weight 10 'bad luck Temp, for
2O '/ 0-Distil-
lation ( ⁰ G) 48.6
48.0
3.4 < Temp. For
50 ^ o-Destil-
lation ( ⁰ O) 76.0 Temp »for
80 ^ -Destil-
Iation ( ⁰ G) 48.0
2.0 oil Acenaph
theng ^ ehalt 31.3
1.04 Own
sheep
ten ^< 216 247 340 traces

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For comparison purposes, [Deer in the following v / ei

sen treats:

Comparative example I.

Coal tar of the same kind as in Example 1 was ^{distilled under atmospheric pressure at 31O 0} O and the residue was further distilled at 345 ⁰ O under reduced pressure of -0.85 kg / cm (H2 Torr). In this way, pitch and oil were in Yields of 54.9 / ° and 45.1 ^ obtained (based on the weight of the starting coal tar used) “The properties of pitch and oil are shown in Table 6 below”.

bad luck

Table 6

Softening point ( ⁰ O) volatile material (;

quinoline insolubles substance (fi)

benzene-insoluble substance (° / ό)

67.7 50.7

4.1 18.2

specific weight

Tempο for
20 ^ -Des-Lillation (° 0)

j temp, for

* 50 ^ distillation ( ⁰ O)

Temp, for
80 ^ distillation (v3)

Acenaphthengeha.Vi

1, 08 240, 5 325 360

0,? 0

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Comparative Example II

Peen v / urae obtained according to Comparative Example I heated to 400 "ΰ under atmospheric pressure for 5 hours, The properties of the pitch obtained in this way are shown in Table 7 below.

Table 7

Softening Point ( ⁰ O) 82

quinoline-insoluble _{17 1} . Proportion of (#) "''

benzene-insoluble -yt q portion (^) '

Comparative example III

This is done by distillation under reduced pressure Comparative Example I obtained oil with the following properties was a heat treatment under the same conditions as in the 2. 7 / heat treatment stage of Example 1 was subjected to this treatment a coking with the formation of brittle solids with 82.0 $ of quinoline-insolubles in a yield of 15% based on the weight of the oil used.

The properties of the oil used were as follows:

absolute viscosity 5.8 cps at 8O ⁰ G content of 0 to

ttenaxi / an υ dxs _{n o} j 270 ⁰ G Fraction '°

Content of O to
36O ⁰ G parliamentary group

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Claims (4)

- 23 patent claims Process for processing tar in the · 7färme to oil, gas and pitch, characterized in that one 1) the tar in a first stage aux a temperature of 320 470 ois ⁰ G under an excess pressure of 1 to 20 kg / cm heats to ür3eugun £ of gas, oil and pitch; 2) that oil and pitch are then used to obtain pitch with a softening point of at least. 6O ⁰ C and Einein content of 20 to 45 Gewe-> i of benzene units and 3 to 20 wt .- '/' to chinolinunlösuchen proportions by distillation separates} 3) that the resulting oil in at least a second stage under an overpressure of 3 to 35 kc / cm ^ to a temperature in: range from 370 to 54O ° J, which is at least 10 ⁰ G above the heating temperature of the previous stage, heats up for the production of gas, oil and pitch; and 4) Pitch and oil for the production of pitch with a softening point of at least 60 ⁰ G and a content of 15 to 40 wt. 2, method according to claim 1, characterized in that the starting ^{tar has an absolute viscosity at 50 0} C of 20 to 1,000 cps and 5 to 30 wt .-? » a ⁰ to 270 G boiling PraKtion of 0 and 25 to 45 wt. -fi contains one to 36O ⁰ G-boiling fraction of 0. 109850/1584 3o method according to claim 2, characterized in that the tar has an absolute viscosity at 50 ⁰ G of 50 to 200 cps and 15 to 25 GeWo - '/ o a ^{fraction boiling from 0 to 270 0} G and 30 to 40 wt. ^ contains a fraction boiling from 0 to 360 ⁰ G «, 4o method according to claim 1, characterized in that the Y / MMA ärmeb the first stage of development at the exit Steer and at a temperature of 380 to 43o ⁰ G under increased pressure from 5 to 15 kg / cm. 5. The method according to claim 1, characterized in that the heat treatment of the second stage with the oil coming from the consoling heat treatment stage at a temperature of 420 to 460 ⁰ G under an overpressure of 7 to 20 kg / cm is carried out o 6 _O method according to claim 5, characterized in that the temperature of the second heat treatment stage is 30 to 6O ⁰ G higher than the temperature used in the first / heat treatment stage » 7o method according to claim 1, aaaurch characterized in that pitch obtained in the first heat treatment stage with I-ech from the second 7 / a.nnebehandlungsstuie under Jinstellung the Properties of the Liischpech produced in this way mixed together will ο 8 _{0 The} method according to claim 1, characterized in that the oil obtained in the second heat treatment stage before a further heat treatment under an 'overpressure. 3 to 35 kg / cm at a temperature in the range from 380 to 560 G, which is at least 10 ⁰ G above the heating temperature of the second heat treatment stage, is subjected. 109850/1 584