DE1909840A1 - Process for processing heavy fuel - Google Patents

Description

Esso Research and Engineering (US 710 ?, & 9 = ■ prio 4 «, 3ol968 Company _6o48)

P.Oo Box 55

Linden, WJ, 07036 / V.3t _o Ä _B Hamburg, Sl ₀ February 1969

Process for the processing of advertising spirit

In the production of ethylene and other olefins from one of gaseous hydrocarbons! Up to heavy oils like gas oil and crude oil, there are primarily maximum quantities after the steam cracking process obtained in ethylene and propylene; however, depending on the input material and the working conditions, liquids fall Products including a raw * steam cracked one Sohwerbenzlns and pyrolysis gasoline to * as it is in "Hydrocarbon Processing ", Vol. 44, pp. 203-208 {1965). Furthermore, with the Bsmpfcracking process in the Production of acetylene and / or ethylene also shares of steam-cracked heavy gasoline; see "Hydrocarbon Processing" Vol. 44, pp. 165, 166 (1965).

If liquid petroleum fractions and especially a heavy oil such as gas oil or crude oil, are used »so are the liquid cracking fractions extremely unstable. Because of the market demand for steam " cracked by-products, namely propylene, stable steam cracked gasoline usd aromatics like benzene, toluene and xylene, heavier feedstocks were therefore used in the refineries

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The liquid produced during the pot roasting of heavy oils However, the end product is contaminated with olefins, dolefins, oils and sulfur compounds. These impurities are usually removed through various post-treatments. ferrite, for example by repeated distillation «by hot leaching, by treatment with clay or other chemicals, by hydrofining or solvent »extraction» All of these processes are costly, cumbersome and impair economic production of motor fuels and aromatic hydrocarbons,

The purpose of the present invention is to provide a new method for processing unstable, steam-cracked To propose fractions «which require a minimum of treatment steps and which are carried out in this way can be »that the production of gasoline, of benzene / Toluene / xylene fractions, the so-called BKC fractiones ^ or an Benzene alone is increased "

According to the invention, this is achieved by an unstable, steam-cracked crude fraction without pretreatment in a first hydrogenation stage in the presence of a nickel and Tungsten-containing supported catalyst hydrogenated, whereupon the partially hydrogenated liquid fraction completely or partly in a second hydrogenation stage under more severe conditions than before in the presence of a conventional one Hydrofinler, such as sulphidated cobalt glybdate » is hydrogenated. Subsequent to the second hydrogenation stage, the product is processed depending on the desired end products further treated. When ordinary engine gasoline produces » a simple distillation is sufficient; when a

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BVX parliamentary group is desired, close a solvent » extraction and one or more distillations and if a maximum amount of benzene is to be produced, one can the alkyl side chains of the alkyl aromatics with a De « remove alkylation «

Di · further details of the traversed are hereinafter explained in more detail with reference to drawings, there show%

Flg. 1 · => a complete picture of the process for producing a HOchataenge «λ motor gasoline; {

Figures 2A and 2B are a flow diagram of the process for producing the maximum amount of BTX® Fraktlon.

An extremely unstable, liquid by-product fraction from the steam cracking of a liquid petroleum, for example an oas oil, is used as the feedstock. This input material contains, inter alia, cyclopentadiene, styrene, dioyclopentadlene and aoetylenic hydrocarbons. This preferred Einsatzmaterlal boiling in the range of 10 to 260 and usually 35 bis.220 ° C, The Qesamtolefingehalt of the feedstock is from 5 to 40 wt. £, including 2 to 20 OEW. £ of monoolefins and 1 to 20 * Qew.% Of Diolefins; the aromatic content is 40 to 90% by weight, the sulfur content is at least 100 ppm and usually between 100 and 4,000 ppm, the oleum content is 1 to 1,000 mg / 100 ml, while the bromine number is at least 50 and generally between 50 to 125 lies. If necessary, other unstable fractions can be mixed with the steam-cracked fraction. It is useful

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the gum · and sulfur content in these fractions by a Alkali treatment with redistillation and / or hot leaching to remove «but it is just a feature of @rflndungs => according to the procedure that you switch off these pretreatments can.

In the case of the one in Flg. 1 is eir usual steam-cracked Rohsohwerbenzln or naphthen, which has the properties given in the column of Table I and is extremely unstable, passed via line 1 into the hydrogenation reactor 2, via lines 1 and 3 is a 75 to in the reactor Gas containing 100 % hydrogen is introduced. Any hydrogenation reactor can be used for the first hydration stage. In general, the reaction is initiated by heating the hot. Gas containing hydrogen is passed through the reactor and the desired temperature is generated in the catalyst bed, whereupon the steam-cracked Sohwerhenzln is added in liquid form.

The catalyst of the first hydration stage is a nickel " Tungsten catalyst on a carrier, such as aluminum oxide «kieselguhr, silicon dioxide-freex» clay, bauxite, or mullite like · alumina is the preferred carrier ?, the catalyst is sulfided. The catalyst can be about 2 to Contains 6 weight pounds of nickel and about 10 to 20 weight pounds of tungsten, while the remainder is alumina. The nickel / tungsten ratio is preferably 4 t 1 to 5: 1. The catalyst can be made from the metals or from the salts, e.g. oxides, nitrates, chlorides and the like. Soluble compounds, such as nickel nitrate and Ammonium meta "or para ° tungstate are preferred"

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Preferably, the Bintrittstemperatur is for the reactor 145 and, for example, between 65 and U5 ⁰ C, about 15O ⁰ C setst at greater Dloleflngehalt of use "- the catalyst bed to materials. The temperature rise in the bed should not be more than 15 to 205 ° C * The average reaction temperature is around 105 to 260 ° C ; H & aktionsdrüoke 28-70 kg / ßir suitable ,, The Börehsatzgesehwindigieeifc is 0/55 to B ₉ QY / is best 1000-2000 SCP / B t / V "The hydrogen / Suhwerbeiüsin ^ Verhältfiis, Bie Heekticn is siit in the essential liquid phase through which _u The temperature control can be done with the treatment gas or with the returned product. This first hydrogenation step is thus characterized by a low temperature, mild reaction conditions and low hydrogen consumption.

In the first hydrogenation stage, mainly the diolefins are lung-converted into monoolefins to stabilize the fraction Because of the great activity of nickel-tungsten ~ Catalyst and the low reaction temperature the formation of polymers and coke, which would otherwise poison the catalyst, avoided. The aromatics are not hydrogenated under these reaction conditions. So far used catalysts such as metallic nickel, platinum and palladium are much less suitable because they are very sensitive to the unstable, sulfur-containing feedstock « lioh are, ao that when using such catalysts the feed material has to be pretreated considerably. Of the The catalyst used in the first hydrogenation stage is on

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nasty catfish regenerated with steam and air »

The partially hydrogenated fraction is then üb © »» Ulm INTR the second hydrogenation stage 5 is fed _a .BraeSs- you and
guidance takes place in the usual manner · W «sb» there is not enough hateful substance in the «material routed through line k
1st »came» further fresh or circulated hydrogen should be given «The working conditions for the second Hydrlerstuf® depend partly on the required saturation and the dosü I®to @ f @ l to be removed ο De the set material in the © rsfcsn Hyäi »iQs = 3t? ai? os has been set, can jet-ssfc higher ©
Working conditions and usual catalysts ^ ei-wenu®t In general, at temperatures "won 205 °, pressures of 14 to 70 kg / em ?, Suireteefe
from 0.5 to 5.0 V / h / V and water tofÄ ^
I500 SCF / BBL worked

Suitable HydrofiRiarkflfeal ^ ste ^ a ffiJP the s ^ side stage contain an essential component several metals of Group VI B and VIII B of the periodic Systems on a suitable carrier such as platinum, palladium, nickel, tungsten, cobalt and molybdenum in elemental form or as SaIs, wl @ as Ojtyd, Sulphate, Nitrate or the like. Nickel, tungsten, cobalt, molybdenum or mixtures thereof are preferred, such as reduced nickel, tungstate, nickel molybdate and cobalfe molybdates Aluminum oxide, clays, bauxite, kieselguhr, molecular sieves, and silica activated alumina can be used as carriers or magnesia, charcoal and the like can be used. before It is beneficial to use the catalyst with

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BADORt & INÄt

or CS ₂ su sulfide. Sulphurized cobalt molybdate on old silica-stabilized alumina is best because it favors the saturation of the olefins and best effects the removal of sulfur. The aromatics are not or only completely hydrogenated.

The stabilized product with a reduced content of olefins. Olefins and sulfur are passed via line 6 into a separating device 7, in which the gaseous fraction is withdrawn overhead through line 8 and partially or completely fed back to the reactor of the first hydrogenation stage via lines 8, 9, 3 and 1. A part of the oasis can be removed from the system via line 10. If necessary, HgS or other impurities can be removed from the gas. The liquid product is passed via line 11 into the stripper 12, where it is preferably partly returned via lines IJ and 1 of the first hydrogenation stage or via lines IJt ₉ 14 and 4 of the second hydrogenation treatment. In order to increase the temperature of the recirculated liquid to the temperature required for the second hydrogenation stage, a heating device 15 is also included.

The light fractions are removed from the scraper via the Line 16 withdrawn and the liquid components passed via line 17 into a fractionation device 18. That desired end product «, for example, a look at the

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BADORtSINAt.

aromatic motor spanning the entire boiling range petrol, is withdrawn from the system via line I9. One containing dl heavier fractions and polymers Fraction is withdrawn via line 20.

The following example shows the suitability of the © rfistdtrag®- must be followed when processing high-eeterefelhaltige Ejünsatzmaterlal with high proportions of Olefinesv Residue or gum.

example 1

A from the Dampfkraekwsg b © £ was used as input material Naphtha or Sehwerbengiia accruing from ethylene production (Ce up to 225 ° C) uses its properties in gap © I of Table I are given.

This inferior feedstock was passed over a ready 2k days in Qebraiaeh catalyzer borne "over this Nlokel-Wolfrafii catalyst on alumina had already been passed enough steam = = cracked heavy gasoline of the present type and other origin" so that a hydrogen sulfide equivalent of more than 20 Qew. £ of the catalyst was formed. A metallic gap catalyst wtird® W has already been completely used up and a noble metal catalyst would be considerably damaged by such an amount of sulfur. Furthermore, these heavy fractions with a boiling point of, for example, 225 ° C and the 327 mg of gum per 100 ml would also have considerably reduced the effectiveness of the noble metal catalyst. Even so, this resulted in a sulphurized nickel-tungsten catalyst

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138 ° C inlet temperature and 330 ° C outlet temperature, at a pressure of 56 kg / cnr, at a throughput of 0.5 V / h / V fresh input material and 0.17 V / h /? return· led product and I500 SCF / B of a 70% water = · stöffgases in the last two columns of the following Results listed in Table Z.

Table X redistilled End product redistill 37.4 all in all 3806 Input material 45.5 . 37o8 46 Weights in ⁰ API total of 3 186 46 190 ASTM IBP at ⁰ C 35o4 O.15 244 0.016 FBP in ⁰ C 46 72.3 0.17 34o2 Sulfur in weight £ 224 20.5 31.2 1.9 Bromine number Cg / g O.23 1 1.1 1 ^WK 235 78.9 . 6th Gum content in
mg / 100 ml 20.1 100.8 102.2 Octane number +
2 ml TEL 327 85.0 - 87.6 Research number - Engine number • -

The UVKg value corresponds to the content of conjugated olefins in percent by weight; the designation TEL means teraethyl lead.

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- ίο

The above table shows "that the bromine number of the feed clay was reduced to 78.9 51.2 and Quia" content of J27 mg / ml was reduced 100 "Despite the high Sphwefelgehaltes and the large amount of the highly olefinic mi Gum Einsstzmaterlals" rar it read nooh. possible to remove 90 to 95% of the gumblldende diolefins with the nickel-tungsten-kafceiysafcor under the present working conditions. The bromine number of the end products can readily in a conventional second Btwte to 3 or less reduced "to aromatisefe® ¹ Ltteungs- e * Central duroh extraction or to obtain @ © at foeliebig lowered bromine number with Moterenben ^ ι ln

In this example, the catalyst used in the second stage. If the product is treated in the second stage at the above-mentioned T @ mp @ ratei * @? less than

1 ppm. This product ■ ::; i., min excellent feedstock for the isolation of aromatic fractions and certain aromatics, such as benzene _e The catalyst of the second stage can be regenerated in the usual way.

In the process shown in FIG. 2 , according to the invention, both motor gasoline and an aromatic fraction containing benzene, toluene or xylene are obtained. A steam-cracked heavy gasoline crude fraction with the properties according to Table Σ with a boiling range of C ₅ to 220 ° C is fed via line 1 to the hydrofining reactor

2 fed to the first stage. Hydrogen containing oas consisting of fresh treatment gas and circulated gas is supplied via lines 3} and 1 of the hydrofiner device

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- ii

suggests. The hydrofining is done in the same way and carried out under the conditions as in Example 1. The partially hydrofined product is about the pipe 4 passed into a separator 5 »from which the oasis phase over Head pulled over the line 6 and partly duroh the Line 7 is removed from the system. The rest of the gas gets old or without the usual cleaning through the pipes 8 «3 and 1 returned. Fresh treatment gas is supplied via line 9 »The partially treated Part of the fraction is then fed via line 10 to a scraper or a tablet removal device and partly returned via line 12. The light ones Fractions are removed from the stabilizer via line 13 The stabilized * partially hydrogenated liquid is drawn off via line 14 into the fractionation system 15 given, from which a stabilized fraction with a Sledebereleh of about J8 ° C and a ZBP of about 71 ° C overhead through the line 16 sucked off and into one Collection container for motor fuel is directed. The end point of this group depends on whether the procedure either to increase the proportion of benzene or the BTX fraction should be carried out. The stabilized fraction boils at about i§0 ° C and has an IBP of about 220 ° C. The end product is via line 17 as J Bypass stream withdrawn from the fractional clonator and mixed with the motor fuel components in line 16. The heavy ones. Shares and polymers boiling above 220 ° C containing fraction is removed via line 18.

The benzene fraction (70 to 93 ° C) or the ΒΪΧ fraction (70 to 150 ° C) is via line 19 of the second hydro »

AU-

Finierstufe 20 / headed, in which the working conditions and

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the catalyst correspond to the method described in FIG. The working conditions are set so that the sulfur concentration in the aromatic fraction less than 20 ppm and preferably less than 1 to 5 ppm. The hydrofined and hydrodesohulphurized Aromatic fraction is passed through line 21 into separator 22 (Pig. 2 B), from which the gas fraction is passed overhead Is withdrawn via line 8. This gas is returned to the first hydrofining plant with or without cleaning Stage fed. The hydrogen-free fraction becomes over the line 23 is fed to a stripper 24, with a part this fraction can be returned via line 26 can. The light fractions are via line 25 withdrawn and can be used as fuel. The enriched liquid aromatics are over the line 27 passed into a solvent extraction system 28. the Extraction takes place under conventional conditions with solvents selected for aromatics such as alkylene glycol, Dimethyl sulfoxide and suIfolane. Preferably after the Udex process worked with a mixture of alkylene glycol and waeeer as extraction agent. The saturated one Raffinate containing hydrocarbons is drawn off overhead via line 29 and mixed with other motor gasoline constituents mixed in line 16. Optionally, all or part of the raffinate can be used Be returned via line 30 to the steam cracking plant. After the usual solvent extraction the aromatics in the fractionation system 32 passed to the to isolate individual aromatics from the benzene via line 33, toluene via line 34 and xylene via the Line 35 is withdrawn. This is only shown here in a simplified manner » Fractionation is usually posed in several towers

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carried out. A fraction boiling above the boiling point of xylene is used as the bottom product from the fractionation » system Deducted via line 36 and with the engine fuel components Mixed in line 16 "

In another embodiment of the process according to the invention, the liquid aromatic fraction is passed from line 27 into a dealkylation plant. The benzene "content is increased" by converting the higher-boiling alkyl aromatic compounds into benzene. The transalkylation can be carried out thermally with 1 to 6 mol of hydrogen at 56O to 730 ° C or catalytically with chromium oxide, vanadium oxide, molybdenum oxide, cobalt oxide, nickel oxide or tungsten oxide or their mixtures on a suitable carrier such as alumina or silica and potassium oxide-containing alumina, such as ₀ 9 "p 46-95 (1964) 1st described in" Petroleum Chemistry and Refining ", Volume,

The inventive method enables an effective, cost-saving and economical processing of the ever increasing quantities of raw materials. Unstable, fluid By-products from steam cracking for ethylene production. Here j the first process stage and its effectiveness is to be regarded as particularly surprising, since the feedstock at low reaction temperatures without excessive Hydrogen consumption is stabilized and furthermore the costly pre- or post-treatment for sulfur removal can be eliminated. If the aromatics have not separated are »the stable and sulfur-free gasoline obtained in the process has an octane number of over 100. That Benzene obtained from the extraction or dealkylation is of a quality suitable for the production of cyolohexane.

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Claims (1)

(6048) Hamburg «February 21, 1969 Patent sayings 1., Process for processing raw, Heavy naphtha, characterized _s that a) the front 105260 C converts the heavy naphtha in liquid * phase with © inen-containing gas in a first under mild conditions at Temperatisr®si ° in the presence of a sulphided supported catalyst to a diolefinfreien, partially hydrogenated naphtha, b) at least a part of this Commercial interest in a second, higher level below stricter conditions with a gas containing hydrogen in the presence of an inert supported catalyst *! of metals of G? v.pps? ϊ B or VIII B of the periodic view Systems Sen Main part of the alkene © in the alkane walks and c) the stabilized heavy petrol station isolates ® 2. The method according to claim 1, d © dui ^: 3ti one from the product of the first
aromatic hydrocarbons and fraction boiling at 37 to 220 ° C! © ^ oma in this fraction in the second ifydrierstnf © 205 ° C with a hydrogen-containing class. They are all hydrogenated to alkanes, the sulfur without saturation of the 909840 / U08 BATH ORIGINAL Arooaten removed and the sulfur-free aromatic fraction isolated· ? · Method according to claim 1 and 2, characterized by that is used as a catalyst in the second hydrogenation stage Nickel, tungsten, cobalt, molybdenum or mixtures thereof; in particular sulfided cobalt molybdate on a carrier used. 4 «Method according to claims 1 to 3, characterized in that that you have a raw heavy gasoline with a feedstock Olefin content from 10 to 30 weight percent, a dolefin content from 1 to 20 wt. £ and a bromine number of at least 50 used· 5. Method according to claims 1 to 4, characterized in that that the inlet temperature in the first hydration stage is less than 14? ° C. 6. The method according to claims 1 to 5, characterized in that that the temperature difference of the catalyst bed of the first Ifydri first stage is in the range from 15 to 205 ° C. 7. Process according to claim 2, characterized in that the aromatic hydrocarbon fraction obtained extracted with a solvent that is selective for aromatics. 9098A0 / 1408 8. The method according to claim 2, characterized in that the sulfur-free, aromatic hydrocarbons-containing fraction is passed into a dealkylation plant and this is dealkylated in the presence of hydrogen to give extremely pure benzene. 9. Process according to Claims 1 to 6, characterized in that the catalyst used in the second hydrogenation stage sulphidated cobalt molybdate on an alumina and 1 to Carrier containing 10% by weight of silica is used. uetsch 909840/1 408