FR2478624A1 - PROCESS FOR HYDROGENATING HYDROCARBONS WITH DOUBLE NON-TERMINAL OLEFINIC BONDS - Google Patents

Abstract

PROCESS FOR HYDROGENING OLEFINIC HYDROCARBONS OF WHICH AT LEAST A DOUBLE LINK IS IN NON-TERMINAL POSITION ON METAL CATALYZERS ON SUPPORTS AT HIGH TEMPERATURE AND PRESSURE. A CATALYST CONTAINING 50 TO 70 OF ITS NICKEL WEIGHT IS USED ON A SUPPORT CONSISTING OF KIESELGUHR AT A SPECIFIC SURFACE OF 100 TO 180MG, WHICH CONTAINS 85 TO 93 BY WEIGHT OF WIS, 3 TO 8 BY WEIGHT OF ALO, 0.1 A 0.2 BY WEIGHT OF TIO, 1 TO 1.6 BY WEIGHT OF OXIDES OF FE, 0.1 TO 0.7 BY WEIGHT OF MGO, 0.3 A 1 BY WEIGHT OF CAD AND 0.7 A 1, 5 BY WEIGHT OF ALKALINE OXIDES, AND A HOURLY SPACE SPEED OF 0.1 TO 8 LITERS OF SUBSTRATE PER LITER OF REACTION SPACE CAPACITY PER HOUR IS MAINTAINED.

Description

The present invention relates to a method for hydro-

  to generate hydrocarbons with olefinic double bonds, at least one of which is in the non-terminal position, with the aid of hydrogen on a

  nickel catalyst on kieselguhr support.

  The hydrogenation of diisobutene, triisobutylene or tetraisobutene on a palladium catalyst, on sintered alumina or on spinel at a hydrogen pressure of 25 to 30 atmospheres and a temperature of 180 to 220 ° C. is known (US Pat. Federal Republic of Germany Nos. 1,275,525 and 1,518,817). These catalysts have disadvantages: a relatively short service life, a high price due to the noble metal and the need for decomposition

before regeneration.

  SiO 2 or Al 2 O 3 supported nickel catalysts also have short service lives and do not make it possible to reach the desired degree of hydrogenation, expressed by the index.

bromine of the final product.

  The applicant has now found a process for hydrogenating olefinic double-bonded hydrocarbons, one of which

  at least is in the non-terminal position, using an excess of hydro-

  gene on metal catalysts on hot substrates and under

  pressure, this process being characterized in that a cat-

  supported nickel catalyst containing from 50 to 70% and preferably from 55 to 65% by weight of nickel, based on the total weight of the catalyst, the support consisting of kieselguhr with a specific surface area of 100 to 180 m2 / g which contains, with 85 to 93% by weight of SiO still 2 '3 to 8% by weight of Al 2 O 3, 0.1 to 0.2% by weight of TiO 2, 1 to 1.6% by weight of Fe oxides, 0.1 to 0.7% by weight of MgO, 0.3 to 1% by weight of CaO and 0.7 to 1.5% by weight of alkaline oxides, in all cases based on the weight of kieselguhr, and in that a space velocity of 0.1 to 8 l of substrate is maintained per liter of

  capacity of the reaction space and per hour.

  The products used in the process according to the invention are hydrocarbons with olefinic double bonds, at least one of which is in the non-terminal position, and which can be represented by the general formula:

R1 2

"-c = c- (I)

R R4

R23 / 4

  wherein R 1, R, R 3 and R are each independently of one another C 1 -C 22 alkyl or C 1 -C 22 alkenyl, R 1 and R together containing at least 4 carbon atoms, and R and R may besides representing each, independently one

on the other, hydrogen.

  Such olefinically unsaturated hydrocarbons can be obtained, for example, from the oligomerization of propylene and the various isomeric butenes in the presence of acid catalysts such as H 3 PO on activated charcoal or macroporous acidic cation exchangers, and lead to olefinic oligomers containing,

  for example, from 6 to 24 carbon atoms in the molecule. These

  such as isoheptenes, diisobutene, di-n-butene, codimers of isobutene and n-butene, nonene and isononers,

  tetrapropene, pentapropene, and tri-, tetra- and penta-

  co-oligomers of iso- and n-butenes, as well as the higher oligomers of propene and butenes, can be used

  -20 what in other chemical conversions. However, other applications

  industrial processes require conversion of the oligomeric

  the corresponding paraffinic hydrocarbons, which serve, for example, as high-purity solvents for polymerisation reactions, for plastisols, coating products, cleaning products for household use and vehicle maintenance, as well as for insecticidal solutions, aerosols, cosmetics, and also extraction agents for

Fatty substances.

  Isolated double bonds existing in

  gomers in question, who are not in a terminal position, are

  difficult to hydrogenate and, usually, are only hydrogenated

  completely. This difficulty is accentuated if it concerns

  high molecular weight olefinic unsaturated bonds. By

  further, it is preferred to use in the process according to the invention

  straight or branched olefinically unsaturated hydrocarbons having a double bond in the non-terminal position and containing

  at least 10 carbon atoms in the molecule.

  The process according to the invention is carried out with a supported nickel catalyst which is characterized both by its nickel content and by the specific surface and the special composition of its kieselguhr support. The nickel content is, for example, 50 to 70 and preferably 55 to 65% of the total weight of the catalyst. The specific surface of the kieselguhr used may

  from 100 to 180 and preferably from 120 to 170 m 2 / g. The composition

  particularity of the kieselguhr used as a support is

  made by the presence of titanium dioxide. For this composition, in addition to a content of 85 to 93% by weight of SiO 2, a content of 3 to 8% by weight of Al 2 O 3, from 0.1 to 0.2% by weight of TiO 2, from 1 to 1 , 6% by weight of Fe oxides, from 0.1 to 0.7% by weight of MgO, from 0.3 to 1% by weight of CaO and from 0.7 to 1.5% by weight of alkali oxides, in all cases with respect to the weight of the kieselguhr. The kieselguhr used as a catalyst support further has a pore radius distribution such that 20 to 40% is less than 50%, 50 to 50% is 50 to 100%, 4 to 20% is 100 to 200% and go 1 to 6% from 200 to 300 A.

  Kieselguhr containing titanium dioxide and suitable

  Suitable for use in the process according to the invention is, for example, in the Luneburg Heath, Federal Republic of Germany (RUmpp, Chemie Lexikon, 7th edition, volume 3, page 1770, Franckh'sche Verlagshandlung Stuttgart) . Since the extracted kieselguhr undergoes drying and heating treatment in rotary kilns, during which the organic substance is burnt and the volatile constituents removed, the chemical composition of the kieselguhr

  can vary greatly. For the process according to the invention, the composition

  sition must remain within the specified intervals.

  The nickel catalysts on kieselguhr support used in accordance with the invention are prepared in a manner known per se, for example by impregnating the kieselguhr described above with a liquid containing a nickel compound, followed by drying and, if necessary, cooking kieselguhr

  impregnated and a reduction of the nickel compound

  active ingredient, for example using hydrogen.

  The process according to the invention for the complete hydrogenation of olefinically unsaturated hydrocarbons can be carried out in the liquid phase, in the trickling phase or in the gas phase in a fixed-bed reactor, a fluidized-bed reactor or a tubular reactor. catalyst remaining stationary in the reactor. The product used can flow from bottom to top or also in a fixed bed reactor or a tubular reactor from top to bottom. Hydrogen can be sent in parallel or countercurrent. If one wants to achieve a regular and complete hydrogenation, it is essential to ensure a good mixture between the product used and hydrogen, a regular distribution of the flow and a uniform contact with

  the catalyst. In a preferred variant of the process according to the invention,

  the olefinically unsaturated hydrocarbons are sent in the liquid phase from bottom to top, with hydrogen in parallel flow,

  on the catalyst in fixed disposition.

  In the process according to the invention, the hydrogen is used in excess with respect to the hydrocarbons and, for example, in amounts of 5 to 30, preferably 8 to 10, moles of hydrogen

  per equivalent of olefinic double bond.

  The process according to the invention is carried out at a temperature of 100 to 3000 ° C., preferably 150 to 220 ° C., and

  a pressure of 10 to 80 bar, preferably 15 to 30 bar.

  In the method according to the invention, a hourly space velocity (abbreviated hereinafter LHSV "liquid hourly space velocity") is maintained from 0.1 to 8, preferably from 0.2 to 6 liters of substrate per liter of capacity of the reaction space and per hour. Due

  the growing difficulty, already mentioned above, of hydro-

  When the number of carbon atoms increases, it is further recommended to decrease the LHSV when the number of carbon atoms increases. As a result, a preferred variant of the process according to the invention consists in converting olefinically unsaturated hydrocarbons, for example oligomers of propylene or isomeric butenes containing mainly hydrocarbons.

  approximately C10-C14, at an LHSV of about 4 to 6. A preferred variant

  of the process according to the invention, for the implementation of hydro-

  olefinically unsaturated carbides containing mainly

  14 to 18 carbon atoms, consists in maintaining an LHSV of about

  1.5 to 3.0. Another preferred variant of the process according to the invention

  for the use of hydrocarbons with unsaturated

  finely containing mainly from about 18 to 24 carbon atoms,

  is to maintain an LHSV of about 0.2 to 0.5.

  The hydrogenation according to the invention leads to hydro-

  saturated carbides whose residual unsaturation, expressed by the bromine number, is less than 1 and, preferably, less than 0.4 g of Br 2 per 100 g of hydrogenated product. Under the best circumstances, at the hydrogenation of olefinically unsaturated hydrocarbons containing about 12 carbon atoms, bromine numbers of less than 0.2 g of Br 2 per 100 g of hydrogenated product are attained. The catalysts according to the invention achieve service times in excess of 8000 h when the olefinically unsaturated hydrocarbons used are distilled fractions, originating, for example, from the oligomerization of alkylenes. However, the catalysts according to the invention still achieve durations of

  over 4000 hours when used as a hydrocarbon

  Olefinically unsaturated burs products of distillates obtained for example as residues at the separation of alkylene oligomerization fractions and which, in general, are more complex and contain more impurities. These bottom products can not be hydrogenated satisfactorily with the aid of

  palladium catalysts of the prior art.

  In addition to these noble metal-based hydrogenation catalysts, other nickel catalysts with nickel contents of 50 to 70% by weight on SiO 2 or Al 2 O 3 support, or Raney nickel, for example, have a nickel content. 90% by weight or more of nickel, do not provide satisfactory results

  to the hydrogenation of the higher olefinic oligomers of oligomer

  alkylene, and to date, insufficient bromine indices, greater than 2 g bromine per 100 g were obtained.

  of hydrogenated product, even when observing low values of LHSV.

  All of the hydrogenation catalysts mentioned, used with the

  olefinically unsaturated hydrocarbons to be used in accordance

  according to the invention, containing non-terminal double bonds,

  have significantly shorter service lives than those

  lysers used according to the invention. It is surprising that the catalysts according to the invention outperform known palladium catalysts since, in general, nickel-containing catalysts require much higher pressures and temperatures (Ullmann, Enzyklopadie der Technischen Chemie, 4th edition, volume 13, pg. 136, Verlag Chemie 1977) and olefins with non-terminal double bonds are more difficult to hydrogenate than olefins containing only terminal double bonds (Tetrahedron 16,

16 (1961)).

  The following examples illustrate the invention without limiting it; in these examples, the indications of parts

  and% are by weight unless otherwise indicated.

EXAMPLE 1

  The product used for the hydrogenation is a mixture of C 12 iso-olefins obtained from the oligomerization of mixtures

  of butenes. At a reaction temperature of 180 to 220 ° C, a pressure of

  25 bar total pressure, 20 bar hydrogen partial pressure and 5 LHSV, various catalysts were

  nickel and palladium, and it has been determined in

  along with their hydrogenation activity. Table I below gives the results obtained in a comparison of the catalysts,

  expressed by the bromine indices and the service lives.

  Catalysts 1, 2, 3 are catalysts according to the invention on a kieselguhr support containing 90.2% SiO 2, 6% Al 2 O 2 O 0.15% TiO 2, 1.6% Fe oxides, 0.7 % MgO, 0.3% CaO and about 17 alkali oxides. Prolonged tests highlight the surprising service life of these catalysts, compared to nickel catalysts on other substrates at varying levels of nickel and palladium catalysts on various substrates. Several catalysts do not allow

  to obtain the required bromine number of 0.2.

EXAMPLE 2

  The product used consists of C16 isoolefins from the oligomerization of butene mixtures. The reaction conditions are: temperature: 180 to 220 ° C; total pressure: 25 bars; hydrogen partial pressure: 20 bar; LHSV 2.5. The catalysts subjected to the comparative tests are the mimes

Z478624

  than in Example 1. The results obtained are indicated in the

Table II below.

  Again, it was surprisingly found a remarkable service life of the catalysts 1, 2 and 3 on kieselguhr support compared to other catalysts nickel and palladium; with the other nickel catalysts, again, sufficient bromine indices, preferably lower, can not be obtained.

at 0.4.

EXAMPLE 3

  The product used is a bottom product obtained at the separation of C16 isoolefins from the oligomerization of C mixtures. The mixture consists of 90% C20 isoolefins with a residual content of 6%. % of C16 olefins and 4% of isoolefins with more than 20 carbon atoms. The reaction conditions are: temperature: 200 to 220 ° C; total pressure: 25 bars; hydrogen partial pressure: 20 bar; LHSV 0.3. The catalysts subjected to the comparative tests are the same as in Example 1. The results are shown in Table III below. If one wants to hydrogenate this product of foot of column

  at a required bromine number of less than 1 under the specific conditions

  Only the catalysts according to the invention, 1, 2 and 3, can be used. None of the other catalysts makes it possible to attain the index.

bromine required.-

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Z6 S9 05

  giTlTlAe AuTald V q 000o 8 ap npo ndwoza.lu; jessa Z'0

* / 9 69 LS

  6 i a | L | 9 5 1 [ú 1 Z Z Z go 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F. vJY oo NO. co I

TABLE II

Catalyst 1 2 3 4 5 6 d 7 8 9

_ _ .. __ _.,. I _

  Ni content, 57 69 64 50 65 92 55% by weight Pd content, 1.8 0.5% by weight

  Kieselguhr support A203 SiO2 spord-

  nite-H Br index (Brg index) 0,2> 2> 7> 0,2 0,2 Service life, h 6,000 300-500 100 100 100% a -ce Co

TABLE III

  Catalyst 1 2 3 4 5 6 8 9 Neuron, 57 69 64 50 65 92 55 wt.% 6 Pd content, 1.8 0.5 wt%

  Support Kieselguhr A1 203 SiO2 spike-

  nite-H Br mark (g Br2 / 100 g) <1 5 2 Service life, h 4,000 50-100 20 150 30

  _ _ _ _. _ _ _ .. _ _ _ _ _ _. _..__________________________________ _____________________________________________________

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Claims (6)

REVENDI CATIONS   I. Process for hydrogenating hydrocarbons containing   olefinic double bonds, at least one of which is   non-terminal excess hydrogen on metal catalysts supported on high temperature and pressure, characterized in that a supported nickel catalyst is used at a nickel content of 50 to 70% by weight relative to the total weight of the catalyst, whose support consists of kieselguhr at a specific surface area of 100 to 180 m 2 / g and which contains, with 85 to 93% by weight of SiO 2, 3 to 8% by weight of Al 2 O 3, 0.1 to 0.2% by weight of TiO2, 1 to 1.6% by weight of Fe oxides, 0.1 to 0.7% by weight of MgO, 0.3 to 1% by weight of CaO and 0.7 at 1.5% by weight of alkali oxides, in all cases with respect to the weight of the kieselguhr, and in that a space velocity of 0.1 to 8 liters of substrate per liter of the reaction space and per hour.   2. Process according to claim 1, characterized in that the olefinically unsaturated hydrocarbons are passed through   liquid phase from bottom to top, with hydrogen in parallel current   lele, on the catalyst in fixed disposition.   3. Method according to claim 1 or 2, characterized   when using hydrocarbons with olefinic unsaturation,   high molecular weight, decreases the space velocity   within the range of 0.1 to 8, and vice versa.   4. Method according to any one of claims 1   at 3, characterized in that, when olefinically unsaturated hydrocarbons consisting mainly of products containing from 10 to 14 carbon atoms are used, a speed is maintained. space time of about 4 to 6.   5. Method according to any one of claims 1   at 3, characterized in that, when olefinically unsaturated hydrocarbons consisting mainly of products containing about 14 to 18 carbon atoms are used,   an hourly space velocity of about 1.5 to 3.0.   6. Method according to any one of claims 1   at 3, characterized in that, when using hydrocarbons   with olefinic unsaturation consisting mainly of products -   which contain from 18 to 24 carbon atoms, an hourly space velocity of about 0.2 to 0.5 is maintained.