DE1793572A1 - Process for the oxidation of olefins - Google Patents

Description

DR. ELISABETH JUMG, DR. VOLKER VOSSIUS ₁ DIPL.-ING. GERHARD COLDEWEY

PATENT LAWYERS

• M0NCHEN2S ■ 8 IEOE SS TH AS8E 2β · TIL EFON I4S0S7 · TELEGRAM ADDRESS: IN VENT / M ONCH EN

TELEX 5 29

Aug 8, 1969

1624/1

SHELL IHTEPJiA "? J.ONAJ ⁷¹ RKGMRCH MAATSCKAPPIJ" The Hague, Netherlands

^M Process for the oxidation of olefins "

Priority: March 22, 1967 _r Great Britain, No. 13 486/07 30 October 1967, Great Britain, No. ₀ 49 261/67 »

The invention relates to a process: ur oxidation of olefins urilf ¹ ^ the use of silver catalysts, that is to say of catalysts, which are aun particles of a carrier material coated with a layer of metallinchem .Silber and / or or ^r * i llieroxyi, Lontohon, Von A special parlout is the oxidation of al; hy "if.-n and propylene to the on ^ opposed olefin oxy-

= ■ ^ ^{; !} - * "■ -'''- ta li'.s'-d torf-n t'in-l by Peter

103827/1927

1594 and 1595, and U.S. Patents 2,764,598, 2,766,261 and 2,825,701. These catalysts are produced using a slurry of silver oxide to coat the carrier material particles. Other known silver catalysts are obtained by impregnating porous carrier material parts with a solution of one or more silver compounds and then converting the latter into silver and / or ollberoxide worden-, impregnation methods have been rubbed Bosch z _e B "in Canadian Patent 592 091, in the U, S, -Patentschriften 2 7735 844 and 2,920,052 and in British Patent 1,020,759.

However, the known processes for the oxidation of olefins, in which conventional catalysts are used, provide too low degrees of conversion and selectivities.

The object of the invention is to provide a process for the oxidation of olefins in which new catalysts are used and compared to the known processes provides better degrees of conversion and selectivities.

The method according to the invention for the oxidation of olefins using silver catalysts with a porous carrier material is characterized in that the catalysts evaporate in a maximum of 900 seconds by impregnating the carrier particles and subsequent drastic drying, with at least 80% by volume of the solvent in the impregnation solution, and an-:; ^ _; r ^ - ^ 109827/1927 »AD OWGlNAL

epsjji & ö- or equilateral conversion of the silver compound . In w.8f <\. l ± i'ChGE ' syllables ükw * Silboroxyd have been obtained »

V: t-Y_C-j. I \ r, Gli <3n <l <Bi "X (i ± a <> i h 'i; EI3 inclined found that when Inventions gsmiiE & i ^Tö;; fal.!.. > re: ü von., ie 2 'iilbeirfaUiaXysatoren with the same 5th "ra.gerinats2: -i £ il rmd always the same silver content by the above mentioned rlrastiBciie joy and conversion of the silver TB: ebi:.' /? ang iz .: 813 bor bsi // Silberoxyö. ■ produced is superior to that produced in a STidex'Qn Weiao lier?.?. is »

In clior-ίΠ! Taken together, the identity of carrier materials can only be regarded as complete if not only the chemical coherences>G'ondem also the dimensions and the porosity structures of the particles agree. (With regard to the interpretation of the porosity structure, reference can be made to the German Auslex -; esaHrii't 1 023 849 ₁ column 2 _f . There it is not a question of silver catalysts, but analogous considerations apply to the latter.)

Of course, the group formed by drastic drying silver & atalysatoren such preferable, the composition also previously been sufficient favorable conditions detected.

The impregnation of the carrier material 8 in the production of the silver catalyst used in the process according to the invention can be carried out in a manner known per se. Hur is to be observed _r

109827/192 7 »ad original

Nierlösung dissolved silver compounds to silver and / or an oxidation to silver oxide at the same time with the drastic Troefc- mmg should take place, the chemical conditions for the course of the reactions must be met during the short drying time of silver compounds, but also of sufficiently large amounts of at least one reducing substance in the pores of the carrier material must be taken care of, before the drastic drying is carried out «

Organic compounds which can penetrate into the pores at the same time as the silver compounds, dissolved in an aqueous impregnation solution _{f , Z 0} Bo polyhydric alcohols, are preferred as reducing substances.

Be at erfindungsgemäSen method is preferred catalysts having a silver content of from 3 to 25 percent by _f -. $, In particular from 5 to 15 wt ~ $, based on the weight of the used Trägeraaterials ,, "

It is known through the properties of silver catalysts To improve the addition of promoters, and of course the silver catalysts used in the process according to the invention can also be used contain such promoters.

Alkali and alkaline earth oxides are particularly useful as promoters. A content of these metals in the finished catalyst of Qg ₁ OJ to ύ _$ 5 6ew - ^, based on the weight of the carrier

109 827/1927

terials, is usually sufficient. Voraugswelse the! Carrier material is impregnated with aqueous solutions of such compounds of the relevant metals, which can easily be converted into the oxide, and then dried, the drying not having to be carried out in a drastic manner, as after the impregnation of the invention Process used catalysts with the silver-containing liquid happens. Lithium oxide is particularly preferred as a promoter. at the

You drastic drying of the catalysts used according to the invention can, for example, by means of a sufficiently strong current of a hot grass. When using an oxygen-containing oasis, the daeu can lead to silver catalysts can be obtained in which the silver to a high degree in the front of silver oxide is present. Although air is absorbed as trookenges for economic reasons, gases richer in oxygen, such as ft.B. teohnisoh purer

'■■■■' - £

Oxygen, or else low-oxygen or even oxygen ^

free gases, such as B.B, St conducts off, argon, helium, hydrogen, Carbon dioxide., And all kinds of gas mixtures can be used.

The temperature of the material to be dried is expediently above 25O ⁰ G _1, preferably in the range from 300 to 55O ⁰ C. The tempura of the dry gas troins must be much higher as a rule, do. aonat die Erfordorlicho Gaa ^ oechv / indigkoit and thus also

(ILo rtemgo den "ßn / jnci per ZeI! .Einheit for practical purposes un« u ~ i ;; h.-jch no wUtilQn, Vn. Yawfuvn you for Gaii temperatures in the

109827/1927 * ^A °

range from 700 to IGOO ⁰ C into consideration "

In order to promote the transfer of heat from the rock gas to the impregnated material to be dried, and thereby reduce the necessary ßaamenga au, it can be advantageous to carry out the drastic drying in the rising stream of the Trookengaee, in which solid heat transfer parts are fluidized and on what al oh the catalyst partchon in the Gegon stream

It should be noted that already process for l'roülcnen have become known of granular materials to yield solid bodies contract other grain size as heat ei 'used' It has not yet been proposed previously, the mixture of particles of both types so concluded · λμ cause the sleeveless particles to be fluidized and the drying particles to fall through the fluidized bed.

The advantages offered by the process of the invention through the use of the silver catalysts described above are illustrated by Examples 7 and 8. Examples 1 to & describe the preparation of the eingeoetaten in the method of the invention drastically SSO trockneton catalysts of the aforementioned type.

At Example 1

Kin hand oil usualea iL'Ldigoi'material aua eii-AlgO ^ with a speai- .. OberfiiiuIiG of. less than 1 m ^ / g, with a spe; ilfi-

. ^. : ^ 8 109 827/1927

Pore volume of 0.23 ral / g and with a particle size of 0.074 "and 0.300 mm was first ^{heated in an oven for 2 hours to 50O 0} O. It then contained less than 0.1 wt .- # water * ■

The carrier material was impregnated with a solution of silver nitrate in a mixture of equal parts by volume of water and ethylene glycol. Bie concentration was chosen so that the Öilbßrgehalt of the finished catalyst, based on the carrier material, would be 10.8 wt .- # _c vfurde The material was carried to j? Impregnation over water vapor of 10O ⁰ G predried with stirring until the particles no longer showed any tendency to stick together. The impregnation oeune. (16 »8 wt .- *) h # f« n4 is therefore completely in the pores of the particles and no longer in the spaces between the particles,

The material was then drastically dried by dropping it at a rate of 25 g per hour through a vertically positioned glass tube with a length of 40 cm and a 1 cm diameter glass tube. In this tube an upward current was technically pure oxygen gas Aiit a temperature of 500 ⁰ C maintained "The average for each particle was about 3.5 sec,

Material which has been held down from the pipe, ent · nselä cooling to room temperature less than Gj, t wt .- $> SGLG © a constituents.

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Example 2

The experiment of Example 1 was repeated with the differences that the at SOO ⁰ C getroelmete carrier material impi'ägniert with an aqueous Mthiunüiydroxydlösung and 2 hours at 200 ⁰ C was dried before the impregnation was vorgenoüimen with the silver nitrate solution, the Silbergehslt in the finished catalyst here was 2I _1, 6 wt .- ^, the corresponding lithium content 0.14 {Jew """fp, both based on dan carrier material. Me temperature of Sauerstoffgassea was somewhat higher than in example 1 and was 54O ⁰ C.

The experiment of Example 2 was wiedex few times * _s h.olt with the difference that the drying after impregnation with the Lithiumhyäro2q? Cllö'eu.ng was carried out at higher temperatures. The duration of the Erhitsung was j {3 <Ioeh i \ rie before 2 hours _c In addition, the concentration of the silver nitrate solution was such that the finished catalyst, besogon to the carrier material ', 10 _f 8 öew, - contained ^ silver. The drying temperatures between the two impregnations were; 4-00 ⁰ C, 500 ⁰ G, 55O ⁰ C, 600 ⁰ C and 900 ⁰ C.

Example 4

A commercially available carrier material of the same kind as in Example 1 but with a particle size between 0 _{f P} 6 and 1.6 MRA, was in the same Weis *? as indicated in Example 1 »such

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found that the water content afterwards was less than 0.1. Bas Hatsrlal was then impregnated with an aqueous solution of idthium and, after Erocloien, obtained in air for 2 hours to 450 ^Q <3. It was then again impregnated and washed with a solution of silver nitrate in a mixture of 75 vol. 56 water and 25 vol. Ethylene glycol, pre-drying over steam you 10O ⁰ O, with the sugar content on 7 _t 8. Geisr * "# reduced 3? T iJurae, a drastic Iroclmung took place at 90O ⁰ O using i / on technical rain of oxygen as ¹ JJiO ckengas instead ₆

The finished liataXysat.oi · «contains 0.14 ßew, - ^ lithium and 10.8 Ge-W ₃ -Jo silver, based on the carrier material» bar 3? Liquid content betnui ^ enigei * as 0.1 ClQW ₀ - ^ ·

The procedure of Example 4 was repeated, with the sub decided that nitrogen was used as all dry gas.

Example 6

The procedure of Example 4 was repeated, with the difference that the impregnation with the lithium hydroxide solution and refrain from the subsequent 'notice.' So it was with the silver footstep; solvent impregnated "

According to the examples 1 to 3 manufactured catalysts

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were tested on the basis of the oxidation of ethylene to ethylene oxide for their usability in the process according to the invention. In addition, two silver catalysts that were not dried drastically were tested for comparison. The former of these two catalysts (A) was prepared according to Example 1, but after pre-drying at 100 ^G 0, further drying was carried out by heating in an oven for 3 hours. In the course of the first hour, the temperature was allowed to rise gradually to 30O ⁰ O and during the two further hours the temperature of 50O ⁰ C was maintained. In the preparation of the second catalyst (B), the heating in the oven was replaced by drying in a gas stream with a temperature of 280 ^° C. for 2 1/2 hours. The Troekengas consisted of a mixture of 10 VoI, - $ hydrogen and VoI 90. JS-nitrogen, the content of liquid components in both cases was after cooling to room temperature less than 0.1 wt .- _t 6 exactly as in? the drastically dried catalysts of Examples 1 to 3 *

™ In the tests, the fluidisability was improved 30 g each of the catalyst with 30 g of the untreated Carrier material mixed and the mixture, iv was in a vertical Oil gas pipe with a length of 50 cm and an inner diameter 2.5 cm by means of an upward gas trombia at a rate of 1866 liters per kg of the catalyst diluted with the untreated support material per hour fluidized »The gas consisted of ethylene and air i ^ euiam volume ratio from 1ί19. Ss was under an öruQ & vpn 1.08 ata initiated.

IAD ORSGINAL 109827/1927

The temperature of the fluidized bed was increased to 400 ° C. and this temperature was maintained for 1 hour. During this time, the "ripening" of the catalyst took place. Then was the '! Brought temperature to 26O ⁰ O and at this temperature the Äthylenverbrauch and the formation of Äthyleno ^ yd were determined. There was therefore no recirculation of material that had passed through the reaction zone, as is of course customary in industrial or large-scale plants.

The timing and selectivity percentages are shown in Table I below stated «The percentage of implementation concerns the ethylene consumption with reference to the amount of ethylene added, while the selective growth rate increases the yield Ethylene oxide in relation to consumed ethylene concerns

Table X Selectivity W catalyst Implementation (#) ■ 38.5 A. 23.5 39.6 B. 26.4 45.3 example 1 42.5 59.6 Example 2 44.5 70.2 Example 3-40O ⁰ C 49.3 75.2 Example 3-5OO ° C 46.1 61.8 Example 3-55O ⁰ O 48.2 59.3 Example 3-60O ⁰ C 54.5 40.7 ■ Example 3-90O ⁰ C 60.4

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When testing the catalysts of Example 3 was respectively 40 dee catalyst "with 4-0 g g of inibcjhandelten, üfrägermaterials ver · power," The gas velocity supervising ^one 140Ö liters per kg of with • mboXiandeltem Srägs ^ material -verdünntei ?. Catalyst per hour. The other conditions were exactly the same as with the other reads «

The introductory V / ert © böfstätigSR the excellent degrees of conversion and selectivities, many in accordance with the invention, vjttrden _# especially bsi liiweoenhe.it a promoter.

Example 8

Even with the Examples 4 bit 6 Katalyoatoren produced the erfizidungsgemäßc method was tested using the oxidation of ethylene zn _{Ithyleiiosyd}} 3 ^e tested ^ och under different conditions than in Example 7, also a not drastically dried Catalyst C For comparison "This catalyst had been prepared using the method of example 6, with the difference that subsequent to the predrying over steam, the further drying was carried out as for catalyst B of example 7.

It should also be noted that the catalyst of Example 5 was ^{heated in air at 500 °} C. for 6 hours before the test experiment «,

The oxidation experiments were carried out with fixed catalyst beds. In each case 100 g of the catalyst were used. Of the

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rc 'w «r <nin {blowpipe with a small size of 85 cm and a

siesaer from 1 night? mm · Bie length of the? Catalyst column in the B.aakto :? ua.i? in all cases 60 cm. A gas mixture was introduced under an iron bridge from .I ₉ OS ata into ά, οη reactor »The together« msns-etsuns ■ was either

25 tol "~ $. Ethylene, -8.7 ToI ♦ - # O ₂ , 66.3 Vol.-J ^ H ₂ or

3? Ol .-; i Itlbylea, 97 V0I.-56. Air,

Ss mirclsn ir «imer 3 · 10 ™ ° Hol -! / O ₅ beaogeii on ethylene, a hemp * m

deleprodiiktSs', -jalcla.es -from chlorinated Polyphsnylvertoindimgen consists ρ ia. sä himself, bslramitai *? i5ise as moderator HWgQBetsst »Bie Kontafetaeit gwischea -Reaktionsgemisßh and catalyst fetrug S ₅ 4 brine 230 to 288 ⁰ C content. Bie ^f ieilühön in the fluidized bed make one ausgöseiehnet © Wärmsübartragmig bootcovers "

The 'lest only became "this time after an operating time of 400 ™

Stan & en started at a temperature of 28Q ⁰ O and a gas velocity of 340 liters per kg of catalyst per hour (¥ orperiocle). Only then were the respective experimental conditions set and the ethylene consumption and the formation of ethylene oxide were determined. In accordance with Example 7, material 2 was circulated around the reaction zone.

In the following SabaLXe IX the- Tteetaimgo- and Selek-

1-098 27/1927 SAD om _emAL

tivltätsprosentsat ιλ

Table II

Kat »
Atop Temperature ( ⁰ G) Cat *
Example « Kat-
C. IT-m Selectivity (56) Kat "
Example, Kat
Example, Cat
C. aensetäsung 4th Cat.
ο Baisp. 6th UJE ""
set- Cat *
Example · 5 6th 262 255 236 »AL *. 4th 79 75.9 69.2 ethylene / 270
280 247 262
272 255
278 9.6 78.7 77
75 _ä 74.2
71.0 68f »3
65, δ aaiiersitoff /
nitrogen
> 5.0: 8.7 " 28? 253
^r 54 «. 12.3
16.4 76.9
75.2 72, - S6,3r, 249 276 256 258 19.8 73.7 76.7 70.4 - 260 265 276 45.8 82.9 72.7 68p 2 ethylene / • K »
278 279 288 60.6 80.5 67.2 66 / Scent
5j97 67.0
88.3 75.5 S J 5
4th 9

Table II shows that the catalyst has a much lower selectivity than the drastically dried catalysts of the examples. 4 to 6, at the higher degrees of conversion of the same oils drastically dried catalysts also their increased activity, which 2 «B. the comparison of the temperatures required for a degree of conversion TTGii of about 60 jfi proves. When using the catalyst of Example 4, only 260 ⁰ C, when using the other hand Yergleichskatalysators C 276 ⁰ C are required "

Ber-Katal; yii; \ tor of example 4 lasted more than 3800 hours

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ofH $ NAL

can be kept in operation without worsening the bad brigade _β The catalysts of Example 5 and 1200 hours were kept in operation for more than 580 or 1200 hours, and there was also no damage to the results for stagnation sites.

The compliant. "Ferfakran ■ was tested with the catalyst of Example 4 using the same apparatus using the oxidation of propylene instead of" ethylene. The torpericde was omitted? the transmission and selectivity prospects were determined immediately. The Reaktionsgeiaisch consisted of 25 ¥ olo "$ propylene, 10 Yoi .- # oxygen and 65 ToI -. & ■ The nitrogen Gasgesoliwindigkeit betxng 300 Mter per kg of catalyst per hour was the SSAS viieöerum ciinem introduced under pressure of 1 ata 08 _f.. The count since 9 seconds. The results are summarized in Table III below.

Table III
! Temperature conversion selectivity

2/0 2 55

328 5 20.

»AD OfllGiNAL 109827/1927

Claims (1)

experience aiir OxycLa-biOFi iron olefins using SiI-Herlcatalysatoren fflit porous carrier material, thereby gpkennssiölmetp that the catalysts through. Impregnation of the carrier particles and subsequent drastic drying ₈ in the case of vie-rlg'stexis SO ¥ ol, ~ jS the solvent of the impregnation solution evaporates in a maximum of 900 seconds, and subsequent or simultaneous conversion of the silver compound into metallic silver - or silver oxide have been, Terfaliren according to claim Ij, characterized in that catalysts are used which contain up to 25 Gev / "~ $ and in particular 5-15 wt .- $ silverj based on the support material _p» 3 «Method according to claim 1 and 2 _f gekennaeichaet that catalysts are used which additionally contain alkali and / or alkaline earth oxides as promoters, preferably in consentrations of 0.03 ~ O _r 5 Sew * ~ $ promoter _{metal r} based on the Carrier material " 10 9 8 2 7/1927 _1A d