DE1197875B - Process for the production of perchlorethylene in addition to trichlorethylene - Google Patents

Description

GERMAN

PATENT OFFICE

EDITORIAL

German class: 12 P -19/02

Number:
File number:
Registration day;
Display day:

1197875
P27037IVb / 12o
April 25, 1961
August 5, 1965

Modified deaconchlorination (or oxychlorination * rungen), are reactions in chemical plants in which chlorination processes on a large scale Their advantage is due to the fact that they are the HCl by-product, the is obtained in conventional thermal or catalytic chlorination processes, effectively utilize them. The. in the Description and the claims mentioned Qxychlorierungsreaktionen relate to processes, where gaseous hydrogen chloride and a * ° oxygen-containing gas, ζ. B. Air and that to be chlorinated Hydrocarbon or chlorinated hydrocarbon in contact with a metal halide as an oxyphlorination catalyst HCl is consumed in these reactions and the organic starting material is chlorinated. With another Embodiment of this process is elemental chlorine, an oxygen-containing gas and the gas to be chlorinated Hydrocarbon or chlorinated hydrocarbons in contact with a metal halide catalyst brought. The chlorine reacts with the hydrocarbon and / or chlorinated hydrocarbon to form of hydrogen chloride and a chlorinated product of the hydrocarbon and / or chlorinated hydrocarbons .. The hydrogen chloride produced in this way is used up and its chlorine content becomes further chlorination of the hydrocarbon and / or carbon dioxide present in the reaction zone used

In the oxychlorination of 1,2-dichloroethane, at the 1,2-dichloroethane, an oxygen-containing gas and a chlorinating agent, e.g. B, HCl or Cig, in the presence of a metal halide as Oxychlprie.ru.ngskatalysator are converted, two perchlorethylene is obtained, but large amounts are pft of the organic raw material is oxidized or burned, causing a serious loss of productivity entry. The reactions are often difficult to control, especially when chlorine as Chlorinating agent is used, in both cases the yields are far from the desired level removed, and in reactions in which the Difficult to control temperatures, the catalyst losses are quite high.

The present invention is a process for the production of perchlorethylene, trichlorethylene besides that draws gekenpb characterized is that one in a first stage 1,2-Dichlpräthan at 344-455 ⁰ C with 0.25 to 1.5 moles of chlorine per mole of 1, 2-dichloroethane is chlorinated in a manner known per se and, in the second stage, the. SP obtained reaction products in the presence of Sauer processes for the production of Perchlpräthylen
next to trichlorethylene

Applicant:

Pittsburgh Plate Glass Corporation,

Pittsburgh, Pa. (V. St, A.)

Representative:

Dr, W. Beil, A, Hpeppener and Dr, H. J, Wplff,

Lawyers,

Frankfurt / M.-Höchst, Adelonstr. 58

Named as inventor:

Lester Ernest Bohl,

Albert Philip Muren,

Raymond Melvin Vancamp,

New Martinsville, W. Va. (V. St. A.)

Claimed priority:

V. St ν. America May 12, 1960 (28 521) -

stpff and a metal catalyst at 383 bis. 51Q ^P Q pxychlorinated,

When carrying out the initial chlorination stage according to the present invention, 1 mol of chlorine is introduced into the chlorination reaction for every M 1 of 1,2-dichlprethane used. On the other hand, excesses over the preferred amount of chlorine can be used in the initial reaction zone. De; r · Chlprübersphuss for the. Gesamtreaktipn is sq controlled that less than 1.5 MpI chlorine perp MpI 1,2-dichloroethane used are fed to the Gesamtreaktipn. If necessary, a chlorine charge can be maintained that is considerably below the preferred MpI: MpIr ratio. Thus, for example, can .z, only y ₄ Mpl chlorine or less' prp Mpl of the Reaktipn "fed l, 2 = _B D.iehlpr ethane can be used.

The amount of oxygen used can be considerable; fluctuate, preferably prp MpI of the 1,2'Diehlpräthftns introduced into the reaction zones in the ÖxychlprierungSStlife IMpI oxygen vgrwejidfit. ^{But only} 0.25 MpJ of oxygen per mole of dichloroethane introduced into the reaction can be used, and oxygen excesses of no more than 5 moles of oxygen per mole of 1,2-chloroethane can be used, oxygen in

509 629/459

larger amounts than a 5 molar excess The special properties of the Oxy leads generally harmful effects, such as the chlorination stage, the catalyst support used is excessive Oxidation of the present chlorocarbons depends on whether the reaction takes place in a dormant Hydrogens. Usually the oxygen bed or a fluidized bed will take place or Delivery regulated so that 5 per mole of 1,2-dichloroethane are not. If a fluidized bed process is envisaged, so between 0.5 and 2 moles of oxygen used, a carrier will be used for the oxychlorination step. applies, the high utilization of the catalyst in the initial reaction between 1,2-dichloroethane materials and a good distribution of the catalytic and chlorine is allowed the temperature between 344 and material while as a result of agitation 455 ° C held. In this zone, the preferred io and the contacts of the particles are within the reac working temperature generally only minimal abrasion loss occurs in the area of the tion layer. 365 to 438 ° C. The in the presence of the metal halo genid oxychlorination catalyst taking place oxy processes, in particular, the .oxychlorination stage, Cloning reaction is carried out at a temperature between, preferably in a tubular reaction vessel see 383 and 510 ° C performed. A preferred * 5 with an inside diameter of about between Range for the working temperature is 415 to 455 ° C. 0.63 and 15 cm carried out. Procedure with dormant In the oxychlorination zone, the reaction takes layers with a diameter greater than 15 cm Starting materials at higher temperatures limitation prove to be inexpedient. That Considerable too, however, larger fluidized bed processes can also be preferred, since the entMengen Chlorinated hydrocarbons are burned 3 ° removing the heat from it is not such a serious problem than at lower temperatures. as in the case of the method with a stationary layer,

The contact times in the chlorination zone are because processes with a flowing layer provide better heat

0.25 to 20 seconds, preferably 2 to 5 seconds. Have transmission properties.

Contact times above the upper limit of the above When carrying out the invention

described area should be avoided. 25 Oxychlorination reactions can be a catalyst carrier

During the oxychlorination reaction, such as silica, alumina, diatomaceous earth, kieselguhr Contact times regulated so that the reactive and pumice stones are used. A special one Gases 4 to 25 seconds or longer within the effective substrate for a procedure using Reaction zone are maintained. During the oxy-dormant layer there is diatomaceous earth. The same Chlorination reaction can therefore contact times 30 carriers, those with copper chloride, zinc chloride and be used, which is impregnated with calcium chloride mixed for significantly more than 20 seconds, turned out to be lie. Preferably, the oxychlorination reaction is also found to be very effective in carrying out the in a range between 5 and 12 seconds by the oxychlorination reaction according to the invention. A led, Particularly effective carrier for the one made from copper chloride

The reaction is controlled so that at least 35 and potassium chloride mixed catalyst and / or 90% of ^m, the chlorination introduced mol for the consumed copper chloride, calcium chloride and zinc amount of chlorine wefden and that the chloride mixed catalyst when used in the outflowing reaction gases less than 5 Volume fluidized bed process is fuller's earth,
percent, preferably less than 3 percent by volume. In the preferred embodiment of the inventive elemental chlorine. 4 ° according to the method, the first stage is one

In addition, the amount of chlorine supplied should not be chlorination in the vapor phase at elevated temperatures.

more than 1 mole of chlorine per 1 mole of 1,2-dichloroethane temperatures. Can also be used in the first

be. Stage also catalytic chlorination at lower

The temperature taking place according to the present invention and carried out in the liquid phase Reactions can be done in a dormant 45 process. In proceedings in which such Layer or in a process with fluidized bed chlorination is carried out, the reaction or in a combined process with dormant products before their introduction into the oxychlorinationxmd swirling layer. level evaporates. The oxychlorination reaction will

Since both the chlorination and oxy in the vapor phase at elevated temperatures

Chlorination reaction carried out considerable amounts of heat freely 50, and all in the reaction zone

should be on each cooling unit for the reacting materials should preferably be in the

nen or reaction zones are a device for tem- vapor state.

temperature control of these reactions or zones before performing a vapor phase chlorination

be seen. tion in the first stage are 1,2-dichloroethane

For the oxychlorination of the products from the 55 and chlorine in a tubular reaction vessel.

Chlorination zone can be used as a catalyst, which leads to the desired reaction temperature

known oxychlorination or Deacon catalyst is heated. This is where the chlorination takes place

use. These catalysts consist of tubular reaction vessel with a metal used

halides, preferably chlorides of a more inert material filled. Becomes the chlorination stage

valuable metals such as copper, iron and chromium, in 60 in one process' with a whirling layer

Connection with other metal halides, as leads, the reactants become self-

Alkali chlorides, alkaline earth chlorides, cracking catalysis understandably only in an inert fluidized bed

gates, such as zinc chloride or mixtures of these, materials such as unimpregnated carrier particles and

The preferred catalyst for this reaction is sand.

a catalyst consisting of copper chloride, 65 which from the oxychlorination stage or reaction

Zinc chloride and calcium chloride, a particularly effective zone emerging products are in the-

The same catalyst for this process consists of the vapor phase and contains, in addition to the chlorinated ones

Copper chloride and potassium chloride. organic products contain considerable amounts of water

10

as well as some HCl, CO and CO ₂ and undesirable chlorinated organics and hydrocarbon gases. In general, the organic products from these reactions are condensed and / or absorbed and, after cleaning and water removal, are removed in a conventional manner, e.g. B. by fractional distillation or selective absorption and desorption processes, separated from each other.

Example 1

a) 110.8 g of CuCl ₂ -2H ₂ O, 89 g of ZnCl ₂ and 955 g of CdCl ₂ were dissolved in 200 ecm of water at room temperature. 1000 cubic centimeters of cylindrical diatomaceous earth tablets with a diameter of 0.63 cm and a length of about 0.63 cm were placed in a rotatable drum. The drum was set in motion and the solution containing the metal chloride was squirted onto the tablets. After completion of mixing the tablets in an air at 100 ⁰ C were dried.

b) As the chlorination reaction vessel, a tubular reaction vessel made of nickel with a Internal diameter of 3.81 cm and a length of 3.65 m used. The reaction vessel was opened on a Length of 3.07 m filled with simple tablets of diatomaceous earth that do not contain catalyst solution were impregnated. The reaction tube was surrounded by a steel jacket, which was a heat transfer medium contained.

The reaction tube was placed in an upright position and a mixing T was attached to the top of the reaction tube. The 1,2-dichloroethane was introduced from a measuring pump into a steel evaporator 76.2 cm in length, in the jacket of which there was steam at a pressure of 11.9 kg / cm ² . The steel evaporator has an inside diameter of 5.08 cm. Chlorine was introduced from a cylinder through a 77 ° C steel preheater filled with 0.63 cm Berl saddles and through a rotameter into the mixing T at the top of the reaction vessel. At this point the 1,2-dichloroethane and chlorine were mixed and introduced into the reaction vessel. The stream exiting the reaction vessel was drawn from the lower part of the reaction vessel through a pipe and introduced into a second reaction vessel.

A second reaction vessel was connected to the first reaction vessel through the outlet tube located at the lower end of the first reaction vessel and consisted of a reaction tube which was in a vertical position. This second reaction tube had an inner diameter of 3.81 cm and was made of nickel. The reaction vessel was 3.34 m long and was filled with the catalyst material prepared according to Example 1a over a length of 2.73 m. This reaction vessel was surrounded by a steel jacket with an inner diameter of 10 cm. The boiling heat transfer medium (a eutectic mixture of diphenyl and diphenyloxide) was kept in the steel jacket under a pressure of 12.25 kg / cm ² condensed in a tubular heat exchanger with an impermeable graphite shell surrounded by a water jacket. The exhaust gas from the heat exchanger was then passed through separators cooled with dry ice acetone. The non-condensable exhaust gas from the separators was successively through a filled washing column using water as a washing agent and then through a lower Using 14% caustic soda as the washing solution, a filled washing column was passed to the reaction vessel of the first stage, a mixture of 1,2-dichloroethane and chlorine being fed in. The gases emerging from the reaction vessel of the first stage were mixed with oxygen , and the resulting mixture was introduced into the second-stage reaction vessel. The results of these operations are shown in the following table:

( a coat Chlorination stage Be Contact a coat Oxychlorination stage MoIO ₂ Contact Kataly temperature dispatching Time temperature Mole C ₂ - Time sator Working Reaction relationship Se ⁰ C layer link Se age corridor ⁰ C vessel MoICl ₂ Customers 357 tempe 0.53 Customers hours No. 370 temperature MoI-C ₂ - 14.3 357 rature 0.66 8.2 103 357 link 12.7 357 ⁰ C 0.60 7.1 117 344 ⁰ C 0.83 14.0 357 424 0.65 7.5 128 1 344 407 0.88 18.7 344 424 0.68 11.3 136 2 370 399 0.81 11.9 430 7.0 207 3 368 0.86 416 4th 416 0.90 416 5 416

Mol percent yield based on the dichloroethane used

Operation
No. C ₂ HCl ₃ C ₂ Cl ₄ C ₂ HCl ₆ O2-E12C / I4 CO and CO ₂ AC 1 16.3 30.6 1.4 28.4 1.9 6.5 2 14.3 26.2 1.2 . 35.5 4.2 0.1 3 19.1 23.7 0.5 28.0 4.0 1.6 4th 14.3 27.3 2.1 32.6 4.8 6.8 5 8.7 30.2 0.0. . , - .39.0 5.0 7.0

Claims (3)

7 8 claims: presence of a copper chloride catalyst by ' 1. Process for the production of perchloric acid leads, ethylene in addition to trichloroethyene, characterized by 3. The method according to claim 1 and 2, characterized indicates that one is in the first stage. characterized that one is the first stage 1,2-dichloroethane at 344 to 455 ° C with 0.25 to 5 obtained reaction products with 0.25 to 5 mol 1.5 moles of chlorine per mole of 1,2-dichloroethane oxychioriert in oxygen per mole of 1,2-dichloroethane. is known to be chlorinated, and secondly —— ^ -— Stage the reaction products obtained in this way. in the presence of oxygen and a metal German Auslegeschrift No. 1 047 760; Catalyst oxychlorinated at 383 to 510 ° C. xq British Patent No. 569,445; 2. The method according to claim 1, characterized in that Ber. Akad. Wiss. USSR 112/73 (1957); lectured indicates that the oxychlorination in in Chem, Zentralblatt 1958, 3558. 509 629/459 7.65 © Bmidesdruckerei Berlin