DE2540067A1 - METHOD OF MANUFACTURING VINYL CHLORIDE - Google Patents

Description

DB.A.VAN DERWERTH DR.FHANZLEDBKR ™ Brille £ ™ DIPL-ING. (1934-1974) ^Ulrl " ^U "

8000 MONKS 80 LUCILE-GRAHN-STRASSE 22

TELEPHONE: (089) 472947 TELEX: 624624 LEATHER D TELEGR .: LEATHER PATENT

September 9, 1975 CHE.3763

THE BRITISH PETROLEUM COMPANY LIMITED Britannic House, Moor Lane, London EC2Y

England

Process for the production of vinyl chloride

The invention "relates to a process for the production of Vinyl chloride by oxychlorination of ethane.

The chlorination of hydrocarbons with hydrogen chloride and oxygen in the vapor phase "at elevated temperatures in the presence of a copper (II) chloride catalyst, the is deposited on a carrier material is already known.

The object of the invention is to provide an improved catalyst for such an oxychlorination reaction.

The invention therefore relates to a process for the preparation of vinyl chloride monomers, which is characterized in that at elevated temperature an ithan, hydrogen chloride and molecular Oxygen-containing reaction mixture in the vapor phase with a catalyst which is a copper halide

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Halide of an alkali metal or an alkaline earth metal and a compound of rare earths as follows defined, deposited on activated alumina, is brought into contact, the catalyst composition at least 5% by weight of the alkali metal or. Alkaline earth metal Contains in free or in bound (combined) form.

The copper halide in the catalyst composition can either be in the form of the halide as such or in the form a copper compound, e.g. B. copper oxide or copper nitrate, which is converted into the corresponding halide under the reaction conditions. However, it is preferred the use of copper chlorides. Whichever method is used to introduce the copper halide, the catalyst including the carrier preferably contains between 5 and 10% by weight of copper.

The alkali metal or alkaline earth metal halide in the catalyst acts as a promoter. The ratio of alkali metal or alkaline earth metal halide used should be such that the final catalyst composition including the carrier at least 5% by weight of the alkali metal or alkaline earth metal contains. Alkali metals can be sodium, potassium, lithium or cesium and alkaline earth metals are suitable Magnesium or calcium. The catalyst can contain more than one alkali and / or alkaline earth metal in combined form. The preferred alkali metal halide is potassium chloride. The surprising feature of the method according to the invention is that the yields of vinyl chloride and ethylene, based on the fed ethane by increasing the amount of Alkali or alkaline earth metal halide have been improved considerably.

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The third component in the catalyst composition according to the invention is a compound of a rare earth "or a rare earth metal. Under the expression" rare earth "or" rare earth metal "in the description are the metals with atomic numbers between 57 and 71 (inclusive) to understand, for example cerium, lanthanum and neodymium. Technical cerium chloride is preferably used, which is derived from a lanthanide mixture found in Monazite, this having the following approximate composition: La ₂ O ^ = 23%, CeO ₂ = 4-5% , Fr ^ O ^ = 6% Nd ₂ O ^ = 18%, Sm ₂ O? = 3% and other lanthanide oxides = 5%

The function of these rare earth compounds in the catalyst composition is to reduce volatility to reduce the copper content of the catalyst, so that the activity of the catalyst is noticeably increased. The amount the rare earth compound used is advantageously such that it is from 0.2 to 10% by weight of the total catalyst composition including the carrier deliver.

The support material in the form of aluminum oxide is activated ^{by heating to a temperature between 500 °} C. and 1400 ^° C. and preferably between 700 ^° C. and 1200 ^{° C. for at least two hours.} This activation is suitably carried out prior to the deposition of the catalyst components. Such heat treatment reduces the amount of carbon dioxide present in the reaction product and the yield of the desired chlorinated hydrocarbon is substantially increased.

The support can be mixed with the catalyst components directly with a solution of the copper compound, the alkali metal halides and the rare earth compound. Alternatively, the copper compound, the alkali metal halide and the compound of a rare earth element can be impregnated on the carrier sequentially in any order.

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The ethane can be fed into the reaction mixture as any suitable mixture containing ethane fed in ' be e.g. B. in the form of ethane / ethylene mixtures, which are available from technical, Cp-containing gas streams. Since one of the by-products of the reaction of the invention is ethylene, this can be recycled and mixed with fresh feed Ethane to be mixed. The relative proportions of respondents in the gas flow to be fed in can essentially meet the stoichiometric requirements of the Response. During operation, however, it may be desirable to use either an excess of ethane and / or to use oxygen to achieve maximum conversion of the hydrogen chloride to the end product. Of the Oxygen in the gas stream to be injected can be replaced by any suitable molecular oxygen-containing gas such as Air, although it should be noted that the recovery and recycling of the reactants by Use of pure, undiluted, molecular oxygen is facilitated. Diluents such as nitrogen or steam can also be present.

The reaction temperatures may suitably range from 300 ⁰ C to 550 ⁰ C. The contact time varies with the reaction temperature and can be between 0.1 and 20 seconds and preferably between 2 and 10 seconds.

The hydrogen chloride can be supplied from any suitable source, e.g. B. as waste hydrogen from the pyrolysis of 1,2-dichloroethane for the production of vinyl chloride. The hydrogen chloride can also be diluted or partially or completely replaced by chlorine.

The products of the process of the invention include vinyl chloride, Ethylene, ethyl chloride and 1,1- and 1,2-dichloroethanes.

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The latter two substances can be added to vinyl chloride and hydrogen chloride are pyrolyzed. This hydrogen chloride can be recovered and returned to the reaction vessel are recycled for the oxychlorination, as already described above. Ethylene, ethyl chloride and the aforementioned Dichloroethanes can also be returned to the oxychlorination reaction vessel to make additional vinyl chloride to obtain.

The invention is illustrated in more detail by means of the following examples.

example 1

The catalyst was made by impregnating 50 g of aluminum oxide (commercial product Alcoa type F.1, granules with 4 to 10 mesh), which ^{had been heat-treated at 1050 °} C. for 24 hours, with 40 ml of an aqueous solution containing 3s ^ 3 6 copper ( II) chloride hydrate, 7.5 g potassium chloride and 5 * 0 g technical cerium chloride hydrate. The excess water was evaporated, the residue was ^{dried at 150 °} C. for 16 hours. The catalyst therefore contained nominally 6.2% potassium and 2 % copper, based on anhydrous product. A gaseous mixture containing 7% by volume / volume of ithan, 7% by volume / volume of hydrogen chloride, 32.9% by volume / volume of air and 53.1% by volume / volume % Nitrogen was passed over the catalyst at 530.degree. The contact time was 4 seconds. From the ethane feed, 40.1% was converted to vinyl chloride, 38.3% to ethylene and 4.7% to carbon oxides. The total conversion of ethane was 98.1% and 77% of the hydrogen chloride was consumed.

Example 2

The catalyst was the impregnation of 50 g of aluminum oxide (commercial product with the trade name Alcoa type F.1, granules of 4 to 10 mesh), which ^{had been heat-treated at 1050 0} C for 24 hours, with 45 ml of an aqueous

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Solution which contained 6.86 g copper (II) chloride hydrate, 9.0 g potassium chloride and 10.0 g technical cerium chloride hydrate, impregnated. The excess water was evaporated and the residue was ^{dried at 150 °} C. for 16 hours. The catalyst therefore contained nominally 6.6% potassium and 3.6% copper, based on anhydrous product.

A gaseous mixture that contains 7 vol / vol% ethane, 6.8 vol / vol% hydrogen chloride, 33.4 vol / vol% air and 52.8 vol / vol% air .-% nitrogen was passed at 530 ⁰ C over the catalyst. The contact time was 4 seconds. From the ethane feed, 43.5% were converted to vinyl chloride, 39.5 % to ethylene and 4.2% to carbon oxides, the conversion of ithane being 96.5%, while 77% of the hydrogen chloride was consumed.

Example 3

The catalyst was prepared according to the procedure of Example 2, with the exception that 4.19 g of cupric chloride hydrate, 13.5 g of potassium chloride and 6.23 g of technical grade cerium chloride hydrate were used. The catalyst contained nominally 10 % potassium and 2.2% copper, based on anhydrous product.

Containing a gaseous' mixture containing 6.9 vol .- / vol .-% ethane, 6.9 Vol .- / vol .-% of hydrogen chloride, 33.6% air and 52.6% nitrogen was at 530 ⁰ C passed over the catalyst with a contact time of 4 seconds. From the ethane feed, 42.5 % had been converted to vinyl chloride, 36% to ethylene and 4.4% to carbon oxides. The ethane conversion was 99%

Example 4

The catalyst was prepared according to the procedure given in Example 2 with the exception that ^ i? ¹ ? g copper (II) chloride hydrate, 37.1% potassium chloride and 8.55 g technical grade cerium chloride

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were used. The catalyst contained nominally 20% Potassium and 2.2% copper, based on anhydrous product.

Containing a gaseous feed which 7.2 vol .- / vol .-% ethane, 7.1 Vol .- / vol .-% of hydrogen chloride, 33.2% air and 50.5% nitrogen was at 530 ⁰ C and passed a contact time of 4 seconds over the catalyst. From the ethane feed 39-5% was converted to vinyl chloride, 39 ° / ° to ethylene and 3.5% to carbon oxides. The ethane conversion was 98.8%.

Example 5

The catalyst was prepared according to the procedure described in Example 2 with the exception that 333 6 copper (II) · Chloride hydrate, 10.1 g cesium chloride and 5.0 g technical cerium chloride hydrate were used. The catalyst contained nominally 12.1% cesium and 1.93% copper based on anhydrous Product.

A gaseous mixture containing 7.1 vol / vol% ethane, 7 vol / vol% hydrogen chloride, 33.7 vol / vol% air and 52.2 vol / vol % Nitrogen was passed ^{over the catalyst at 530 °} C. with a contact time of 4 seconds. From the ethane feed, 373% were converted to vinyl chloride, -43% to ethylene and 4.8% to carbon oxides. The conversion of ethane was 95%

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Claims (12)

Claims 1.! Process for the preparation of vinyl chloride monomers, thereby / marked that "at elevated temperature a reaction mixture, which Ithane, hydrogen chloride and contains molecular oxygen, in the vapor phase with a catalyst composition which is a copper halide, a halide of an alkali or alkaline earth metal and a compound of a rare earth metal having an atomic number from 57 to 71 (inclusive), deposited on contains activated alumina, is brought into contact, wherein the catalyst composition at least 5 wt .-% of the alkali or alkaline earth metal in a free or bound (combined) form. 2. The method according to claim 1, characterized in that the Copper halide in the catalyst composition copper chloride is. 3. The method according to claim 1, characterized in that the alkali metal used is sodium, potassium, lithium or cesium will. 4. The method according to claim 1, characterized in that as Alkaline earth metal calcium or magnesium is used. 5. The method according to any one of the preceding claims, characterized in that the halide of the alkali or alkaline earth metal is a chloride. 6. The method according to any one of the preceding claims, characterized in that the catalyst composition between 6098 15/1566 0.2 and 10% by weight of the rare earth compound
contains. 7. The method according to any one of the preceding claims, characterized in that the aluminum oxide by at least
two hours of heating between 500 ⁰ C and 1400 ⁰ C before
the deposition of the other catalyst components is activated. 8. The method according to any one of the preceding claims, characterized in that the ethane in the reaction mixture as
Mixture of this is fed with ethylene. 9. The method according to any one of the preceding claims, characterized in that the oxygen feed with steam
or nitrogen is diluted. 10. The method according to any one of the preceding claims, characterized in that the hydrogen chloride partially through
Chlorine is replaced. 11. The method according to any one of the preceding claims, characterized in that the fed reaction mixture with
the catalyst composition at a temperature im
Range from 300 ⁰ C to 500 ⁰ C for a period of time between 0.1 and 20 seconds is brought into contact. 12. The method according to claim 11, characterized in that the fed reaction mixture is brought into contact with the catalyst for between 2 and 10 seconds. $. Vinyl chloride monomer prepared by the process according to one of the preceding claims. 609815/1366