DE1806988A1 - Process for the chlorination of hydrocarbons - Google Patents

Description

L \. JUR. DI / L-CHEM. V.'ALTER BE! * # ..

': .JED HOEPPENER * WOV,

I .. ·. J ¹ JR. DIPL-CHEM. H.-J. WOLrP .F ;. JUR. HANS CHR. AX

023FRANKFURTAMMAiN-HUCHST 1806988

ADElGNSWAiSfcM

Our No. 15 154

Stauffer Chemical Company New York, N.Y., V.St.A.

Process for the chlorination of hydrocarbons

The invention relates to the recovery of largely pure and anhydrous hydrogen chloride from the reaction products of or- ^ global substitution chlorination reactions. In particular, the invention relates to an economical and efficient method for carrying out organic substitution chlorination reactions under increased pressure, in which the hydrogen chloride formed is obtained in a largely pure and anhydrous state and therefore for use in hydrogen chloride consuming reactions such as oxychlorination and alcohol hydrochlorination suitable is. A preferred embodiment of the invention relates to a new and highly effective integrated method which consists in a partial chlorination of methyl chloride and a hydrochlorination of methanol, the partial Substantially anhydrous hydrogen chloride derived from chlorination is used in the hydrochlorination reaction. I.

The conventional partial substitution chlorination reactions usually employ reaction conditions and reactors which ensure substantially complete conversion of the chlorine fed into the reaction system. One method of this type is described in U.S. Patent 3,126,419. In this process, an excess of hydrocarbons and / or partially chlorinated hydrocarbons is used, as are customary in the thermal vapor phase reactions for substitution chlorination reactions. The reactor provides a vaporous stream

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of products in which the desired chlorinated hydrocarbons in a mixture with the hydrogen chloride obtained as a by-product and unreacted raw materials, i.e. hydrocarbons and / or partially chlorinated hydrocarbons are present.

Such organic chlorination reactions occurring in the vapor phase are usually carried out with anhydrous feeds because the equipment required for anhydrous reactions and for the subsequent recovery of the products is considerably less expensive in terms of construction, maintenance and operation than the equipment required for reaction systems where water or hydrochloric acid must be tolerated in the liquid phase. In the conventional processes in which organic run Substitutionsohlorierungs reactions are always although anhydrous conditions are used, devices used for the absorption of the wet hydrogen chloride often _t where even systems for stripping hydrogen chloride and downstream for drying, so that the by-product hydrogen chloride in useful and pure form is obtained. These recovery processes permit the recovery and, if desired, recycle of the unreacted feed and optionally one or more of the substitution products at the same time.

Unfortunately, the method of obtaining wet hydrogen chloride is very laborious in terms of equipment, Operation and entertainment. The most important, goal of the present Invention is therefore to overcome and eradicate the after parts and weaknesses that the previous method of extraction of hydrogen chloride in organic substitution chlorine- ration reactions are inherent.

Another object of the invention is a process for the recovery of substantially anhydrous hydrogen chloride in organic substitution-B-chlorination-B reactions. . ■ _._- ·>

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OWGlN INSPECTED

Another object of the invention is to obtain largely anhydrous and purified hydrogen chloride under an elevated pressure from the product stream of an organic substitution-chlorination reaction.

Another aim is an efficient and economical process in which hydrogen chloride is a by-product from ' organic substitution chlorination reactions obtained in an effective manner and in a largely anhydrous and purified state can be used in reactions that consume hydrogen chloride, such as hydrochlorination and oxychlorination " reactions can be reused.

Another object of the invention is an economical, integrated process which enables the partial chlorination of Methyl chloride and the hydrochlorination of methanol. Another goal is an economical method of extraction of hydrogen chloride in an anhydrous and pure state from the product stream of an organic substitution-chlorination reaction in such a way that the conventional wet hydrogen chloride absorption stripping system is avoided. Other objects and advantages of the invention will appear from the description.

These objects are inventively achieved in that an organic Substituierungschlorierungsreaktion is performed by a λ elevated pressure and substantially anhydrous conditions, to obtain a product stream containing the desired chlorinated products in admixture with unreacted raw material and hydrogen chloride as a byproduct. This product stream is then passed to a recovery zone operated at an elevated pressure and a relatively low end temperature to separate a substantially anhydrous hydrogen chloride stream from which a large percentage of the chlorinated materials have been removed. The chlorinated products are then recovered by any suitable method while the substantially anhydrous hydrogen chloride gas is passed into a suitable reaction zone which consumes hydrogen chloride.

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The inventive method, which is the recovery of essentially pure and anhydrous hydrogen chloride from the product stream of organic substitution chlorination reactions is based on a variety of such substitutional " tion reactions and their combination with reactions consuming hydrogen chloride can be used. To such a substitution priority tion reactions include the conversions of chlorine with saturated ones aliphatic hydrocarbons with 1 to 20 carbon atoms, e.g. methane, ethane and propane, and with halogen

Bk · substituted C ..- to CpQ hydrocarbons, for example methyl chloride, methylene chloride and chloroform.

The essentially anhydrous hydrogen chloride gas which contains a small percentage of chlorinated materials and is recovered under increased pressure, can be carried out in an alcohol hydrochlorination process without compression or additional purification, e.g. in the hydrochlorination of methanol or ethanol can be used. It can also be used as a feed to a suitable oxychlorination process. By further purification of the essentially anhydrous hydrogen chloride to remove chlorinated materials becomes this anhydrous, pure hydrogen chloride is useful for use in a variety of processes in which chlorine

Hydrogen is required. This includes the oxychlorination of saturated and unsaturated aliphatic hydrocarbons, their partially halogenated derivatives and aromatic compounds, such as the oxychlorination of ethylene, propylene, butylene, ethylene dichloride, methane, acetylene, benzene, methyl chloride, Ethyl chloride, trichloroethanes and tetrachloroethanes. The essentially Anhydrous, pure hydrogen chloride is also used in the aldehyde-consuming chloromethylation of benzenes substituted by lower alkyl groups, e.g., toluene. Such a chloromethylation is a Priedel Craft's reaction, in which a chioralkyl group in the presence of a high percentage Hydrogen chloride, i.e. strong hydrochloric acid, is introduced into an aromatic ring.

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According to a preferred embodiment of the invention, an alkyl chloride substitution chlorination reaction is carried out under elevated pressure and temperature to obtain desired chlorinated hydrocarbon products and, as a by-product, hydrogen chloride. The substitution dislocation reaction is carried out under a pressure of at least about 0.35 atmospheres, and preferably at least about 3-5 atmospheres. The most preferred pressure range is between about 3 _f 5 and about 14 atm. The product stream from the substitution chlorination reaction is separated in a partial condensation zone operated under elevated pressure and anhydrous conditions to obtain anhydrous hydrogen chloride, a non-condensable waste gas containing only a small percentage of unreacted alkyl chloride. This gaseous material can be passed into an alcohol hydrochlorination zone without further compression, which alcohol hydrochlorination zone can be operated under effective reaction conditions. A particularly preferred combination is an integrated process which comprises the partial chlorination of methyl chloride to form methylene chloride and / or chloroform and the use of the essentially anhydrous hydrogen chloride obtained in this way in a methanol hydrochlorination plant to produce methyl chloride. The methyl chloride formed in the hydrochlorination "reaction is at least partially passed into the partial chlorination reaction.

In the drawing, a preferred embodiment is schematically shown of the method according to the invention explained.

Chlorine vapor from line 10, methyl chloride vapor from line 12 and / or vaporous reflux material containing methyl chloride from line 14 are intimately mixed and passed through line 16 fed into the chlorination reactor 20. The chlorination reactor 20 is operated under increased pressure, e.g. at at least about 0.35 atmospheres. Suitable conditions are established in the chlorination reactor 20 maintained to avoid substitution chlorination of the

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To effect methyl chloride au methylene chloride and / or chloroform. The reaction is preferably carried out thermally, in the absence of a catalyst, at a temperature between about 350 and about 500.degree. The invention is not limited to this particular type of Substitutionsefalorierung, ⁱ but can also be in the presence of a catalyst, be carried out using a photοchemischen initiation or a gamma ray initiation "Both Elüssigphasenals also Gaephasenreaktionen can be applied" Am significant feature, however, "is daring that the chlorination · · = approximately reacting under substantially anhydrous conditions - is performed.

The stream flowing off via line 22 keeps unreacted CIUCl, CHg ⁰¹ O * ⁰¹¹⁰¹ V ^ccl i ^ ¹ * ^{1 as a} by-product of HCl. Gaseous material from Leitimg 22 is introduced at elevated temperature and pressure in the quench tank 30 in which this current is brought into contact with relatively cold Sücklaufmaterial which is sugeführt via line 34., Which Abschreckkolojme 30 is applied in this method ₉ to-the to partially cool the current coming from the reactor and to prevent the dragging along of solid by-products which would otherwise reach the heat exchangers used in the recovery system. Any suitable gas-liquid contact system, e.g. »BiUG multiple sieve plate colomy, can be used for the operation of zone ■ 30 ani, · ■■ / '« ■: adet »

A largely cooled vapor, which is still under increased pressure, is withdrawn via line 38 and fed into a partial condensation zone, which in this embodiment consists of a number of coolers 40, 42 and 44 and gas-liquid separation systems 41, 43 and 45. In this stage of the traversed any methods and devices may be used to effect a partial condensation "According to one embodiment bevorz'igten 40 is used as water rh-.lmittel in the cooler, while in the coolers 42 and 44 'the

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lower temperatures, suitable coolants can be used. The discharge from the gas-liquid separation systems is collected in the storage tank 50. That from the tank 50 over Liquid material withdrawn in line 52 is passed through a suitable dry trap 54 and then split into two streams. A portion of the dried material is returned via line 34 and another portion is returned to the product distillation and via line 56 Cleaning system 60 directed.

In the distillation purification system, crude chlorinated products such as CH ₂ Cl ₂ , CHCl, and CGI- via line 61 from | Unreacted methyl chloride is separated off, which is returned via line 62. If higher yields of chloroform are desired, methylene chloride is also returned to the reactor for further chlorination.

With reference to the partial condensation zone, it should be noted that it is important for the practice of the invention to carry out the partial condensation under elevated pressure which, however, is somewhat lower than the pressure in the chlorination zone. A sufficiently low temperature is used in the last cooler 44. Substantially anhydrous conditions are maintained throughout the partial condensation zone, so that the vapor stream emerging from the separation unit 45 in line 66 consists of substantially anhydrous hydrogen chloride under increased pressure which contains a greater part of the CH., Cl and essentially all of the CH ₂ Cl ₂ , CHCl-, and CCl. no longer contains. In order to obtain a useful feed to a methanol hydrochlorination reactor, the conditions at the exit of the partial condensation zone are preferably adjusted to a pressure between about 3.5 and about 14 atmospheres and a temperature between about -25 and about 0 ° C.

Substantially anhydrous hydrogen chloride mixed with a small percentage of methyl chloride in line 66 is mixed with methanol vapor from line 68 and transferred to a suitable methanol hydrochlorination reactor 70 for recovery

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Lethyl chloride introduced. The hydrochlorination reaction is preferably carried out in the presence of a catalyst. The most preferred catalytic material for the integrated process of the invention is solid activated alumina, although solid or dissolved zinc chloride and other catalysts known to carry out this reaction can also be used. The methanol hydrochlorination is described, for example, in the USA patent 1,834,089 and in the French patent 1,471,895.

From zone 70, a vapor product is obtained via line 72, which consists of methyl chloride, hydrogen chloride and water. This stream is then passed into a recovery system 74 which separates the methyl chloride formed from the water of reaction. The reaction water is removed and fed through 751 together with small amounts of unreacted methyl alcohol, Dimethyl ether and unreacted or excess hydrogen chloride are discarded. The methyl chloride product and excess hydrogen chloride vapors that are saturated with water are withdrawn from the recovery system via line 82 and passed into the drying zone 90. The drying zone preferably consists of a multi-tray column running in countercurrent is sprinkled with concentrated sulfuric acid. Contact with concentrated sulfuric acid also causes dimethyl ether impurities reduced to a minimal amount. The dried stream containing methyl chloride and hydrogen chloride from line 91 is treated in a deep-frozen condenser 92, to separate liquid methyl chloride via line 94. The desired amount of methyl chloride is via line 94 to Use in the chlorination reactor 20 withdrawn. Liquid methyl chloride (crude, technical grade) is also drawn off via line 94 and converted to technically pure in a conventional manner Purified methyl chloride. Vaporous methyl chloride that contains some hydrogen chloride, can be withdrawn via line 91 and sent to a compressor (not shown) which

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then pumps the crude methyl chloride vapors directly to the inlet mixer for steam feed to the chlorination reactor 20 "This Alternative method saves the deep freezing in the low temperature condenser 92 and the subsequent re-evaporation of the raw Methyl chloride, which is returned to the chlorination reactor 20 iso Largely pure hydrogen chloride, which contains a small amount of methyl chloride, is drawn off via line 93 and can further purified to a technically pure product.

It should be noted that the methyl chloride fed to the reactor 20 is in the form of a highly atomized spray jet can be performed, creating a higher ChIοr / Methylchiοrid ratio is made possible in the single reactor system. The methyl chloride can also be used as a highly atomized spray jet in both Reactors of a two-reactor system connected in series are introduced. When a higher yield of chloroform is desired is, methylene chloride and methyl chloride are recycled to one or more reactors. From thermodynamic and economic reasons are both the methylene chloride and the methyl chloride return into the reactor inlet or the Reactor inlets in the form of a highly atomized spray jet introduced, e.g. according to USA patent 3,126,419

The invention is illustrated in more detail in the following examples explained. '

Example 1 ;

The following feed materials are intimately mixed with 16 undiber line in the thermal chlorination reactor 20 introduced: 39.7 kgMolA superheated steam chlorine of 25 ⁰ C, consisting chloride 31.1 kgmol / h of methylene chloride vapor and 116.5 kgMolA return from 84.6 kgMolA methyl, 18.6 kgMolA hydrogen chloride and 12.9 kgMolA methylene chloride. The reactor 20 is operated at an operating pressure of approximately 7.7 atmospheres, and the maximum temperature reached in the reactor is 425 ° C. A reaction is running in the reactor with a residence time of approximately 12 seconds. away. No free or unreacted chlorine is found in the off-gas flowing to the quench column 30. It is a captured in tank 50 liquid flow via line 34 in the upper

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Part of the quench column 30 introduced. The temperature at the bottom of the quench tower 30 is maintained at about 120 ° C, during the flowing out of the top of the column 30 has a steam temperature of about 100 ⁰ C. In the cooler 40, the vaporous material from line 38 is cooled to a temperature of about 40 ° C. by indirect water cooling. A temperature of approximately 10 ° C. is reached in the cooler 42 and of approximately -12 ° C. in the cooler 44 by freezing. The final pressure of the gaseous material at the outlet of cooler 44 is about 7 atmospheres.

The uncondensed material in line 66 has the following Strömungszusammensetzungj mixed 41.0 kgmol / h hydrogen chloride, 6 _S 12 kgmol / h of methylene chloride and 0.0045 kglol / h methylene chloride, the material in line 66 is 32.8 kgmol / h of superheated methanol . The combined vapors are then directed to the Methanol ™ hydrochlorination reactor 70 which contains an activated alumina catalyst. The heat of reaction is removed by a boiling heat transfer fluid contained within the reactor 70 jacket. In this example, the temperature of the reaction stream is reduced by passing it through a conventional heat exchange recovery system 74. The methyl chloride product and excess hydrogen chloride vapors, which are saturated with water, are dried in the multi-tray drying column 90, which is sprinkled with concentrated sulfuric acid in a countercurrent. The dry stream containing methyl chloride and hydrogen chloride is fed into a low-temperature cooler 92, in which methyl chloride is condensed and passed via line 94 to the partial chlorination process. "Non-condensable hydrogen chloride is withdrawn via line 93"

When aiming for maximum formation of methylene chloride is then preferably a low chlorine ratio and a single chlorination reactor 20 used, wherein for the

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BATH

Controlling the reaction temperature the excess methyl chi ο-rid serves as a diluent. If a maximum chloroform / Methylohlorid-ProduktverhältniB desired by substitution chlorination of methyl chloride "then can be applied in series two reaction zones, as described in USA. Patent 3,126,419. A diluent such as carbon tetrachloride or perchlorethylene can be used when more highly chlorinated products are desired in a one or two reactor system.

The hydrogen chloride formed product, the position in the manufacturing Λ is obtained from chloroform or carbon tetrachloride during the substitution chlorination of methyl chloride can be produced by one of the following, preferred methods recovered controlled or removed "

1.) Hydrogen chloride can be obtained as gaseous, anhydrous HCl from the partial chlorination system, for example via line 66 in the drawing. If liquid HCl is desired, a compressor is arranged at the product outlet of the partial chlorination system, for example between cooler 44 and separation system 45, which compresses the HCl / CH ^ Cl vapors to at least about 10.5 atmospheres. This gas is then cooled and fed to a fractionation column which, under the action of a refrigerated reflux condenser, dispenses liquid HCl under at least about 10.5 atm returns to the fractionating column. The fractionation column is therefore able (with sufficient sieve troughs above the feed point) to deliver essentially pure HCl overhead. By placing sufficient troughs below the feed point, the fractionation column can produce a bottom product of essentially pure CHnCl which can be recycled to the partial chlorination process at a suitable point, for example at 60 or 62.

2.J By attaching a frozen CCl ^ - (or CgCl ^ -Jfcbsorptionssytees at the outlet of the extraction system (line 66) of the par * - It is also possible to use high-quality tialeblorination oil Hydrogen chloride off-gas from the partial chlorination plant

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The 001 ₄ - (ο4 · γ C ₂ Cl ₄ - ) ltro «aut the AfctorpUontkoXonne, * · ^Γ ΟΗ, ΟΙ and ttwat contains HCl , is then given to the Mthrfachbödtn separating column, where HCl and CH, Cl alt top product tnttrnt and sum of the chlorination reactor can be returned. line to COl. (or C ₂ Cl ₄ ) tohwaont flow is water-cooled, then titanium-cooled and refilled in the absorber.

3) Hydrogen chloride, which is obtained in the production of chloroform and carbon dioxide in the partial chlorination process, can be used in the methanol hydrochlorination process to form excess methyl chloride, whereby the total production of HCl is kept in equilibrium. 4.) Hydrogen chloride, which is produced in the production of chloroform or carbon tetrachloride during the partial chlorination process, can be allowed to flow through the methanol hydrochlorination plant without reaction. It can then be removed as follows:

a) by compression and fractionation as described above under 1). In this case, the compressor and the fractionation column are located in the recovery system for the methanol hydrochlorination behind the sulfuric acid drying column 90

b) Through a deep-frozen CCl. or CgCl. wash, which in this Fall in the recovery system of methanol hydrochlorination in connection is arranged on the sulfuric acid drying column 90.

In all of these cases, the separation of hydrogen chloride takes place in high quality and under anhydrous conditions. Example 2 t

The feed materials and equipment up to line 66 are the same as described in Example 1. The material in line 66 is mixed with methane and air or oxygen. These combined vapors are then introduced into a methane oxychlorination heating system as described in British Patent 587,969 to obtain additional methylene chloride, chloroform and carbon tetrachloride from the by-product HCl "

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Example j :

The feed materials for this example are the same as for example 1. The equipment and the process steps are also the same up to line 66. At this point, the uncondensed material with the composition: 41.0 kg mol / h hydrogen chloride, 6 , 12 kgMol / h of methyl chloride and 0.0045 kgMol / h of methylene chloride are added to a compressor which compresses the mixture to 10.5 atmospheres. This gas is then cooled and fed into a fractionation column. A deep-frozen reflux condenser returns liquid HCl to the top (of the column. An overhead stream, which consists of essentially anhydrous, pure hydrogen chloride in an amount of 40.6 kgmol / h HCl and 0.004 kgmol / h CH, Cl, is discharged from the fractionating column This overhead stream of essentially pure, anhydrous hydrogen chloride is intimately mixed with ethylene and air or oxygen and introduced into an ethylene oxychlorination reaction system as described in Canadian Patent 517 009. The withdrawn from the bottom of the fractionation column and extracted from 0.4 kgmol / h HCl, 6.0 kgmol / h CH ^ Cl and 0.0045 kgmol / h CHpCl ₂ existing St ^ rom is returned via line into the Partialchlorierungsverfahren. example A i

The feed materials for this example are the same Chen as for Example 1. The equipment and process steps are also the same up to line 66. At this Place the uncondensed; e material of the composition: 41.0 kgmol / h of hydrogen chloride, 6.12 kgmol / h of methyl chloride and 0.0045 kgMol / h of methylene chloride are added to a compressor which compresses the mixture to 10.5 atmospheres. This gas then becomes cooled and placed on a fractionating column, a frozen one A flow cooler returns liquid HCl to the top of the column. An overhead product from 40.6 kgMol / h HCl and 0.004 kgKol / H OH-jGl is subtracted from the preparation colomis and mi "j A'thane and air or oxygen Lnni ^ mixed and in one

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- 14 -: "■ ■

Ethane oxychlorination reaction system introduced, which mainly Ethyl chloride and dichloroethanes are produced as it is in the British U.S. Patent 938,096. By changing the This process produces trichlorethylene with a CpHg / HCl ratio and perchlorethylene in varying amounts »

Example 5 i .-'-.-:., -. ; ■■

The feed materials for this example are the same as for example 1. The equipment and the. Procedure st u- ' Fences are also the same up to line 66

fe place becomes the uncondensed material of the composition *; Added 41.0 kgmol / h of hydrogen chloride, 6.12 kgmol / h of methylene chloride and 0.045 kgmol / h of methylene chloride to a compressor which compresses the mixture to 10.5 atm. This gas is then fed, cooled, to a fractionation column. A deep-frozen reflux condenser returns liquid HCl to the top of the column. An overhead product of 40.6 kgMol / h HCl and 0.004 kgMol / n ClHLCl is withdrawn from the fractionating column and intimately mixed with ethylene dichloride and air or oxygen and introduced into an ethylene oxychlorination reaction system to form trichlorethylene and perchlorethylene, as is the case, for example, for a two-stage process Reactor is described in British Patent 904,405. Example 6 :

P The feed materials for this example are the same as for Example 1. The equipment and process steps up to line 66 are also the same. At this point the unfused material of the composition is 41.0 kgmol / h of hydrogen chloride, optionally 6.12 kgmol / h of methylene chloride and 0.0045 kgmol / h of methylene chloride to a compressor, which compresses the mixture to 10.5 atm ₀ This gas is then cooled to a fractionating given Sin frozen reflux condenser performs a liquid HCl reflux to the top of the column-r an overhead from 40.6 krMol / L HCl and 0.004 kgmol / h CH ₃ Cl is withdrawn from the fractionation column, intimately mixed with Benzene and air b or oxygen mixed and in a benzene oxychlorination reaction system according to the Raschig (Prahl) process, such as

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■ ι ;;! Ϋ | ιι - «; ι.; Ι -: - J! Ll !! l |||| I;,. ■■! (.Ι., Τίΐ'ρι;;., - _(i

·· t »British Patent 362 817 or in Chi« · and Mtt. Ingr · Hr. lit «eiten 770-775 (1940) described Ut ₁ introduced. Below the filter, chlorine suspension is used and the formation of only small amounts of polyhydric sol as a by-product is mainly monochlorobenzene. Example J t

The raw materials used for this example are the same as for example 1. The equipment and the process stages are also the same up to line 66. At this point, the non-condensed material of the composition! 41.0 λ kghol / n hydrogen chloride, 6.12 kfMolA methyl chloride and 0.0045 kgMol / h methylene chloride are added to a compressor which compresses the mixture to 10.5 atU. This gas is then cooled and fed to a fractionation column. A deep-frozen reflux condenser leads a liquid HCl backflow to the top of the column. An overhead product of 40.6 kgMol / b. HCl and 0.004 kg mol / l CH ^ Cl are withdrawn from the fractionating column and intimately mixed with acetylene and air or oxygen to be introduced into an acetylene oxychlorination reaction system as described in British Patent 1,090,783. The reaction products are dichloroethylene, trichlorethylene and some higher chlorinated ethylene or ethanes. Vapor and inert gases can be introduced together \ with the raw batch in such Acetylenoxychlorierungsverfahren to improve by maintaining optimum reaction temperature the yield. Example 8 ;

The feed materials for this example are the same as for Example 1. The equipment and process steps up to line 66 are also the same. At this point , the uncondensed material of the composition: 41.0 kgmol / n hydrogen chloride, 6.12 kgMolA methyl chloride and 0.0045 kgMolA methylene chloride is placed on a compressor which compresses the mixture to 10.5 atmospheres. This gas is then cooled and fed to a fractionation column. A deep-frozen reflux condenser

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returns a liquid HCl reflux to the top of the column. An overhead product of 40.6 kgMol / h HCl and 0.04 kgMol / h CHnCl is withdrawn from the fractionating column ^ thoroughly mixed with ethylene and introduced into a liquid or vapor phase hydro-chlorination reactor which contains an active catalyst to convert ethyl chloride A typical liquid phase ethyl chloride process is described in Canadian Patent 448,020.
Example 9 :

The feed materials for this example are the same as for Example I ₀ equipment and process steps up to line 66 are also the same. At this point, the uncondensed material is the composition? 41.0 kgMol / h of hydrogen chloride, 6.12 kgMol / h of methyl chloride and 0.0045 kgMol / h of methylene chloride are added to a compressor which compresses the mixture to 10.5 atmospheres o This gas is then cooled and fed to a fractionation column = one deep-frozen reflux condenser returns a liquid HCl reflux to the top of the column. An overhead product stream of 40.6 kg mol / h HCl and 0.004 kg mol / h CH ^ Cl is withdrawn from the fractionation column and introduced into a chloromethylation reactor which contains toluene and pa-ra-formaldehyde in the presence of zinc chloride, as described in Bull »Soc. chimc, 1923, Jii, 313. In this reaction, the chloromethyl group is introduced into the toluene ring in high yield, it being possible for the reaction to be carried out either batchwise or continuously.
Example 10 :

This example explains the invention for the case that in the a partial chlorination of methane takes place in the first zone and the hydrogen chloride consuming zone a methane oxychlorination reaction zone is.

The following feed materials are intimately mixed and introduced via line 16 into the reactor 20: 20.2 kgmol / h of superheated steam chlorine of 25 ⁰ C, 8.41 kgmol / h methane and a recycle stream of 17.0 kgmol / h methane, 2, 82 kgMol / h inert gases

^ - ^ q § a S 0/1 7 4 2

■ and 0.095 kgMolA CH ₂ Cl ₂ . The reactor 20 consists of two series-connected thermal chlorination reactors ₀ The reactor 20 is driven atmospheres at an operating pressure of about 2.8 and held the maximum reactor temperature at 425 ° C. A reaction takes place in the reactor with a residence time of about 12 seas. away. No free or unconverted chlorine is found in the exhaust gas flowing to the quenching column 30. A liquid stream collected in tank 50 is passed via line 34 into the upper part of the quenching column 30. The temperature in the bottom of the quenching column 30 is about 120.degree. C., while the steam flowing out of the head of the quenching column has a temperature of about 100.degree. The steam material from line 38 is cooled to about 40 ° C. by indirect water cooling in the cooler 40, while a temperature of about 10 ° C. is reached in the cooler 42 and of about -25 ° C. in the cooler 44 »At the outlet of the cooler 44 if the gaseous material is under a pressure of about 2.6 atmospheres

The uncondensed material in line 66 has the following flow composition: 20.35 kgmol / h hydrogen chloride, 8.60 kgmol / h methyl chloride, 0.095 kgmol / h methylene chloride, 2.85 kgmol / h inert gases and 17.15 kgmol / h methane. This material is mixed with 12.95 kgmol / h of chlorine. These combined vapors are then introduced into a Methanoxychlorierungs reactor, similar to the favorable under maximum for the formation amounts of methylene chloride conditions is operated.

In terms of equipment and running costs, it is more economical to purify HCl under anhydrous conditions rather than an absorption stripping method with water or weak Use acid to remove unreacted hydrocarbons or chlorinated hydrocarbons, as in the preceding Examples is described.

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Claims (1)

Claims 1.) Integrated process for the extraction of pure and anhydrous Hydrogen chloride as a by-product in organic substitution chlorination reactions and using this hydrogen chloride in hydrogen chloride consuming reactions, thereby characterized in that an organic, thermal substitution chlorination is carried out in the vapor phase in a first zone and thereby a vaporous product stream of chlorine-substituted materials and hydrogen chloride is obtained, whereby one this reaction is carried out in the first zone under largely anhydrous conditions and increased pressure, whereupon this Withdraws product stream and introduces it to a recovery zone chlorine-substituted materials from a gaseous stream containing essentially anhydrous hydrogen chloride under increased conditions Separate pressure and the stream containing hydrogen chloride as a feed to a hydrogen chloride consuming Introduce reaction zone. 2o) Method according to claim 1, characterized in that the Substitution Schlorierung is carried out in the first zone on an alkane or an alkyl chloride and the product stream from this zone is introduced into a partial condensation zone operated under increased pressure and lower final temperature To condense chlorine-substituted materials while the essentially anhydrous hydrogen chloride remains gaseous, whereupon the stream containing the hydrogen chloride without any further Purification is introduced into a reaction zone consuming hydrogen chloride. 3.) Process according to claim 2, characterized in that the first zone is an alkane or an alkyl chloride partial chlorination zone and the reaction zone consuming hydrogen chloride is a hydrochlorination zone for the alcohol containing the corresponding alkyl radical. _{0 ,; i} ... 909850/1742 4.) Procedure according to. Claim. 2, characterized in that the Alkyl chloride is methyl chloride and the alcohol is methanol. 5.) Method according to claim. 2, characterized in that the Hydrogen chloride consuming reaction zone an oxy-clarification zone is for a compound having the same carbon number as the alkane or alkyl chloride used in the first zone Has" 6c.) Method according to claim 5 »characterized in that this Alkane is methane. ^ 7 ») Method according to claim 5, characterized in that the Allyl chloride is methyl chloride. 8.) The method according to claim 2, characterized in that this partial condensation zone is operated at a pressure between about 3 »5 and about 14 atü and at a temperature between about -25 and about 0 ^° C. 9.) Process according to claim 1, characterized in that the reaction consuming hydrogen chloride is a chlorination reaction is. 10.) The method according to claim 91, characterized in that the first zone is a methyl chloride partial chlorination zone. 11.) Process according to claim ID, characterized in that the ™ hydrochloric consuming reaction is a Äthylenoxychlorierungsreaktion ₀ 12.) The method according to claim 3Ö, characterized in that the Hydrogen chloride-consuming reaction is ethane oxychlorination ο 13ο) Process according to claim Iß, characterized in that the reaction consuming hydrogen chloride is an ethylene dichloride-oxychlorination reaction. 9098 50/174 2 "to" 14 ·) Method according to claim 3Q, characterized in that the The reaction which consumes hydrogen chloride is benzene oxychlorination. . . 15ο) The method according to claim 3Q, characterized in that - that the Hydrogen chloride-consuming reaction is acetylene oxychlorination is" 16β) method naoh claim 10, characterized in that the Hydrogen chloride consuming reaction an ethanol hydrochlorination reaction is. - 17 °) Method naoh claim 10, characterized in that this hydrogen chloride consuming reaction the _; Is chloromethylation of toluene. ; 18.) Method naoh claim 1, characterized in that the withdrawn from this recovery zone, essentially anhydrous, gaseous hydrogen chloride is compressed, cooled and then fractionated to remove other chlorinated materials from the / essentially to separate anhydrous pure hydrogen chloride, For: Stauffer Chemical Company Lawyer 909850/1 7 42