DE102012214064A1 - Process for the purification of carbon dioxide-containing process gases from the production of vinyl acetate - Google Patents

Abstract

The invention relates to processes for the purification of carbon dioxide-containing process gases from the production of vinyl acetate after reaction of ethylene with acetic acid and oxygen in heterogeneously catalyzed, continuous gas phase processes, characterized in that a carbon dioxide-containing process gas is passed through one or more CO2 absorbers which are equipped with packing.

Description

The invention relates to processes for the purification of carbon dioxide-containing process gases from the production of vinyl acetate after reaction of ethylene with acetic acid and oxygen in heterogeneously catalyzed continuous gas phase processes.

Vinyl acetate is an important monomer building block for the preparation of polymers such as vinyl acetate homopolymers or vinyl acetate copolymers with ethylene, vinyl chloride, acrylates, maleates, fumarates or vinyl laurate. The preparation of vinyl acetate is conventionally carried out in a fixed bed tubular reactor (or fluidized bed reactor) in an exothermic reaction of ethylene with acetic acid and oxygen in heterogeneously catalyzed continuous gas phase processes. In this case, usually fixed-bed catalysts are used, which generally contain palladium and alkali metal salts on a support material and may additionally be doped with gold, rhodium or cadmium. The reaction is usually carried out at a pressure of 1 to 30 bar and a temperature of 130 ° C to 200 ° C: C ₂ H ₄ + CH ₃ COOH + ½O ₂ → CH ₃ COOCH = CH ₂ + H ₂ O.

In a secondary reaction, ethylene is oxidized to CO ₂ (carbon dioxide): C ₂ H ₄ + 3O ₂ → 2CO ₂ + 2H ₂ O.

The greater the proportion of ethylene that is converted to by-products, the lower the inevitable selectivity of the reaction of ethylene to vinyl acetate. Desirable are thus the highest possible ethylene selectivities.

The gas mixture supplied to the reactor generally contains a molar excess of ethylene. The reaction of ethylene and the other reactants in the reactor is incomplete. The process gas (product gas stream) taken from the reactor essentially contains vinyl acetate, ethylene, acetic acid, water, oxygen and by-products, predominantly carbon dioxide, and the inert nitrogen, argon, methane and ethane. After leaving the reactor, the reaction product vinyl acetate, unreacted acetic acid, water and other condensable fractions are condensed out as far as possible from the product gas stream and fed to the further work-up and purification by distillation up to the isolation of the pure vinyl acetate. The gas stream remaining after separation of vinyl acetate and condensable fractions from the product gas stream is finally returned to the reactor as recycle gas after further purification steps.

Special attention in the purification of the cycle gas is the sufficient discharge of the by-product carbon dioxide. Otherwise, during continuous operation of the process, carbon dioxide accumulates in the recycle gas, which would soon inhibit vinyl acetate formation in the reactor. Therefore, in conventional processes, a part of the circulating gas is branched off prior to recycling in the reactor and fed to the separation of CO ₂ of CO ₂ scrubbing (CO ₂ absorption / desorption) and then reunited with the other cycle gas. Before CO ₂ removal, this part of the circulating gas is usually freed from further vinyl acetate in a column (water scrubber) by adding acetic acid and water.

The circulating gas is a predominant proportion of ethylene, carbon dioxide, ethane, nitrogen and oxygen existing gas mixture. The recycle gas is added before being returned to the fixed bed tube reactor with the reactants acetic acid, ethylene and oxygen and brought to heating temperature with heat steam operated heat exchangers. To compensate for pressure losses, the recycle gas is usually compressed before being returned to the reactor by means of a cycle gas compressor.

Such methods are for example from DE-A1 10 2009 002 666 known. The DE-A 10 2006 038 689 describes processes for the isolation of vinyl acetate from the aforementioned product gas stream, wherein the expelled steam in the CO ₂ desorber is energetically utilized. Also the EP-A1 1760065 describes processes for the isolation of vinyl acetate from the product gas stream, wherein the acetic acid solution obtained in the recycle gas scrubber is recycled in a certain way in the process for vinyl acetate production.

A disadvantage of the previous embodiment for CO ₂ scrubbing is the pressure losses that occur in this case, so that the recycle gas must be compressed to a significant extent before returning to the reactor, disadvantageously, a considerable energy and equipment expense is required. Furthermore, there is a need to increase the ethylene selectivity in the reaction of the reactants in the reactor. The ethylene selectivity indicates the proportion of vinyl acetate formed, based on the total amount of products formed in the reactor from ethylene.

Against this background, the overall task was to make the separation of CO ₂ from the process gases of the vinyl acetate preparation more efficient and to increase the ethylene selectivity.

The object was achieved in that at least one CO ₂ absorber and optionally a CO ₂ desorber and optionally a water scrubber were equipped with packing, ie not provided with sieve plates as usual. It was particularly surprising that impurities or contamination, for example as a result of polymerizations, did not occur in any significant way in this procedure and in any case did not cause any problem in practice. This finding is in contrast to previous experience in the use of packing for the purification of ethylenically unsaturated monomers. Contamination of the systems must be avoided as far as possible in practice, since otherwise there will be losses in the efficiency of the systems, for example in the energy or mass transfer to the packings, and the systems will even have to be shut down when cleaning is due.

The invention relates to processes for the purification of carbon dioxide-containing process gases from the production of vinyl acetate after the reaction of ethylene with acetic acid and oxygen in heterogeneously catalyzed continuous gas phase processes, characterized in that
a carbon dioxide-containing process gas is passed through one or more, preferably through a CO ₂ absorber, which is equipped with packing.

The process gas may be any gas composition of the process according to the invention. The concrete composition and the further properties of a process gas at a certain point of the method are determined by the process conditions according to which the respective process gas was generated and treated. Corresponding details are described below with further details.

As filler, the usual in chemical process technology filler can be used. For example, the filler bodies are based on metallic or ceramic materials or on plastic. Examples of metallic materials are iron, such as steel, in particular stainless steel, copper, brass, aluminum, nickel, monel metals or titanium. Examples of ceramic materials are oxides of the main group metals or semimetals, for example boron, aluminum or silicon, in particular borosilicate glasses or aluminum silicate glasses. Examples of plastics are polyolefins, halogen-substituted polyolefins, polyethersulfones, polyphenylene sulfides or polyaryletherketones.

The packing can be in a variety of forms, such as in hollow cylinder shape, also called rings, saddle or ball shape. Preference is given to Pall rings, Berl saddles, Hiflow rings, Intalox saddles, hedgehogs or in particular Raschig rings.

The largest diameter of a filling body is preferably 25 to 40 mm.

The packing can be used as a packing or packing. In a bed is known to be a variety of random packing in loose and disorderly stratification on support elements, such as perforated Trageroste or other support floors or grates. If several support elements are used, several layers of packing can be installed (laminations). Packings have a regularly shaped structure, such as tissue or sheet metal packings, in particular thin, corrugated or perforated plates or nets, for example, metal, plastic, glass or ceramic. The respective process gas flows through the bed or packing as usual.

The CO ₂ absorber may contain one or preferably several packs or one or preferably several laminations. The total number of stratifications and packs in a CO ₂ absorber is preferably from 1 to 4 and more preferably from 2 to 3. The CO ₂ absorber preferably contains the fillers in the form of beds, ie preferably not in the form of packs.

The CO ₂ absorber is preferably in the form of a column. Columns are usually understood by the person skilled in the art to mean cylindrical tubes, which usually consist of steel or alloyed stainless steels, more rarely of glass or plastic, and through which the process gas is passed. The fillers are therefore preferably in a column. The columns can contain common installations. A column has a height of preferably 15 to 30 m, in particular 20 to 25 m. The degree of filling of a column with random packings is preferably 75% to 85%, based on the total volume of the column. A stratification or a pack usually has a height of 4 to 7 m.

The CO ₂ absorber is generally charged with an alkaline medium, in particular an alkaline solution, containing, for example, (alkaline) alkali metal hydroxides or preferably (alkaline earth) alkali metal carbonates, in particular potassium carbonate. The alkaline solution usually contains from 20 to 30% by weight of (alkaline earth) alkali hydroxides, based on the total weight of the alkaline solution.

The process gas to be liberated from carbon dioxide is commonly supplied to the CO ₂ absorber in the region of its bottom. The carbon dioxide-containing process gas is removed in the course of passing the CO ₂ absorber carbon dioxide. Carbon dioxide is bound in the CO ₂ absorber. In this way, the process gas is at least partially freed from carbon dioxide. The thus purified process gas is usually removed at the top of the CO ₂ absorber and finally fed back to the reactor for further conversion to vinyl acetate. Usually, the recycle gas prior to introduction into the reactor with ethylene, acetic acid and / or oxygen is applied and, if necessary, compressed and / or brought to the desired temperature.

The carbon dioxide-containing process gas, which is introduced into the CO ₂ absorber, preferably contains 10 to 20 wt .-%, in particular 13 to 19 wt .-% carbon dioxide, 55 to 70 wt .-%, in particular 60 to 70 wt. % Of ethylene and other conventional amounts of the inert, such as ethane, methane, nitrogen or argon, and optionally other constituents, wherein the data in wt .-% on the total weight of this process gas. The purified process gas leaving the CO ₂ absorber preferably contains ≦ 2.5% by weight, more preferably ≦ 2% by weight, and most preferably ≦ 1.6% by weight, but generally ≥ 0 , 5 wt .-% carbon dioxide and preferably 70 to 95 wt .-% and particularly preferably 75 to 85 wt .-% of ethylene and other conventional amounts of the inert, such as ethane, methane, nitrogen or argon, and optionally other conventional ingredients , Wherein the data in wt .-% on the total weight of the purified, the CO ₂ absorber leaving the process gas relate, In the purification according to the invention therefore in particular carbon dioxide is removed from the process gas.

The pressure of the process gas when entering the CO ₂ absorber is usually 9 to 10 bar. Temperatures of 95 to 100 ° C usually prevail in the CO ₂ absorber.

The pressure loss of the process gas in the course of passing the CO ₂ absorber is preferably ≦ 700 mbar, in particular ≦ 500 mbar, more preferably ≦ 300 mbar, even more preferably ≦ 150 mbar and most preferably ≦ 70 mbar.

The bottom of the CO ₂ absorber, ie an alkaline medium, is usually fed to a CO ₂ desorber. The introduced into the CO ₂ desorber alkaline medium is heated in CO ₂ desorber to 100 to 120 ° C and freed of carbon dioxide. Released carbon dioxide is discharged from the process. At the bottom of the CO ₂ desorber freed from carbon dioxide alkaline medium is removed and returned in the head in the CO ₂ absorber.

In a preferred embodiment, the CO ₂ desorber contains packing. It can find the above-mentioned filler in the above forms and quantities use. The CO ₂ desorber contains the filler preferably in the form of beds, ie preferably not in the form of packages. Otherwise, the CO ₂ desorber is constructed and operated according to the prior art. Alternatively, although less preferred, the CO ₂ desorber may also be conventionally screened.

The pressure loss of the alkaline medium between introduction into the CO ₂ desorber and removal from the CO ₂ desorber is preferably ≦ 150 mbar, more preferably ≦ 100 mbar, even more preferably ≦ 50 mbar, and most preferably ≦ 25 mbar.

In a further preferred embodiment, the water scrubber also contains packing. Again, the above-mentioned filler can be found in the above forms and quantities use. The water scrubber contains the packing preferably in the form of packages, ie preferably not in shape of fillings. Otherwise, the water scrubber is constructed according to the prior art. Alternatively, though less preferably, the water scrubber is conventionally equipped with sieve trays.

The water scrubber is known to be integrated in the cycle before the CO ₂ absorber. The process gas is usually introduced in the area of the sump in the water scrubber. The water scrubber is generally charged with acetic acid and water. As a result, for example, vinyl acetate is washed from the process gas. The thus purified process gas is removed from the head of the water scrubber and introduced into the CO ₂ absorber.

In the following, the process for the preparation of vinyl acetate and the inventive separation of carbon dioxide from a process gas or the cycle gas with further details is described.

In the continuous production of vinyl acetate is preferably carried out in tubular reactors which are charged with a fixed bed catalyst. These catalysts are generally supported catalysts doped with noble metals (salts) and promoters, for example palladium and bentonite spheres doped with gold and potassium salts. The reactor is charged with ethylene, oxygen and acetic acid and the reaction at a pressure of preferably 8 to 12 bar abs. and a temperature of preferably 130 ° C to 200 ° C performed.

The reaction temperature in a fixed bed tubular reactor of preferably 130 ° C to 200 ° C is abs by means of boiling water at a pressure of 1 to 30 bar. set. In this case, steam, the so-called self-steam, with a temperature of 120 ° C to 185 ° C at a pressure of 1 to 10 bar abs., Preferably 2.5 to 5 bar abs. Formed. The product gas leaving the reactor contains essentially vinyl acetate, ethylene, acetic acid, water, oxygen, CO ₂ and the inert nitrogen, argon, methane and ethane.

In general, the gaseous mixture leaving the fixed-bed tubular reactor is passed into a pre-dewatering column and the liquid phase obtained at the bottom of the column, mainly vinyl acetate, acetic acid, ethyl acetate and water, is fed to the crude vinyl acetate collecting vessel. In the downstream azeotropic column is separated into vinyl acetate monomer (VAM) and water as the top product and acetic acid as the bottom product. The acetic acid is passed into the acetic acid saturator and returned to the process. The top product removed VAM is passed through the dewatering column to the pure vinyl acetate and separated there into VAM and acetic acid.

The gaseous mixture taken off at the top of the pre-dewatering column, consisting essentially of ethylene and CO ₂ , is freed from further condensable fractions in the recycle gas scrubber, if possible from all. The circulating gas withdrawn at the head of the cycle gas scrubber is compressed in the recycle gas compressor, to compensate for the pressure losses occurring in the reaction circuit, and recirculated back into the reactor as recycle gas. The pressure level of the circulating gas is preferably 8 to 12 bar abs.

A partial stream of the recycle gas (circulating gas partial stream) is branched off on the suction side or pressure side, preferably the pressure side of the cycle gas compressor and supplied ₂ scrubbing to the invention essentially CO ₂ removal of CO and goes to the CO ₂ removal again on the pressure side back to the compressor. The substream removed from the cycle gas compressor makes up about 8 to 12% by volume of the total cycle gas. Usually, after the branching off and before the CO ₂ scrubbing, the withdrawn partial stream is washed in a column (water scrubber) while supplying water and acetic acid. The liquid bottom product can be collected in the crude vinyl acetate container and separated in the downstream azeotropic column. The gaseous top product of the water scrubber, essentially ethylene and CO ₂ , is fed to the CO ₂ scrubber.

The circulating gas partial flow (head product of the water scrubber) is now in a CO ₂ absorber, also called CO ₂ scrubber out.

The circulating gas partial stream is generally combined after the CO ₂ scrubbing, on the pressure side of the cycle gas compressor, and downstream of the removal point of the partial flow for CO ₂ scrubbing, with the further circulating gas. In general, to compensate for the pressure loss of the circulating gas partial stream by means of ethylene, which from the refinery at a pressure of 15 to 25 bar abs. obtained, brought to a pressure level of preferably 0.5 to 2 bar above the pressure of the circulating gas, and fed to the cycle gas. Preferably, the circulating gas partial stream is supplied with the required amount of ethylene via a jet compressor (ejectors, injectors), preferably a suction nozzle. In a preferred embodiment may also be so be proceeded that the entire ethylene feed, which is supplied to the cycle gas before the reactor, is supplied via the jet compressor.

Surprisingly, a considerable increase in production and energy savings in the recovery and purification of vinyl acetate could be achieved by the inventive use of random packings in place of the sieve trays used in the prior art. The separation of carbon dioxide from the process gas takes place in a more efficient manner. In addition, the ethylene selectivity could be increased, d. H. the selectivity of the desired conversion of ethylene to vinyl acetate.

Advantageously, in the procedure according to the invention, it is also possible to dispense with the addition of defoamers, such as polyalkylene glycols. In contrast, occurs with appropriate use of sieve trays in the CO ₂ absorber or in the CO ₂ desorber or in the water scrubber on a strong foam formation, which leads to an increase in pressure in the columns, which is usually countered by the addition of defoamers to the ethylene pressure and to be able to maintain ethylene selectivity. The use of defoamers is associated with effort and costs.

Surprisingly, in the procedure according to the invention, no significant contamination of the parts of the system charged with packing material occurred - even though such problems usually occur in the processing of ethylenically unsaturated monomers in installations charged with packing materials, which is why a person skilled in the art prior to the use of filling unit-containing system components in the process according to the invention Would refrain. Instead, in the process according to the invention, no appreciable impairment of the mass and energy exchange of the random pack systems occurred during their operation.

The following example and the comparative example serve to further illustrate the invention without restricting the invention in any way:
In a plant according to 1 was ethylene-containing cycle gas in Essigsäuresättiger 1 (AcOH saturator) is charged with acetic acid (AcOH), then oxygen (O ₂ ) is added and passed through a steam heated line 2 the tube reactor 3 fed. The recycle gas leaving the reactor, which contained essentially ethylene, vinyl acetate, acetic acid, carbon dioxide, oxygen and inert, was passed over line 4 the pre-dewatering column 5 fed. In the pre-dewatering column 5 The mixture was separated, the bottom product with essentially VAM, acetic acid and water (H ₂ O) via line 19 the crude vinyl acetate container 21 was fed, and after transfer via line 22 in the azeotrope column 23 was separated into a VAM fraction and an acetic acid fraction, which were further worked up, respectively, in process steps not shown here.

The top product of the pre-dewatering column 5 was removed and in the downstream recycle gas scrubber 6 freed from gaseous VAM by washing with acetic acid. The gas mixture (circulating gas) was with the cycle gas compressor 7 increased by about 3 bar. The majority of the cycle gas was via line 18 in the Essigsäuresättiger 1 recycled.

A proportion of about 12 vol .-% of the cycle gas was the pressure side of the cycle gas compressor 7 branched off and over line 8th in the water scrubber 9 transferred there and, to remove more vinyl acetate, treated with acetic acid and then water. The water scrubber 9 was equipped according to the specification for Example 1 and Comparative Example 2 below with packing or with sieve plates. The bottom product comprising acetic acid, water and vinyl acetate was passed over line 20 directly into the pre-dewatering column 5 initiated. The top product of the water scrubber 9 was over line 10 in the area of the sump at a rate of 10 tons per hour in the CO ₂ absorption column 11 directed. The CO ₂ absorption column 11 In a conventional manner, it contained a 25% by weight aqueous potassium carbonate solution and was equipped with fillers or with sieve trays, as indicated below. Otherwise, the CO ₂ absorption column 11 operated in a conventional manner.

The bottom of the CO ₂ absorption column 11 contained potassium hydrogen carbonate as usual and was passed over 12 in the head of the CO ₂ desorption column 13 directed. The CO ₂ desorption column 13 was equipped according to the specification for Example 1 and Comparative Example 2 below with packing or with sieve plates. Otherwise, the CO ₂ desorption column 13 operated in a conventional manner. The bottom of the CO ₂ desorption column 13 contained potassium carbonate and was passed over line 14 in the region of the head in the CO ₂ absorption column 11 introduced.

The top product of the CO ₂ absorption column 11 was over the line 16 in the jet cleaner 17 passed there, mixed with ethylene feeder and finally on the Essigsäuresättiger 1 and back to the reactor 3 initiated.

Via wire 15 was CO ₂ from the desorption column 13 away.

The determination of ethylene or carbon dioxide in the respective process gas was carried out by means of a Siemens Ultramats (IR measurement). The determination of oxygen was carried out with a Siemens oximat. The other ingredients were determined by gas chromatography.

Example 1:

In the water scrubber 9 were packing of the type B1-350 (trade name of the company Montz, material steel 1.4539 according to "steel key") in the form of packages installed.

The CO ₂ absorption column 11 as well as the CO ₂ -Desorptionskolonne 13 were in each case with packings of the type Raschig-Superringe 0.7-DC01 (trade name of Raschig, material steel 1.0330 according to "steel key") equipped in the form of beds. Table 1: Description of process gas streams of Example 1: ingredients * water scrubber 9 CO ₂ absorption column 11 Inlet 8 [parts by volume] Inlet 10 [parts by volume] Deduction 16 [parts by volume] CO ₂ 16 15.9 1.5 C ₂ H ₄ 65 64.9 80 C ₂ H ₆ 9 8.9 9.8 AcOH 1.0 0.005 0,004 VAM 0.005 0.001 0.0005 Oh 0.04 0.001 0.0005 N ₂ 3 3 3 Ar 6 6 5.5 *: CO ₂ : carbon dioxide; C ₂ H ₄ : ethylene; C ₂ H ₆ : ethane; AcOH: acetic acid; VAM: vinyl acetate monomer; AcH: acetaldehyde; N ₂ : nitrogen; Ar: Argon.

Comparative Example 2:

The water scrubber 9 as well as the CO ₂ absorption column 11 and the CO ₂ desorption column 13 were each equipped in a conventional manner with sieve plates. Table 2: Description of process gas streams of Comparative Example 2: ingredients * water scrubber 9 CO ₂ absorption column 11 Inlet 8 [parts by volume] Inlet 10 [parts by volume] Deduction 16 [parts by volume] CO ₂ 16 15.9 4 C ₂ H ₄ 65 64.9 75 C ₂ H ₆ 9 9.5 9.8 AcOH 1.0 0.005 0,004 VAM 0.005 0.001 0.0005 Oh 0.04 0.001 0.0005 N ₂ 3 3 4 Ar 6 6 7 *: CO ₂ : carbon dioxide; C ₂ H ₄ : ethylene; C ₂ H ₆ : ethane; AcOH: acetic acid; VAM: vinyl acetate monomer; AcH: acetaldehyde; N ₂ : nitrogen; Ar: Argon. Table 3: Influence of the column internals on the CO ₂ separation in the CO ₂ absorption column 11: example 1 Comparative Example 2 CO ₂ content in the flue 16 [% by volume] 1.5 4 Table 4: Influence of the column internals on the conversion of ethylene in the reactor 3 and the ethylene content in the recycle gas: example 1 Comparative Example 2 C ₂ H ₄ [vol.%] 75 62 S _E [%] ^a) 93 92.5 C ₂ H ₄ consumption number ^b) 0.377 0.379 STY ^c) [g / l × h] 950 920 a) S _E : C ₂ H ₄ selectivity in the reactor 3:
S _E = vinyl acetate [mol%] / (vinyl acetate [mol%] + 0.5 × CO ₂ [mol%]) × 100;
b) C ₂ H ₄ consumption number = mass of ethylene reacted in the reactor 3 / mass of vinyl acetate formed in the reactor 3;
c) STY = space-time yield = vinyl acetate [g] / (catalyst [1] × time [h]).

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102009002666 A1 [0008]
• DE 102006038689 A [0008]
• EP 1760065 A1 [0008]

Claims (10)

A process for the purification of carbon dioxide-containing process gases from the production of vinyl acetate after reaction of ethylene with acetic acid and oxygen in heterogeneously catalyzed continuous gas phase processes, characterized in that a carbon dioxide-containing process gas is passed through one or more CO ₂ absorber equipped with packing are. Process for the purification of process gases containing carbon dioxide according to Claim 1, characterized in that the fillers are in the form of hollow cylinders, saddles or spheres. A process for the purification of process gases containing carbon dioxide according to claim 1 or 2, characterized in that one or more fillers are selected from the group comprising Pall rings, Berl saddle, Hiflow rings, Intalox saddle, hedgehogs and Raschig rings. Process for the purification of process gases containing carbon dioxide according to claim 1 to 3, characterized in that a CO ₂ absorber contains the packing in the form of beds. A process for the purification of process gases containing carbon dioxide according to claim 1 to 4, characterized in that a CO ₂ absorber has the shape of a column and the column is filled to 75% to 85% with packing, based on the total volume of the column. A process for purifying carbon dioxide-containing process gases according to claim 1 to 5, characterized in that the process gas leaving a CO ₂ absorber contains ≤ 2.5 wt .-% carbon dioxide, based on the total weight of the CO ₂ absorber leaving process gas. A process for the purification of process gases containing carbon dioxide according to claim 1 to 6, characterized in that the bottom of a CO ₂ absorber is supplied to one or more CO ₂ desorbers and contain one or more CO ₂ desorber filler. Process for the purification of process gases containing carbon dioxide according to claim 1 to 7, characterized in that one or more CO ₂ desorber contain the packing in the form of beds. Process for the purification of process gases containing carbon dioxide according to claim 1 to 8, characterized in that one or more water scrubbers are integrated in the cycle before a CO ₂ absorber and one or more water scrubbers contain packing. Process for the purification of process gases containing carbon dioxide according to claim 1 to 9, characterized in that one or more water scrubbers contain the packing in the form of packages.

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