ES2353082T3 - BIOLOGICAL PRODUCTION OF ACETIC ACID FROM RESIDUAL GASES. - Google Patents

Abstract

PROCEDURE AND APPLIANCE TO CONVERT RESIDUAL GASES FROM INDUSTRIAL PROCESSES, SUCH AS PETROLEUM REFINERIES, CARBON BLACK, COQUE, AMMONIA, AND METHANOL PRODUCTION, IN USEFUL PRODUCTS. THE PROCEDURE INCLUDES THE INTRODUCTION OF RESIDUAL GASES IN A BIORREACTOR, WHERE THEY ARE FERMENTED BY CONVIRING THEM IN VARIOUS PRODUCTS, SUCH AS ORGANIC ACIDS, ALCOHOLS H 2, SCP AND SALTS OF ORGANIC ACIDS, BY THE BACTERIES THAT EXIST BODIES. THEN THESE VALUABLE FINAL PRODUCTS ARE RECOVERED, SEPARATED AND PURIFIED.

Description

Biological production of acetic acid from of waste gases.

The general field of the invention is related to procedures, processes, microorganisms and biological devices for the production of products, materials, intermediate products, and the like, such as organic acids, simple cell protein ("SCP"), hydrogen, alcohols and salts of organic acids from waste gas streams of certain industrial processes More in particular, the invention is refers to procedures that use continuous fermentation of gaseous substrate under anaerobic conditions to produce acid acetic acid and its salts, and to microorganisms useful in such procedures

The conventional procedure to produce organic acids, alcohols, hydrogen and salts of organic acids, is the chemical synthesis of the raw materials derived from Petroleum. The rapid escalation of the cost of oil has generated a considerable interest in the production of these valuable goods through fermentation processes that use renewable or residual materials as raw material. The protein Simple cell phone is produced as a byproduct of fermentations, to be used as a supplement for animal feed.

There is also a growing concern about the massive amounts of air pollutants and gases from greenhouse effect produced by industrial processes conventional. The Environmental Protection Agency estimated recently that more than six million metric tons of carbon monoxide and almost four million metric tons of hydrogen, were discharged annually by the industrial complex. A substantial portion of these carbon monoxide and hydrogen residual, is the result of the manufacture of carbon black and of coke production, approximately 2.6 million tons CO metrics and 0.5 million metric tons of H2. Large amounts of carbon monoxide or hydrogen are also produced by the ammonia industry (125, 144 tons CO metrics in 1991), oil refining (8 tons metric per thousand barrels), that of steel laminates (about 69 kg for each metric ton of steel produced), that of the wood kraft process (about 130 kg per ton of pulp). In 1991, the adipic acid industry generated 40,773 metric tons of carbon monoxide that was burned as fuel of value or that burned. In many cases, these gases are discharged directly into the atmosphere, placing a heavy load of pollution in the environment.

Typically, waste gases from the manufacture of industrial products, are released under pressure and low temperatures. Current technology cannot use these diluted gases under such conditions. Adapt technology existing to separate and recover hydrogen or monoxide from carbon from these residual currents, it would be expensive and little practical.

In view of the foregoing, there is a need for a method, a microorganism and an apparatus that are practical and inexpensive for the use of the waste gases described above and for the production of products, materials, intermediates and the like. , such as organic acids, alcohols, hydrogen and salts of organic acids by processes other than chemical synthesis of raw materials derived from
Petroleum.

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Summary of the invention

In accordance with the present invention, it is produced acetic acid from residual carbon monoxide, from hydrogen and / or carbon dioxide from industrial processes, thereby reducing environmental pollution while at At the same time energy and chemical raw materials are saved.

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The present invention provides, in a aspect, a process for the production of acetic acid, which understands:

(to)

supply a continuous flow of gas which includes:

(i)

a gas comprising carbon monoxide;

(ii)

a gas comprising carbon monoxide e hydrogen, or

(iii)

a gas comprising hydrogen and dioxide of carbon;

quad

to a bio-reactor containing an aqueous nutrient medium and the anaerobic bacteria C. ljungdahlii ERI-2, ATCC no. 55380;

(b)

direct a flow of said medium aqueous nutrient to the bio-reactor, and

(C)

ferment said gas and said medium nutrient using the aforementioned bacteria at a low pH, low conditions that allow converting the gas into said acetic acid into a fluid medium

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Acetic acid is recovered from the phase aqueous in a container, or in several separate containers, using a proper recovery process. Process Examples Recovery include extraction, distillation or a combination of them, or other effective recovery processes. The bacteria are extracted from the aqueous phase and are recycled to avoid toxicity and maintain high cell concentrations, optimizing  thus the reaction rates. The cell separation, if desired, is performed by centrifugation, membranous ultrafiltration, or Other techniques

The invention also provides, according to an alternative aspect, a biologically pure culture of the Clostridium ljungdahlii ERI-2 microorganism [ATCC no. 55380].

The main object of the present invention it consists in the provision of a process and / or a microorganism to the production of acetic acid and its salts from monoxide of carbon, hydrogen and / or carbon dioxide. Another object of the The present invention consists in the provision of procedures, microorganisms and apparatus for the production of acetic acid and its salts from the process waste gas stream industrial such as oil refining, the production of Carbon black, coke, ammonia and methanol.

Still an additional object of the present invention consists in the provision of a method for the acetic acid production from a gas stream residual of identical composition to that found in manufacturing Carbon black

Still an additional and more particular object of The present invention consists in the provision of a method, a microorganism and an apparatus that include continuous fermentation of gaseous substrate under anaerobic conditions to lead to perform the conversion of waste gas streams of certain industrial processes in useful products, in particular acid Acetic and its salts.

Other objects and additional scope of the Applicability of the present invention will be revealed to from the detailed description that follows, taken together with the accompanying drawings, in which the same parts have been designated with the same reference numbers.

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Brief description of the drawings

Figure 1 is a schematic diagram of a process for the production of acetic acid from gas residual;

Figure 2 is a schematic diagram of a process for the production of CMA from waste gas;

Figure 3 is a schematic representation of a continuous fermentation system according to a embodiment of the present invention;

Figure 4 is a graphic illustration of the cellular concentration (OD) over time;

Figure 5 is a graphic representation of the acetic acid (HAC) with respect to time.

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Detailed description of the invention

The expression "waste gas" or "stream of waste gas ", as used herein descriptive, means mixed carbon monoxide and hydrogen with other elements or compounds, including carbon dioxide, nitrogen and methane, in a gaseous state, and which are typically released or expelled into the atmosphere either directly or through combustion. Normally, the release takes place under Standard chimney temperatures and pressures. Consequently, the processes of the present invention are suitable for converting those atmospheric contaminants in useful products, especially acid acetic plus salts, such as calcium magnesium acetate (CMA) and potassium acetate (KA).

Anaerobic bacteria that are known to convert carbon monoxide and water, or hydrogen and carbon dioxide, into alcohols and acids and acid salts, include Acetobacterium kivui, A. woodii, Clostridium aceticum, Butyribacterium methylotrophicum, C. acetobutylicum, C. formoaceticum, C. kluyveri, C. thermoaceticum, C. thermocellum, C. thermohydrosulfuricum, C. thermosaccharolyticum, Eubacterium limosum, C. ljungdahlii PETC, and Peptostreptococcus productus . Anaerobic bacteria known to produce hydrogen from carbon monoxide and water, include Rhodospirillum rubrum and Rhodopseudomonas gelatinosa .

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More specifically, bacterial species such as Acetogenium kivui, Peptostreptococcus productus, Acetobacterium woodii, Clostridium thermoaceticum and Eubacterium limosum , produce acetate by means of the reaction:

one

Many bacteria are also known to produce acetic acid from H 2 and CO 2. These bacterial isolates include A. kivui, P. productus and Acetobacterium sp., Which use homoacetic fermentation by anaerobically oxidizing hydrogen and CO2 according to the equation:

2

Acetobacterium woodii and Acetoanaerobium noterae produce acetate from H 2 and CO 2 according to the previous reaction, but in addition to acetate, A. noterae produces some propionate and butyrate. Another chemolithotrophic bacterium, Clostridium aceticum , produces acetate from CO2 using a glycine decarboxylase vehicle.

Some bacteria, such as A kivui, P. productus and A woodii , produce acetate from either CO and H 2 O or either H 2 and CO 2. P. productus provides particularly fast conversion rates, and demonstrates a high tolerance to CO; however, this organism shows a preference to follow Equation (1) greater than for Equation (2).

In addition to these related bacteria, two strains of an additional clostridia that produce acetic acid or ethanol have been isolated from CO and H 2 O or from H 2 and CO 2. One is an anaerobic Clostridium ljungdahlii ERI-2 rod-shaped, gram positive, non-thermophilic, which gives superior productions of acetic acid and operates at a low pH, which greatly increases the recovery of the product. C. ljungdahlii ERI-2 carries out a vigorous acetogenic fermentation of glucose. It also forms spores infrequently and conducts mainly acetogenic fermentation of hexose or H2: CO2. It is a mobile with perimeter flagellation. This new strain of C. ljungdahlii , known as ERI-2, was isolated from a natural water source and was deposited on December 8, 1992, before the American Type Culture Collection (ATCC), Rockville, Maryland, access no. . 55380

For the preparation of the products of the In the present invention, "mixed strains" of the  bacteria listed above. Through mixed strains, a culture mixture of two or more anaerobic bacteria is indicated. This mixed strain, when used in the process described in the Present memory, produces acetic acid. Can also be used to produce other organic acids or salts of themselves, alcohols, hydrogen, SCP, etc.

In the development of the present invention, new strains of anaerobic bacteria that execute this conversion with high efficiency have been isolated. Additionally, modifications of the fermentation conditions may result in the production of ethanol instead of acetic acid in some strains. Depending on the microorga-
nism (s) used, the variables that should be considered in the formation of products from waste gases include constituents and nutrient concentrations, the medium, pressure, temperature, gas flow rate, speed of the liquid flow, the reaction pH, the stirring speed (if a Continuous Agitated Tank Reactor is used), the level of inoculation, the maximum substrate concentrations (introduced gas) to avoid inhibition, concentrations product maximums to prevent inhibition.

According to an embodiment example of the present invention and as shown in Figure 1 of the drawings, a first stage of the conversion process consists of the Preparation of the nutrient medium (10) for anaerobic bacteria. The content of the nutrient medium may vary based on the type of Anaerobic used and the desired product. Nutrients are continuously fed to a bio-reactor or fermenter (12), which consists of one or more vessels and / or towers of a type that includes Continuous Agitation (CSTR), that of Cell Immobilized (ICR), Drip Bed (TBR), Column Bubble, Gas Lifting Fermenters, or other type of suitable fermentation reactor. Inside of the bio-reactor (12) resides the crop, either a simple or mixed species of anaerobic bacteria used in the gas conversion process. For the CSTRs, TBRs, Bubble Columns and Gas Lifting Fermenters, these bacteria live dispersed throughout the liquid phase of reactor, but for ICRs, bacteria adhere to a medium of internal packing. This packing medium must provide a maximum surface area, a high speed of mass transfer, low pressure drop, distribution uniform of gas and liquid, and should minimize the jamming, pollution, nesting and grooving of the wall. Examples of such material means are ceramic Berl brackets, Raschig rings or other high packing performance.

Waste gases (14) are introduced from continuous form in the bio-reactor (12). Gas is retained in the bio-reactor (12) for a period of time that optimizes the effectiveness of the process. Exhaust gases (16), which contain inert and unreacted substrate gases, are released below. The effluent (18) liquid is passed to a centrifuge, a hollow fiber membrane, or other device (20) filtration to separate the microorganisms that you drag. These microorganisms (22) are returned to the bio-reactor (12) to maintain a high cell concentration that produces a faster reaction rate fast (cell recycling).

A next stage of the process consists of the separation of the desired product (s) produced biologically from permeate or centrifuged (24). In the embodiment depicted in Figure 1, the permeate or centrifuged (24) is passed to an extraction chamber (26) in the one that contacts a solvent (28). The solvent (28) must have a high distribution coefficient with respect to the product desired end, high recovery factor, low toxicity for humans, low toxicity to bacteria, immiscibility with water, boiling point appropriately high, and not forming any emulsion with the components of the bio-reactor. The solute distribution between the solvent and the aqueous phase, determine the thermodynamic feasibility and the amount of solvent required to extract the final product. Typical solvents include secondary and tertiary amines in a solvent suitable, tributyl phosphate, ethyl acetate, oxide tri-octyl phosphine and related compounds, in a suitable co-solvent, long chain alcohols, hexane, cyclohexane, chloroform and tetrachlorethylene.

Nutrients and phase materials aqueous (30) pass back to the bio-reactor (12) and the solvent / acid / water solution (32) passes to a column (34) of distillation, in which it is heated to a sufficient temperature to separate solvent (28) from acid and water (36). Solvent (28) passes from the distillation column (34), through a cooling chamber (38) to lower the temperature to the optimum temperature for extraction, and then back to the extraction chamber (26) for reuse. The solution (36) of acid and water passes to a final distillation column (40), in which the desired final product (42) is separated from the water and extract. Water (44) is recirculated for the preparation of nutrient

Figure 2 shows a process for calcium magnesium acetate production road anti-ice (CMA) (46), from waste gas (48). The process is identical to the acid process acetic acid of Figure 1 by solvent extraction. That is to say, organisms, nutrients and process conditions are used identical in continuous fermentation, including the vessels of reaction.

Similarly, cell recycling is used by hollow fiber membrane, centrifugation or other device filtration identically in the process. Finally, the acetic acid extraction in an extraction chamber, followed of the acid-free medium recycling.

After extraction, the CMA production process differs considerably from the acetic acid production process of Figure 1. In the CMA process, the solvent (50) containing acetic acid and a small amount of water is sent to a reaction vessel (52) for the production of CMA. The water content of the solvent stream depends on the solvent used for the extraction of acetic acid. Again, solvents such as secondary and tertiary amines can be used in a suitable co-solvent, in tributyl phosphate, ethyl acetate, trioctyl phosphine oxide and related compounds in a suitable co-solvent, long chain alcohols, hexane, cyclohexane, chloroform and tetrachlorethylene, with variable success. The reaction vessel (52) for CMA, is more suitably a Continuous Agitated Tank Reactor (CSTR), although other reactor systems may be employed. A mixture (54) of dolomitic lime and magnesium oxide in water is added to the solvent containing acetic acid and water. The reaction occurs to produce CMA in aqueous solution at, or below, the saturation level.
tion.

The CMA, water and solvent (56), are sent then to a settling device (58), to separate the aqueous and solvent phases. The solvent phase (60) is returned to the extraction chamber for recycling. The CMA / water (62) is sent to drying / granulation to produce a CMA product granulated.

Potassium acetate (KA) can be produced as alternative product replacing caustic potash (or oxide of potassium) by dolomitic lime. Since KA is produced as 50 percent aqueous solution, no drying or drying required granulation.

Thus, in accordance with the present invention, It is now possible to produce acetic acid and acid salts valuable acetic by fermentation of a gaseous substrate, not only reducing the consumption of valuable raw materials, but also removing dangerous air pollutants from waste gas streams from many industries. The processes above to biologically extract these chemicals, They were based on the fermentation of sugars.

In the processes that have been described in what above, it is preferred that the process be carried out at a pressure above 1 atmosphere. Preferably, it is preferred that it be carried out at pressures of up to 30 atmospheres, and more preferably up to 20 atmospheres, and more preferably up to 15 atmospheres

The specific examples that follow have been chosen to illustrate, but not limited to, the present invention. Unless otherwise indicated, all parties and percentages contained in the description and in the claims, They are based on volume.

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Example one

Production of acetic acid from waste gases of carbon black

This example is aimed at a process used to convert the residual gas of a composition that is equivalent to the of evacuation of a carbon black manufacturing furnace, in acetic acid. The waste gas has a composition of around of 13 percent carbon monoxide, 14 percent of hydrogen, and 15 percent carbon dioxide, 58 being percent remaining mainly nitrogen with traces of oxygen and sulfur compounds. Waste gases are produced as result of a partial oxidation of gas or oil with air insufficient to form amorphous carbon, with about 1.2 kg of Carbon monoxide produced per kg of elemental carbon. These waste gases constitute a serious pollution problem atmospheric, and also represent a valuable resource of matter Chemical premium that is currently not being recovered.

In the development of the present process, they were studied two different routes to produce acetic acid from of residual carbon black gases. The direct route converts CO and H 2 O or H 2 and CO 2 directly in acetic acid of according to Equations (1) and (2), respectively. A route indirect includes the conversion of CO and H2O into H2 and CO2 by water vapor change reaction, followed by the production of acetic acid from H 2 and CO 2. Be found that this indirect route constituted less use Technology efficient.

The tested acetogens have been summarized in Table 1. Among these bacteria that produce acetic acid directly from CO, A. kivui and the recently isolated strain, C. ljungdahlii ERI-2, show much higher speeds for the use of both CO and H2. Additional experimentation continued using these two anaerobic bacteria.

There are obvious advantages in terms of bacteria that use carbon monoxide and hydrogen simultaneously. This could lead to more efficient use of waste gases, and to the elimination of a larger amount of air pollutants

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Operation at the Test Bank Level of the Process Described for Produce Acetic Acid

As shown in Figure 3 of the drawings, and according to an embodiment of the present invention, shows a continuous conversion system at the bank level of tests including a New BioFlo IIC fermenter (150) Brunswick Scientific Co., Inc., Edison, NJ. The fermenter (150) It is equipped with a stirring motor, a pH controller, a foam controller, a thermostat, a dissolved oxygen probe,  a nutrient pump, and a 2.5 l culture vessel. The volume Working is variable (1.5 - 2.0 l). Other operational parameters variables include the medium feed rate (speed dilution), gas flow rate (retention time of gas), and stirring (rpm). Ventilated or exhaust gases leave  of the fermenter (150) through a condenser fixed to a lid ventilated, by means of a water collector and an intake port of samples.

The culture broth (152) is recycled through a hollow fiber module (154) of transverse flow through a peristaltic pump (from Cole Parmer). The recycling speed is around 80-100 ml / min. The hollow fiber module (154) has the following characteristics: the surface area is 325 cm 2 (0.35 ft 2), the pore size is 0.2 µm, and the diameter of lumen is 1 mm. The permeate (156) is pumped to a storage tank (158) (feed tank). Culture cells are returned to the fermenter along the line
(155).

An acetic acid extraction system a countercurrent, which includes settler and mixer components  two-stage, includes a first and a second mixer (160) and (162), and a first and second tanks (164) and (166) of sedimentation. The permeate (168) from the reservoir (158) is pumped to the mixer (160) through a controller (170) flow. The solvent (172) is pumped to the mixer (162) from the solvent tank (174) through a controller (176) flow. Both the mixer (160) and the mixer (162) they are equipped with a stirring mechanism to achieve a good mixture of the aqueous phase and the solvent phase. The mixture of both phases of the mixers (160) and (162), takes settlers (164) and (166), respectively. The separation of phase is performed in the settlers.

The aqueous phase (178) from the settler (164), the solvent phase is pumped to the mixer (162) from the settler (164) is pumped to a separator (182), the phase aqueous (184) from the settler (186) is pumped to a refining tank (186), and the solvent phase (188) from the Settler (166) is pumped to the mixer (160). The refined is recycled to the CSTR (150) along a line (190). This line (190) of recycling is partially bled in (192) to remove inhibition factors

The solvent (180) charged with acetic acid is pumped to a distillation bottle (194) through a pre-heater (196). The distillation bottle (194) It is equipped with two thermocouples (196) and (198) to monitor and control the temperature in the liquid phase and in the gas phase. The heating temperature for distillation is set with in order to achieve maximum evaporation of acetic acid. The acetic acid vapors are condensed in a condenser (100) and collected in a jar (102). The damaged solvent (104) is pumped through a cooling coil (106) to the solvent tank (174).

A test-scale operation of the process described as outlined in Figure 3, was manufactured in the laboratory to determine yields Quantitative under optimized conditions. The nutrient mixture fed to the crop was as follows:

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1. 80.0 ml of a salt composed of:

3

2. 1.0 g of yeast extract

3. 1.0 g of tripticase

4. 3.0 ml of PFN metal tracking solution (Pfenning):

300

5. 10.0 ml of B vitamins:

301

6. 0.5 g of cysteine HCl

7. 0.06 CaCl2 .2H2O

8. 2.0 g of NaHCO 3

9. 1.0 ml of Resazurin (0.01%)

10. 920.0 ml of distilled water. For use with A kivui , the nutrient solution was adjusted to a pH of 6.6, while for the new strain, C. ljungdahlii ERI-2, the pH was adjusted to 4.9. The ability to operate at a lower pH is a great advantage in the recovery of acetic acid. The solution was then sprayed for 20 minutes with an atmosphere of 20% CO2 and 80% N, and then anaerobically transferred and autoclaved for 15 minutes.

Numerous experiments were carried out with both Continuous Agitated Reactors (CSTR) and Reactors Immobilized Cells (ICR). The results obtained have been exemplified in the following data.

CSTR Experiments Using Bacterial Strains A. kivui and C. ljungdahlii ERI-2

The test-scale system that operates with CSTR and anaerobic bacteria, C. ljungdahlii ERI-2 and A. kivui , consisted of a New Brunswick BioFlo IIc fermenter, a hollow fiber membrane unit for cell recycling, and extraction and distillation columns. The nutrient mixture was fed to a bio-reactor at a rate of 3.2 cubic meters per minute. The reactor capacity was 2.5 liters, inside which a constant fluid level of 1.5 liters was maintained. The fluid was stirred at variable speeds of up to 1000 revolutions per minute with gas introduced at a speed of approximately 500 cubic centimeters per minute. Optimal retention times were in the range of three minutes. The fed gas varied with its uptake by bacteria, which in turn was a function of cell density.

The liquid from the bio-reactor was passed to the hollow fiber membrane at a speed of 55 to 70 millimeters per minute. From the hollow fiber membrane, permeate was accumulated at a rate of 1.5 millimeters per minute. The analysis of this permeate indicates that the concentration of acetic acid / acetate at this stage is in a range that exceeds 20 grams per liter. Operating at a pH of 4.9, 42 percent of this product was in the form of acid using C. ljungdahlii ERI-2. For A. kivui , acid production was only 1.4 percent. The results of various developments for the two bacteria, including conversion rates and product yields, have been summarized in Tables 2 and 3.

ICR Experiments Using Bacterial Strain C. ljungdahlii ERI-2

An Immobilized Cell Reactor (ICR), consisting of a glass tube 5.08 cm (2 inches) external diameter by 61 cm (24 inches) high, packed with tissue to support the cells, and Enkamat 7020 as a medium of immobilization, it was tested in the process of acetic acid production. With C. ljungdahlii ERI-2 as an acetogenic anaerobe, 100 percent of the carbon monoxide and 79 percent of the hydrogen were converted to a gas retention time of 20 minutes. The acetic acid concentrations in the extracted liquid were approximately 6.0 grams per liter. The results of the ICR studies have been summarized in Table 4.

The ICR has a certain appeal at scale industrial because the energy costs to operate the reactor are significantly reduced. The appropriate selection of packaging materials, solution phases and pressures, can cause a production that approximates that of the CSTR

Acetic Acid Recovery

Several solvents were tested for acetic acid recovery from permeate, having summarized the results in Table 5. Tributyl phosphate was identified as the one that had both a high coefficient of distribution as a high boiling point. The solvent and the permeate from the cell separator, were mixed in a Two stage extraction process. Alternatively, you could Having used an extraction column. The permeate was introduced in a 3 liter bottle in which it was mixed with the arrival solvent. A ratio of 1 part of solvent to 1 part of permeate, behaved well and provided speeds of high recovery The combined fluids were passed from the mixer to a 4 liter settling chamber in which the solvent / acetic acid mixture was separated as a phase Low density, water and nutrients. Times were used retention time of approximately 15 minutes in tanks sedimentation. The lowest density phase was extracted and fed to a distillation bottle. The refined was passed from the first settler to a second mixer where it was contacted again with the solvent, and then removed to a second settling chamber. This allowed a more complete extraction of acetic acid; acid recovery increased from 82 percent to over 96 percent cent using tributyl phosphate. The solvent / acid mixture acetic coming from this settler, was returned to the first mixer while refining water and organic substances It was passed back to the bio-reactor.

The distillation unit was a bottle of 5 liters with a boiling tank. A common distillation column,  with reflux, could have been used for recovery full of acid. Due to the high boiling point of the tributyl phosphate, an almost complete recovery was performed in a single stage. The solvent / acetic acid mixture was heated to 120 ° C, with acetic acid collected on top of a coil of condensation. In this single stage system, they were reached distillation efficiencies of 70 percent.

The mixtures of solvent, and the distribution coefficients of mixtures of Solvents have been summarized in Table 6.

Example 2

Production of acetic acid from waste gases of carbon black at higher pressures

Mass transport in reactions cell phones can be further increased by operating the system to increased pressures The simple batch experiments were carried out with a view to testing the dynamics of this system. Be found that reaction rates increased by linear proportion to pressure, with a corresponding reduction in the effective retention time. Another advantage of operating under pressure increased is that the reactor volume can be also reduced linearly, that is, the operation to a 10 atmosphere pressure (1 x 10 6 N.m -2) requires a reactor with one tenth of the volume of a reactor operating at 1 atmosphere (1 x 10 5 N.m -2). Figures 4 and 5 show the increase in cell density and acid concentration acetic, respectively, with increased pressure. This Acetic acid concentration greatly exceeds typical batch concentrations for a batch reactor at atmospheric pressure.

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Example 3

Production of acetic acid from waste gases of carbon black with surfactants

Mass transport was also increased with the use of surfactants. Table 7 presents the results of the carbon monoxide uptake tests performed on C. ljungdahlii ERI-2 with the pressure of several commercial surfactants. In each case, the control value of 100 (percent) represents the uptake of CO in batch fermentation, and the sample value, the percentage of control in batch fermentation in the presence of the surfactant.

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TABLE 1 Acetogenic bacteria tested for conversion of CO, H 2 and CO 2

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5

6

7

8

TABLE 5 Acid Distribution Coefficient Study Acetic

9

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TABLE 6 Solvent Distribution Coefficients Mixed

10

eleven

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TABLE 7 Co consumption by ERI-2 in presence of surfactants

12

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Example 4

CMA production from waste black gas from carbon

Residual carbon black gas containing about 14 percent of CO, 17 percent of H2 and 4 percent of CO2, as main components in N2, is sprayed in a reactor continuously stirred tank, maintained at 6 atmospheres (6 x 10 5 Nm -2) and 37 ° C, and containing a 55380 tank of ERI-2 ATCC isolated from Clostridium ljungdahlii . Residual gases are produced as a result of the partial oxidation of hydrocarbons with insufficient air to form amorphous carbon, with about 1.2 kg of carbon monoxide produced per kg of elemental carbon. These waste gases constitute a serious air pollution problem and also represent a valuable chemical raw material resource that is not currently being recovered. The gas retention time (defined as the ratio of the reactor volume to the gas flow rate under standard conditions) is maintained at 0.52 minutes. An aqueous liquid medium containing water, base salts, B vitamins, a nitrogen source and a sulfur source is fed to the reactor at a liquid dilution rate (defined as the ratio of the flow rate of liquid to volume from the reactor) of 1.05 h -1. The stirring speed in this reactor is 322 rpm, the temperature is 37 ° C, and the operating pH is 5.03. Under these conditions, the CO conversion was 83 percent, and the H2 conversion was 54 percent. A hollow fiber membrane cell recycling unit is used to maintain a cell concentration of 10.5 g / l inside the reactor. The product stream of diluted acetic acid / acetate from the reactor, containing 13.2 g / l acetic acid / acetate, is sent to a three-stage countercurrent extraction device, where it is extracted with solvent. The ratio of the solvent to the fed product is 1 to 4. The acetic acid in the acetic acid / acetate product stream is 3.7 g / l. The concentration of acetic acid in the solvent leaving the extractor is 16.7 g / l. The extraction water (medium) is sent back to the fermenter as recycled.

Dolomitic lime / MgO is added to acetic acid directly in the solvent phase to form CMA. After the reaction, the saturated CMA solution is sent for drying, and a granulation of 1.15 kg of CMA is formed that contains a Ca 2+ / Mg 2+ molar ratio of 3/7 per kg of acid acetic.

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Example 5

Production of acetic acid from residual black gas of carbon

Residual carbon black gas containing about 14 percent of H2 and 4 percent of CO2 in N2, is sprayed in a 144 l drip bed reactor that operates at 1.58 atmospheres (1.6 x 10 5 Nm -2), at 37 ° C, and containing 55380 tank of ERI-2 ATCC isolated from Clostridium ljungdahlii . A drip bed reactor consists of a column packed with a commercial packing such as Raschig rings or Berl brackets, in which the liquid and gas contact each other due to flow through the column. In the present example, both the liquid and the gas both enter the column from the top simultaneously, although countercurrent flow is also possible (gas entering through the bottom, liquid entering through the upper part). The gas retention time is maintained at 0.46 minutes and the dilution rate of the liquid medium is 0.57 h -1. The liquid medium contains the same components as in Example 1. Stirring in the reactor is provided by the recirculation of the liquid, using a recirculation rate of 60 gpm. The operating pH in the reactor is 5.05. Under these conditions, the conversion of CO is 57 percent, and the conversion of H2 is 58 percent. A hollow fiber unit is used to maintain a cell concentration of 13.6 g / l inside the reactor.

The acetic acid product stream diluted / acetate, containing 6.4 g / l of acid combination acetic acid / acetate and 2 g / l acetic acid, is sent to a column Three-stage countercurrent extraction. The relationship of Solvent with respect to the feed material is 1: 4. Acid Acetic solvent leaving the extractor is 10 g / l. He Water (medium) from the extraction unit is sent from New as recycled to the reactor.

The solvent containing acetic acid is sent to distillation to recover acid and solvent. Be uses a vacuum solvent distillation column and a acetic acid distillation column in the separation. Be It produces frozen acetic acid as the final product.

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Example 6

Production of potassium acetate from waste gas of carbon black

Carbon black waste gas is used of Example 4 to make potassium acetate instead of CMA. All the fermentation and solvent extraction conditions are They keep the same. Caustic potash (potassium oxide) is used for its reaction with acetic acid, to form a solution to 50 percent potassium acetate directly in the phase solvent.

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Example 7

Production of SCP from waste furnace gas from coke

A residual coke oven gas that contains about 6 percent of CO, 2 percent of CO2, a 57 percent of H2, 5 percent of N2 and 27 percent percent of gaseous hydrocarbon, is fed to a reactor of continuously agitated tank with cell recycling as described above in Example 4. The reactor is used to produce a product such as dilute acetic acid or ethanol. Additionally, the cell concentration inside the reactor It is 13.6 g / l. These cells (microorganisms) can be cultured to produce bacterial simple cell protein like animal feed A purge stream from the reactor that contains cells, is sent to a dryer to process protein simple dry cell.

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Example 8

Production of H2 from refinery waste gas

Refinery waste gas containing about 45 percent of CO, 50 percent of H 2 and 5 percent of CH 4, is sprayed on a 1 l CSTR that operates at 50 ° C and a few inches of water pressure, which contains ERIH2 of Bacillus smithii isolate that was deposited on March 18, 1993 in the American Type Culture Collection, Rockville, Maryland, and provided a tank access no. 55404. The medium in the reactor consists of 1.0 g / l of corn mash liquor. The CO present in the waste gas is converted together with the water into CO2 and H2. With a conversion of 90 percent, the outlet gas stream contains 3.2 percent CO, 64.4 percent H2, 28.8 percent CO2 and 3 , 6 percent of CH4. The CO, CO2 and CH4 are extracted from the gas stream by solvent extraction.

That way, you can see that as result of the present invention, a method is provided highly effective improved to convert waste gas into acid acetic or its salts, whereby its main objective, between others, it has been fully fulfilled. It is contemplated, and will be evident for those skilled in the art from the description that antecedent and the accompanying drawings, which can be made modifications and / or changes in the illustrated embodiments without depart from the present invention. Consequently, it is intended expressly that the description above and the drawings that are accompany are only illustrative of the realizations preferred, and that the scope of the present invention be determined with reference to the appended claims.

Claims (25)

1. A procedure to produce acetic acid, which includes:

(to)

provide a continuous flow of gas which includes:

(i)

a gas comprising carbon monoxide;

(ii)

a gas comprising carbon monoxide e hydrogen, or

(iii)

a gas comprising hydrogen and dioxide of carbon;

quad

to a bio-reactor, said bio-reactor containing an aqueous nutrient medium and the anaerobic bacteria C. ljungdahlii ERI-2, ATTC no. 55380;

(b)

direct a flow of said medium aqueous nutrient to said bio-reactor, and

(C)

ferment the said gas and said medium nutrient using the aforementioned bacteria at a low pH, low conditions that allow converting the gas into said acetic acid into a breeding ground.

2. The procedure according to the claim 1, further comprising releasing evacuation gases from said bio-reactor. 3. The procedure according to the claim 1, further comprising separating said bacterium from  said broth. 4. The procedure according to the claim 3, further comprising returning said bacterium extracted, to said bio-reactor. 5. The procedure according to the claim 1, wherein a solvent phase is formed which it contains acetic acid and water, and an aqueous phase that contains nutrients, in an extraction chamber. 6. The procedure according to the claim 5, further comprising separating from said phase of solvent containing solvent, acetic acid and water, a phase aqueous containing nutrients, and passing said aqueous phase that contains nutrients and materials to said bio-reactor 7. The procedure according to the claim 6, further comprising distilling said phase of solvent to separate acetic acid and water from said solvent immiscible in water. 8. The procedure according to the claim 7, further comprising returning said solvent immiscible in water to said extraction chamber. 9. The procedure according to the claim 8, further comprising separating said acetic acid of said water in a final distillation column, and recycle said water in said bio-reactor. 10. The procedure according to anyone of claims 1 to 9, wherein the gas (i) or (ii) contains also carbon dioxide. 11. The procedure according to any of claims 1 to 10, wherein said gas comprises also one or more of nitrogen and methane. 12. The procedure according to any of claims 1 to 11, wherein said gas is produced through an industrial process selected in the group consisting in the manufacture of carbon black, ammonia, methanol or coke or oil refining 13. The procedure according to any of claims 1 to 12, wherein said bio-reactor is a stirred tank reactor in continuous, a microbial cell bio-reactor immobilized, a drip bed bio-reactor, a bubble column bioreactor, or a gas lift bio-reactor. 14. The procedure according to any of claims 1 to 13, wherein said bio-reactor is maintained at a pressure greater than one atmosphere (1 x 10 5 N.m -2). 15. The procedure according to any of claims 1 to 13, wherein said process is performs at a pressure of up to 15 atmospheres (1.5 x 10 6 N.m <2>). 16. The procedure according to the claim 3, wherein said separation is carried out by centrifugation, filtration with hollow fiber membrane, sedimentation or ultrafiltration. 17. The method according to any one of claims 1 to 16, wherein said bio-reactor further comprises another anaerobic acetogenic bacterium chosen in the group consisting of Acetobacterium kivui, A. woodii, Butyribacterium methylotrophicum, Clostridium aceticum, C. acetobutylicum , C. kluyveri, C. ljungdahlii PETC, C. thermoaceticum, C. thermocellum, C. thermohydrosulfuricum, C. thermosaccharolyticum, Eubacterium limosum, and Peptostreptococcus productus . 18. The procedure according to the claim 1, further comprising contacting the acid acetic with dolomitic lime and magnesium oxide, and perform a drying, thereby producing calcium and magnesium acetate. 19. The procedure according to the claim 1, further comprising contacting the acid acetic with caustic potash, thereby producing acetate potassium. 20. The procedure according to any of claims 1 to 19, wherein the pH in the Bio-reactor is 4.9. 21. The procedure according to the claim 1, further comprising:

(d)

continuously extract a portion of said culture broth containing acetic acid from said  bio reactor;

(and)

contacting said broth of extracted culture containing acetic acid, with a solvent immiscible in water that has an affinity for acetic acid, Y

(F)

optionally distill the acid acetic from said solvent.

22. The procedure according to the claim 21, wherein, after step (e) or (f), the acetic acid is contacted with dolomitic lime and oxide magnesium and dries, thereby producing calcium acetate and magnesium. 23. The procedure according to the claim 21, wherein after step (e) or (f), the acid  acetic is contacted with caustic potash, producing with it potassium acetate. 24. The procedure according to any of claims 1 to 23, wherein said bio-reactor also contains a surfactant that increases the consumption of carbon monoxide by said bacterium. 25. A biologically pure culture of the microorganism Clostridium ljungdahlii ERI-2 ATCC no. 55380