WO2011144823A1 - Absorbent solution containing a thiadiazole-derivative degradation inhibitor and its use in an absorption process - Google Patents

Absorbent solution containing a thiadiazole-derivative degradation inhibitor and its use in an absorption process Download PDF

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Publication number
WO2011144823A1
WO2011144823A1 PCT/FR2011/000275 FR2011000275W WO2011144823A1 WO 2011144823 A1 WO2011144823 A1 WO 2011144823A1 FR 2011000275 W FR2011000275 W FR 2011000275W WO 2011144823 A1 WO2011144823 A1 WO 2011144823A1
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Prior art keywords
thiadiazole
degradation
thiol
amino
salt
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PCT/FR2011/000275
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French (fr)
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Bruno Delfort
Pierre-Louis Carrette
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IFP Energies Nouvelles
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/14—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by absorption
    • B01D53/1456—Removing acid components
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/14—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by absorption
    • B01D53/1493—Selection of liquid materials for use as absorbents
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2252/00—Absorbents, i.e. solvents and liquid materials for gas absorption
    • B01D2252/20—Organic absorbents
    • B01D2252/204—Amines
    • B01D2252/20415—Tri- or polyamines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2252/00—Absorbents, i.e. solvents and liquid materials for gas absorption
    • B01D2252/20—Organic absorbents
    • B01D2252/204—Amines
    • B01D2252/20436—Cyclic amines
    • B01D2252/20447—Cyclic amines containing a piperazine-ring
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2252/00—Absorbents, i.e. solvents and liquid materials for gas absorption
    • B01D2252/20—Organic absorbents
    • B01D2252/204—Amines
    • B01D2252/20478—Alkanolamines
    • B01D2252/20484—Alkanolamines with one hydroxyl group
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2252/00—Absorbents, i.e. solvents and liquid materials for gas absorption
    • B01D2252/20—Organic absorbents
    • B01D2252/204—Amines
    • B01D2252/20478—Alkanolamines
    • B01D2252/20489—Alkanolamines with two or more hydroxyl groups
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2252/00—Absorbents, i.e. solvents and liquid materials for gas absorption
    • B01D2252/60—Additives
    • B01D2252/604—Stabilisers or agents inhibiting degradation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
    • B01D2257/30—Sulfur compounds
    • B01D2257/302—Sulfur oxides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
    • B01D2257/30—Sulfur compounds
    • B01D2257/304—Hydrogen sulfide
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
    • B01D2257/30—Sulfur compounds
    • B01D2257/306—Organic sulfur compounds, e.g. mercaptans
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
    • B01D2257/30—Sulfur compounds
    • B01D2257/308—Carbonoxysulfide COS
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
    • B01D2257/50—Carbon oxides
    • B01D2257/504—Carbon dioxide
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2258/00—Sources of waste gases
    • B01D2258/02—Other waste gases
    • B01D2258/0283—Flue gases
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02C—CAPTURE, STORAGE, SEQUESTRATION OR DISPOSAL OF GREENHOUSE GASES [GHG]
    • Y02C20/00—Capture or disposal of greenhouse gases
    • Y02C20/40—Capture or disposal of greenhouse gases of CO2

Definitions

  • the present invention relates to the field of the deacidification of a gaseous effluent. More specifically, the present invention provides compounds for reducing the degradation of an absorbent solution implemented to absorb the acidic compounds contained in a gaseous effluent, the absorbent solution comprising amines in aqueous solution. In particular, the invention relates to compounds used to reduce the degradation of amines used for the deacidification of oxygen-containing gases, such as for example combustion fumes.
  • the deacidification of gaseous effluents is generally carried out by washing with an absorbent solution.
  • the absorbent solution makes it possible to absorb the acid compounds present in the gaseous effluent (H 2 S, mercaptans, CO 2 , COS, SO 2 , CS 2 ).
  • the amines can be degraded by the oxygen generating a consumption of the amine and the formation of degradation products which accumulate in the unit or, for the most volatile, which are entrained in the gaseous effluents of the process.
  • MAA monoethanolamine
  • the degradation phenomena of the absorbent solution amines are increased by the presence of a massive amount of oxygen in the feed to be treated up to 5% by volume in general.
  • the volume content of oxygen in the fumes can reach 15%.
  • the degradation of the absorbing solution therefore penalizes the performance and the proper functioning of the gas deacidification units.
  • degradation inhibiting additives consist according to their nature in a reduction-type reaction and / or in a capture, trapping and / or stabilization of the radicals formed in the absorbent solution in order to limit or to prevent or interrupt the reactions , including chain reactions, degradation.
  • US Patent 5686016 cites additives used to limit the degradation of absorbent solutions used for the deacidification of natural gas, in particular oximes.
  • US Patent 7056482 cites additives used to limit the degradation of absorbent solutions used for C0 2 capture, in particular thiosulphates and sulphites.
  • the present invention provides a family of degradation inhibiting additives which makes it possible in particular to reduce the degradation of an absorbent solution implemented for the absorption of acidic compounds contained in a gaseous effluent, the absorbent solution comprising amine compounds in aqueous solution. .
  • the invention describes an absorbent solution for absorbing the acidic compounds of a gaseous effluent, said solution comprising: a) at least one amine,
  • R is selected from:
  • X is selected from:
  • a hydrocarbon group comprising between 1 and 20 carbon atoms
  • At least one of the radicals R 2, R 3, R 4 and X may be a hydrocarbon group comprising, in addition, at least one heteroatom.
  • the radicals R3 and R4 can be linked together by a covalent bond to form a heterocycle having between 5 and 8 atoms.
  • R2 may be a hydrocarbon group further comprising at least one halogen.
  • the absorbent solution may comprise between 10% and 99% by weight of amine, between 1% and 90% by weight of water and between 5 ppm and 5% by weight of degradation inhibiting compound.
  • the degradation inhibiting compound may be selected from the group containing 5-methyl-1S, -thiadiazole-thiol, 5-amino-1,3,4-thiadiazole-2-thiol, 5-methylamino-1 3,4-thiadiazole-2-thiol, 2-amino-5- (methylthio) -1,3,4-thiadiazole, 2-amino-5- (ethylthio) -1,3,4-thiadiazole, a salt of 5-methyl-1,3,4-thiadiazole-2-thiol, a salt of 5-amino-1,3,4-thiadiazole-2-thiol, a salt of 5-methylamino-1,3,4- thiadiazole-2-thiol, a salt of 2-amino-5- (methylthio) -1,3,4-thiadiazole and a salt of 2-amino-5- (ethylthio) -1,3,4-thiadiazole.
  • the amine may be chosen from the group containing: ⁇ , ⁇ , ⁇ ', ⁇ ', ⁇ '' - pentamethyldiethylenetriamine, piperazine, monoethanolamine, diethanolamine, methyldiethanolamine, diisopropanolamine, diglycolamine, a salt of glycine and a salt of taurine.
  • the degradation inhibiting compound may be 5-methyl-1,3,4-thiadiazole-2-thiol.
  • the absorbent solution may comprise at least 39% by weight of monoethanolamine.
  • the invention also describes a process for absorbing acidic compounds contained in a gaseous effluent, in which the gaseous effluent is brought into contact with an aqueous solution containing at least one amine, and in which the degradation of said amine is controlled by introducing in said aqueous solution at least one degradation inhibiting compound having the following general formula:
  • R is selected from:
  • X is selected from:
  • a hydrocarbon group comprising between 1 and 20 carbon atoms
  • the aqueous solution can be used to absorb acidic compounds contained in one of the effluents of the group containing the natural gas, the combustion fumes, the synthesis gases, the refinery gases, the gases obtained. at the bottom of the Claus process, biomass fermentation gases, cement gases and incinerator fumes.
  • the gaseous effluent may comprise at least 500 ppm by volume of oxygen.
  • At least one degradation inhibiting compound selected from the group containing: 5-methyl-1,3,4-thiadiazole-2-thiol, 5-amino-1,3,4-thiadiazole may be introduced into the aqueous solution.
  • the degradation of the monoethanolamine in aqueous solution implemented to capture the CO2 contained in combustion fumes can be limited by adding to the aqueous solution at least one degradation inhibiting compound according to the following: 5-methyl-1, 3,4 thiadiazole-2-thiol.
  • FIG. 1 representing the NH 3 content in the gas treated with an absorbent solution as a function of the addition or not of additives inhibiting degradation in the absorbent solution.
  • the inventors have shown that the degradation of an absorbent solution comprising organic compounds provided with an amine function in aqueous solution is substantially reduced in the presence of a small amount of degradation inhibiting additives described hereinafter.
  • the degradation inhibiting additives according to the invention are compounds belonging to the family of thiadiazole derivatives defined by the general formula:
  • R is selected from:
  • said radical -R1-R2 may contain hydroxyl, ketone, carboxylic, amine or nitrile functions.
  • R3 and R4 are independent and therefore are not interconnected.
  • R3 and R4 can be linked together to form a heterocycle for example with 5, 6, 7 or 8 atoms.
  • An alkaline element preferably sodium, potassium or lithium,
  • the molecules of the invention may also exist in their so-called tautomeric form when this is allowed, and this, in compliance with the rules of organic chemistry.
  • the absorbent solutions according to the invention can be used to deacidify the following gaseous effluents: natural gas, synthesis gases, combustion fumes, refinery gases, gases obtained at the bottom of the Claus process, the gases of fermentation of biomass, cement gas, incinerator fumes.
  • gaseous effluents contain one or more of the following acidic compounds: CO2, H 2 S, mercaptans, COS, SO 2, NO 2, CS 2 .
  • the process according to the invention can be used to absorb acidic compounds contained in a gaseous effluent containing oxygen, such as combustion fumes.
  • the oxygen content in the gaseous effluent may be greater than 500 ppm by volume, preferably greater than 0.5%, or even at least 1%, 3% or 5% by volume. In general, the oxygen content in the gaseous effluent remains below 20% by volume.
  • the combustion fumes are produced in particular by the combustion of hydrocarbons, biogas, coal in a boiler or for a combustion gas turbine, for example for the purpose of producing electricity. These fumes can comprise between 50% and 90% of nitrogen, between 5% and 20% of carbon dioxide.
  • the fumes generally comprise at least 500 ppm by volume, preferably at least 1% by volume, or even at least 2%, 3% or 5% by volume of oxygen, up to a content which generally does not exceed 20% by volume. 'oxygen.
  • the implementation of an absorbent solution for deacidifying a gaseous effluent is generally carried out by performing an absorption step followed by a regeneration step.
  • the absorption step consists of contacting the gaseous effluent with the absorbing solution.
  • the organic compounds having an amine function of the absorbent solution react with the acidic compounds contained in the effluent so as to obtain a gaseous effluent depleted of acidic compounds and an absorbent solution enriched in acidic compounds.
  • the regeneration step includes heating and, optionally, relaxing, at least a portion of the absorbent solution enriched in acidic compounds to release the acidic compounds in gaseous form.
  • the regenerated absorbent solution that is to say depleted in acidic compounds is recycled to the absorption step.
  • the absorbent solution according to the invention comprises organic compounds in aqueous solution.
  • the organic compounds are amines, that is to say that they comprise at least one amine function.
  • the organic compounds may be in variable concentration, for example between 10% and 99% by weight, preferably between 20% and 75% by weight, and even between 20% and 50% by weight, in the aqueous solution.
  • the absorbent solution may contain between 1% and 90% by weight of water, preferably between 25% and 80% by weight, and even between 50% and 70% by weight of water.
  • the organic compounds are amines such as ⁇ , ⁇ , ⁇ ', ⁇ ', ⁇ '' - pentamethyldiethylenetriamine or piperazine.
  • piperazine is used for the treatment of natural gas and for the decarbonation of combustion fumes.
  • the organic compounds may also be alkanolamines such as monoethanolamine (MEA), diethanolamine (DEA), methyldiethanolamine (MDEA), diisopropanolamine (DIPA) or diglycolamine.
  • alkanolamines such as monoethanolamine (MEA), diethanolamine (DEA), methyldiethanolamine (MDEA), diisopropanolamine (DIPA) or diglycolamine.
  • MDEA and DEA are commonly used for deacidification of natural gas.
  • MEA is more particularly used for the decarbonation of combustion fumes.
  • the organic compounds may also be amino acid salts such as the glycine or taurine salts which are notably used for the capture of CO2 in the combustion fumes.
  • the absorbent solution according to the invention may contain compounds which physically absorb at least partially one or more acidic compounds of the gaseous effluent.
  • the absorbent solution may comprise between 5% and 50% by weight of absorbent compounds of a physical nature such as, for example, methanol, sulfolane or N-formyl morpholine.
  • Another advantage of the invention lies in the fact that the use of degradation inhibitor additives according to the invention makes it possible to increase the concentration of amines commonly used by those skilled in the art and thus to increase the performance of the process : Increasing the capacity and speed of absorption of the acidic compounds by the absorbing solution resulting in a reduction of investment costs and operating costs of the industrial unit. Indeed, as shown below in Example 1, in the absence of degradation inhibiting additives, the degradation rate of the amines increases with the increase in the concentration of amines. Thus, for example in the case of the use of an aqueous solution of MEA (monoethanolamine) for the capture of CO 2 in combustion fumes, the concentration of MEA is commonly limited to 30% by weight to limit the degradation of this amine. .
  • MEA monoethanolamine
  • concentration of amine is defined as weight percentage in water before C0 2 absorption.
  • an absorbent solution used for the capture of C0 2 in a combustion smoke and containing a degradation inhibitor additive according to the invention may contain more than 30% by weight. and preferably more than 35% by weight of MEA, a good value of the concentration of MEA being at least equal to 39% by weight.
  • the following degradation inhibitor compounds are preferably used:
  • the salts of the degradation-inhibiting compounds according to the invention can be obtained for example by their neutralization with the aid of a hydroxide or an alkaline carbonate (preferably a sodium or potassium hydroxide or carbonate), alkaline earth metal or ammonium or with an amine present in the absorbent solution.
  • a hydroxide or an alkaline carbonate preferably a sodium or potassium hydroxide or carbonate
  • alkaline earth metal or ammonium with an amine present in the absorbent solution.
  • the functions having an acidic character such as for example the thiol functions and for example the possible carboxylic acid functions, may be partially or completely neutralized.
  • the salts of the degradation inhibitor compounds according to the invention can also be obtained for example by their neutralization using an organic or inorganic acid. In this case, it is at least one nitrogen atom present on the molecule that is protonated.
  • the degradation inhibitor compounds listed in the preceding paragraph are particularly well suited to the prevention of degradation of amines in aqueous solution implemented in a CO 2 capture process contained in combustion fumes.
  • 5-methyl-1,3,4-thiadiazole-2-thiol is used to limit the degradation of an amine, in particular MEA, in aqueous solution used to deacidify an effluent. gaseous, especially in the context of capturing C0 2 contained in combustion fumes.
  • the absorbent solution according to the invention comprises an amount of degradation inhibiting additives defined by the general formula described above.
  • the absorbent solution may comprise one or more different degradation inhibiting additives corresponding to said general formula.
  • the degradation inhibitor additives according to the invention may be combined with other degradation inhibitor compounds of different chemical families.
  • the absorbent solution comprises between 5 ppm and 5% by weight of degradation inhibiting additives according to the invention, preferably from 50 ppm to 2% by weight, and an excellent content of degradation inhibiting additives in the solution being between 100 ppm and 1% by weight.
  • the amines of the absorbent solution can be degraded in a use according to the invention generating a consumption of the amine.
  • This example shows that the use of amine degradation inhibiting additives greatly limits the degradation of said amines.
  • This example further shows that in the case of MEA (monoethanolamine) the use of degradation inhibitor additives according to the invention allows the increase of amine concentration by 30% by weight, a concentration commonly used by those skilled in the art. at 40% weight without increasing degradation.
  • MEA solution monoethanolamine
  • deionized water 100 g of MEA solution (monoethanolamine) 30% or 40% by weight in deionized water are placed in a glass reactor surmounted by a condenser to prevent evaporation of the water.
  • the reactor is heated to 80 ° C in an electric heating block.
  • the solution is stirred at 1000 rpm by a magnetic bar.
  • the presence of counter blades prevents the formation of a vortex.
  • a gas is brought into contact with the solution by means of a dip tube for 7 days at atmospheric pressure. According to the tests, the nature of the gas brought into contact with the solution is varied. Similarly, the tests are carried out either in the absence or in the presence of various additives degradation inhibitors incorporated in the aqueous solution of amine at 0.25% by weight.
  • the gas brought into contact with the solution is a mixture of 7NI / h of nitrogen and 0.033 Nl / h of CO 2 produced in a mixing chamber.
  • the gas comprises only CO 2 and nitrogen.
  • the gas brought into contact with the solution is a mixture of 7NI / h of atmospheric air, that is to say unpurified ambient air and 0.033 Nl / h C0 2 produced in a mixing chamber.
  • the gas contains CO 2 , nitrogen and oxygen, the oxygen content in the gas being about 21%.
  • a gas chromatographic analysis of the solution thus degraded is carried out at the end of the test.
  • the chromatographic method uses a polar column, a carrier gas, helium, an internal standard, triethylene glycol and FID (Flame Induced Detection) detection. This analysis makes it possible to determine the residual concentration of MEA.
  • Table 1 shows the average degradation rates of MEA in the following cases:
  • Table 1 Comparison of average degradation rates of MEA 30% and 40% by weight in the absence of a degradation inhibitor additive according to the invention.
  • Table 1 confirms that an aqueous solution of 40 wt% MEA degrades faster than a 30 wt% MEA solution. So for one duration, the degraded MEA mass is greater in the case of an aqueous solution of MEA 40% by weight.
  • Table 2 gives the degradation rates of an aqueous solution of MEA (monoethanolamine) 40% by weight, in the presence of a degradation inhibitor additive or not and subjected to a gas containing nitrogen, CO 2 and containing or no oxygen:
  • Table 2 Comparison of degradation rates of the MEA 40% weight obtained in water at 80 ° C in the different cases.
  • the degradation of the MEA is brought to the same level as that observed in the absence of oxygen, that is to say considered as zero because lower than the uncertainty of the measure which is 3%.
  • the additives according to the invention effectively combat the effect of oxygen on the degradation of MEA. It is clear that in the presence of an additive according to the invention, the degradation of MEA at 40% by weight in water can be considered as zero because lower than the uncertainty of the measure which is 3%.
  • the additives according to the invention make it possible to increase the concentration of amine commonly used by those skilled in the art without increasing the degradation of the amine.
  • the amines can be degraded by the oxygen generating the formation of volatile products, which are entrained in the gaseous effluents of the process.
  • volatile products which are entrained in the gaseous effluents of the process.
  • large amounts of ammonia are formed.
  • the ammonia thus formed is entrained in the atmosphere with the treated fumes, which poses problems as regards the protection of the environment.
  • This example shows that the use of amine degradation inhibiting additives greatly limits the formation of volatile products.
  • This example further shows that in the case of MEA (monoethanolamine) the use of degradation inhibitor additives according to the invention allows the increase of amine concentration by 30% by weight, a concentration commonly used by those skilled in the art. at 40% weight without increasing the formation of volatile products.
  • MEA monoethanolamine
  • This example gives the results obtained with an aqueous solution of MEA at 40% by weight.
  • FIG. 1 shows a follow-up of the concentration of ammonia in the gas leaving the reactor in cases 2 and 4 defined in example 1.
  • [A] corresponds to the concentration of ammonia in ppm volume in the exit gas of the reactor, t represents the time expressed in days.
  • Cases 2 and 4 are respectively represented by curve 2 with black circles and curve 4 with white rhombuses.
  • the ammonia concentration in the gas leaving the reactor is determined by an online Fourier Transform Infra-Red spectrometry analysis.
  • the NH 3 content is less than 10 ppm for the duration of the test whereas it rapidly exceeds 2000 ppm without additive degradation inhibitor. It is clear that in the presence of an additive according to the invention, the ammonia emissions related to the degradation of MEA at 40% by weight in water are considerably reduced. This example thus clearly shows, in the case of MEA, that the additives according to the invention make it possible to increase the concentration of amine commonly used by those skilled in the art without increasing the ammonia emissions.
  • the emissions of volatile compounds at the absorber head will be much lower than in the absence of degradation inhibitor additives even if the concentration of amine is increased relative to the concentration commonly used by those skilled in the art.

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  • Engineering & Computer Science (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Chemical Kinetics & Catalysis (AREA)
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Abstract

The degradation of an absorbent solution comprising organic compounds having an amine function in aqueous solution is substantially reduced in the presence of a small amount of degradation inhibitor additives belonging to the family of thiadiazole derivatives defined by the general formula: formula (I). The absorbent solution is used for deacidifying a gaseous effluent.

Description

SOLUTION ABSORBANTE CONTENANT UN INHIBITEUR DE DEGRADATION DERIVE SOUFRE DU THIADIAZOLE ET SON UTILISATION DANS UN PROCEDE D'ABSORPTION  ABSORBENT SOLUTION CONTAINING THIADIAZOLE SULFUR-DERIVED DEGRADATION INHIBITOR AND USE THEREOF IN ABSORPTION PROCESS
La présente invention concerne le domaine de la désacidification d'un effluent gazeux. Plus précisément la présente invention propose des composés pour réduire la dégradation d'une solution absorbante mise en œuvre pour absorber les composés acides contenus dans un effluent gazeux, la solution absorbante comportant des aminés en solution aqueuse. En particulier, l'invention concerne des composés utilisés pour réduire la dégradation des aminés utilisées pour la désacidification de gaz contenant de l'oxygène, comme par exemple les fumées de combustion. The present invention relates to the field of the deacidification of a gaseous effluent. More specifically, the present invention provides compounds for reducing the degradation of an absorbent solution implemented to absorb the acidic compounds contained in a gaseous effluent, the absorbent solution comprising amines in aqueous solution. In particular, the invention relates to compounds used to reduce the degradation of amines used for the deacidification of oxygen-containing gases, such as for example combustion fumes.
La désacidification des effluents gazeux, tels que par exemple le gaz naturel et les fumées de combustion, est généralement réalisée par lavage par une solution absorbante. La solution absorbante permet d'absorber les composés acides présents dans l'effluent gazeux (H2S, mercaptans, C02, COS, S02, CS2). The deacidification of gaseous effluents, such as, for example, natural gas and combustion fumes, is generally carried out by washing with an absorbent solution. The absorbent solution makes it possible to absorb the acid compounds present in the gaseous effluent (H 2 S, mercaptans, CO 2 , COS, SO 2 , CS 2 ).
La désacidification de ces effluents, notamment la décarbo natation et la désulfuration, impose des contraintes spécifiques à la solution absorbante, en particulier une stabilité thermique et chimique notamment face aux impuretés de l'effluent, à savoir essentiellement l'oxygène, les SOx et les NOx. L'oxygène peut aussi entrer en contact avec la solution absorbante sans être forcément présent dans l'effluent gazeux à traiter comme dans le cas par exemple d'une entrée accidentelle d'air au niveau des bacs de stockage de solution absorbante.  The deacidification of these effluents, in particular decarbonation and desulfurization, imposes specific constraints on the absorbent solution, in particular a thermal and chemical stability, especially with regard to the impurities of the effluent, namely essentially oxygen, SOx and NOx. The oxygen may also come into contact with the absorbent solution without necessarily being present in the gaseous effluent to be treated, as in the case, for example, of an accidental entry of air into the absorbent solution storage tanks.
Les solutions absorbantes les plus utilisées aujourd'hui sont les solutions aqueuses d'alcanolamines. On peut citer le document FR 2 820 430 qui propose des procédés de désacidification d'effluents gazeux.  Absorbent solutions most used today are aqueous solutions of alkanolamines. We can cite the document FR 2 820 430 which proposes processes for deacidification of gaseous effluents.
Toutefois, il est bien connu de l'homme de l'art que ces aminés présentent l'inconvénient de se dégrader dans les conditions de mise en œuvre.  However, it is well known to those skilled in the art that these amines have the disadvantage of degrading under the conditions of implementation.
En particulier, les aminés peuvent être dégradées par l'oxygène engendrant une consommation de l'aminé et la formation de produits de dégradation qui s'accumulent dans l'unité ou, pour les plus volatils, qui sont entraînés dans les effluents gazeux du procédé. Ainsi, en particulier dans le cas du traitement de fumées en post-combustion dans un procédé utilisant une solution aqueuse de monoéthanolamine (MEA) des quantités importantes d'ammoniac sont formées. L'ammoniac ainsi formé est entraîné dans l'atmosphère avec les fumées traitées ce qui pose des problèmes quant à la protection de l'environnement. In particular, the amines can be degraded by the oxygen generating a consumption of the amine and the formation of degradation products which accumulate in the unit or, for the most volatile, which are entrained in the gaseous effluents of the process. Thus, particularly in the case of post-combustion flue gas treatment in a process using an aqueous monoethanolamine (MEA) solution, large amounts of ammonia are formed. The ammonia thus formed is entrained in the atmosphere with the treated fumes, which poses problems with regard to the protection of the environment.
Dans le cas du captage du C02 dans les fumées issues d'unités industrielles ou de production d'électricité ou d'énergie en général, les phénomènes de dégradation de la solution absorbante aux aminés sont accrus par la présence d'une quantité massive d'oxygène dans la charge à traiter pouvant aller jusqu'à 5% en volume en général. Dans le cas de fumées issues de cycle combiné au gaz naturel, la teneur volumique d'oxygène dans les fumées peut atteindre 15%. In the case of the capture of C0 2 in fumes from industrial units or electricity or energy production in general, the degradation phenomena of the absorbent solution amines are increased by the presence of a massive amount of oxygen in the feed to be treated up to 5% by volume in general. In the case of fumes from the combined cycle with natural gas, the volume content of oxygen in the fumes can reach 15%.
La solution dégradée se caractérise par :  The degraded solution is characterized by:
une baisse de l'absorption des composés acides de la charge par rapport à une solution fraîche d'amine,  a decrease in the absorption of the acidic compounds of the feed compared to a fresh solution of amine,
une augmentation de la densité de la solution absorbante, ainsi que de sa viscosité, pouvant entraîner une perte de performance,  an increase in the density of the absorbing solution, as well as its viscosity, which can lead to a loss of performance,
- la formation d'amines plus volatiles polluant le gaz traité et le gaz acide issu de l'étape de régénération : ammoniac, méthylamine, diméthylamine et triméthylamine par exemple selon la nature de l'aminé utilisée, une accumulation de produits de dégradation dans la solution absorbante qui peut entraîner la nécessité d'un traitement de la solution dégradée, - d'éventuels problèmes de moussage dus aux produits de dégradation. the formation of more volatile amines polluting the treated gas and the acid gas resulting from the regeneration step: ammonia, methylamine, dimethylamine and trimethylamine, for example according to the nature of the amine used, an accumulation of degradation products in the absorbent solution which may cause the need for treatment of the degraded solution, - possible foaming problems due to degradation products.
La dégradation de la solution absorbante pénalise donc les performances et le bon fonctionnement des unités de désacidification des gaz. The degradation of the absorbing solution therefore penalizes the performance and the proper functioning of the gas deacidification units.
Pour pallier le problème de dégradation, à défaut de pouvoir limiter ou supprimer la présence d'oxygène dans la solution absorbante, on ajoute, dans la solution absorbante, des composés dont le rôle est de prévenir ou limiter les phénomènes de dégradation des composés aminés, notamment la dégradation engendrée par les phénomènes d'oxydation. Ces composés sont couramment nommés additifs inhibiteurs de dégradation. Les principaux modes d'action connus des additifs inhibiteurs de dégradation consistent selon leur nature en une réaction de type réduction et/ou en un captage, un piégeage et/ou une stabilisation des radicaux formés dans la solution absorbante afin de limiter ou d'empêcher ou d'interrompre les réactions, notamment les réactions en chaîne, de dégradation. To overcome the problem of degradation, failing to limit or eliminate the presence of oxygen in the absorbent solution is added in the absorbent solution, compounds whose role is to prevent or limit the degradation of amino compounds, in particular the degradation caused by the oxidation phenomena. These compounds are commonly referred to as degradation inhibiting additives. Main modes of action known degradation inhibiting additives consist according to their nature in a reduction-type reaction and / or in a capture, trapping and / or stabilization of the radicals formed in the absorbent solution in order to limit or to prevent or interrupt the reactions , including chain reactions, degradation.
Le brevet US 5686016 cite des additifs utilisés pour limiter la dégradation de solutions absorbantes utilisées pour la désacidification du gaz naturel, en particulier les oximes. US Patent 5686016 cites additives used to limit the degradation of absorbent solutions used for the deacidification of natural gas, in particular oximes.
Le brevet US 7056482 cite des additifs utilisés pour limiter la dégradation de solutions absorbantes utilisées pour le captage du C02, en particulier les thiosulfates et les sulfites. US Patent 7056482 cites additives used to limit the degradation of absorbent solutions used for C0 2 capture, in particular thiosulphates and sulphites.
La présente invention propose une famille d'additifs inhibiteurs de dégradation qui permet notamment de réduire la dégradation d'une solution absorbante mise en œuvre pour l'absorption de composés acides contenus dans un effluent gazeux, la solution absorbante comportant des composés aminés en solution aqueuse. The present invention provides a family of degradation inhibiting additives which makes it possible in particular to reduce the degradation of an absorbent solution implemented for the absorption of acidic compounds contained in a gaseous effluent, the absorbent solution comprising amine compounds in aqueous solution. .
De manière générale, l'invention décrit une solution absorbante pour absorber les composés acides d'un effluent gazeux, ladite solution comportant : a) au moins une aminé, In general, the invention describes an absorbent solution for absorbing the acidic compounds of a gaseous effluent, said solution comprising: a) at least one amine,
b) de l'eau,  (b) water,
c) au moins un composé inhibiteur de dégradation pour limiter la dégradation de ladite aminé, le composé inhibiteur répondant à la formule :
Figure imgf000005_0001
c) at least one degradation inhibiting compound for limiting the degradation of said amine, the inhibiting compound having the formula:
Figure imgf000005_0001
dans laquelle R est choisi parmi :  wherein R is selected from:
• un atome d'hydrogène,  • a hydrogen atom,
• un radical -R1-R2 dans lequel Ri est choisi parmi un atome d'oxygène et un groupement hydrocarboné comprenant 1 à 12 atomes de carbone et dans lequel R2 est un groupement hydrocarboné comprenant 1 à 12 atomes de carbone, • un groupement -NR3R4 dans lequel R3 et R4 sont indépendamment choisis parmi un atome d'hydrogène et un groupement hydrocarboné comportant entre 1 et 20 atomes de carbone, A radical -R 1 -R 2 in which R 1 is chosen from an oxygen atom and a hydrocarbon group comprising 1 to 12 carbon atoms and in which R 2 is a hydrocarbon group comprising 1 to 12 carbon atoms, A group -NR3R4 in which R3 and R4 are independently chosen from a hydrogen atom and a hydrocarbon group containing between 1 and 20 carbon atoms,
dans laquelle X est choisi parmi :  wherein X is selected from:
• un atome d'hydrogène,  • a hydrogen atom,
• un groupement hydrocarboné comportant entre 1 et 20 atomes de carbone,  A hydrocarbon group comprising between 1 and 20 carbon atoms,
• un élément alcalin,  • an alkaline element,
· un élément alcalino-terreux,  An alkaline earth element,
• un métal monovalent ou multivalent  • a monovalent or multivalent metal
• un cation ammonium NH + ou résultant de la protonation d'une fonction aminé An ammonium NH + cation or resulting from the protonation of an amine function
• un cation phosphonium.  A phosphonium cation.
Selon l'invention, au moins un des radicaux R2, R3, R4 et X peut être un groupement hydrocarboné comportant, en outre, au moins un hétéroatome. According to the invention, at least one of the radicals R 2, R 3, R 4 and X may be a hydrocarbon group comprising, in addition, at least one heteroatom.
Les radicaux R3 et R4 peuvent être reliés entre eux par une liaison covalente pour former un hétérocycle comportant entre 5 et 8 atomes.  The radicals R3 and R4 can be linked together by a covalent bond to form a heterocycle having between 5 and 8 atoms.
R2 peut être un groupement hydrocarboné comportant, en outre, au moins un halogène.  R2 may be a hydrocarbon group further comprising at least one halogen.
La solution absorbante peut comporter entre 10% et 99% poids d'amine, entre 1 % et 90% poids d'eau et entre 5 ppm et 5% poids de composé inhibiteur de dégradation.  The absorbent solution may comprise between 10% and 99% by weight of amine, between 1% and 90% by weight of water and between 5 ppm and 5% by weight of degradation inhibiting compound.
Le composé inhibiteur de dégradation peut être choisi parmi le groupe contenant le 5-méthyl-1.S^-thiadiazole^-thiol, le 5-amino-1 ,3,4-thiadiazole-2- thiol, le 5-méthylamino-1 ,3,4-thiadiazole-2-thiol, le 2-amino-5-(méthylthio)-1 ,3,4- thiadiazole, le 2-amino-5-(éthylthio)-1 ,3,4-thiadiazole, un sel du 5-méthyl-1 ,3,4- thiadiazole-2-thiol, un sel du 5-amino-1 ,3,4-thiadiazole-2-thiol, un sel du 5- méthylamino-1 ,3,4-thiadiazole-2-thiol, un sel du 2-amino-5-(méthylthio)-1 ,3,4- thiadiazole et un sel du 2-amino-5-(éthylthio)-1 ,3,4-thiadiazole.  The degradation inhibiting compound may be selected from the group containing 5-methyl-1S, -thiadiazole-thiol, 5-amino-1,3,4-thiadiazole-2-thiol, 5-methylamino-1 3,4-thiadiazole-2-thiol, 2-amino-5- (methylthio) -1,3,4-thiadiazole, 2-amino-5- (ethylthio) -1,3,4-thiadiazole, a salt of 5-methyl-1,3,4-thiadiazole-2-thiol, a salt of 5-amino-1,3,4-thiadiazole-2-thiol, a salt of 5-methylamino-1,3,4- thiadiazole-2-thiol, a salt of 2-amino-5- (methylthio) -1,3,4-thiadiazole and a salt of 2-amino-5- (ethylthio) -1,3,4-thiadiazole.
L'amine peut être choisie parmi le groupe contenant : la Ν,Ν,Ν',Ν',Ν''-pentaméthyldiéthylènetriamine, la pipérazine, la monoéthanolamine, la diéthanolamine, la méthyldiéthanolamine, la diisopropanolamine, la diglycolamine, un sel de la glycine et un sel de la taurine. The amine may be chosen from the group containing: Ν, Ν, Ν ', Ν', Ν '' - pentamethyldiethylenetriamine, piperazine, monoethanolamine, diethanolamine, methyldiethanolamine, diisopropanolamine, diglycolamine, a salt of glycine and a salt of taurine.
De préférence, dans le cas où l'aminé est la monoéthanolamine, le composé inhibiteur de dégradation peut être le 5-méthyl-1 ,3,4-thiadiazole-2-thiol.  Preferably, in the case where the amine is monoethanolamine, the degradation inhibiting compound may be 5-methyl-1,3,4-thiadiazole-2-thiol.
La solution absorbante peut comporter au moins 39% poids de monoéthanolamine.  The absorbent solution may comprise at least 39% by weight of monoethanolamine.
L'invention décrit également un procédé pour absorber des composés acides contenus dans un effluent gazeux, dans lequel on met en contact l'effluent gazeux avec une solution aqueuse comportant au moins une amine, et dans lequel on contrôle la dégradation de ladite amine en introduisant dans ladite solution aqueuse au moins un composé inhibiteur de dégradation répondant à la formule générale suivante :
Figure imgf000007_0001
The invention also describes a process for absorbing acidic compounds contained in a gaseous effluent, in which the gaseous effluent is brought into contact with an aqueous solution containing at least one amine, and in which the degradation of said amine is controlled by introducing in said aqueous solution at least one degradation inhibiting compound having the following general formula:
Figure imgf000007_0001
dans laquelle R est choisi parmi :  wherein R is selected from:
• un atome d'hydrogène,  • a hydrogen atom,
• un radical -R1-R2 dans lequel Ri est choisi parmi un atome d'oxygène et un groupement hydrocarboné comprenant 1 à 12 atomes de carbone et dans lequel R2 est un groupement hydrocarboné comprenant 1 à 12 atomes de carbone, A radical -R 1 -R 2 in which R 1 is chosen from an oxygen atom and a hydrocarbon group comprising 1 to 12 carbon atoms and in which R 2 is a hydrocarbon group comprising 1 to 12 carbon atoms,
• un groupement -NR3R4 dans lequel R3 et R4 sont indépendamment choisis parmi un atome d'hydrogène et un groupement hydrocarboné comportant entre 1 et 20 atomes de carbone, A group -NR3R4 in which R3 and R4 are independently chosen from a hydrogen atom and a hydrocarbon group containing between 1 and 20 carbon atoms,
dans laquelle X est choisi parmi :  wherein X is selected from:
• un atome d'hydrogène,  • a hydrogen atom,
• un groupement hydrocarboné comportant entre 1 et 20 atomes de carbone,  A hydrocarbon group comprising between 1 and 20 carbon atoms,
• un élément alcalin,  • an alkaline element,
• un élément alcalino-terreux,  • an alkaline earth element,
• un métal monovalent ou multivalent • un cation ammonium NH4 + ou résultant de la protonation d'une fonction aminé • a monovalent or multivalent metal An ammonium NH 4 + cation or resulting from the protonation of an amine function
• un cation phosphonium. Selon l'invention, la solution aqueuse peut être mise en œuvre pour absorber des composés acides contenus dans l'un des effluents du groupe contenant le gaz naturel, les fumées de combustion, les gaz de synthèse, les gaz de raffinerie, les gaz obtenus en queue du procédé Claus, les gaz de fermentation de biomasse, les gaz de cimenterie et les fumées d'incinérateur.  A phosphonium cation. According to the invention, the aqueous solution can be used to absorb acidic compounds contained in one of the effluents of the group containing the natural gas, the combustion fumes, the synthesis gases, the refinery gases, the gases obtained. at the bottom of the Claus process, biomass fermentation gases, cement gases and incinerator fumes.
L'effluent gazeux peut comporter au moins 500ppm volumique d'oxygène. The gaseous effluent may comprise at least 500 ppm by volume of oxygen.
On peut introduire dans la solution aqueuse au moins un composé inhibiteur de dégradation choisi parmi le groupe contenant : le 5-méthyl-1 ,3,4- thiadiazole-2-thiol, le 5-amino-1 ,3,4-thiadiazole-2-thiol, le 5-méthylamino-1 ,3,4- thiadiazole-2-thiol, le 2-amino-5-(méthylthio)-1 ,3,4-thiadiazole, le 2-amino-5- (éthylthio)-1 ,3,4-thiadiazole, un sel du 5-méthyl-1 ,3,4-thiadiazole-2-thiol, un sel du 5-amino-1 ,3,4-thiadiazole-2-thiol, un sel du 5-méthylamino-1 ,3,4-thiadiazole-2- thiol, un sel du 2-amino-5-(méthylthio)-1 ,3,4-thiadiazole et un sel du 2-amino-5- (éthylthio)-l ,3,4-thiadiazole. At least one degradation inhibiting compound selected from the group containing: 5-methyl-1,3,4-thiadiazole-2-thiol, 5-amino-1,3,4-thiadiazole, may be introduced into the aqueous solution. 2-thiol, 5-methylamino-1,3,4-thiadiazole-2-thiol, 2-amino-5- (methylthio) -1,3,4-thiadiazole, 2-amino-5- (ethylthio) 1, 3,4-thiadiazole, a salt of 5-methyl-1,3,4-thiadiazole-2-thiol, a salt of 5-amino-1,3,4-thiadiazole-2-thiol, a salt of 5-methylamino-1,3,4-thiadiazole-2-thiol, a salt of 2-amino-5- (methylthio) -1,3,4-thiadiazole and a salt of 2-amino-5- (ethylthio) - 1,4-thiadiazole.
On peut limiter la dégradation de la monoéthanolamine en solution aqueuse mise en œuvre pour capter le CO2 contenu dans des fumées de combustion, en ajoutant dans la solution aqueuse au moins un composé inhibiteur de dégradation suivant : le 5-méthyl-1 ,3,4-thiadiazole-2-thiol.  The degradation of the monoethanolamine in aqueous solution implemented to capture the CO2 contained in combustion fumes can be limited by adding to the aqueous solution at least one degradation inhibiting compound according to the following: 5-methyl-1, 3,4 thiadiazole-2-thiol.
D'autres caractéristiques et avantages de l'invention seront mieux compris et apparaîtront clairement à la lecture de la description faite ci-après, en référence à la figure 1 représentant la teneur en NH3 dans le gaz traité par une solution absorbante en fonction de l'ajout ou non d'additifs inhibiteurs de dégradation dans la solution absorbante. Afin de réduire la dégradation d'une solution absorbante, les inventeurs ont montré que la dégradation d'une solution absorbante comportant des composés organiques munis d'une fonction aminé en solution aqueuse est sensiblement réduite en présence d'une faible quantité d'additifs inhibiteurs de dégradation décrits ci-après. Other features and advantages of the invention will be better understood and will be clear from reading the description given below, with reference to FIG. 1 representing the NH 3 content in the gas treated with an absorbent solution as a function of the addition or not of additives inhibiting degradation in the absorbent solution. In order to reduce the degradation of an absorbent solution, the inventors have shown that the degradation of an absorbent solution comprising organic compounds provided with an amine function in aqueous solution is substantially reduced in the presence of a small amount of degradation inhibiting additives described hereinafter.
Les additifs inhibiteurs de dégradation selon l'invention sont des composés appartenant à la famille des dérivés du thiadiazole définis par la formule générale :
Figure imgf000009_0001
The degradation inhibiting additives according to the invention are compounds belonging to the family of thiadiazole derivatives defined by the general formula:
Figure imgf000009_0001
dans laquelle R est choisi parmi : wherein R is selected from:
• un atome d'hydrogène,  • a hydrogen atom,
• un radical -R1-R2 avec Ri étant un groupement hydrocarboné comprenant 1 à 12 atomes de carbone ou un atome d'oxygène et R2 étant un groupement hydrocarboné comprenant 1 à 12 atomes de carbone, saturé ou non, linéaire, branché ou cyclique, hétérocyclique ou aromatique pouvant éventuellement renfermer un ou plusieurs hétéroatomes, par exemple choisis parmi l'azote, l'oxygène et le soufre, et/ou pouvant renfermer un ou plusieurs halogènes. Par exemple, ledit radical -R1-R2 peut renfermer des fonctions hydroxyles, cétones, carboxyliques, aminés ou nitriles. A radical -R 1 -R 2 with R 1 being a hydrocarbon group comprising 1 to 12 carbon atoms or an oxygen atom and R 2 being a hydrocarbon group comprising 1 to 12 carbon atoms, saturated or unsaturated, linear, branched or cyclic, heterocyclic or aromatic compound which may optionally contain one or more heteroatoms, for example selected from nitrogen, oxygen and sulfur, and / or may contain one or more halogens. For example, said radical -R1-R2 may contain hydroxyl, ketone, carboxylic, amine or nitrile functions.
• un groupement' -NR3R4 avec R3 et R4 choisis parmi un atome d'hydrogène, un groupement hydrocarboné renfermant 1 à 20 atomes de carbone et de préférence de 1 à 6 atomes de carbone, le groupement hydrocarboné pouvant renfermer un ou plusieurs hétéroatomes, par exemple choisis parmi l'azote, l'oxygène et le soufre. Selon un mode de réalisation, R3 et R4 sont indépendants et donc ne sont pas reliés entre eux. Alternativement, R3 et R4 peuvent être reliés entre eux pour former un hétérocycle par exemple à 5, 6, 7 ou 8 atomes. dans laquelle X est choisi parmi A group -NR3R4 with R3 and R4 chosen from a hydrogen atom, a hydrocarbon group containing 1 to 20 carbon atoms and preferably from 1 to 6 carbon atoms, the hydrocarbon group possibly containing one or more heteroatoms, examples selected from nitrogen, oxygen and sulfur. According to one embodiment, R3 and R4 are independent and therefore are not interconnected. Alternatively, R3 and R4 can be linked together to form a heterocycle for example with 5, 6, 7 or 8 atoms. wherein X is selected from
• un atome d'hydrogène, • un groupement hydrocarboné renfermant 1 à 20 atomes de carbone et de préférence de 1 à 6 atomes de carbone, le groupement hydrocarboné pouvant renfermer un ou plusieurs hétéroatomes, par exemple choisis parmi l'azote, l'oxygène et le soufre, • a hydrogen atom, A hydrocarbon group containing 1 to 20 carbon atoms and preferably 1 to 6 carbon atoms, the hydrocarbon group may contain one or more heteroatoms, for example chosen from nitrogen, oxygen and sulfur,
• un élément alcalin, de préférence le sodium, le potassium ou le lithium,  An alkaline element, preferably sodium, potassium or lithium,
• un élément alcalino-terreux,  • an alkaline earth element,
• un métal monovalent ou multivalent,  • a monovalent or multivalent metal,
• un cation ammonium NH4 + ou résultant de la protonation d'une fonction aminé, An ammonium NH 4 + cation or resulting from the protonation of an amine function,
• un cation phosphonium.  A phosphonium cation.
Lorsque X est un élément multivalent, la formule générale peut s'écrire When X is a multivalent element, the general formula can be written
Figure imgf000010_0001
a
Figure imgf000010_0001
at
avec a et b étant des nombres entiers permettant le respect de la neutralité ou des valences dans le respect des règles de la chimie. with a and b being integers allowing the respect of the neutrality or the valences in the respect of the rules of the chemistry.
Les molécules de l'invention peuvent aussi exister sous leur forme dite tautomère lorsque cela est permis, et ce, dans le respect des règles de la chimie organique. The molecules of the invention may also exist in their so-called tautomeric form when this is allowed, and this, in compliance with the rules of organic chemistry.
Les solutions absorbantes selon l'invention peuvent être mises en œuvre pour désacidifier les effluents gazeux suivants : le gaz naturel, les gaz de synthèse, les fumées de combustion, les gaz de raffinerie, les gaz obtenus en queue du procédé Claus, les gaz de fermentation de biomasse, les gaz de cimenterie, les fumées d'incinérateur. Ces effluents gazeux contiennent un ou plusieurs des composés acides suivants : le CO2, l'H2S, des mercaptans, du COS, du SO2, du NO2, du CS2. En particulier, le procédé selon l'invention, peut être mis en œuvre pour absorber des composés acides contenus dans un effluent gazeux contenant de l'oxygène, comme par exemple les fumées de combustion. La teneur en oxygène dans l'effluent gazeux peut être supérieure à 500ppm en volume, de préférence supérieure à 0,5%, voire au moins 1%, 3% ou 5% volumique. En général, la teneur en oxygène dans l'effluent gazeux reste inférieure à 20% en volume. Les fumées de combustion sont produites notamment par la combustion d'hydrocarbures, de biogaz, de charbon dans une chaudière ou pour une turbine à gaz de combustion, par exemple dans le but de produire de l'électricité. Ces fumées peuvent comporter entre 50 % et 90 % d'azote, entre 5 % et 20 % de dioxyde de carbone. Les fumées comportent en général au moins 500ppm volumique, de préférence au moins 1 % volumique, voire au moins 2%, 3% ou 5% volumique d'oxygène, jusqu'à une teneur qui en général n'excède pas 20 % volume d'oxygène. The absorbent solutions according to the invention can be used to deacidify the following gaseous effluents: natural gas, synthesis gases, combustion fumes, refinery gases, gases obtained at the bottom of the Claus process, the gases of fermentation of biomass, cement gas, incinerator fumes. These gaseous effluents contain one or more of the following acidic compounds: CO2, H 2 S, mercaptans, COS, SO 2, NO 2, CS 2 . In particular, the process according to the invention can be used to absorb acidic compounds contained in a gaseous effluent containing oxygen, such as combustion fumes. The oxygen content in the gaseous effluent may be greater than 500 ppm by volume, preferably greater than 0.5%, or even at least 1%, 3% or 5% by volume. In general, the oxygen content in the gaseous effluent remains below 20% by volume. The combustion fumes are produced in particular by the combustion of hydrocarbons, biogas, coal in a boiler or for a combustion gas turbine, for example for the purpose of producing electricity. These fumes can comprise between 50% and 90% of nitrogen, between 5% and 20% of carbon dioxide. The fumes generally comprise at least 500 ppm by volume, preferably at least 1% by volume, or even at least 2%, 3% or 5% by volume of oxygen, up to a content which generally does not exceed 20% by volume. 'oxygen.
La mise en œuvre d'une solution absorbante pour désacidifier un effluent gazeux est généralement réalisée en effectuant une étape d'absorption suivie d'une étape de régénération. L'étape d'absorption consiste à mettre en contact l'effluent gazeux avec la solution absorbante. Lors du contact, les composés organiques munis d'une fonction aminé de la solution absorbante réagissent avec les composés acides contenus dans l'effluent de manière à obtenir un effluent gazeux appauvri en composés acides et une solution absorbante enrichie en composés acides. L'étape de régénération consiste notamment à chauffer et, éventuellement à détendre, au moins une partie de la solution absorbante enrichie en composés acides afin de libérer les composés acides sous forme gazeuse. La solution absorbante régénérée, c'est-à-dire appauvrie en composés acides est recyclée à l'étape d'absorption.  The implementation of an absorbent solution for deacidifying a gaseous effluent is generally carried out by performing an absorption step followed by a regeneration step. The absorption step consists of contacting the gaseous effluent with the absorbing solution. Upon contact, the organic compounds having an amine function of the absorbent solution react with the acidic compounds contained in the effluent so as to obtain a gaseous effluent depleted of acidic compounds and an absorbent solution enriched in acidic compounds. The regeneration step includes heating and, optionally, relaxing, at least a portion of the absorbent solution enriched in acidic compounds to release the acidic compounds in gaseous form. The regenerated absorbent solution, that is to say depleted in acidic compounds is recycled to the absorption step.
La solution absorbante selon l'invention comporte des composés organiques en solution aqueuse. De manière générale, les composés organiques sont des aminés, c'est-à-dire qu'ils comportent au moins une fonction aminé. Les composés organiques peuvent être en concentration variable par exemple compris entre 10% et 99% poids, de préférence entre 20% et 75% poids, voire entre 20% et 50% poids, dans la solution aqueuse. La solution absorbante peut contenir entre 1 % et 90% poids d'eau, de préférence entre 25% et 80% poids, voire entre 50% et 70% poids d'eau.  The absorbent solution according to the invention comprises organic compounds in aqueous solution. In general, the organic compounds are amines, that is to say that they comprise at least one amine function. The organic compounds may be in variable concentration, for example between 10% and 99% by weight, preferably between 20% and 75% by weight, and even between 20% and 50% by weight, in the aqueous solution. The absorbent solution may contain between 1% and 90% by weight of water, preferably between 25% and 80% by weight, and even between 50% and 70% by weight of water.
Par exemples les composés organiques sont des aminés tels que la Ν,Ν,Ν',Ν',Ν''-pentaméthyldiéthylènetriamine ou la pipérazine. Par exemple la pipérazine est utilisée pour le traitement du gaz naturel et pour la décarbonatation des fumées de combustion. For example, the organic compounds are amines such as Ν, Ν, Ν ', Ν', Ν '' - pentamethyldiethylenetriamine or piperazine. For example, piperazine is used for the treatment of natural gas and for the decarbonation of combustion fumes.
Les composés organiques peuvent également être des alcanolamines telles que la monoéthanolamine (MEA), la diéthanolamine (DEA), la méthyldiéthanolamine (MDEA), la diisopropanolamine (DIPA) ou la diglycolamine. The organic compounds may also be alkanolamines such as monoethanolamine (MEA), diethanolamine (DEA), methyldiethanolamine (MDEA), diisopropanolamine (DIPA) or diglycolamine.
De préférence, la MDEA et la DEA sont couramment utilisées pour la désacidification du gaz naturel. La MEA est plus particulièrement utilisée pour la décarbonatation des fumées de combustion. Preferably, MDEA and DEA are commonly used for deacidification of natural gas. MEA is more particularly used for the decarbonation of combustion fumes.
Les composés organiques peuvent également être des sels d'acides aminés tels que les sels de la glycine ou de la taurine qui sont notamment mis en œuvre pour le captage du CO2 dans les fumées de combustion.  The organic compounds may also be amino acid salts such as the glycine or taurine salts which are notably used for the capture of CO2 in the combustion fumes.
En outre, la solution absorbante selon l'invention peut contenir des composés qui absorbent physiquement au moins partiellement un ou plusieurs composés acides de l'effluent gazeux. Par exemple la solution absorbante peut comporter entre 5% et 50% poids de composés absorbants à caractère physique tel que par exemple du méthanol, du sulfolane ou de la N-formyl morpholine.  In addition, the absorbent solution according to the invention may contain compounds which physically absorb at least partially one or more acidic compounds of the gaseous effluent. For example, the absorbent solution may comprise between 5% and 50% by weight of absorbent compounds of a physical nature such as, for example, methanol, sulfolane or N-formyl morpholine.
Un autre avantage de l'invention réside dans le fait que l'utilisation d'additifs inhibiteurs de dégradation selon l'invention permet d'augmenter la concentration en aminés communément utilisée par l'homme du métier et d'augmenter ainsi les performances du procédé : augmentation de la capacité et de la vitesse d'absorption des composés acides par la solution absorbante entraînant une réduction des coûts d'investissement et des coûts opératoires de l'unité industrielle. En effet, comme montré ci-après dans l'exemple 1 , en absence d'additifs inhibiteurs de dégradation, la vitesse de dégradation des aminés augmente avec l'augmentation de la concentration en aminés. Ainsi dans le cas par exemple de l'utilisation d'une solution aqueuse de MEA (monoéthanolamine) pour le captage du CO2 dans les fumées de combustion, la concentration en MEA est communément limitée à 30% poids pour limiter la dégradation de cette aminé. II est entendu ici que la concentration en aminé est définie en pourcentage poids dans l'eau avant absorption de C02. Ainsi par exemple, une solution absorbante utilisée pour le captage du C02 dans une fumée de combustion et contenant un additif inhibiteur de dégradation selon l'invention peut contenir plus de 30% poids et de préférence plus de 35% poids de MEA, une bonne valeur de la concentration en MEA étant au moins égale à 39% poids. Another advantage of the invention lies in the fact that the use of degradation inhibitor additives according to the invention makes it possible to increase the concentration of amines commonly used by those skilled in the art and thus to increase the performance of the process : Increasing the capacity and speed of absorption of the acidic compounds by the absorbing solution resulting in a reduction of investment costs and operating costs of the industrial unit. Indeed, as shown below in Example 1, in the absence of degradation inhibiting additives, the degradation rate of the amines increases with the increase in the concentration of amines. Thus, for example in the case of the use of an aqueous solution of MEA (monoethanolamine) for the capture of CO 2 in combustion fumes, the concentration of MEA is commonly limited to 30% by weight to limit the degradation of this amine. . It is understood here that the concentration of amine is defined as weight percentage in water before C0 2 absorption. For example, an absorbent solution used for the capture of C0 2 in a combustion smoke and containing a degradation inhibitor additive according to the invention may contain more than 30% by weight. and preferably more than 35% by weight of MEA, a good value of the concentration of MEA being at least equal to 39% by weight.
Parmi l'ensemble des molécules appartenant à la famille des dérivés de la pyridine dont au moins un substituant contient un atome de soufre, on utilise de préférence les composés inhibiteurs de dégradation suivants : Among all the molecules belonging to the family of pyridine derivatives in which at least one substituent contains a sulfur atom, the following degradation inhibitor compounds are preferably used:
le 5-méthyl-1 ,3,4-thiadiazole-2-thiol, le 5-amino-1 ,3,4-thiadiazole-2-thiol, le 5- méthylamino-1 ,3,4-thiadiazole-2-thiol, le 2-amino-5-(méthylthio)-1 ,3,4-thiadiazole, le 2-amino-5-(éthylthio)-1 ,3,4-thiadiazole, ainsi que les sels des éléments précédemment cités. 5-methyl-1,3,4-thiadiazole-2-thiol, 5-amino-1,3,4-thiadiazole-2-thiol, 5-methylamino-1,3,4-thiadiazole-2-thiol 2-Amino-5- (methylthio) -1,3,4-thiadiazole, 2-amino-5- (ethylthio) -1,3,4-thiadiazole and the salts of the above-mentioned elements.
Les sels des composés inhibiteurs de dégradation selon l'invention peuvent être obtenus par exemple par leur neutralisation à l'aide d'un hydroxyde ou un carbonate alcalin (de préférence un hydroxyde ou un carbonate de sodium ou de potassium), alcalinoterreux ou métallique ou d'ammonium ou à l'aide d'une aminé présente dans la solution absorbante. Dans ce cas, les fonctions présentant un caractère acide, telles que par exemple les fonctions thiols et par exemple les éventuelles fonctions acides carboxyliques, peuvent être partiellement ou totalement neutralisées. The salts of the degradation-inhibiting compounds according to the invention can be obtained for example by their neutralization with the aid of a hydroxide or an alkaline carbonate (preferably a sodium or potassium hydroxide or carbonate), alkaline earth metal or ammonium or with an amine present in the absorbent solution. In this case, the functions having an acidic character, such as for example the thiol functions and for example the possible carboxylic acid functions, may be partially or completely neutralized.
Les sels des composés inhibiteurs de dégradation selon l'invention peuvent être également obtenus par exemple par leur neutralisation à l'aide d'un acide organique ou inorganique. Dans ce cas, c'est au moins un atome d'azote présent sur la molécule qui est protoné. Les composés inhibiteurs de dégradation listés au paragraphe précédent sont particulièrement bien adaptés à la prévention de la dégradation d'amines en solution aqueuse mises en œuvre dans un procédé de captage du C02 contenu dans des fumées de combustion. Pour limiter la dégradation d'une solution absorbante composée d'amines, en particulier d'alcanolamines, par exemple la monoéthanolamine (MEA), en solution aqueuse notamment pour capter le CO2 des fumées de combustion, on peut utiliser de préférence l'un des composés suivants : le 5-méthyl-1 ,3,4-thiadiazoie-2-thiol, le 5-amino-1 ,3,4-thiadiazole-2-thiol, le 5- méthylamino-1 ,3,4-thiadiazole-2-thiol, ainsi que leurs sels tels par exemple les sels de sodium, de potassium ou d'ammonium, comme par exemple le sel de sodium du 5-méthyl-1 ,3,4-thiadiazole-2-thiol, le sel de potassium du 5-méthyl- 1 ,3,4-thiadiazole-2-thiol, le sel d'ammonium du 5-méthyl-1 ,3,4-thiadiazole-2-thiol, le sel de sodium du 5-amino-1 ,3,4-thiadiazole-2-thiol et le sel de potassium du 5- amino-1 ,3,4-thiadiazole-2-thiol. The salts of the degradation inhibitor compounds according to the invention can also be obtained for example by their neutralization using an organic or inorganic acid. In this case, it is at least one nitrogen atom present on the molecule that is protonated. The degradation inhibitor compounds listed in the preceding paragraph are particularly well suited to the prevention of degradation of amines in aqueous solution implemented in a CO 2 capture process contained in combustion fumes. In order to limit the degradation of an absorbent solution composed of amines, in particular alkanolamines, for example monoethanolamine (MEA), in aqueous solution, in particular for capturing the CO2 from the combustion fumes, it is preferable to use one of the following compounds: 5-methyl-1,3,4-thiadiazole-2-thiol, 5-amino-1,3,4-thiadiazole-2-thiol, 5-methylamino-1,3,4-thiadiazole-2-thiol as well as their salts such as, for example, sodium, potassium or ammonium salts, such as, for example, the sodium salt of 5-methyl-1,3,4-thiadiazole-2-thiol, the potassium salt of methyl-1,3,4-thiadiazole-2-thiol, the ammonium salt of 5-methyl-1,3,4-thiadiazole-2-thiol, the sodium salt of 5-amino-1,3; 4-thiadiazole-2-thiol and the potassium salt of 5-amino-1,3,4-thiadiazole-2-thiol.
De préférence, selon l'invention, on utilise le 5-méthyl-1 ,3,4-thiadiazole-2- thiol pour limiter la dégradation d'une aminé, en particulier la MEA, en solution aqueuse mise en œuvre pour désacidifier un effluent gazeux, notamment dans le cadre du captage de C02 contenu dans des fumées de combustion. Preferably, according to the invention, 5-methyl-1,3,4-thiadiazole-2-thiol is used to limit the degradation of an amine, in particular MEA, in aqueous solution used to deacidify an effluent. gaseous, especially in the context of capturing C0 2 contained in combustion fumes.
La solution absorbante selon l'invention comporte une quantité d'additifs inhibiteurs de dégradation définis par la formule générale décrite ci-dessus. La solution absorbante peut comporter un ou plusieurs additifs inhibiteurs de dégradation différents correspondant à ladite formule générale. De plus, dans la solution absorbante, les additifs inhibiteurs de dégradation selon l'invention peuvent être associés à d'autres composés inhibiteurs de dégradation de familles chimiques différentes. Selon l'invention, la solution absorbante comporte entre 5 ppm et 5% poids d'additifs inhibiteurs de dégradation selon l'invention, de préférence de 50 ppm à 2% poids, et une excellente teneur en additifs inhibiteurs de dégradation dans la solution étant comprise entre 100 ppm et 1 % poids. Les exemples présentés ci-après permettent de comparer et d'illustrer les performances des additifs inhibiteurs de dégradation selon l'invention, en terme de réduction de la dégradation des aminés en solution aqueuse, de réduction des émissions de composés de dégradation volatils et de possibilité d'augmenter la concentration en aminés sans augmenter leur dégradation. The absorbent solution according to the invention comprises an amount of degradation inhibiting additives defined by the general formula described above. The absorbent solution may comprise one or more different degradation inhibiting additives corresponding to said general formula. In addition, in the absorbent solution, the degradation inhibitor additives according to the invention may be combined with other degradation inhibitor compounds of different chemical families. According to the invention, the absorbent solution comprises between 5 ppm and 5% by weight of degradation inhibiting additives according to the invention, preferably from 50 ppm to 2% by weight, and an excellent content of degradation inhibiting additives in the solution being between 100 ppm and 1% by weight. The examples presented below make it possible to compare and illustrate the performance of the degradation inhibitor additives according to the invention, in terms of reducing the degradation of amines in aqueous solution, reducing the volatile decomposition of compounds and the possibility of to increase the concentration of amines without increasing their degradation.
EXEMPLE 1 : EXAMPLE 1
Les aminés de la solution absorbante peuvent être dégradées dans une utilisation selon l'invention engendrant une consommation de l'aminé. Cet exemple montre que l'utilisation des additifs inhibiteurs de dégradation des aminés permet de limiter fortement la dégradation desdites aminés. Cet exemple montre en outre que dans le cas de la MEA (monoéthanolamine) l'utilisation des additifs inhibiteurs de dégradation selon l'invention permet l'augmentation de la concentration en aminé de 30% poids, concentration communément utilisée par l'homme du métier, à 40% poids sans augmentation de la dégradation. The amines of the absorbent solution can be degraded in a use according to the invention generating a consumption of the amine. This example shows that the use of amine degradation inhibiting additives greatly limits the degradation of said amines. This example further shows that in the case of MEA (monoethanolamine) the use of degradation inhibitor additives according to the invention allows the increase of amine concentration by 30% by weight, a concentration commonly used by those skilled in the art. at 40% weight without increasing degradation.
Les essais de dégradation d'une aminé en solution aqueuse sont effectués selon le mode opératoire suivant : The degradation tests of an amine in aqueous solution are carried out according to the following procedure:
100g de solution de MEA (monoéthanolamine) 30% ou 40% poids dans l'eau désionisée sont placés dans un réacteur en verre surmonté d'un condenseur pour éviter l'évaporation de l'eau. Le réacteur est chauffé à 80°C dans un bloc chauffant électrique. La solution est agitée à 1000 tours par minute par un barreau aimanté. La présence de contre pales empêche la formation d'un vortex. Un gaz est mis en contact avec la solution à l'aide d'un tube plongeant pendant 7 jours à pression atmosphérique. Selon les essais, on fait varier la nature du gaz mis en contact avec la solution. De même les essais sont conduits soit en absence soit en présence de différents additifs inhibiteurs de dégradation incorporés dans la solution aqueuse d'amine à 0,25% poids. 100 g of MEA solution (monoethanolamine) 30% or 40% by weight in deionized water are placed in a glass reactor surmounted by a condenser to prevent evaporation of the water. The reactor is heated to 80 ° C in an electric heating block. The solution is stirred at 1000 rpm by a magnetic bar. The presence of counter blades prevents the formation of a vortex. A gas is brought into contact with the solution by means of a dip tube for 7 days at atmospheric pressure. According to the tests, the nature of the gas brought into contact with the solution is varied. Similarly, the tests are carried out either in the absence or in the presence of various additives degradation inhibitors incorporated in the aqueous solution of amine at 0.25% by weight.
Lorsque l'essai est conduit uniquement en présence de CO2 et en l'absence d'oxygène, le gaz mis en contact avec la solution est un mélange de 7NI/h d'azote et de 0,033 Nl/h de C02 réalisé dans une chambre de mélange. Dans ce cas, le gaz comporte uniquement du C02 et de l'azote. When the test is conducted only in the presence of CO 2 and in the absence of oxygen, the gas brought into contact with the solution is a mixture of 7NI / h of nitrogen and 0.033 Nl / h of CO 2 produced in a mixing chamber. In this case, the gas comprises only CO 2 and nitrogen.
Lorsque l'essai est conduit en présence de C02 et d'oxygène, le gaz mis en contact avec la solution est un mélange de 7NI/h d'air atmosphérique, c'est-à-dire de l'air ambiant non purifié, et de 0,033 Nl/h de C02 réalisé dans une chambre de mélange. Dans ce cas, le gaz contient du C02, de l'azote et de l'oxygène, la teneur en oxygène dans le gaz étant de 21 % environ. Une analyse par chromatographie en phase gazeuse de la solution ainsi dégradée est réalisée à la fin de l'essai. La méthode chromatographique utilise une colonne polaire, un gaz vecteur, l'hélium, un étalon interne, le triéthylèneglycol et une détection FID (Flame Induced Détection). Cette analyse permet de déterminer la concentration résiduelle de MEA. When the test is conducted in the presence of C0 2 and oxygen, the gas brought into contact with the solution is a mixture of 7NI / h of atmospheric air, that is to say unpurified ambient air and 0.033 Nl / h C0 2 produced in a mixing chamber. In this case, the gas contains CO 2 , nitrogen and oxygen, the oxygen content in the gas being about 21%. A gas chromatographic analysis of the solution thus degraded is carried out at the end of the test. The chromatographic method uses a polar column, a carrier gas, helium, an internal standard, triethylene glycol and FID (Flame Induced Detection) detection. This analysis makes it possible to determine the residual concentration of MEA.
Une vitesse moyenne de dégradation sur la durée de l'essai peut donc être calculée : vitesse _ moyenne _ de _ dégradation = — ] __£_ * masse _de_ solution durée essai An average rate of degradation over the duration of the test can therefore be calculated: average rate of degradation = -] ___ _ mass of solution time test
De même un taux de dégradation peut être calculé Similarly a degradation rate can be calculated
[ \ KA finale  [\ KA final
taux _ de _ dégradation 400  degradation rate 400
[MEA]initiale j [MEA] initial j
Le tableau 1 présente les vitesses moyennes de dégradation de la MEA dans les cas suivants : Table 1 shows the average degradation rates of MEA in the following cases:
• Cas n°1 : MEA 30% poids en présence d'oxygène et sans additif selon l'invention  Case No. 1: MEA 30% by weight in the presence of oxygen and without additive according to the invention
• Cas n°2 : MEA 40% poids en présence d'oxygène et sans additif selon l'invention  Case No. 2: MEA 40% by weight in the presence of oxygen and without additive according to the invention
Figure imgf000016_0001
Figure imgf000016_0001
Tableau 1 : comparaison des vitesses moyennes de dégradation de la MEA 30% et 40% poids en absence d'un additif inhibiteur de dégradation selon l'invention.  Table 1: Comparison of average degradation rates of MEA 30% and 40% by weight in the absence of a degradation inhibitor additive according to the invention.
Le tableau 1 confirme bien qu'une solution aqueuse de MEA 40% poids se dégrade plus vite qu'une solution de MEA 30% poids. Ainsi pour une même durée, la masse de MEA dégradée est plus importante dans le cas d'une solution aqueuse de MEA 40% poids. Table 1 confirms that an aqueous solution of 40 wt% MEA degrades faster than a 30 wt% MEA solution. So for one duration, the degraded MEA mass is greater in the case of an aqueous solution of MEA 40% by weight.
Le tableau 2 donne les taux de dégradation d'une solution aqueuse de MEA (monoéthanolamine) 40% poids, en présence d'un additif inhibiteur de dégradation ou non et soumise à un gaz renfermant de l'azote, du CO2 et contenant ou non de l'oxygène : Table 2 gives the degradation rates of an aqueous solution of MEA (monoethanolamine) 40% by weight, in the presence of a degradation inhibitor additive or not and subjected to a gas containing nitrogen, CO 2 and containing or no oxygen:
• Cas n°2 : en présence d'oxygène et sans additif selon l'invention Case # 2: in the presence of oxygen and without additive according to the invention
• Cas n°3 : sans oxygène et sans additif selon l'inventionCase # 3: without oxygen and without additive according to the invention
• Cas n°4 : en présence d'oxygène et en présence d'un additif selon l'invention, le 5-méthyl-1 ,3,4-thiadiazole-2-thiol Case No. 4: in the presence of oxygen and in the presence of an additive according to the invention, 5-methyl-1,3,4-thiadiazole-2-thiol
Figure imgf000017_0001
Figure imgf000017_0001
Tableau 2 : comparaison des taux de dégradation de la MEA 40% poids obtenus dans l'eau à 80°C dans les différents cas.  Table 2: Comparison of degradation rates of the MEA 40% weight obtained in water at 80 ° C in the different cases.
Il apparaît clairement que : It is clear that:
1. la solution de MEA n'est pas dégradée en présence du seul CO2 en l'absence d'oxygène 1. the MEA solution is not degraded in the presence of only CO 2 in the absence of oxygen
2. la dégradation de la MEA est attribuable à la présence d'oxygène 2. The degradation of MEA is attributable to the presence of oxygen
3. en présence d'additifs selon l'invention, la dégradation de la MEA est ramenée au même niveau que celle constatée en l'absence d'oxygène, c'est-à-dire considérée comme nulle car inférieure à l'incertitude de la mesure qui est de 3%. 3. in the presence of additives according to the invention, the degradation of the MEA is brought to the same level as that observed in the absence of oxygen, that is to say considered as zero because lower than the uncertainty of the measure which is 3%.
En conclusion, les additifs selon l'invention combattent efficacement l'effet de l'oxygène sur la dégradation de la MEA. Il apparaît clairement qu'en présence d'un additif selon l'invention, la dégradation de la MEA à 40 % poids dans l'eau peut être considérée comme nulle car inférieure à l'incertitude de la mesure qui est de 3%. In conclusion, the additives according to the invention effectively combat the effect of oxygen on the degradation of MEA. It is clear that in the presence of an additive according to the invention, the degradation of MEA at 40% by weight in water can be considered as zero because lower than the uncertainty of the measure which is 3%.
Ainsi, dans le cas de la MEA, les additifs selon l'invention permettent d'augmenter la concentration en aminé communément utilisée par l'homme du métier sans augmenter la dégradation de l'aminé. Thus, in the case of MEA, the additives according to the invention make it possible to increase the concentration of amine commonly used by those skilled in the art without increasing the degradation of the amine.
EXEMPLE 2 : EXAMPLE 2
En particulier, les aminés peuvent être dégradées par l'oxygène engendrant la formation de produits volatils, qui sont entraînés dans les effluents gazeux du procédé. Ainsi, par exemple dans le cas du traitement de fumées en post-combustion dans un procédé utilisant une solution aqueuse de MEA des quantités importantes d'ammoniac sont formées. L'ammoniac ainsi formé est entraîné dans l'atmosphère avec les fumées traitées ce qui pose des problèmes quant à la protection de l'environnement. In particular, the amines can be degraded by the oxygen generating the formation of volatile products, which are entrained in the gaseous effluents of the process. Thus, for example in the case of post-combustion flue gas treatment in a process using aqueous MEA solution, large amounts of ammonia are formed. The ammonia thus formed is entrained in the atmosphere with the treated fumes, which poses problems as regards the protection of the environment.
Cet exemple montre que l'utilisation des additifs inhibiteurs de dégradation des aminés permet de limiter fortement la formation de produits volatils. Cet exemple montre en outre que dans le cas de la MEA (monoéthanolamine) l'utilisation des additifs inhibiteurs de dégradation selon l'invention permet l'augmentation de la concentration en aminé de 30% poids, concentration communément utilisée par l'homme du métier, à 40% poids sans augmenter la formation de produits volatils. This example shows that the use of amine degradation inhibiting additives greatly limits the formation of volatile products. This example further shows that in the case of MEA (monoethanolamine) the use of degradation inhibitor additives according to the invention allows the increase of amine concentration by 30% by weight, a concentration commonly used by those skilled in the art. at 40% weight without increasing the formation of volatile products.
Cet exemple donne les résultats obtenus avec une solution aqueuse de MEA à 40% poids. This example gives the results obtained with an aqueous solution of MEA at 40% by weight.
La figure 1 présente un suivi de la concentration en ammoniac dans le gaz sortant du réacteur dans les cas 2 et 4 définis dans l'exemple 1. [A] correspond à la concentration en ammoniac en ppm volume dans le gaz de sortie du réacteur, t représente le temps exprimé en jours. Les cas 2 et 4 sont représentés respectivement par la courbe 2 avec des ronds noirs et la courbe 4 avec des losanges blancs. FIG. 1 shows a follow-up of the concentration of ammonia in the gas leaving the reactor in cases 2 and 4 defined in example 1. [A] corresponds to the concentration of ammonia in ppm volume in the exit gas of the reactor, t represents the time expressed in days. Cases 2 and 4 are respectively represented by curve 2 with black circles and curve 4 with white rhombuses.
La concentration en ammoniac dans le gaz sortant du réacteur est déterminée par une analyse en ligne par spectrométrie Infra-Rouge à Transformée de Fourrier.  The ammonia concentration in the gas leaving the reactor is determined by an online Fourier Transform Infra-Red spectrometry analysis.
Dans le cas des additifs inhibiteur de dégradation selon l'invention, la teneur en NH3 est inférieure à 10ppm pendant toute la durée du test alors qu'elle dépasse rapidement les 2000ppm sans additif inhibiteur de dégradation. Il apparaît clairement qu'en présence d'un additif selon l'invention, les émissions d'ammoniac liées à la dégradation de la MEA à 40 % poids dans l'eau sont considérablement réduites. Cet exemple montre donc bien, dans le cas de la MEA, que les additifs selon l'invention permettent d'augmenter la concentration en aminé communément utilisée par l'homme du métier sans augmenter les émissions d'ammoniac. In the case of degradation inhibitor additives according to the invention, the NH 3 content is less than 10 ppm for the duration of the test whereas it rapidly exceeds 2000 ppm without additive degradation inhibitor. It is clear that in the presence of an additive according to the invention, the ammonia emissions related to the degradation of MEA at 40% by weight in water are considerably reduced. This example thus clearly shows, in the case of MEA, that the additives according to the invention make it possible to increase the concentration of amine commonly used by those skilled in the art without increasing the ammonia emissions.
Par conséquent, dans un procédé industriel utilisant une solution absorbante contenant des additifs inhibiteurs de dégradation selon l'invention, les émissions de composés volatils en tête d'absorbeur seront bien moindres qu'en absence d'additifs inhibiteurs de dégradation même si la concentration en aminé est augmentée par rapport à la concentration communément utilisée par l'homme du métier.  Therefore, in an industrial process using an absorbent solution containing degradation inhibitor additives according to the invention, the emissions of volatile compounds at the absorber head will be much lower than in the absence of degradation inhibitor additives even if the concentration of amine is increased relative to the concentration commonly used by those skilled in the art.

Claims

REVENDICATIONS
1) Solution absorbante pour absorber les composés acides d'un effluent gazeux, ladite solution comportant : 1) Absorbent solution for absorbing the acidic compounds of a gaseous effluent, said solution comprising:
a) au moins une aminé,  a) at least one amine,
b) de l'eau,  (b) water,
c) au moins un composé inhibiteur de dégradation pour limiter la dégradation de ladite aminé, le composé inhibiteur répondant à la formule :
Figure imgf000020_0001
c) at least one degradation inhibiting compound for limiting the degradation of said amine, the inhibiting compound having the formula:
Figure imgf000020_0001
dans laquelle R est choisi parmi :  wherein R is selected from:
• un atome d'hydrogène,  • a hydrogen atom,
• un radical -R1-R2 dans lequel Ri est choisi parmi un atome d'oxygène et un groupement hydrocarboné comprenant 1 à 12 atomes de carbone et dans lequel R2 est un groupement hydrocarboné comprenant 1 à 12 atomes de carbone, A radical -R 1 -R 2 in which R 1 is chosen from an oxygen atom and a hydrocarbon group comprising 1 to 12 carbon atoms and in which R 2 is a hydrocarbon group comprising 1 to 12 carbon atoms,
• un groupement -NR3R4 dans lequel R3 et R4 sont indépendamment choisis parmi un atome d'hydrogène et un groupement hydrocarboné comportant entre 1 et 20 atomes de carbone, A group -NR3R4 in which R3 and R4 are independently chosen from a hydrogen atom and a hydrocarbon group containing between 1 and 20 carbon atoms,
dans laquelle X est choisi parmi :  wherein X is selected from:
• un atome d'hydrogène,  • a hydrogen atom,
• un groupement hydrocarboné comportant entre 1 et 20 atomes de carbone,  A hydrocarbon group comprising between 1 and 20 carbon atoms,
• un élément alcalin,  • an alkaline element,
• un élément alcalino-terreux,  • an alkaline earth element,
• un métal monovalent ou multivalent,  • a monovalent or multivalent metal,
• un cation ammonium NH4 + ou résultant de la protonation d'une fonction aminé, An ammonium NH 4 + cation or resulting from the protonation of an amine function,
• un cation phosphonium. 2) Solution absorbante selon la revendication 1 , dans laquelle au moins un des radicaux R2, R3, R4 et X est un groupement hydrocarboné comportant, en outre, au moins un hétéroatome. 3) Solution absorbante selon la revendication 2, dans laquelle les radicauxA phosphonium cation. 2) Absorbent solution according to claim 1, wherein at least one of R2, R3, R4 and X is a hydrocarbon group further comprising at least one heteroatom. 3) Absorbent solution according to claim 2, wherein the radicals
R3 et R4 sont reliés entre eux par une liaison covalente pour former un hétérocycle comportant entre 5 et 8 atomes. R3 and R4 are linked together by a covalent bond to form a heterocycle having 5 to 8 atoms.
4) Solution absorbante selon l'une des revendications 1 à 3, dans laquelle R2 est un groupement hydrocarboné comportant, en outre, au moins un halogène. 4) Absorbent solution according to one of claims 1 to 3, wherein R2 is a hydrocarbon group further comprising at least one halogen.
5) Solution absorbante selon l'une des revendications précédentes, dans laquelle la solution comporte entre 10% et 99% poids d'amine, entre 1 % et 90% poids d'eau et entre 5 ppm et 5% poids de composé inhibiteur de dégradation. 5) Absorbent solution according to one of the preceding claims, wherein the solution comprises between 10% and 99% by weight of amine, between 1% and 90% by weight of water and between 5 ppm and 5% by weight of degradation.
6) Solution absorbante selon l'une des revendications précédentes, dans laquelle le composé inhibiteur de dégradation est choisi parmi le groupe contenant le 5-méthyl-1 ,3,4-thiadiazole-2-thiol, le 5-amino-1 ,3,4-thiadiazole-2-thiol, le 5- méthylamino-1 ,3,4-thiadiazole-2-thiol, le 2-amino-5-(méthylthio)-1 ,3,4-thiadiazole, le 2-amino-5-(éthylthio)-1 ,3,4-thiadiazole, un sel du 5-méthyl-1 ,3,4-thiadiazole-2- thiol, un sel du 5-amino-1 ,3,4-thiadiazole-2-thiol, un sel du 5-méthylamino-1 ,3,4- thiadiazole-2-thiol, un sel du 2-amino-5-(méthylthio)-1 ,3,4-thiadiazole et un sel du 2-amino-5-(éthylthio)-1 ,3,4-thiadiazole. 7) Solution absorbante selon l'une des revendications précédentes, dans laquelle l'aminé est choisie parmi le groupe contenant : la N,N,N',N',N"-pentaméthyldiéthylènetriamine, la pipérazine, la monoéthanolamine, la diéthanolamine, la méthyldiéthanolamine, la diisopropanolamine, la diglycolamine, un sel de la glycine et un sel de la taurine. 6) Absorbent solution according to one of the preceding claims, wherein the degradation inhibiting compound is selected from the group containing 5-methyl-1,3,4-thiadiazole-2-thiol, 5-amino-1,3 4-thiadiazole-2-thiol, 5-methylamino-1,3,4-thiadiazole-2-thiol, 2-amino-5- (methylthio) -1,4,4-thiadiazole, 2-amino 5- (ethylthio) -1,3,4-thiadiazole, a salt of 5-methyl-1,3,4-thiadiazole-2-thiol, a salt of 5-amino-1,3,4-thiadiazole-2- thiol, a salt of 5-methylamino-1,3,4-thiadiazole-2-thiol, a salt of 2-amino-5- (methylthio) -1,3,4-thiadiazole and a salt of 2-amino-5 - (ethylthio) -1,4,4-thiadiazole. 7) Absorbent solution according to one of the preceding claims, wherein the amine is selected from the group containing: N, N, N ', N', N "-pentamethyldiethylenetriamine, piperazine, monoethanolamine, diethanolamine, methyldiethanolamine, diisopropanolamine, diglycolamine, a salt of glycine and a salt of taurine.
8) Solution absorbante selon l'une des revendications précédentes, dans laquelle l'aminé est la monoéthanolamine et dans laquelle le composé inhibiteur de dégradation est le 5-méthyl-1 ,3,4-thiadiazole-2-thiol. 9) Solution absorbante selon l'une des revendications 7 et 8, comportant au moins 39% poids de monoéthanolamine. The absorbent solution according to one of the preceding claims, wherein the amine is monoethanolamine and wherein the degradation-inhibiting compound is 5-methyl-1,3,4-thiadiazole-2-thiol. 9) Absorbent solution according to one of claims 7 and 8, comprising at least 39% by weight of monoethanolamine.
10) Procédé pour absorber des composés acides contenus dans un effluent gazeux, dans lequel on met en contact l'effluent gazeux avec une solution aqueuse comportant au moins une amine, et dans lequel on contrôle la dégradation de ladite amine en introduisant dans ladite solution aqueuse au moins un composé inhibiteur de dégradation répondant à la formule générale suivante :
Figure imgf000022_0001
10) Process for absorbing acidic compounds contained in a gaseous effluent, in which the gaseous effluent is brought into contact with an aqueous solution containing at least one amine, and wherein the degradation of said amine is controlled by introducing into said aqueous solution at least one degradation inhibiting compound having the following general formula:
Figure imgf000022_0001
dans laquelle R est choisi parmi :  wherein R is selected from:
• un atome d'hydrogène,  • a hydrogen atom,
• un radical -R1-R2 dans lequel Ri est choisi parmi un atome d'oxygène et un groupement hydrocarboné comprenant 1 à 12 atomes de carbone et dans lequel R2 est un groupement hydrocarboné comprenant 1 à 12 atomes de carbone, A radical -R 1 -R 2 in which R 1 is chosen from an oxygen atom and a hydrocarbon group comprising 1 to 12 carbon atoms and in which R 2 is a hydrocarbon group comprising 1 to 12 carbon atoms,
• un groupement -NR3R4 dans lequel R3 et R4 sont indépendamment choisis parmi un atome d'hydrogène et un groupement hydrocarboné comportant entre 1 et 20 atomes de carbone, A group -NR3R4 in which R3 and R4 are independently chosen from a hydrogen atom and a hydrocarbon group containing between 1 and 20 carbon atoms,
dans laquelle X est choisi parmi :  wherein X is selected from:
• un atome d'hydrogène,  • a hydrogen atom,
• un groupement hydrocarboné comportant entre 1 et 20 atomes de carbone,  A hydrocarbon group comprising between 1 and 20 carbon atoms,
• un élément alcalin,  • an alkaline element,
• un élément alcalino-terreux,  • an alkaline earth element,
• un métal monovalent ou multivalent,  • a monovalent or multivalent metal,
• un cation ammonium NH4 + ou résultant de la protonation d'une fonction amine, An ammonium NH 4 + cation or resulting from the protonation of an amine function,
• un cation phosphonium. 11) Procédé selon la revendication 11 , dans lequel la solution aqueuse est mise en oeuvre pour absorber des composés acides contenus dans l'un des effluents du groupe contenant le gaz naturel, les fumées de combustion, les gaz de synthèse, les gaz de raffinerie, les gaz obtenus en queue du procédé Claus, les gaz de fermentation de biomasse, les gaz de cimenterie et les fumées d'incinérateur. A phosphonium cation. 11) Process according to claim 11, wherein the aqueous solution is used to absorb acidic compounds contained in one of the effluents of the group containing natural gas, combustion fumes, synthesis gas, refinery gas. , tail gas from the Claus process, biomass fermentation gas, cement gas and incinerator fumes.
12) Procédé selon la revendication 12, dans lequel l'effluent gazeux comporte au moins 500ppm volumique d'oxygène. 12) The method of claim 12, wherein the gaseous effluent comprises at least 500ppm oxygen volume.
13) Procédé selon l'une des revendications 11 à 13, dans lequel on introduit dans la solution aqueuse au moins un composé inhibiteur de dégradation choisi parmi le groupe contenant : le 5-méthyl-1 ,3,4-thiadiazole-2-thiol, le 5-amino-1 ,3,4- thiadiazole-2-thiol, le 5-méthylamino-1 ,3,4-thiadiazole-2-thiol, le 2-amino-5- (méthylthio)-1 ,3,4-thiadiazole, le 2-amino-5-(éthylthio)-1 ,3,4-thiadiazole, un sel du 5-méthyl-1 ,3,4-thiadiazole-2-thiol, un sel du 5-amino-1 ,3,4-thiadiazole-2-thiol, un sel du 5-méthylamino-1 ,3,4-thiadiazole-2-thiol, un sel du 2-amino-5-(méthylthio)- 1 ,3,4-thiadiazole et un sel du 2-amino-5-(éthylthio)-1 ,3,4-thiadiazole. 14) Procédé selon la revendication 11 , dans lequel pour limiter la dégradation de la monoéthanolamine en solution aqueuse mise en œuvre pour capter le CO2 contenu dans des fumées de combustion, on ajoute dans la solution aqueuse au moins un composé inhibiteur de dégradation suivant : le 5- méthyl-1 ,3,4-thiadiazole-2-thiol. 13) Method according to one of claims 11 to 13, wherein is introduced into the aqueous solution at least one degradation inhibiting compound selected from the group containing: 5-methyl-1,3,4-thiadiazole-2-thiol 5-amino-1,3,4-thiadiazole-2-thiol, 5-methylamino-1,3,4-thiadiazole-2-thiol, 2-amino-5- (methylthio) -1,3, 4-thiadiazole, 2-amino-5- (ethylthio) -1,3,4-thiadiazole, a salt of 5-methyl-1,3,4-thiadiazole-2-thiol, a salt of 5-amino-1 3,4-thiadiazole-2-thiol, a salt of 5-methylamino-1,3,4-thiadiazole-2-thiol, a salt of 2-amino-5- (methylthio) -1,3,4-thiadiazole and a salt of 2-amino-5- (ethylthio) -1,3,4-thiadiazole. 14) Process according to claim 11, wherein to limit the degradation of the monoethanolamine in aqueous solution implemented to capture the CO2 contained in combustion fumes, is added in the aqueous solution at least one degradation inhibitor compound according to: 5-methyl-1,3,4-thiadiazole-2-thiol.
PCT/FR2011/000275 2010-05-20 2011-05-04 Absorbent solution containing a thiadiazole-derivative degradation inhibitor and its use in an absorption process WO2011144823A1 (en)

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Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4935157A (en) * 1989-06-05 1990-06-19 R. T. Vanderbilt Company, Inc. 2-hydroxy-1,3,4-thiadiazoles and lubricating compositions containing same
DE4027300A1 (en) * 1990-08-29 1992-03-05 Linde Ag Desulphurisation of gases - by scrubbing with nitrogen contg. heterocyclic solvent
US5686016A (en) 1995-10-10 1997-11-11 Veldman; Ray R. Oxygen scavenging solutions for reducing corrosion by heat stable amine salts
FR2820430A1 (en) 2001-02-02 2002-08-09 Inst Francais Du Petrole PROCESS FOR DEACIDIFYING A GAS WITH WASHING OF DESORBED HYDROCARBONS DURING THE REGENERATION OF THE SOLVENT
EP1582250A2 (en) * 2004-03-09 2005-10-05 Basf Aktiengesellschaft Absorbent with improved ocidation resistance and process for deacidifying fluid fluxes
US7056482B2 (en) 2003-06-12 2006-06-06 Cansolv Technologies Inc. Method for recovery of CO2 from gas streams
WO2008144501A2 (en) * 2007-05-17 2008-11-27 Advanced Technology Materials Inc. New antioxidants for post-cmp cleaning formulations
WO2009156619A2 (en) * 2008-06-27 2009-12-30 Ifp Absorbing solution containing a thiadiazole-derived degradation inhibitor and method for limiting the degradation of an absorbing solution

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4935157A (en) * 1989-06-05 1990-06-19 R. T. Vanderbilt Company, Inc. 2-hydroxy-1,3,4-thiadiazoles and lubricating compositions containing same
DE4027300A1 (en) * 1990-08-29 1992-03-05 Linde Ag Desulphurisation of gases - by scrubbing with nitrogen contg. heterocyclic solvent
US5686016A (en) 1995-10-10 1997-11-11 Veldman; Ray R. Oxygen scavenging solutions for reducing corrosion by heat stable amine salts
FR2820430A1 (en) 2001-02-02 2002-08-09 Inst Francais Du Petrole PROCESS FOR DEACIDIFYING A GAS WITH WASHING OF DESORBED HYDROCARBONS DURING THE REGENERATION OF THE SOLVENT
US7056482B2 (en) 2003-06-12 2006-06-06 Cansolv Technologies Inc. Method for recovery of CO2 from gas streams
EP1582250A2 (en) * 2004-03-09 2005-10-05 Basf Aktiengesellschaft Absorbent with improved ocidation resistance and process for deacidifying fluid fluxes
WO2008144501A2 (en) * 2007-05-17 2008-11-27 Advanced Technology Materials Inc. New antioxidants for post-cmp cleaning formulations
WO2009156619A2 (en) * 2008-06-27 2009-12-30 Ifp Absorbing solution containing a thiadiazole-derived degradation inhibitor and method for limiting the degradation of an absorbing solution

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