초록 ▼

The combustion fume flowing in through line 1 is decarbonated by contacting with a solvent in column C2. The solvent laden with carbon dioxide is regenerated in zone R. The purified fume discharged through line 9 comprises part of the solvent. The method allows to extract the solvent contained in th

The combustion fume flowing in through line 1 is decarbonated by contacting with a solvent in column C2. The solvent laden with carbon dioxide is regenerated in zone R. The purified fume discharged through line 9 comprises part of the solvent. The method allows to extract the solvent contained in the purified fume. The purified fume is contacted in zone ZA with a non-aqueous ionic liquid of general formula Q+ A-; Q+ designates an ammonium, phosphonium and/or sulfonium cation, and A- an anion likely to form a liquid salt. The solvent-depleted purified fume is discharged through line 17. The solvent-laden ionic liquid is regenerated by heating in evaporation device DE. The solvent separated from the ionic liquid in device DE is recycled.

대표청구항 ▼

The invention claimed is: 1. A method of treating a combustion fume comprising nitrogen and at least one of the acid compounds as follows: carbon oxides, nitrogen oxides and sulfur oxides, wherein the following stages are carried out: a) contacting the fume with a solvent capturing the acid compoun

The invention claimed is: 1. A method of treating a combustion fume comprising nitrogen and at least one of the acid compounds as follows: carbon oxides, nitrogen oxides and sulfur oxides, wherein the following stages are carried out: a) contacting the fume with a solvent capturing the acid compounds so as to obtain, on the one hand, a solvent-comprising purified fume and, on the other hand, a solvent laden with acid compounds, and b) contacting the solvent-comprising purified fume obtained in stage a) with a non-aqueous ionic liquid so as to obtain a solvent-depleted purified fume and a solvent-laden ionic liquid, the ionic liquid having as general formula Q+ A-; Q+ designating an ammonium, phosphonium and/or sulfonium cation, and A- an anion likely to form a liquid salt. 2. A method as claimed in claim 1, wherein the following stage is also carried out: c) regenerating the solvent-laden ionic liquid so as to recover, on the one hand, a solvent-depleted ionic liquid and, on the other hand, a solvent-comprising effluent. 3. A method as claimed in claim 2 wherein, in stage c), the solvent-laden ionic liquid is heated to evaporate the solvent-comprising effluent. 4. A method as claimed in claim 2 wherein, prior to stage a), the fume is contacted with the solvent-comprising effluent obtained in stage c). 5. A method as claimed in claim 1, wherein the solvent laden with acid compounds obtained in stage a) is regenerated by expansion and/or by heating. 6. A method as claimed in claim 1, wherein prior to stage b), the purified fume obtained in stage a) is cooled in order to condense part of the solvent. 7. A method as claimed in claim 1, wherein the solvent comprises at least one compound selected from the group consisting of glycols, ethers, glycol ethers, alcohols, sulfolane, N-methylpyrrolidone,propylene carbonate, ionic liquids, amines, alkanolamines, amino-acids, amides, ureas, phosphates, carbonates, alkali metal borates, and water. 8. A method as claimed in claim 7, wherein the solvent contains water. 9. A method as claimed in claim 1, wherein anion A- is selected from the group consisting of the ions halogenides, nitrate, sulfate, phosphate, acetate, halogenoacetates, tetrafluoroborate, tetrachloroborate, hexafluoro-phosphate, hexafluoroantimonate, fluorosulfonate, alkylsulfonates, perfluoro-alkylsulfonates, bis(perfluoroalkylsulfonyl) amidides, tris-trifluoromethanesulfonyl methylide of formula C(CF3SO2)3-, alkylsulfates, arenesulfates, arenesulfonates, tetraphenylborate and tetraphenylborates whose aromatic rings are substituted. 10. A method as claimed in claim 1, wherein cation Q+ has one of the following general formulas: [NR1R2R3R4]+ excluding NH4��, [PR1R2R3R4]+, [R1R2N═CR3R4]+ and [R1R2P═CR3R4]+ where R1, R2, R3 and R4 represent hydrogen or a hydrocarbyl having 1 to 30 carbon atoms. 11. A method as claimed in claim 1, wherein cation Q+ is derived from a nitrogen and/or phosphorus heterocycle comprising 1, 2 or 3 nitrogen and/or phosphorus atoms, the heterocycle consisting of 4 to 10 carbon atoms. 12. A method as claimed in claim 1, wherein cation Q+ has one of the general formulas as follows: R1R2N+═CR3-R5-R3 C═N+R1R2 and R1R2P+═CR3-R5-R3 C═P+R1R2, where R1, R2 et R3 represent hydrogen or a hydrocarbyl remainder having 1 to 30 carbon atoms and where R5 represents an alkylene or phenylene remainder. 13. A method as claimed in claim 1, wherein cation Q+ is selected from the group consisting of N-butylpyridinium, N-ethylpyridinium, pyridinium, ethyl-3-methyl-1-imidazolium, butyl-3-methyl-1-imidazolium, hexyl-3-methyl-1-imidazolium, butyl-3-dimethyl-1,2-imidazolium, diethyl-pyrazolium, N-butyl-N-methyl-pyrro-lidinium, trimethylphenylammonium, tetrabutylphosphonium, and tributyltetradecyl-phosphonium. 14. A method as claimed in claim 1, wherein cation Q+ is of general formula [SR1R2R3]+, where R1, R2 and R3 represent each a hydrocarbyl remainder having 1 to 12 carbon atoms. 15. A method as claimed in claim 1, wherein the ionic liquid is selected from the group consisting of N-butyl-pyridinium hexafluorophosphate, N-ethyl-pyridinium tetrafluoroborate, pyridinium fluorosulfonate, butyl-3-methyl-1-imidazolium tetrafluoroborate, butyl-3-methyl-1-imidazolium bis-trifluoromethane-sulfonyl amidide, triethylsulfonium bis-trifluoromethane-sulfonyl amidide, butyl-3-methyl-1-imidazolium hexafluoro-antimonate, butyl-3-methyl-1-imidazolium hexa-fluorophosphate, butyl-3-methyl-1-imidazolium trifluoroacetate, butyl-3-methyl-1-imidazolium trifluoromethylsulfonate, butyl-3-methyl-1-imidazolium bis(trifluoro-methylsulfonyl)amidide, trimethyl-phenylammonium hexafluorophosphate, and tetrabutylphosphonium tetrafluoroborate.