EP2513035A1 - Extraction de toluène acide d'eaux usées dinitrotoluène - Google Patents
Extraction de toluène acide d'eaux usées dinitrotoluèneInfo
- Publication number
- EP2513035A1 EP2513035A1 EP10793218A EP10793218A EP2513035A1 EP 2513035 A1 EP2513035 A1 EP 2513035A1 EP 10793218 A EP10793218 A EP 10793218A EP 10793218 A EP10793218 A EP 10793218A EP 2513035 A1 EP2513035 A1 EP 2513035A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- extraction
- mixture
- sulfuric acid
- nitration
- wastewater
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 239000002351 wastewater Substances 0.000 title claims abstract description 91
- 238000000605 extraction Methods 0.000 title claims abstract description 78
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 title claims description 120
- 239000002253 acid Substances 0.000 title description 12
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims abstract description 106
- 238000000034 method Methods 0.000 claims abstract description 91
- 239000000203 mixture Substances 0.000 claims abstract description 50
- 238000006396 nitration reaction Methods 0.000 claims abstract description 48
- 230000002378 acidificating effect Effects 0.000 claims abstract description 11
- 239000008346 aqueous phase Substances 0.000 claims abstract description 11
- 150000001491 aromatic compounds Chemical class 0.000 claims abstract description 11
- 125000003118 aryl group Chemical group 0.000 claims abstract description 10
- 239000012074 organic phase Substances 0.000 claims abstract description 9
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 claims description 30
- 230000020477 pH reduction Effects 0.000 claims description 28
- 239000007789 gas Substances 0.000 claims description 21
- UHOVQNZJYSORNB-UHFFFAOYSA-N monobenzene Natural products C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 claims description 19
- 239000002699 waste material Substances 0.000 claims description 14
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 12
- 229910017604 nitric acid Inorganic materials 0.000 claims description 12
- 239000012071 phase Substances 0.000 claims description 10
- 238000005121 nitriding Methods 0.000 claims description 7
- MVPPADPHJFYWMZ-UHFFFAOYSA-N chlorobenzene Chemical compound ClC1=CC=CC=C1 MVPPADPHJFYWMZ-UHFFFAOYSA-N 0.000 claims description 6
- 238000011084 recovery Methods 0.000 claims description 6
- 238000010626 work up procedure Methods 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 claims description 4
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 claims description 3
- 239000008096 xylene Substances 0.000 claims description 3
- OCJBOOLMMGQPQU-UHFFFAOYSA-N 1,4-dichlorobenzene Chemical compound ClC1=CC=C(Cl)C=C1 OCJBOOLMMGQPQU-UHFFFAOYSA-N 0.000 claims description 2
- 229940117389 dichlorobenzene Drugs 0.000 claims description 2
- 238000004821 distillation Methods 0.000 claims description 2
- 125000001997 phenyl group Chemical group [H]C1=C([H])C([H])=C(*)C([H])=C1[H] 0.000 claims description 2
- 239000007858 starting material Substances 0.000 claims 1
- 150000001875 compounds Chemical class 0.000 abstract description 3
- 239000008130 destillate Substances 0.000 abstract 1
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 18
- 230000007935 neutral effect Effects 0.000 description 14
- -1 Aromatic nitro compounds Chemical class 0.000 description 13
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 11
- LQNUZADURLCDLV-UHFFFAOYSA-N nitrobenzene Chemical compound [O-][N+](=O)C1=CC=CC=C1 LQNUZADURLCDLV-UHFFFAOYSA-N 0.000 description 10
- 150000005338 nitrobenzoic acids Chemical class 0.000 description 10
- 229910002092 carbon dioxide Inorganic materials 0.000 description 9
- 125000000449 nitro group Chemical group [O-][N+](*)=O 0.000 description 9
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 8
- 229910002089 NOx Inorganic materials 0.000 description 8
- 229910052799 carbon Inorganic materials 0.000 description 8
- 238000000926 separation method Methods 0.000 description 8
- GQPLMRYTRLFLPF-UHFFFAOYSA-N nitrous oxide Inorganic materials [O-][N+]#N GQPLMRYTRLFLPF-UHFFFAOYSA-N 0.000 description 7
- IOVCWXUNBOPUCH-UHFFFAOYSA-M Nitrite anion Chemical compound [O-]N=O IOVCWXUNBOPUCH-UHFFFAOYSA-M 0.000 description 6
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- RBXVOQPAMPBADW-UHFFFAOYSA-N nitrous acid;phenol Chemical class ON=O.OC1=CC=CC=C1 RBXVOQPAMPBADW-UHFFFAOYSA-N 0.000 description 6
- 150000003839 salts Chemical class 0.000 description 6
- 239000000243 solution Substances 0.000 description 6
- JINHZAXMOALKLT-UHFFFAOYSA-N 1,6-dimethyl-5-nitrocyclohexa-2,4-dien-1-ol Chemical class [N+](=O)([O-])C=1C(C(C=CC1)(C)O)C JINHZAXMOALKLT-UHFFFAOYSA-N 0.000 description 5
- DYSXLQBUUOPLBB-UHFFFAOYSA-N 2,3-dinitrotoluene Chemical compound CC1=CC=CC([N+]([O-])=O)=C1[N+]([O-])=O DYSXLQBUUOPLBB-UHFFFAOYSA-N 0.000 description 5
- ZPTVNYMJQHSSEA-UHFFFAOYSA-N 4-nitrotoluene Chemical compound CC1=CC=C([N+]([O-])=O)C=C1 ZPTVNYMJQHSSEA-UHFFFAOYSA-N 0.000 description 5
- 238000004458 analytical method Methods 0.000 description 5
- 238000002156 mixing Methods 0.000 description 5
- 238000001139 pH measurement Methods 0.000 description 5
- 238000005406 washing Methods 0.000 description 5
- WDCYWAQPCXBPJA-UHFFFAOYSA-N 1,3-dinitrobenzene Chemical compound [O-][N+](=O)C1=CC=CC([N+]([O-])=O)=C1 WDCYWAQPCXBPJA-UHFFFAOYSA-N 0.000 description 4
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 4
- 239000006096 absorbing agent Substances 0.000 description 4
- 239000012043 crude product Substances 0.000 description 4
- 239000012535 impurity Substances 0.000 description 4
- 230000000802 nitrating effect Effects 0.000 description 4
- 238000000746 purification Methods 0.000 description 4
- 239000002904 solvent Substances 0.000 description 4
- 239000012485 toluene extract Substances 0.000 description 4
- MGWGWNFMUOTEHG-UHFFFAOYSA-N 4-(3,5-dimethylphenyl)-1,3-thiazol-2-amine Chemical compound CC1=CC(C)=CC(C=2N=C(N)SC=2)=C1 MGWGWNFMUOTEHG-UHFFFAOYSA-N 0.000 description 3
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 3
- 230000002411 adverse Effects 0.000 description 3
- 239000001569 carbon dioxide Substances 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- JCXJVPUVTGWSNB-UHFFFAOYSA-N nitrogen dioxide Inorganic materials O=[N]=O JCXJVPUVTGWSNB-UHFFFAOYSA-N 0.000 description 3
- 238000012545 processing Methods 0.000 description 3
- 238000005201 scrubbing Methods 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonium chloride Substances [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 description 2
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- BVKZGUZCCUSVTD-UHFFFAOYSA-M Bicarbonate Chemical compound OC([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-M 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-N ammonia Natural products N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- 235000011114 ammonium hydroxide Nutrition 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 239000002585 base Substances 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 239000007795 chemical reaction product Substances 0.000 description 2
- 150000001896 cresols Chemical class 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 150000002828 nitro derivatives Chemical class 0.000 description 2
- 229960001730 nitrous oxide Drugs 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 238000005191 phase separation Methods 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- 229910000029 sodium carbonate Inorganic materials 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 238000001149 thermolysis Methods 0.000 description 2
- BYFNZOKBMZKTSC-UHFFFAOYSA-N 1,3-dimethyl-5-nitrobenzene Chemical compound CC1=CC(C)=CC([N+]([O-])=O)=C1 BYFNZOKBMZKTSC-UHFFFAOYSA-N 0.000 description 1
- BFCFYVKQTRLZHA-UHFFFAOYSA-N 1-chloro-2-nitrobenzene Chemical compound [O-][N+](=O)C1=CC=CC=C1Cl BFCFYVKQTRLZHA-UHFFFAOYSA-N 0.000 description 1
- GAKLFAZBKQGUBO-UHFFFAOYSA-N 2-methyl-3-nitrophenol Chemical class CC1=C(O)C=CC=C1[N+]([O-])=O GAKLFAZBKQGUBO-UHFFFAOYSA-N 0.000 description 1
- INYDMNPNDHRJQJ-UHFFFAOYSA-N 3,4-dinitrotoluene Chemical compound CC1=CC=C([N+]([O-])=O)C([N+]([O-])=O)=C1 INYDMNPNDHRJQJ-UHFFFAOYSA-N 0.000 description 1
- OTLNPYWUJOZPPA-UHFFFAOYSA-N 4-nitrobenzoic acid Chemical compound OC(=O)C1=CC=C([N+]([O-])=O)C=C1 OTLNPYWUJOZPPA-UHFFFAOYSA-N 0.000 description 1
- ZIIGSRYPZWDGBT-UHFFFAOYSA-N 610-30-0 Chemical compound OC(=O)C1=CC=C([N+]([O-])=O)C=C1[N+]([O-])=O ZIIGSRYPZWDGBT-UHFFFAOYSA-N 0.000 description 1
- POPVCFUFKUDTDP-UHFFFAOYSA-N Cc1c(O)c(cc(c1[N+]([O-])=O)[N+]([O-])=O)[N+]([O-])=O Chemical compound Cc1c(O)c(cc(c1[N+]([O-])=O)[N+]([O-])=O)[N+]([O-])=O POPVCFUFKUDTDP-UHFFFAOYSA-N 0.000 description 1
- IOVCWXUNBOPUCH-UHFFFAOYSA-N Nitrous acid Chemical compound ON=O IOVCWXUNBOPUCH-UHFFFAOYSA-N 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- 230000000844 anti-bacterial effect Effects 0.000 description 1
- 239000003849 aromatic solvent Substances 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-N carbonic acid Chemical class OC(O)=O BVKZGUZCCUSVTD-UHFFFAOYSA-N 0.000 description 1
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 1
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 238000007872 degassing Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000035622 drinking Effects 0.000 description 1
- 239000003651 drinking water Substances 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 239000007792 gaseous phase Substances 0.000 description 1
- 239000003673 groundwater Substances 0.000 description 1
- 229910001385 heavy metal Inorganic materials 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 150000002736 metal compounds Chemical class 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 150000002823 nitrates Chemical class 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- VLZLOWPYUQHHCG-UHFFFAOYSA-N nitromethylbenzene Chemical class [O-][N+](=O)CC1=CC=CC=C1 VLZLOWPYUQHHCG-UHFFFAOYSA-N 0.000 description 1
- 239000001272 nitrous oxide Substances 0.000 description 1
- 235000013842 nitrous oxide Nutrition 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 238000006385 ozonation reaction Methods 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000001376 precipitating effect Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- 239000002352 surface water Substances 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- 229910052715 tantalum Inorganic materials 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C201/00—Preparation of esters of nitric or nitrous acid or of compounds containing nitro or nitroso groups bound to a carbon skeleton
- C07C201/06—Preparation of nitro compounds
- C07C201/16—Separation; Purification; Stabilisation; Use of additives
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D11/00—Solvent extraction
- B01D11/04—Solvent extraction of solutions which are liquid
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/26—Treatment of water, waste water, or sewage by extraction
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C205/00—Compounds containing nitro groups bound to a carbon skeleton
- C07C205/06—Compounds containing nitro groups bound to a carbon skeleton having nitro groups bound to carbon atoms of six-membered aromatic rings
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/34—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32
- C02F2103/36—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32 from the manufacture of organic compounds
Definitions
- the present invention relates to a process for working up alkaline process waste water from the nitration of aromatic compounds or from a mixture W of alkaline process wastewater from the nitration and the aqueous distillate from the sulfuric acid concentration, wherein the alkaline process wastewater or the mixture by adding concentrated sulfuric acid acidified from the work-up of the aqueous, sulfuric acid-containing phase obtained in the nitration, and the acidified process wastewater or wastewater mixture is extracted with an aromatic extractant.
- Aromatic nitro compounds such as mono- and dinitrotoluene are usually prepared by nitrating the corresponding aromatic compounds by means of a mixture of concentrated nitric acid and concentrated sulfuric acid, called nitrating acid. This produces an organic phase containing the crude product of the nitration, and an aqueous phase containing substantially sulfuric acid, water of reaction and water introduced by the nitrating acid. The nitric acid is almost completely consumed in the nitration.
- the aqueous, sulfuric acid-containing phase is mixed again with fresh nitric acid, depending on the technology of the nitration process, or after concentration, and used for nitriding.
- the sulfuric acid must be continuously or discontinuously discharged from the overall process, in order to avoid a concentration of impurities, in particular metallic salts (see also DE 10 143 800 C1).
- the impurities are, for example, impurities originally contained in the nitric acid and metal compounds which are dissolved out of the reactor and tube materials under the highly corrosive conditions prevailing during the reaction and the work-up of the aqueous phase.
- Concentrating the aqueous sulfuric acid-containing phase obtained in the nitration, an aqueous distillate having a low sulfuric acid content, hereinafter referred to as an aqueous distillate of sulfuric acid concentration, and a high sulfuric acid-containing phase are hereinafter concentrated Sulfuric acid, obtained.
- the part of the concentrated sulfuric acid discharged from the nitriding process is also referred to below as waste sulfuric acid.
- the crude product of the nitration of aromatic compounds such as benzene, toluene, xylene, chlorobenzene, etc.
- nitrobenzene NB
- dinitrobenzene DNT
- MNT and DNT mono- and dinitrotoluene
- NCB nitrochlorobenzene
- nitroxylol also small amounts of mono-, di- and Trinitrophenole (hereinafter called nitrophenols), mono-, di- and Trinitrokresole (hereinafter called nitrocresols) and mono-, di- and Trinitroxylenole (hereinafter called nitroxylenols) and others Hydroxyl groups and nitro groups containing compounds and mono- and Dinitrobenzoe Textren (hereinafter called nitrobenzoic acids).
- nitrobenzene NB
- DNT mono- and dinitrotoluene
- NCB nitrochlorobenzene
- nitroxylol also small amounts of mono-, di- and Trinitrophenole (hereinafter called nitrophenols), mono-, di- and Trinitrokresole (hereinafter called nitrocresol
- Aromatic nitro compounds which contain no hydroxyl group or carboxyl group in the molecule are also referred to in the context of the invention as neutral nitrocarbons or neutral nitroaromatics.
- Nitrophenols, nitro cresols, nitroxylenols and nitrobenzoic acids are also summarized below as hydroxynitroaromatics.
- the crude product from the nitration must be freed from the unwanted by-products before further use.
- the by-products are separated by separation of the nitrating acid by multi-stage washing with acidic, alkaline and neutral washing liquid, which is usually washed in the order listed.
- the alkaline wash is usually carried out with aqueous sodium hydroxide solution, aqueous sodium carbonate solution or aqueous ammonia solution.
- the resulting alkaline process wastewater contains nitrophenols, nitro cresols, nitroxylenols and nitrobenzoic acids in the form of their water-soluble salts of the base used. They are usually present in a concentration of 0.2 to 2.5 wt .-%, based on the alkaline process wastewater.
- the alkaline process waste water also contains neutral nitro compounds formed during the nitration, in particular reaction products.
- Neutral nitrocarbons are contained in the alkaline process effluent, usually in an amount of several 1000 ppm.
- the alkaline process wastewater usually contains 500 to 5000 ppm nitrates, 500 to 5000 ppm nitrite and a few hundred ppm of sulfate. These ions are derived from nitration.
- the ingredients result in a chemical oxygen demand of 1000 to 20000 mg / L.
- the nitrophenols, nitro cresols, nitroxylenols, nitriobenzoic acids and especially their salts are intensely colored and highly toxic to the environment.
- the nitrophenols and especially their salts are explosives in higher concentrations or in bulk and must be removed from the wastewater before disposal and disposed of in such a way that they pose no danger to the environment.
- the alkaline process wastewater also contains neutral nitro bodies formed in the nitration, in particular reaction products. Since the aromatic nitro compounds have overall bactericidal properties and thus make a biological purification of the waste water impossible, a purification or processing of the wastewater containing aromatic nitro compounds is necessary.
- the hydroxynitroaromatics contained in the alkaline process wastewater can also be converted by acidification into a separating organic phase, which is subsequently separated off.
- the equipment used for the separation and separation must be heated. Nevertheless, there is the problem of so-called "fouling.” This means that the pumps and piping systems used to separate the seeping organic phase clog very quickly by precipitating and crystallizing impurities and therefore there is a high need for cleaning.
- This object is achieved by the following process for working up alkaline process wastewater from the nitration of aromatic compounds to mono-, di- and trinitroaromatics having a pH of 7.5 to 13 or a mixture W having a pH of 6-10 from alkaline process effluent and aqueous distillate of sulfuric acid concentration comprising the steps a) acidification of the alkaline process effluent or of the mixture W by addition of concentrated sulfuric acid, which originates from the workup of the obtained during the nitration aqueous, sulfuric acid-containing phase, to a pH below 2, wherein a mixture of A separating more organic Phase and acidic aqueous phase is formed, and
- the alkaline process waste water treated with the process according to the invention is greatly depleted of poorly degradable neutral nitro bodies, nitro cresols and nitrobenzoic acids as well as of nitrite.
- a further advantage of the process according to the invention is that for the acidification of the alkaline process wastewater, the sulfuric acid resulting from the concentration can be used from the preparation process of the nitroaromatics, in particular because part of the concentrated sulfuric acid is known as waste sulfuric acid from the cycle of Nitration and sulfuric acid processing must anyway be discharged and disposed of.
- the concentrated sulfuric acid containing by corrosion (pipelines) in the nitration salts comprising Fe, Cr, Ni, Ta, and traces of other heavy metals in the form of their sulfates.
- the salt concentration exceeds 300 ppm, part of the acid is discharged from the process as so-called waste sulfuric acid and must be disposed of or purified by other methods.
- this waste sulfuric acid is particularly advantageous because it is the Entsorgungspp. Save on processing costs.
- the amount of concentrated sulfuric acid to be removed can be used completely in the process according to the invention without the need for further addition of additional sulfuric acid. This leads to a very economical use of different material flows.
- the use of the concentrated sulfuric acid also leads to the fact that the acidification of the alkaline process wastewater, a large part of the nitrite dissolved in the alkaline process waste water is protonated to nitrous acid, which then decomposes into nitric acid and nitrogen oxides, the nitrogen oxides can be separated.
- the Nitriding acid is fed into the nitric acid recovery of the nitriding plant and thus the process is not lost.
- the chemical oxygen demand of the wastewater stream treated by the process according to the invention is significantly reduced.
- the use of concentrated waste sulfuric acid does not unnecessarily increase the amount of process wastewater to be purified, as is the case with the use of dilute acid.
- the process according to the invention is used for working up alkaline process wastewater from the nitration of aromatic compounds or from a mixture W of alkaline process wastewater from the nitration and the aqueous distillate from the sulfuric acid concentration.
- the process is used in the nitration of benzene, toluene, xylene, chlorobenzene and / or dichlorobenzene.
- the alkaline process wastewater obtained from the single-stage or multi-stage washing of the crude product of the nitration with aqueous, alkaline solution such as sodium hydroxide, aqueous carbonate or bicarbonate solution or aqueous ammonia solution has a pH of 7.5 to, depending on the base used 13, preferably 8 to 10, measured at 60 ° C on.
- the aqueous distillate used in the use of the mixture from the concentration of sulfuric acid has a pH of 0.5 to 1, 5, measured at 60 ° C and also contains proportions of mono- and dinitrotoluene in amounts of about 100 - 250 mg / L.
- the mixture of alkaline process water and aqueous distillate from the sulfuric acid concentration has a pH of 6 to 10 at mixing ratios of 2: 1 to 3: 2.
- the pH values in each case refer to the measurement at 60 ° C.
- the acidified, originally alkaline process waste water or the acidified mixture W of alkaline process wastewater and aqueous distillate of sulfur concentration together with the separating organic phase in the context of the invention is referred to as mixture A.
- the concentrated sulfuric acid used for the acidification has a concentration of 85 to 95 wt .-%, preferably from 90 to 93 wt .-% to.
- waste sulfuric acid obtained only in the nitration is added for acidification in step a), particularly preferably the entire waste sulfuric acid obtained in the nitration is added in step a).
- the control of the addition of the concentrated sulfuric acid is advantageously carried out via an online pH measurement.
- the mixing of the concentrated sulfuric acid with the alkaline process wastewater or with the mixture leads to a strong evolution of gas.
- the separating gas mixture contains nitrogen oxides, in particular nitrogen monoxide and nitrogen dioxide.
- the separating gas usually contains from 70 to 98.9% by volume of carbon dioxide and from 1.1 to 30% by volume of nitrous gases (nitrogen monoxide, nitrogen dioxide, dinitrogen monoxide) in the preceding DNT washing with aqueous alkali carbonate or alkali hydrogencarbonate solution.
- the separating gas mixture contains 80 to 98 vol .-% carbon dioxide, 2 to 20 vol .-% nitrous gases.
- the gaseous phase consists essentially of nitrous gases (NOx), usually 47 to 98% nitrogen monoxide, 1 to 47% nitrogen dioxide and 1 to 6% nitrous oxide.
- NOx nitrous gases
- the nitrogen oxides which precipitate on acidification are preferably separated off and used for the production of nitric acid.
- the separated nitrogen oxides are particularly preferably recycled to the nitric acid recovery of the nitriding plant.
- the gas mixture is usually fed into the absorption columns of the NOx absorption of the nitric acid recovery of the nitration plants. It is particularly advantageous if the entire gas mixture is recycled directly and without prior separation of CO2 and purification.
- an aromatic extractant is used in the extraction of the mixture A obtained in step a) in step b) of the process according to the invention. All aromatic compounds customarily used for extractions, in particular aromatic solvents, are suitable.
- the starting aromatic compound used in the nitration is used as the extraction solution. That is, in the nitration of benzene to NB or DNB is benzene, in the nitration of toluene to MNT or DNT toluene is used.
- the nitro group containing a nitro group less such as in the case of DNT MNT, can be used.
- the alkaline process wastewater usually accumulates at a temperature of 50 to 80 ° C.
- the alkaline process waste water is acidified at this temperature by adding the waste sulfuric acid (step a)).
- the extraction is preferably carried out in a temperature range of 40-80 ° C, but more preferably at the temperature at which the scrubbing of the crude nitroaromatic mixture is carried out with the alkaline scrubbing water.
- the extraction temperature is 60 to 70 ° C.
- the ratio extraction agent / mixture A should be selected so that extraction of the neutral nitro bodies and the hydroxynitroaromatics can be achieved up to the desired limit value or the required minimum value with the lowest possible number of extraction stages.
- the weight ratio of extractant used to mixture A can be varied in the range from 1:10 to 1: 2, preferably from 1: 5 to 1: 3.
- the mixture A is extracted one to five times, preferably one to three times.
- mixture A should be extracted at least twice (2 steps).
- wastewater without mono- and dinitrotoluene and without trinitro cresols - at least a three-stage extraction should be used.
- the extraction is carried out according to the methods known to those skilled in the liquid / liquid extraction process.
- the extraction is in countercurrent carried out.
- mixer / settler apparatuses or stirred multistage or pulsed packed and sieve tray columns can be used as extraction apparatuses.
- static mixers in conjunction with suitable separation apparatus or columns without energy input can be used to carry out the extraction.
- mechanical energy is preferably introduced into the system during the extraction, for example by stirring or pulsing.
- the extraction is carried out in a pulsating packed column, a stirred cell extractor or a mixer-settler apparatus.
- the extracted after neutralization extracted with extracted neutral nitroaromatics and Hydroxynitroaromaten extraction agent can be recycled within each countercurrent stage and only the corresponding provided ratio of extractant / mixture A freshly added amount of extractant is discharged and returned to the nitration. That is, a certain amount of fresh extractant is added to adjust an intended ratio of extractant / mixture, and an amount of extractant corresponding to this amount is discharged and recycled to the nitration.
- the extractant after extraction including the extracted neutral nitroaromatics and hydroxynitro compounds, is recycled to the nitriding unit.
- the aqueous phase usually contains about 100-500 ppm extractant after extraction.
- the residues of the aromatic extractant dissolved in the aqueous phase can be removed by stripping or distillation from the aqueous phase, for example by means of steam or nitrogen stripping.
- the energy requirement for stripping the volatile extractants is substantially lower than that for stripping the nitro compounds made therefrom.
- the resulting in the stripping, still extractant-containing water together with the in the Strippung separated extractant is added to the alkaline wash water before extraction again.
- the process according to the invention can be carried out batchwise or continuously. According to the invention, the process is carried out continuously.
- TOC organically bound total carbon, measured according to DIN EN 1484 (1997) / AQS P-14 (1995):
- the total carbon TC and total organic carbon TOC can be determined.
- the inorganic carbon TIC can be determined by subtracting the TOC from the TC.
- the inorganic carbon (carbonates, hydrogen carbonates, etc.) is expelled by addition of hydrochloric acid, followed by metering the sample into the quartz reactor, where the catalytic oxidation of the organically bound carbon at 850 ° C occurs C. The resulting carbon dioxide is detected in the IR detector.
- the alkaline process effluent originates from the scrubbing of the organic phase from the nitration with aqueous sodium carbonate solution.
- Toluene extraction in a pulsating packed column with an extraction ratio of toluene to wastewater 1: 3.
- the extraction was carried out with alkaline process waste water from the nitration of toluene without acidification, with acidification to 4 ⁇ pH ⁇ 4.8 and with acidification to pH ⁇ 2 (cf. according to the invention).
- the extraction column was an online pH measurement and the exhaust gas of the forming mixture of CO2 and NOx was fed via a line to a compressor and finally to an absorber column.
- the optionally acidic mixture passed continuously at a throughput of 220 l / h from the top into the pulsed packed column (pPK). From below, the toluene was transported upwards in countercurrent at a rate of 73 l / h. The light solvent toluene took up the organic components and the resulting toluene extract was now separated above a Seperator and returned to the nitration.
- the used pPK with a diameter of DN 80 and a length of 2400 mm consisted of 4 extraction stages.
- the column load was 61, 32 m 3 / m 2 h at a rate of 293 l / h.
- Wastewater Wastewater water (acid, water (acid, er)
- Example 2 Toluene extraction in a stirred cell extractor
- Extraction ratio of toluene to waste water 1: 3.
- the extraction was carried out with alkaline wastewater from the nitration without acidification, with acidification to 4 ⁇ pH ⁇ 4.8 and with acidification to pH ⁇ 2 (according to the invention).
- the toluene was carried up in countercurrent at a rate of 401 / h.
- the light solvent toluene took up the organic components and the resulting toluene extract was now separated above a Seperator and returned to the nitration.
- the RZE used with a diameter of DN 100 and a length of 1000 mm consisted of 15 extraction stages.
- the load of the RZE was 20.37 m 3 / m 2 h at a throughput of 160 l / h.
- Example 3 Toluene extraction in a pulsed packed column
- Extraction ratio of toluene to waste water 1: 3.
- the extraction was carried out with alkaline process waste water from the nitration without acidification, with acidification to 4 ⁇ pH ⁇ 4.8 and with acidification to pH ⁇ 2 (according to the invention).
- a mixture of alkaline DNT wastewater and SAC waste water (aqueous distillate of sulfuric acid concentration) in a mixing ratio of 3: 2 with a pH of 7.2 was prepared in a 50 liter stirred tank and optionally with 93% waste sulfuric acid, which was added separately via a pump in the stirred tank, acidified.
- a pump in the stirred tank acidified.
- the exhaust gas of the forming mixture of CO2 and NOx was fed via a line to a compressor and finally to an absorber column, as i.a. the gas evolution during extraction adversely affected the plant safety and the throughput of the pPK.
- the acidic waste water passed continuously from above into the pPK at a rate of 270 l / h. From below, the toluene was carried up in countercurrent at a rate of 90 l / h. The light solvent toluene took the organic parts and the resulting toluene extract was now separated above a Seperator and returned to the nitration.
- the used pPK with a diameter of DN 80 and a length of 2400 mm consisted of 4 extraction stages.
- the column load here was 75.34 m 3 / m 2 h at a throughput of 360 l / h.
- Example 4 Alkaline DNT wastewater + SAC wastewater
- Toluene extraction in a stirred cell extractor with an extraction ratio of toluene to wastewater 1: 3.
- the extraction was carried out with alkaline process waste water from the nitration without acidification, with acidification to 4 ⁇ pH ⁇ 4.8 and with acidification to pH ⁇ 2 (according to the invention) ,
- the acidic wastewater was continuously fed from above into the RZE at a rate of 1201 / h. From below, the toluene was carried up in countercurrent at a rate of 401 / h. The light solvent toluene took up the organic components and the resulting toluene extract was now separated above a Seperator and returned to the nitration.
- the RZE used with a diameter of DN 100 and a length of 1000 mm consisted of 15 extraction stages.
- the load of the RZE was 20.37 m 3 / m 2 h at a throughput of 160 l / h.
- the analysis results are shown in Table 4.
- Example 7 Alkaline DNT wastewater
- TOC 4 in mg / L 1516 1 132 954 By omitting the pulsator little mechanical energy is entered and extracted less nitrotoluenes and nitro cresols, as can be seen in comparison with Examples 5 and 6 (each for the ratio of toluene to wastewater of 1: 4).
- Example 8 Alkaline DNT wastewater Toluene extraction in a mixer-settler apparatus 2 kg of alkaline DNT wastewater were acidified to a pH of 0.5 with 1 g of 93% waste sulfuric acid and 1 kg of toluene in a mixer-settler apparatus extracted in the ratio 1: 2 (toluene: wastewater).
- the exhaust gas produced by acidification (NOx + CO2) after the stirring process of an exhaust gas treatment for the production of nitric acid was supplied.
- a wastewater mixture with a pH of 4.8 leads only to the extraction of MNT and DNT.
- the nitro cresols and nitrobenzoic acids are not extracted, i. the total amount of nitro cresols and nitrobenzoic acids is supplied with the waste water to the ozonation / thermolysis / biological workup.
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Abstract
L'invention concerne un procédé de retraitement d'eaux usées alcalines de procédés issues de la nitruration de composés aromatiques en monoaromates, diaromates et trinitroaromates d'un pH de 7,5 à 13 ou d'un mélange W d'un pH de 6 à 10 issu d'eaux usées alcalines de procédés, et du distillat aqueux du concentré d'acide sulfurique, comprenant les étapes consistant à a) acidifier les eaux usées alcalines de procédés ou le mélange W à un pH en deçà de 2 par apport d'acide sulfurique concentré issu du retraitement de la phase aqueuse contenant de l'acide sulfurique précipité lors de la nitruration, ce qui permet d'obtenir un mélange A de la phase organique en précipitation et de la phase aqueuse acide, et b) à extraire le mélange A par un agent d'extraction aromatique.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP10793218A EP2513035A1 (fr) | 2009-12-16 | 2010-12-13 | Extraction de toluène acide d'eaux usées dinitrotoluène |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP09179501 | 2009-12-16 | ||
| PCT/EP2010/069548 WO2011082978A1 (fr) | 2009-12-16 | 2010-12-13 | Extraction de toluène acide d'eaux usées dinitrotoluène |
| EP10793218A EP2513035A1 (fr) | 2009-12-16 | 2010-12-13 | Extraction de toluène acide d'eaux usées dinitrotoluène |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP2513035A1 true EP2513035A1 (fr) | 2012-10-24 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP10793218A Withdrawn EP2513035A1 (fr) | 2009-12-16 | 2010-12-13 | Extraction de toluène acide d'eaux usées dinitrotoluène |
Country Status (7)
| Country | Link |
|---|---|
| US (1) | US20120248038A1 (fr) |
| EP (1) | EP2513035A1 (fr) |
| JP (1) | JP2013514300A (fr) |
| KR (1) | KR20120102120A (fr) |
| CN (1) | CN102656137A (fr) |
| BR (1) | BR112012013549A2 (fr) |
| WO (1) | WO2011082978A1 (fr) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110170185A (zh) * | 2019-05-30 | 2019-08-27 | 湖北东方化工有限公司 | 一种废硫酸硝基化合物分离的装置及方法 |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| PL2295375T3 (pl) * | 2009-09-15 | 2016-10-31 | Sposób i urządzenie do obróbki odpadowych kwasów siarkowych z procesu nitrowania | |
| EP2513034B1 (fr) | 2009-12-16 | 2014-07-30 | Basf Se | Adsorption des boues acides d'eaux usées dinitrotoluène |
| CN103754972A (zh) * | 2014-01-08 | 2014-04-30 | 南京理工大学 | 含氟溶剂在废酸处理中的应用 |
| DE102015106617B4 (de) * | 2014-07-07 | 2017-09-21 | Josef Meissner Gmbh & Co. Kg | Verfahren zur Aufreinigung von Rohdinitrotoluolen |
| CN107459196B (zh) * | 2017-08-30 | 2022-03-29 | 湖北绿色家园材料技术股份有限公司 | 一种固化剂生产废水处理装置及其综合处理方法 |
| TWI642628B (zh) * | 2017-12-08 | 2018-12-01 | 中國鋼鐵股份有限公司 | 水中苯、甲苯及二甲苯減量及回收之方法及裝置 |
| DE102018217955B4 (de) * | 2018-10-19 | 2020-06-04 | Plinke Gmbh | Verfahren zur Aufarbeitung von Mischsäure und Abwasser aus der Nitrierung von Aromaten sowie Vorrichtung zur Durchführung des Verfahrens |
| CN109627170B (zh) * | 2018-12-17 | 2021-09-14 | 湖北东方化工有限公司 | 从硝基甲苯酸性废水提取多硝基甲苯的方法 |
| CN109320422B (zh) * | 2018-12-17 | 2023-12-05 | 湖北东方化工有限公司 | 一种酸性废水提取多硝基甲苯的装置 |
| CN115893339B (zh) * | 2022-12-15 | 2025-04-25 | 万华化学集团股份有限公司 | 一种粗dnt中硝酸的回收方法 |
| CN117509875B (zh) * | 2023-12-11 | 2024-07-30 | 西安德兴环保科技有限公司 | 一种高硫废碱液和po/sm装置废碱液协同处理的方法 |
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|---|---|---|---|---|
| US4562052A (en) * | 1984-07-09 | 1985-12-31 | Air Products And Chemicals, Inc. | Process for the removal of nitrogen oxides from nitric acid plant tail gas |
| US4925565A (en) * | 1988-09-12 | 1990-05-15 | First Chemical Corporation | Process for extracting and disposing of nitrophenolic by-products |
| US4986917A (en) * | 1989-07-10 | 1991-01-22 | First Chemical Corporation | Selective recovery of a nitrophenolic by-product from nitration waste water by extraction |
| FR2767318B1 (fr) * | 1997-08-13 | 1999-10-29 | Rhodia Chimie Sa | Procede de recuperation d'acide nitrique compris dans un melange de composes aromatiques dinitres |
| DE10143800C1 (de) | 2001-09-06 | 2002-08-22 | Plinke Gmbh | Verfahren zur Minimierung des Abwassers bei der Herstellung von DNT |
| US6506948B1 (en) | 2002-02-07 | 2003-01-14 | Air Products And Chemicals, Inc. | Toluene extraction of dinitrotoluene wash water |
| DE10329304A1 (de) * | 2003-06-30 | 2005-02-03 | Bayer Materialscience Ag | Verfahren zur Aufarbeitung des bei der Herstellung von Dinitrotoluol anfallenden Abwassers |
| DE10329303A1 (de) * | 2003-06-30 | 2005-02-03 | Bayer Materialscience Ag | Verfahren zur Aufarbeitung des bei der Herstellung von Dinitrotoluol anfallenden Abwassers |
| DE10345601A1 (de) * | 2003-09-29 | 2005-05-12 | Basf Ag | Verfahren zur Entfernung von Nitrokresolen aus Abwasser der Mononitrotoluolherstellung und zur weiteren Verwendung des Extraktes |
| DE102005050106B4 (de) * | 2005-10-18 | 2008-04-30 | Josef Meissner Gmbh & Co. Kg | Rückgewinnung von Nitriersäuregemischen aus Nitrienprozessen |
| CN100369885C (zh) * | 2006-01-17 | 2008-02-20 | 甘肃银光化学工业集团有限公司 | 连续制备二硝基甲苯的方法及其装置 |
| CN101502746B (zh) * | 2009-04-09 | 2011-01-12 | 江苏扬农化工集团有限公司 | 芳香类硝基化合物氯化尾气中氮氧化物的处理方法 |
-
2010
- 2010-12-13 US US13/516,280 patent/US20120248038A1/en not_active Abandoned
- 2010-12-13 EP EP10793218A patent/EP2513035A1/fr not_active Withdrawn
- 2010-12-13 KR KR1020127018450A patent/KR20120102120A/ko not_active Withdrawn
- 2010-12-13 JP JP2012543666A patent/JP2013514300A/ja active Pending
- 2010-12-13 BR BR112012013549A patent/BR112012013549A2/pt not_active IP Right Cessation
- 2010-12-13 WO PCT/EP2010/069548 patent/WO2011082978A1/fr not_active Ceased
- 2010-12-13 CN CN2010800564767A patent/CN102656137A/zh active Pending
Non-Patent Citations (1)
| Title |
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| See references of WO2011082978A1 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110170185A (zh) * | 2019-05-30 | 2019-08-27 | 湖北东方化工有限公司 | 一种废硫酸硝基化合物分离的装置及方法 |
| CN110170185B (zh) * | 2019-05-30 | 2023-07-25 | 湖北东方化工有限公司 | 一种废硫酸硝基化合物分离的装置及方法 |
Also Published As
| Publication number | Publication date |
|---|---|
| BR112012013549A2 (pt) | 2017-10-10 |
| CN102656137A (zh) | 2012-09-05 |
| KR20120102120A (ko) | 2012-09-17 |
| WO2011082978A1 (fr) | 2011-07-14 |
| JP2013514300A (ja) | 2013-04-25 |
| US20120248038A1 (en) | 2012-10-04 |
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