EP0000935A1 - Verfahren zur Reinigung von Schwefelsäure - Google Patents
Verfahren zur Reinigung von Schwefelsäure Download PDFInfo
- Publication number
- EP0000935A1 EP0000935A1 EP78100704A EP78100704A EP0000935A1 EP 0000935 A1 EP0000935 A1 EP 0000935A1 EP 78100704 A EP78100704 A EP 78100704A EP 78100704 A EP78100704 A EP 78100704A EP 0000935 A1 EP0000935 A1 EP 0000935A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- acid
- sulfuric acid
- ammonium
- weight
- waste
- 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- Withdrawn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
- QAOWNCQODCNURD-UHFFFAOYSA-N sulfuric acid group Chemical class S(O)(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 title claims abstract description 68
- 238000000034 method Methods 0.000 title claims abstract description 20
- 238000000746 purification Methods 0.000 title claims description 4
- OLBVUFHMDRJKTK-UHFFFAOYSA-N [N].[O] Chemical class [N].[O] OLBVUFHMDRJKTK-UHFFFAOYSA-N 0.000 claims abstract description 20
- BFNBIHQBYMNNAN-UHFFFAOYSA-N ammonium sulfate Chemical compound N.N.OS(O)(=O)=O BFNBIHQBYMNNAN-UHFFFAOYSA-N 0.000 claims abstract description 20
- 229910052921 ammonium sulfate Inorganic materials 0.000 claims abstract description 18
- 235000011130 ammonium sulphate Nutrition 0.000 claims abstract description 18
- 239000012535 impurity Substances 0.000 claims abstract description 5
- 238000006243 chemical reaction Methods 0.000 claims description 28
- 238000010438 heat treatment Methods 0.000 claims description 22
- 239000007789 gas Substances 0.000 claims description 15
- 238000004519 manufacturing process Methods 0.000 claims description 10
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 9
- VEZUQRBDRNJBJY-UHFFFAOYSA-N cyclohexanone oxime Chemical compound ON=C1CCCCC1 VEZUQRBDRNJBJY-UHFFFAOYSA-N 0.000 claims description 6
- JBKVHLHDHHXQEQ-UHFFFAOYSA-N epsilon-caprolactam Chemical compound O=C1CCCCCN1 JBKVHLHDHHXQEQ-UHFFFAOYSA-N 0.000 claims description 6
- 239000000203 mixture Substances 0.000 claims description 6
- WWILHZQYNPQALT-UHFFFAOYSA-N 2-methyl-2-morpholin-4-ylpropanal Chemical compound O=CC(C)(C)N1CCOCC1 WWILHZQYNPQALT-UHFFFAOYSA-N 0.000 claims description 5
- 229910021529 ammonia Inorganic materials 0.000 claims description 4
- BIGPRXCJEDHCLP-UHFFFAOYSA-N ammonium bisulfate Chemical compound [NH4+].OS([O-])(=O)=O BIGPRXCJEDHCLP-UHFFFAOYSA-N 0.000 claims description 4
- 238000002386 leaching Methods 0.000 claims description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 4
- 229910019142 PO4 Inorganic materials 0.000 claims description 3
- 230000029087 digestion Effects 0.000 claims description 2
- 229910052500 inorganic mineral Inorganic materials 0.000 claims description 2
- 239000011707 mineral Substances 0.000 claims description 2
- 238000005859 coupling reaction Methods 0.000 claims 1
- 238000001704 evaporation Methods 0.000 claims 1
- 230000008020 evaporation Effects 0.000 claims 1
- 150000003951 lactams Chemical class 0.000 claims 1
- 150000002923 oximes Chemical class 0.000 claims 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 claims 1
- 239000010452 phosphate Substances 0.000 claims 1
- 239000002253 acid Substances 0.000 abstract description 36
- 239000002699 waste material Substances 0.000 abstract description 24
- 238000006396 nitration reaction Methods 0.000 abstract description 9
- 150000001491 aromatic compounds Chemical class 0.000 abstract description 4
- 150000007513 acids Chemical class 0.000 abstract description 2
- 239000001117 sulphuric acid Substances 0.000 abstract 2
- 235000011149 sulphuric acid Nutrition 0.000 abstract 2
- 239000001166 ammonium sulphate Substances 0.000 abstract 1
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 15
- 210000004072 lung Anatomy 0.000 description 14
- -1 ammonium ions Chemical class 0.000 description 13
- 150000001875 compounds Chemical class 0.000 description 8
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 6
- 239000000243 solution Substances 0.000 description 6
- 238000004458 analytical method Methods 0.000 description 5
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 4
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 4
- 229910017604 nitric acid Inorganic materials 0.000 description 4
- IOVCWXUNBOPUCH-UHFFFAOYSA-N Nitrous acid Chemical compound ON=O IOVCWXUNBOPUCH-UHFFFAOYSA-N 0.000 description 3
- 230000000802 nitrating effect Effects 0.000 description 3
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 3
- RXQNKKRGJJRMKD-UHFFFAOYSA-N 5-bromo-2-methylaniline Chemical compound CC1=CC=C(Br)C=C1N RXQNKKRGJJRMKD-UHFFFAOYSA-N 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 description 2
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- JHIVVAPYMSGYDF-UHFFFAOYSA-N cyclohexanone Chemical compound O=C1CCCCC1 JHIVVAPYMSGYDF-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000003337 fertilizer Substances 0.000 description 2
- 238000004868 gas analysis Methods 0.000 description 2
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 2
- 229910052753 mercury Inorganic materials 0.000 description 2
- 230000003472 neutralizing effect Effects 0.000 description 2
- LQNUZADURLCDLV-UHFFFAOYSA-N nitrobenzene Chemical compound [O-][N+](=O)C1=CC=CC=C1 LQNUZADURLCDLV-UHFFFAOYSA-N 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 238000006053 organic reaction Methods 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 235000021317 phosphate Nutrition 0.000 description 2
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 239000008096 xylene Substances 0.000 description 2
- ZNBNBTIDJSKEAM-UHFFFAOYSA-N 4-[7-hydroxy-2-[5-[5-[6-hydroxy-6-(hydroxymethyl)-3,5-dimethyloxan-2-yl]-3-methyloxolan-2-yl]-5-methyloxolan-2-yl]-2,8-dimethyl-1,10-dioxaspiro[4.5]decan-9-yl]-2-methyl-3-propanoyloxypentanoic acid Chemical compound C1C(O)C(C)C(C(C)C(OC(=O)CC)C(C)C(O)=O)OC11OC(C)(C2OC(C)(CC2)C2C(CC(O2)C2C(CC(C)C(O)(CO)O2)C)C)CC1 ZNBNBTIDJSKEAM-UHFFFAOYSA-N 0.000 description 1
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- AVXURJPOCDRRFD-UHFFFAOYSA-N Hydroxylamine Chemical compound ON AVXURJPOCDRRFD-UHFFFAOYSA-N 0.000 description 1
- 235000011114 ammonium hydroxide Nutrition 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 229910000378 hydroxylammonium sulfate Inorganic materials 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 239000000543 intermediate Substances 0.000 description 1
- DOTMOQHOJINYBL-UHFFFAOYSA-N molecular nitrogen;molecular oxygen Chemical compound N#N.O=O DOTMOQHOJINYBL-UHFFFAOYSA-N 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 230000008707 rearrangement Effects 0.000 description 1
- 238000005185 salting out Methods 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B17/00—Sulfur; Compounds thereof
- C01B17/69—Sulfur trioxide; Sulfuric acid
- C01B17/90—Separation; Purification
- C01B17/94—Recovery from nitration acids
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B17/00—Sulfur; Compounds thereof
- C01B17/69—Sulfur trioxide; Sulfuric acid
- C01B17/90—Separation; Purification
Definitions
- the invention relates to a process for the purification of aqueous sulfuric acid obtained as waste acid in the nitration of aromatic compounds by reaction with ammonium ions of nitrogen-oxygen compounds contained therein as an impurity.
- the content of this so-called waste acid is between about 20 and 96, in particular about 60 to 80 wt .-% H 2 S0 4 , depending on the concentration of sulfuric acid in the nitrating acid used and the amount of water of reaction during nitration per unit weight of nitrating acid, that is absorbed by the sulfuric acid.
- the nitrogen-oxygen compounds contained therein are predominantly compounds of the empirical formula NO x , where x stands for the numbers 1, 1.5 or 2, ie the compounds NO, N 2 O 3 , N0 2 or N204 and acids corresponding to these compounds , nitrous acid (HNO 2 ) and nitrosylsulfuric acid (HSO 4 NO).
- the main component is N0 2 , also in the form of nitrous acid and nitrosylsulfuric acid, which is already contained as N 2 0 4 in the highly concentrated nitric acid used for the nitration and is only partially implemented in the nitration in side reactions.
- NO compounds already convert to NO 2 under the influence of atmospheric oxygen according to 2 NO + O 2 NO 2 + 27.1 Kcal.
- Such waste acid can be used in various ways.
- Raw phosphates can be broken down for the manufacture of fertilizers. This reaction and the mostly associated extraction of phosphoric acid usually takes place in the heat. This removes nitrogen oxides that escape with the exhaust air.
- the waste acid can also be used to digest other minerals or ores, e.g. of copper ores.
- a process has now been found for the purification of aqueous sulfuric acid which contains nitrogen-oxygen compounds as impurities, which is characterized in that the sulfuric acid is prepared in the presence of ammonium sulfate or ammonium bisulfate which has been prepared from waste gases containing ammonia or from leaching liquor. treated at temperatures of 30-300 ° C.
- the reaction temperature in the reaction according to the invention is approximately in the range from 30 to 300.degree. C., preferably at temperatures between 70 and 200.degree. C., in particular between 100 and 150.degree.
- the starting sulfuric acid is an aqueous sulfuric acid which is recovered as so-called waste acid in the nitration of aromatic compounds, in particular benzene, toluene or xylene with a mixture of oleum and / or sulfuric acid and highly concentrated nitric acid has an H 2 S0 4 content of approximately 20 to 96% by weight, preferably 20 to 89% by weight, particularly preferably approximately 60 to 80% by weight.
- ammonium sulfate or ammonium hydrogen sulfate which is in the form of an aqueous solution with about 10 to about 60% by weight, in particular about 38 to 42% by weight, as waste liquor in many organic reactions using concentrated sulfuric acid or oleum by neutralizing the during or after the reaction of the inevitably obtained aqueous sulfuric acid is obtained by neutralization with ammonia
- saturated ammonium sulfate or ammonium hydrogen sulfate solution is obtained at the corresponding temperature, and thereby exploits its salting-out effect with respect to the organic reaction products.
- leaching is e.g. obtained in the production of cyclohexanone oxime from cyclohexanone and hydroxylamine sulfate and in the production of caprolactam by rearrangement of cyclohexanone oxime in oleum.
- ammonium sulfate or ammonium hydrogen sulfate solutions can inevitably be obtained, e.g. also by neutralizing aqueous ammonia solutions with sulfuric acid or by treating ammonia-containing exhaust gases with sulfuric acid.
- the amount of the ammonium ions to be used in the process according to the invention depends on the content of nitrogen-oxygen compounds in the sulfuric acid.
- the reaction of the nitrogen-oxygen compounds with ammonium ions is determined by a series of equilibria and reactions between them and with water and oxygen, in which nitrous acid and nitric acid also occur as intermediates (Hofmann & Hofmann, Anorganische Chemie, 11th edition (1945) , Page 103).
- the stoichiometrically necessary amount in the inventive method according to the simplified reaction equation calculated that is, per mole of nitrogen-oxygen compounds, determined by analysis according to the lung as NO, 1 g equivalent of ammonium ions is understood as the stoichiometrically required amount.
- the determination of the nitrogen-oxygen compounds as NO according to the lung which is necessary to determine the stoichiometrically required amount of ammonium ions, is a known analytical method.
- the aqueous sulfuric acid to be purified is mixed with the amount of ammonium ions chosen in accordance with the content of nitrogen-oxygen compounds
- ammonium bisulfate and / or ammonium sulfate in the form of ammonium bisulfate and / or ammonium sulfate in bulk or in aqueous solution, in particular the above-described forcible solutions (waste solutions) and heats up to the reaction temperature for a certain time.
- reaction time necessary for the complete conversion of the nitrogen-oxygen compounds depends on the selected amount of ammonium ions and the reaction temperature; in general, the greater their excess and the higher the temperature, the shorter the reaction time.
- the implementation according to the invention can be advantageous to be carried out at the reaction temperature only when, for other reasons, the sulfuric acid to be purified has to be heated or is being heated.
- a waste acid mixed with the appropriate amount of ammonium ions e.g. for the production of fertilizers and / or the production of phosphoric acid by digestion of crude phosphates with this waste acid or concentrate according to the so-called Plinke process without heating them separately beforehand.
- the reaction according to the invention at the reaction temperature then takes place either during an exothermic reaction with self-heating or during the heating by supplied heat.
- the sulfuric acid purified by the process according to the invention is subsequently largely colorless and water-clear, while e.g. Waste acid from benzene nitration has a dark red-brown color.
- the content of nitrogen-oxygen compounds (NO x ) is 0.108% by weight or 0.292 mmol calculated as NO.
- the NO x determination according to a) gave 0.04% by weight of NO in the treated acid.
- the analysis according to a) of the heated acid showed 0.00% by weight of NO.
- the NO determination of the treated waste acid after lung was 0.119% by weight NO.
- the content of NO 2 compounds was determined to be 0.132% by weight or 0.354 mmol NO in nash lung in 5 ml of a 90% by weight waste sulfuric acid.
- the NO x determination gave 0.02% by weight of NO after heating the acid to the lungs.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Removal Of Specific Substances (AREA)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE2738993 | 1977-08-30 | ||
| DE2738993 | 1977-08-30 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP0000935A1 true EP0000935A1 (de) | 1979-03-07 |
Family
ID=6017642
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP78100704A Withdrawn EP0000935A1 (de) | 1977-08-30 | 1978-08-18 | Verfahren zur Reinigung von Schwefelsäure |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP0000935A1 (it) |
| JP (1) | JPS5446198A (it) |
| IT (1) | IT7850872A0 (it) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2512993B1 (de) * | 2009-12-16 | 2013-11-27 | Basf Se | VERFAHREN ZUR AUFARBEITUNG VON NOx-HALTIGEN ABGASEN AUS ABWASSERSTRÖMEN VON NITRIERANLAGEN |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2198686A (en) * | 1939-03-20 | 1940-04-30 | Gen Chemical Corp | Manufacture of sulphuric acid |
| FR2265675A1 (en) * | 1974-03-29 | 1975-10-24 | Lilly Co Eli | Purifying spent nitration sulphuric acid - contg. nitrogen oxides, inorganic and organic fluorides, and organic cpds |
-
1978
- 1978-08-18 EP EP78100704A patent/EP0000935A1/de not_active Withdrawn
- 1978-08-28 IT IT7850872A patent/IT7850872A0/it unknown
- 1978-08-28 JP JP10396878A patent/JPS5446198A/ja active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2198686A (en) * | 1939-03-20 | 1940-04-30 | Gen Chemical Corp | Manufacture of sulphuric acid |
| FR2265675A1 (en) * | 1974-03-29 | 1975-10-24 | Lilly Co Eli | Purifying spent nitration sulphuric acid - contg. nitrogen oxides, inorganic and organic fluorides, and organic cpds |
Non-Patent Citations (1)
| Title |
|---|
| CHEMICAL ABSTRACTS, vol. 34, 1940, Seite 4867, "Denitration of 65-67% sulfuric acid" (ZIL'BERMAN) J. Chem. Ind. (USSR) 17, 47-9 (1940) * |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5446198A (en) | 1979-04-11 |
| IT7850872A0 (it) | 1978-08-28 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
| 17P | Request for examination filed | ||
| AK | Designated contracting states |
Designated state(s): BE CH DE FR GB NL |
|
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN |
|
| 18W | Application withdrawn | ||
| RIN1 | Information on inventor provided before grant (corrected) |
Inventor name: LARBIG, WOLFGANG, DR. |