CN112094194A - Method for controlling TOC in waste brine in DAM production process - Google Patents
Method for controlling TOC in waste brine in DAM production process Download PDFInfo
- Publication number
- CN112094194A CN112094194A CN202011061719.8A CN202011061719A CN112094194A CN 112094194 A CN112094194 A CN 112094194A CN 202011061719 A CN202011061719 A CN 202011061719A CN 112094194 A CN112094194 A CN 112094194A
- Authority
- CN
- China
- Prior art keywords
- brine
- aniline
- phase
- formaldehyde
- ratio
- 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.)
- Pending
Links
- 239000012267 brine Substances 0.000 title claims abstract description 116
- HPALAKNZSZLMCH-UHFFFAOYSA-M sodium;chloride;hydrate Chemical compound O.[Na+].[Cl-] HPALAKNZSZLMCH-UHFFFAOYSA-M 0.000 title claims abstract description 116
- 238000000034 method Methods 0.000 title claims abstract description 47
- 239000002699 waste material Substances 0.000 title claims abstract description 36
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 12
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 claims abstract description 130
- PAYRUJLWNCNPSJ-UHFFFAOYSA-N Aniline Chemical compound NC1=CC=CC=C1 PAYRUJLWNCNPSJ-UHFFFAOYSA-N 0.000 claims abstract description 120
- 239000012071 phase Substances 0.000 claims abstract description 76
- 239000003513 alkali Substances 0.000 claims abstract description 43
- 229920000768 polyamine Chemical class 0.000 claims abstract description 33
- 239000012074 organic phase Substances 0.000 claims abstract description 31
- CZZYITDELCSZES-UHFFFAOYSA-N diphenylmethane Chemical class C=1C=CC=CC=1CC1=CC=CC=C1 CZZYITDELCSZES-UHFFFAOYSA-N 0.000 claims abstract description 29
- 239000000203 mixture Substances 0.000 claims abstract description 26
- 238000006482 condensation reaction Methods 0.000 claims abstract description 25
- 238000006386 neutralization reaction Methods 0.000 claims abstract description 25
- 239000012535 impurity Substances 0.000 claims abstract description 24
- 230000017105 transposition Effects 0.000 claims abstract description 20
- 150000004985 diamines Chemical class 0.000 claims abstract description 14
- 238000006462 rearrangement reaction Methods 0.000 claims abstract description 14
- 239000003377 acid catalyst Substances 0.000 claims abstract description 7
- 150000003839 salts Chemical class 0.000 claims abstract description 7
- -1 diamine salt Chemical class 0.000 claims abstract description 6
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 96
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 63
- 238000000605 extraction Methods 0.000 claims description 50
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 claims description 48
- 239000007864 aqueous solution Substances 0.000 claims description 43
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 35
- 238000005406 washing Methods 0.000 claims description 31
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 claims description 28
- TZIHFWKZFHZASV-UHFFFAOYSA-N methyl formate Chemical compound COC=O TZIHFWKZFHZASV-UHFFFAOYSA-N 0.000 claims description 18
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 claims description 14
- 235000019253 formic acid Nutrition 0.000 claims description 14
- XBDQKXXYIPTUBI-UHFFFAOYSA-M Propionate Chemical compound CCC([O-])=O XBDQKXXYIPTUBI-UHFFFAOYSA-M 0.000 claims description 11
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 claims description 10
- WBJINCZRORDGAQ-UHFFFAOYSA-N formic acid ethyl ester Natural products CCOC=O WBJINCZRORDGAQ-UHFFFAOYSA-N 0.000 claims description 9
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 8
- 230000002378 acidificating effect Effects 0.000 claims description 8
- 239000003054 catalyst Substances 0.000 claims description 8
- 239000000243 solution Substances 0.000 claims description 7
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 6
- 239000003795 chemical substances by application Substances 0.000 claims description 4
- FERIUCNNQQJTOY-UHFFFAOYSA-M Butyrate Chemical compound CCCC([O-])=O FERIUCNNQQJTOY-UHFFFAOYSA-M 0.000 claims description 2
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 2
- KXKVLQRXCPHEJC-UHFFFAOYSA-N acetic acid trimethyl ester Natural products COC(C)=O KXKVLQRXCPHEJC-UHFFFAOYSA-N 0.000 claims description 2
- 125000002490 anilino group Chemical group [H]N(*)C1=C([H])C([H])=C([H])C([H])=C1[H] 0.000 claims description 2
- YKYONYBAUNKHLG-UHFFFAOYSA-N n-Propyl acetate Natural products CCCOC(C)=O YKYONYBAUNKHLG-UHFFFAOYSA-N 0.000 claims description 2
- 229940090181 propyl acetate Drugs 0.000 claims description 2
- NQPDZGIKBAWPEJ-UHFFFAOYSA-N valeric acid Chemical compound CCCCC(O)=O NQPDZGIKBAWPEJ-UHFFFAOYSA-N 0.000 claims description 2
- 239000002585 base Substances 0.000 claims 1
- 238000007670 refining Methods 0.000 abstract description 4
- 235000011121 sodium hydroxide Nutrition 0.000 description 19
- MMCPOSDMTGQNKG-UJZMCJRSSA-N aniline;hydrochloride Chemical compound Cl.N[14C]1=[14CH][14CH]=[14CH][14CH]=[14CH]1 MMCPOSDMTGQNKG-UJZMCJRSSA-N 0.000 description 14
- FZERHIULMFGESH-UHFFFAOYSA-N N-phenylacetamide Chemical compound CC(=O)NC1=CC=CC=C1 FZERHIULMFGESH-UHFFFAOYSA-N 0.000 description 12
- 230000000052 comparative effect Effects 0.000 description 12
- 239000007795 chemical reaction product Substances 0.000 description 9
- 230000003068 static effect Effects 0.000 description 8
- BIVUUOPIAYRCAP-UHFFFAOYSA-N aminoazanium;chloride Chemical compound Cl.NN BIVUUOPIAYRCAP-UHFFFAOYSA-N 0.000 description 7
- 238000006555 catalytic reaction Methods 0.000 description 7
- 239000008098 formaldehyde solution Substances 0.000 description 7
- DYDNPESBYVVLBO-UHFFFAOYSA-N formanilide Chemical compound O=CNC1=CC=CC=C1 DYDNPESBYVVLBO-UHFFFAOYSA-N 0.000 description 7
- UPMLOUAZCHDJJD-UHFFFAOYSA-N 4,4'-Diphenylmethane Diisocyanate Chemical compound C1=CC(N=C=O)=CC=C1CC1=CC=C(N=C=O)C=C1 UPMLOUAZCHDJJD-UHFFFAOYSA-N 0.000 description 6
- 229960001413 acetanilide Drugs 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 6
- 238000007323 disproportionation reaction Methods 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 3
- 235000019439 ethyl acetate Nutrition 0.000 description 3
- 238000000746 purification Methods 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 235000011054 acetic acid Nutrition 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- MMCPOSDMTGQNKG-UHFFFAOYSA-N anilinium chloride Chemical compound Cl.NC1=CC=CC=C1 MMCPOSDMTGQNKG-UHFFFAOYSA-N 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000003153 chemical reaction reagent Substances 0.000 description 2
- ZZTCPWRAHWXWCH-UHFFFAOYSA-N diphenylmethanediamine Chemical class C=1C=CC=CC=1C(N)(N)C1=CC=CC=C1 ZZTCPWRAHWXWCH-UHFFFAOYSA-N 0.000 description 2
- 150000002148 esters Chemical class 0.000 description 2
- 230000007062 hydrolysis Effects 0.000 description 2
- 238000006460 hydrolysis reaction Methods 0.000 description 2
- VMGAPWLDMVPYIA-HIDZBRGKSA-N n'-amino-n-iminomethanimidamide Chemical compound N\N=C\N=N VMGAPWLDMVPYIA-HIDZBRGKSA-N 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 229920002635 polyurethane Polymers 0.000 description 2
- 239000004814 polyurethane Substances 0.000 description 2
- BOLDJAUMGUJJKM-LSDHHAIUSA-N renifolin D Natural products CC(=C)[C@@H]1Cc2c(O)c(O)ccc2[C@H]1CC(=O)c3ccc(O)cc3O BOLDJAUMGUJJKM-LSDHHAIUSA-N 0.000 description 2
- HLBBKKJFGFRGMU-UHFFFAOYSA-M sodium formate Chemical compound [Na+].[O-]C=O HLBBKKJFGFRGMU-UHFFFAOYSA-M 0.000 description 2
- 235000019254 sodium formate Nutrition 0.000 description 2
- 238000001179 sorption measurement Methods 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 1
- VMHLLURERBWHNL-UHFFFAOYSA-M Sodium acetate Chemical compound [Na+].CC([O-])=O VMHLLURERBWHNL-UHFFFAOYSA-M 0.000 description 1
- 239000004280 Sodium formate Substances 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- 150000001412 amines Chemical class 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 125000002485 formyl group Chemical group [H]C(*)=O 0.000 description 1
- 239000010842 industrial wastewater Substances 0.000 description 1
- 238000004811 liquid chromatography Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 239000011541 reaction mixture Substances 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 239000001632 sodium acetate Substances 0.000 description 1
- 235000017281 sodium acetate Nutrition 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000005945 translocation 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
- C07C209/00—Preparation of compounds containing amino groups bound to a carbon skeleton
- C07C209/68—Preparation of compounds containing amino groups bound to a carbon skeleton from amines, by reactions not involving amino groups, e.g. reduction of unsaturated amines, aromatisation, or substitution of the carbon skeleton
- C07C209/78—Preparation of compounds containing amino groups bound to a carbon skeleton from amines, by reactions not involving amino groups, e.g. reduction of unsaturated amines, aromatisation, or substitution of the carbon skeleton from carbonyl compounds, e.g. from formaldehyde, and amines having amino groups bound to carbon atoms of six-membered aromatic rings, with formation of methylene-diarylamines
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C209/00—Preparation of compounds containing amino groups bound to a carbon skeleton
- C07C209/82—Purification; Separation; Stabilisation; Use of additives
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention provides a method for controlling TOC in waste brine in the DAM production process, which comprises the following steps: (1) in the presence of an acid catalyst, formaldehyde and aniline undergo condensation reaction and transposition rearrangement reaction to obtain a mixture of diamine salt and polyamine salt containing diphenylmethane series; (2) adding alkali liquor into the mixture for neutralization reaction, and layering to obtain a brine phase I and an organic phase I containing diamine and polyamine of a diphenylmethane system; (3) extracting and stripping the brine phase I to obtain waste brine; after purifying and refining the organic phase, obtaining diamine and polyamine of diphenyl methane series; wherein, the molar ratio of the formaldehyde to the aniline in the step (1) is 0.3-0.6, and the total content of impurities in the formaldehyde is less than 1000 ppm; the alkali excess ratio of the neutralization reaction in the step (2) is 1.01-1.30. The method of the invention reduces the TOC content in the waste brine to 15ppm, and meets the requirement of subsequent treatment.
Description
Technical Field
The invention relates to the technical field of industrial wastewater treatment, in particular to a method for controlling byproduct waste brine TOC in a DAM production process.
Background
MDI is one of the main raw materials in the polyurethane industry. Hydrochloric acid is used as a catalyst, aniline and formaldehyde are subjected to condensation reaction to generate diamine and polyamine (DAM for short) of a diphenylmethane system, and the DAM is subjected to phosgenation reaction to generate monomer or polymeric MDI, which is a well-known method in the polyurethane industry. According to the prior art, a large amount of alkali liquor is added to neutralize the acidic polyamine salt after the condensation reaction, and the caustic soda cost accounts for nearly 10% of the DAM manufacturing cost; meanwhile, a large amount of waste brine is generated in the process, and the brine contains organic matters such as aniline, formic acid, acetic acid, polyamines and the like, so that great pressure is caused on environmental protection discharge.
Generally speaking, MDI production plants use conventional extraction and stripping processes for amine-containing waste brine, and the ZL200710013817.2 patent discloses a process for continuously extracting diamines and polyamines of the diaminodiphenylmethane series from brine, which extraction process removes polyamines from the brine. Patent CN101665302A discloses a waste brine treatment process, which utilizes an overweight rotary bed multistage extraction process to replace the traditional unipolar extraction process. The extracted brine is further treated by a steam stripping process and then oxidation and adsorption to meet the requirement of chlor-alkali recycling. Patent CN101143753A discloses a method for deeply treating MDI waste brine, which adopts oxidation and adsorption to deeply treat brine, but the method has the defects of high energy consumption, high investment, complex equipment structure and long process flow.
Therefore, further intensive research on key components affecting the TOC content is required, and a method for controlling the generation amount of the key components at the front end is developed, so that the treatment difficulty and investment of the waste brine are greatly reduced.
Disclosure of Invention
In view of the above, in order to reduce the TOC content in the waste brine discharged in the production process of DAM, the invention provides a method for controlling the TOC content in the waste brine, which achieves the purpose of reducing the TOC content in the waste brine by strictly controlling the alkali excess rate in the preparation method, and can reduce the TOC content in the waste brine to less than or equal to 15 ppm.
In order to achieve the purpose, the invention adopts the following technical scheme:
the invention provides a method for controlling TOC in waste brine in the production process of DAM, which comprises the following steps:
(1) in the presence of an acid catalyst, formaldehyde and aniline undergo condensation reaction and transposition rearrangement reaction to obtain a mixture of diamine salt and polyamine salt containing diphenylmethane series;
(2) adding alkali liquor into the mixture for neutralization reaction, and layering to obtain a brine phase I and an organic phase I containing diamine and polyamine of a diphenylmethane system;
(3) extracting and stripping the first brine phase to obtain waste brine; after the organic phase is purified and refined, diamine and polyamine of diphenylmethane series are obtained;
wherein the molar ratio of the formaldehyde to the aniline in the step (1) is 0.3-0.6, and the total content of impurities in the formaldehyde is less than 1000 ppm;
and (3) the alkali excess ratio of the neutralization reaction in the step (2) is 1.01-1.30, and the alkali excess ratio is the molar ratio of the alkali in the alkali liquor added in the step (2) to the acidic catalyst added in the step (1).
In the production process of preparing DAM, researchers of the invention find that formaldehyde as a raw material contains formic acid, acetic acid and ester impurities thereof, and formanilide and acetanilide substances generated by the reaction of excessive aniline, formic acid and acetic acid exist in a system in the reaction process of formaldehyde and aniline; however, in the subsequent neutralization reaction process, if the amount of the alkali liquor is high, the formanilide and acetanilide can be hydrolyzed (as shown in the following formulas I and II), or the excessive alkali liquor can be subjected to disproportionation reaction (as shown in the following formula III) with the residual formaldehyde in the system, so that sodium formate and sodium acetate generated in the neutralization and layering process enter a brine phase, and cannot be removed through subsequent extraction and stripping treatment, and finally, the TOC in the discharged waste brine is increased.
In the present invention, the diamine and polyamine salts of diphenylmethane series specifically refer to diamine salts of diphenylmethane series and polyamine salts of diphenylmethane series, and the diamine and polyamine of diphenylmethane series specifically refer to diamine and polyamine of diphenylmethane series (abbreviated as "DAM"), which includes a mixture of diamine compounds of diphenylmethane series or isomers thereof, and a mixture of polyamine compounds of diphenylmethane series, specifically a mixture corresponding to the following chemical structural formula:
wherein n represents an integer of 0 or more; when n ═ 0, such compounds are known as diamines of the diphenylmethane series or diaminodiphenylmethane; when n > 0, these compounds are referred to as polyamines of the diphenylmethane series.
As is well known to those skilled in the art, the following formulas I and II illustrate the hydrolysis process of formanilide and acetanilide, and the following formula III illustrates the disproportionation reaction of formaldehyde;
2HCHO+NaOH→HCOONa+CH3OH formula III
In the method of the invention, the alkali excess ratio (namely the molar ratio of the alkali in the alkali liquor to the acidic catalyst in the step (1)) in the neutralization reaction process is controlled to be 1.01-1.30, so that the formanilide substances generated in the step (1) and unreacted formaldehyde in the system are mostly present in the organic phase, and the quality of the discharged brine phase is not influenced by the purification and refining processes of the organic phase.
In some embodiments, the alkali excess ratio during the neutralization reaction in step (2) is controlled to be 1.05-1.20, such as 1.16, 1.17, 1.18, 1.19; further preferably 1.06-1.15, such as 1.07, 1.08, 1.10, 1.12, 1.13.
In some embodiments, the molar ratio of formaldehyde to aniline in step (1) is from 0.35 to 0.55, preferably from 0.4 to 0.5, such as, for example, 0.42, 0.45, 0.47, 0.49.
In the present invention, as is well known to those skilled in the art, the formaldehyde feed employed inevitably contains a certain amount of impurities, in some embodiments, less than 300ppm total impurities in the formaldehyde; specifically, the impurities in the formaldehyde comprise one or more of formic acid, acetic acid, methyl formate, ethyl formate, propyl formate, methyl acetate, ethyl acetate, or propyl acetate.
In step (1) of the process of the present invention, the molar ratio of acidic catalyst to aniline is 0.1 to 0.6, preferably 0.2 to 0.4, such as, for example, 0.25, 0.30, 0.35, 0.5; the acid catalyst can be selected from hydrochloric acid aqueous solution or sulfuric acid aqueous solution, and is preferably hydrochloric acid aqueous solution with the mass percentage concentration of 25-37%. In the present invention, the alkali excess ratio is a molar ratio of the alkali in the alkaline solution added in the step (2) to the acidic catalyst added in the step (1), wherein the molar amount of the acidic catalyst is specifically calculated by the molar amount of the hydrochloric acid in the hydrochloric acid aqueous solution or the sulfuric acid in the sulfuric acid aqueous solution.
In the specific process of the step (1), aniline and an acid catalyst are mixed to form aniline salt, and then the aniline salt is mixed with formaldehyde to carry out condensation reaction to obtain a condensation reaction product; in some embodiments, the condensation reaction is carried out at 50-70 ℃ for 1-3 h; then, the obtained condensation reaction product is continuously subjected to transposition rearrangement reaction to obtain a mixture containing diamine salt and polyamine salt of diphenylmethane series; in some embodiments, the translocation rearrangement reaction is performed at 80 to 110 ℃ for 1 to 4 hours.
In some specific implementation processes, aniline and an acid catalyst may be mixed in a static mixer for reaction, and a product obtained through a condensation reaction may be transferred to a transposition reactor for further rearrangement reaction, where the specific reactor used above belongs to a conventional experimental means in the art, and those skilled in the art also use other reactors for reaction purposes, and are not described herein again.
In a specific embodiment of the method of the present invention, the neutralization reaction in step (2) is carried out at 90-110 ℃, and the alkali solution used is selected from an aqueous sodium hydroxide solution or an aqueous potassium hydroxide solution, preferably an aqueous sodium hydroxide solution with a mass percentage concentration of 30% -55%.
In step (2) of the method of the present invention, the method further comprises a step of washing the first organic phase with water to remove water-soluble impurities contained therein; specifically, the organic phase I obtained by washing (namely washing) with water, and after combining the water phase obtained by washing with water to the brine phase I, carrying out extraction and stripping treatment in the step (3); the organic phase obtained after washing with water is subjected to purification and refining treatment in step (3). In some embodiments, the volume ratio of water to the volume of the organic phase (hereinafter referred to as the "water wash ratio") used for the water wash is 0.1 to 0.4, and in some embodiments, the organic phase may be washed with water in small amounts multiple times to sufficiently remove water-soluble impurities from the organic phase. The washing operation is a conventional technique in the art and is not described in detail herein.
In the step (3) of the method, the brine phase I and an extracting agent are extracted to obtain an extracted brine phase, and then the extracted brine phase is subjected to steam stripping treatment continuously to obtain the waste brine; in some embodiments, the extraction is performed at a volume ratio of extractant to brine phase one of 0.1 to 0.4 (hereinafter referred to as "extraction ratio"), e.g., 0.2, 0.3; specifically, the first brine phase and the extractant flow in the reverse direction in the extraction tower to fully extract; the temperature of the extraction may be in particular from 90 to 110 c, for example 95 c, 100 c, in some embodiments the extractant is selected from aniline or toluene. The extracted brine phase obtained above is subjected to stripping treatment in a stripping column, the temperature of which can be maintained at 95-110 ℃, as is well known to those skilled in the art, and the stripping treatment can be carried out by using 2 kg of pressurized steam (hereinafter referred to as 2S steam).
The organic phase obtained by washing can be further subjected to conventional purification and refining treatment in the field such as rectification, crystallization and the like to obtain diamine and polyamine (DAM) of a diphenylmethane series; in the subsequent production process, diamine and polyamine of diphenylmethane series undergo phosgenation reaction to obtain monomeric or polymeric diphenylmethane diisocyanate (MDI for short).
By adopting the technical scheme, the method has the following technical effects:
according to the method for controlling TOC (total organic carbon content) in the waste brine in the DAM production process, provided by the invention, the alkali excess rate in the neutralization reaction process is controlled to be 1.01-1.30, so that hydrolysis of formanilide and formaldehyde disproportionation caused by excessive alkali liquor in the system are avoided, formazan/acetic acid is reduced from the source, the content of formazan/acetic acid in discharged brine is reduced, the TOC content in the waste brine is reduced to 15ppm, and the requirement of subsequent treatment is met.
Detailed Description
In order to better understand the present invention, the following examples are provided to further illustrate the content of the present invention.
The following methods were used in the following examples:
(1) analysis method of impurity (formic acid, acetic acid and ester thereof) content in formyl/acetanilide and formaldehyde: adopting liquid chromatography, wherein an analytical instrument is Agilent 1200;
(2) the method for analyzing the TOC content in the waste brine comprises the following steps: the analysis was performed using a Jena N/C2100S TOC instrument.
Raw material source information in the following examples:
aniline: vanhua chemical Co., Ltd;
formaldehyde: vanhua chemical Co., Ltd;
hydrochloric acid: vanhua chemical Co., Ltd;
sodium hydroxide: vanhua chemical Co., Ltd.
Other chemical reagents used in the method of the invention all adopt reagents which are conventional in the field, and the purity is more than chemical purity.
Example 1
In this example, the mass concentration of the aqueous formaldehyde solution was 30%, wherein the impurities formic acid content was 220.0ppm, acetic acid was 15.0ppm, methyl formate was 32.5ppm, and ethyl formate was 18.2 ppm; the mass concentration of the hydrochloric acid aqueous solution is 25 percent; the mass concentration of the sodium hydroxide aqueous solution is 30 percent.
(1) Aniline and hydrochloric acid aqueous solution are mixed in a static mixer to form aniline hydrochloride, and after formaldehyde is mixed into the aniline hydrochloride, condensation reaction is carried out in a reactor for 2 hours at the temperature of 60 ℃; wherein the molar ratio of the hydrochloric acid aqueous solution (based on the molar amount of the hydrochloric acid) to the aniline is 0.10, and the molar ratio of the formaldehyde to the aniline is 0.30;
transferring the condensation reaction product into a transposition reactor, and continuously carrying out transposition rearrangement reaction for 2h at 100 ℃ under the catalysis of hydrochloric acid to obtain a mixture of diamine hydrochloride and polyamine hydrochloride containing diphenylmethane series;
(2) adding an aqueous solution of sodium hydroxide into the mixture, wherein the excess ratio of alkali is 1.01, then carrying out neutralization reaction at 90 ℃, and layering to obtain an organic phase I and a brine phase I;
washing the obtained organic phase I with water (the washing ratio is 0.30), and combining the water phase after washing with water into the brine phase I;
(3) introducing the washed brine phase I into an extraction tower from the top, and performing reverse extraction with aniline flowing in the bottom of the extraction tower to obtain an extracted brine phase; wherein the volume ratio of the aniline to the first brine phase is 0.1, and the temperature in the extraction tower is 105 ℃;
introducing the obtained extraction brine phase into a stripping tower, and carrying out stripping treatment under 2S steam (the stripping ratio is 0.1), wherein the tower top temperature of the stripping tower is 100 ℃; and after the aniline is removed from the tower top, the brine produced at the tower bottom is the treated waste brine.
Example 2
In this example, the mass concentration of the aqueous formaldehyde solution was 33%, wherein the impurities formic acid content was 220.0ppm, acetic acid was 15.0ppm, methyl formate was 32.5ppm, and ethyl formate was 18.2 ppm; the mass concentration of the hydrochloric acid aqueous solution is 25 percent; the mass concentration of the sodium hydroxide aqueous solution is 32 percent.
(1) Aniline and hydrochloric acid aqueous solution are mixed in a static mixer to form aniline hydrochloride, and after formaldehyde is mixed into the aniline hydrochloride, condensation reaction is carried out in a reactor for 2 hours at 60 ℃, wherein the molar ratio of the hydrochloric acid aqueous solution (based on the molar amount of the hydrochloric acid) to the aniline is 0.18, and the molar ratio of the formaldehyde to the aniline is 0.30;
transferring the condensation reaction product into a transposition reactor, and continuously carrying out transposition rearrangement reaction for 2h at 100 ℃ under the catalysis of hydrochloric acid to obtain a mixture of diamine hydrochloride and polyamine hydrochloride containing diphenylmethane series;
(2) adding an aqueous solution of sodium hydroxide into the mixture, wherein the excess ratio of alkali is 1.05, then carrying out neutralization reaction at 90 ℃, and layering to obtain an organic phase I and a brine phase I;
washing the obtained organic phase I with water (the washing ratio is 0.30), and combining the water phase after washing with water into the brine phase I;
(3) introducing the washed brine phase I into an extraction tower from the top, and performing reverse extraction with aniline flowing in the bottom of the extraction tower to obtain an extracted brine phase; wherein the volume ratio of the aniline to the first brine phase is 0.1, and the temperature in the extraction tower is 105 ℃;
introducing the obtained extraction brine phase into a stripping tower, and carrying out stripping treatment under 2S steam (the stripping ratio is 0.1), wherein the tower top temperature of the stripping tower is 100 ℃; and after the aniline is removed from the tower top, the brine produced at the tower bottom is the treated waste brine.
Example 3
In this example, the mass concentration of the aqueous formaldehyde solution was 45%, wherein the impurities formic acid content was 220.0ppm, acetic acid was 15.0ppm, methyl formate was 32.5ppm, and ethyl formate was 18.2 ppm; the mass concentration of the hydrochloric acid aqueous solution is 34 percent; the mass concentration of the sodium hydroxide aqueous solution is 40 percent.
(1) Aniline and hydrochloric acid aqueous solution are mixed in a static mixer to form aniline hydrochloride, and after formaldehyde is mixed into the aniline hydrochloride, condensation reaction is carried out in a reactor for 2 hours at 60 ℃, wherein the molar ratio of the hydrochloric acid aqueous solution (based on the molar amount of the hydrochloric acid) to the aniline is 0.23, and the molar ratio of the formaldehyde to the aniline is 0.48;
transferring the condensation reaction product into a transposition reactor, and continuously carrying out transposition rearrangement reaction for 2h at 100 ℃ under the catalysis of hydrochloric acid to obtain a mixture of diamine hydrochloride and polyamine hydrochloride containing diphenylmethane series;
(2) adding an aqueous solution of sodium hydroxide into the mixture, wherein the excess alkali ratio is 1.08, then carrying out neutralization reaction at 90 ℃, and layering to obtain an organic phase I and a brine phase I;
washing the obtained organic phase I with water (the washing ratio is 0.30), and combining the water phase after washing with water into the brine phase I;
(3) introducing the washed brine phase I into an extraction tower from the top, and performing reverse extraction with aniline flowing in the bottom of the extraction tower to obtain an extracted brine phase; wherein the volume ratio of the aniline to the first brine phase is 0.1, and the temperature in the extraction tower is 105 ℃;
introducing the obtained extraction brine phase into a stripping tower, and carrying out stripping treatment under 2S steam (the stripping ratio is 0.1), wherein the tower top temperature of the stripping tower is 100 ℃; and after the aniline is removed from the tower top, the brine produced at the tower bottom is the treated waste brine.
Example 4
In this example, the mass concentration of the aqueous formaldehyde solution was 40%, wherein the impurities formic acid content was 220.0ppm, acetic acid was 15.0ppm, methyl formate was 32.5ppm, and ethyl formate was 18.2 ppm; the mass concentration of the hydrochloric acid aqueous solution is 28 percent; the mass concentration of the sodium hydroxide aqueous solution is 45 percent.
(1) Aniline and hydrochloric acid aqueous solution are mixed in a static mixer to form aniline hydrochloride, and after formaldehyde is mixed into the aniline hydrochloride, condensation reaction is carried out in a reactor for 2 hours at the temperature of 60 ℃; wherein the molar ratio of the hydrochloric acid aqueous solution (based on the molar amount of the hydrochloric acid) to the aniline is 0.41, and the molar ratio of the formaldehyde to the aniline is 0.40;
transferring the condensation reaction product into a transposition reactor, and continuously carrying out transposition rearrangement reaction for 2h at 100 ℃ under the catalysis of hydrochloric acid to obtain a mixture of diamine hydrochloride and polyamine hydrochloride containing diphenylmethane series;
(2) adding an aqueous solution of sodium hydroxide into the mixture, wherein the excess ratio of alkali is 1.15, then carrying out neutralization reaction at 90 ℃, and layering to obtain an organic phase I and a brine phase I;
washing the obtained organic phase I with water (the washing ratio is 0.30), and combining the water phase after washing with water into the brine phase I;
(3) introducing the washed brine phase I into an extraction tower from the top, and performing reverse extraction with aniline flowing in the bottom of the extraction tower to obtain an extracted brine phase; wherein the volume ratio of the aniline to the first brine phase is 0.1, and the temperature in the extraction tower is 105 ℃;
introducing the obtained extraction brine phase into a stripping tower, and carrying out stripping treatment under 2S steam (the stripping ratio is 0.1), wherein the tower top temperature of the stripping tower is 100 ℃; and after the aniline is removed from the tower top, the brine produced at the tower bottom is the treated waste brine.
Example 5
In this example, the mass concentration of the aqueous formaldehyde solution was 50%, wherein the impurities formic acid content was 220.0ppm, acetic acid was 15.0ppm, methyl formate was 32.5ppm, and ethyl formate was 18.2 ppm; the mass concentration of the hydrochloric acid aqueous solution is 36 percent; the mass concentration of the sodium hydroxide aqueous solution is 40 percent.
(1) Aniline and hydrochloric acid aqueous solution are mixed in a static mixer to form aniline hydrochloride, and after formaldehyde is mixed into the aniline hydrochloride, condensation reaction is carried out in a reactor for 2 hours at the temperature of 60 ℃; wherein the molar ratio of the hydrochloric acid aqueous solution (based on the molar amount of the hydrochloric acid) to the aniline is 0.10, and the molar ratio of the formaldehyde to the aniline is 0.53;
transferring the condensation reaction product into a transposition reactor, and continuously carrying out transposition rearrangement reaction for 2h at 100 ℃ under the catalysis of hydrochloric acid to obtain a mixture of diamine hydrochloride and polyamine hydrochloride containing diphenylmethane series;
(2) adding an aqueous solution of sodium hydroxide into the mixture, wherein the excess ratio of alkali is 1.20, then carrying out neutralization reaction at 90 ℃, and layering to obtain an organic phase I and a brine phase I;
washing the obtained organic phase I with water (the washing ratio is 0.30), and combining the water phase after washing with water into the brine phase I;
(3) introducing the washed brine phase I into an extraction tower from the top, and performing reverse extraction with aniline flowing in the bottom of the extraction tower to obtain an extracted brine phase; wherein the volume ratio of the aniline to the first brine phase is 0.1, and the temperature in the extraction tower is 105 ℃;
introducing the obtained extraction brine phase into a stripping tower, and carrying out stripping treatment under 2S steam (the stripping ratio is 0.1), wherein the tower top temperature of the stripping tower is 100 ℃; and after the aniline is removed from the tower top, the brine produced at the tower bottom is the treated waste brine.
Example 6
In this example, the mass concentration of the aqueous formaldehyde solution was 48%, wherein the impurities formic acid content was 220.0ppm, acetic acid was 15.0ppm, methyl formate was 32.5ppm, and ethyl formate was 18.2 ppm; the mass concentration of the hydrochloric acid aqueous solution is 35 percent; the mass concentration of the sodium hydroxide aqueous solution is 50 percent.
(1) Aniline and hydrochloric acid aqueous solution are mixed in a static mixer to form aniline hydrochloride, and after formaldehyde is mixed into the aniline hydrochloride, condensation reaction is carried out in a reactor for 2 hours at the temperature of 60 ℃; wherein the molar ratio of the hydrochloric acid aqueous solution (based on the molar amount of the hydrochloric acid) to the aniline is 0.60, and the molar ratio of the formaldehyde to the aniline is 0.60;
transferring the condensation reaction product into a transposition reactor, and continuously carrying out transposition rearrangement reaction for 2h at 100 ℃ under the catalysis of hydrochloric acid to obtain a mixture of diamine hydrochloride and polyamine hydrochloride containing diphenylmethane series;
(2) adding an aqueous solution of sodium hydroxide into the mixture, wherein the excess ratio of alkali is 1.30, then carrying out neutralization reaction at 90 ℃, and layering to obtain an organic phase I and a brine phase I;
washing the obtained organic phase I with water (the washing ratio is 0.30), and combining the water phase after washing with water into the brine phase I;
(3) introducing the washed brine phase I into an extraction tower from the top, and performing reverse extraction with aniline flowing in the bottom of the extraction tower to obtain an extracted brine phase; wherein the volume ratio of the aniline to the first brine phase is 0.1, and the temperature in the extraction tower is 105 ℃;
introducing the obtained extraction brine phase into a stripping tower, and carrying out stripping treatment under 2S steam (the stripping ratio is 0.1), wherein the tower top temperature of the stripping tower is 100 ℃; and after the aniline is removed from the tower top, the brine produced at the tower bottom is the treated waste brine.
Example 7
In this example, the mass concentration of the aqueous formaldehyde solution was 50%, wherein the impurity formic acid content was 650.3ppm, the acetic acid content was 28.2ppm, the methyl formate content was 102.8ppm, and the ethyl formate content was 30.5 ppm; the mass concentration of the hydrochloric acid aqueous solution is 36 percent; the mass concentration of the sodium hydroxide aqueous solution is 50 percent.
(1) Aniline and hydrochloric acid aqueous solution are mixed in a static mixer to form aniline hydrochloride, and after formaldehyde is mixed into the aniline hydrochloride, condensation reaction is carried out in a reactor for 2 hours at the temperature of 60 ℃; wherein the molar ratio of the hydrochloric acid aqueous solution (based on the molar amount of the hydrochloric acid) to the aniline is 0.41, and the molar ratio of the formaldehyde to the aniline is 0.60;
transferring the condensation reaction product into a transposition reactor, and continuously carrying out transposition rearrangement reaction for 2h at 100 ℃ under the catalysis of hydrochloric acid to obtain a mixture of diamine hydrochloride and polyamine hydrochloride containing diphenylmethane series;
(2) adding an aqueous solution of sodium hydroxide into the polyamine hydrochloride, wherein the excess alkali ratio is 1.08, then carrying out neutralization reaction at 90 ℃, and layering to obtain an organic phase I and a brine phase I;
washing the obtained organic phase I with water (the washing ratio is 0.30), and combining the water phase after washing with water into the brine phase I;
(3) introducing the washed brine phase I into an extraction tower from the top, and performing reverse extraction with aniline flowing in the bottom of the extraction tower to obtain an extracted brine phase; wherein the volume ratio of the aniline to the first brine phase is 0.1, and the temperature in the extraction tower is 105 ℃;
introducing the obtained extraction brine phase into a stripping tower, and carrying out stripping treatment under 2S steam (the stripping ratio is 0.1), wherein the tower top temperature of the stripping tower is 100 ℃; and after the aniline is removed from the tower top, the brine produced at the tower bottom is the treated waste brine.
Comparative example 1
This comparative example differs from example 6 only in that the alkali excess ratio in step (2) is 1.40;
comparative example 2
This comparative example differs from example 6 only in that the alkali excess ratio in step (2) is 1.50.
Comparative example 3
This comparative example differs from example 6 only in that the alkali excess ratio in step (2) is 1.60.
Comparative example 4
This comparative example differs from example 6 only in that the alkali excess ratio in step (2) is 0.90.
The contents of impurities in the mixture obtained in step (1), the brine phase one obtained in step (2) and the waste brine obtained in step (3) in the above examples and comparative examples are shown in tables 1 to 3 below.
TABLE 1 impurity content (ppm) in the mixture obtained in step (1)
TABLE 2 content of impurities (ppm) in brine phase one
Note: in the table, "/" indicates that no corresponding component was detected.
TABLE 3 impurity content (ppm) in waste brine
Note: in the table, "/" indicates that no corresponding component was detected.
As can be seen from the above data, in each example, the sum of the contents of formanilide and acetanilide in the mixture obtained in step (1) is greater than 100ppm, but the process of the present invention controls the excess alkali ratio of the neutralization reaction to be between 1.01 and 1.30, so that the contents of formic acid and acetic acid in the waste brine obtained are less than 35ppm and the TOC content is less than 15 ppm.
As can be seen from the comparative examples, in comparative examples 1 to 3, the excess alkali ratio used in the neutralization reaction is more than 1.30, the disproportionation reaction of the residual formaldehyde in the reaction mixture of the polyamine hydrochloride and the excess alkali solution during the neutralization reaction occurs, and the formanilide and acetanilide present in the system are hydrolyzed in the alkaline environment, resulting in the increase of the TOC content in the waste brine. In the comparative example 4, the alkali excess ratio is 0.90, the neutralization reaction is not completely carried out, the corrosion to subsequent treatment (extraction) equipment is easily caused, and the safety risk exists, so that corresponding detection data are not given; however, it is reasonably expected that the neutralization reaction with an excess alkali ratio of 0.9 does not proceed to completion, and the polyamine hydrochloride will be present in the first brine phase, resulting in an increase in the impurity content of the first brine phase.
Finally, it should be noted that the above-mentioned embodiments only illustrate the preferred embodiments of the present invention, and do not limit the scope of the present invention, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that various changes and modifications can be made by modifying the technical solution of the present invention or equivalent substitutions within the scope of the present invention defined by the claims.
Claims (10)
1. A method for controlling TOC in waste brine in the production of DAM, comprising the steps of:
(1) in the presence of an acid catalyst, formaldehyde and aniline undergo condensation reaction and transposition rearrangement reaction to obtain a mixture of diamine salt and polyamine salt containing diphenylmethane series;
(2) adding alkali liquor into the mixture for neutralization reaction, and layering to obtain a brine phase I and an organic phase I containing diamine and polyamine of a diphenylmethane system;
(3) extracting and stripping the first brine phase to obtain waste brine; after the organic phase is purified and refined, diamine and polyamine of diphenylmethane series are obtained;
wherein the molar ratio of the formaldehyde to the aniline in the step (1) is 0.3-0.6, and the total content of impurities in the formaldehyde is less than 1000 ppm;
and (3) the alkali excess ratio of the neutralization reaction in the step (2) is 1.01-1.30, and the alkali excess ratio is the molar ratio of the alkali in the alkali liquor added in the step (2) to the acidic catalyst added in the step (1).
2. The method according to claim 1, wherein the base excess ratio is 1.05-1.20, preferably 1.06-1.15.
3. The process according to claim 1 or 2, characterized in that in step (1), the molar ratio of formaldehyde to aniline is 0.35-0.55;
the content of impurities in the formaldehyde is less than 300 ppm;
the impurities in the formaldehyde comprise one or more of formic acid, acetic acid, methyl formate, ethyl formate, propyl formate, methyl acetate, ethyl acetate, or propyl acetate.
4. The process according to claim 3, wherein the molar ratio of acidic catalyst to aniline in step (1) is from 0.1 to 0.6, preferably from 0.2 to 0.4;
the acid catalyst is selected from a hydrochloric acid aqueous solution or a sulfuric acid aqueous solution, and is preferably a hydrochloric acid aqueous solution with the mass percentage concentration of 25% -37%.
5. The method according to any one of claims 1 to 4, wherein the condensation reaction in step (1) is carried out at 50 to 70 ℃ for 1 to 3 hours, and the transposition rearrangement reaction is carried out at 80 to 110 ℃ for 1 to 4 hours.
6. The method according to any one of claims 1 to 5, wherein in the step (2), the neutralization reaction is carried out at 90-110 ℃, and the alkali liquor is selected from an aqueous sodium hydroxide solution or an aqueous potassium hydroxide solution, preferably an aqueous sodium hydroxide solution with a mass percentage concentration of 30-55%.
7. The method according to claim 6, wherein the step (2) further comprises a step of washing the first organic phase with water, and combining the water phase obtained after the washing with water to the first brine phase;
preferably, the volume ratio of the water used for the water washing to the first organic phase is 0.1-0.4.
8. The method according to any one of claims 1 to 7, wherein in the step (3), the extracted brine phase is obtained by performing the extraction on the brine phase I and an extracting agent, and the waste brine is obtained after the stripping treatment is continuously performed on the extracted brine phase; wherein the volume ratio of the extracting agent to the first brine phase is 0.1-0.4.
9. The method of claim 8, wherein the extractant flows counter-currently to the brine phase in the extraction column for extraction; the extraction temperature is 90-110 ℃, and the extracting agent is selected from aniline or toluene.
10. The method according to claim 8, characterized in that the stripping treatment is carried out in a stripping column, the overhead temperature of which stripping column in the stripping treatment is preferably 95-110 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011061719.8A CN112094194A (en) | 2020-09-30 | 2020-09-30 | Method for controlling TOC in waste brine in DAM production process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011061719.8A CN112094194A (en) | 2020-09-30 | 2020-09-30 | Method for controlling TOC in waste brine in DAM production process |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112094194A true CN112094194A (en) | 2020-12-18 |
Family
ID=73782935
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011061719.8A Pending CN112094194A (en) | 2020-09-30 | 2020-09-30 | Method for controlling TOC in waste brine in DAM production process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112094194A (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113929596A (en) * | 2021-11-11 | 2022-01-14 | 万华化学集团股份有限公司 | Comprehensive utilization process and stability control method of PMDI wastewater |
| CN115181027A (en) * | 2022-07-25 | 2022-10-14 | 万华化学集团股份有限公司 | Method for controlling refractory aniline impurities in waste brine in DAM production process |
| WO2025086031A1 (en) * | 2023-10-23 | 2025-05-01 | 万华化学集团股份有限公司 | Method for preparing diphenylmethane-based diamines and polyamines |
| WO2025086202A1 (en) * | 2023-10-26 | 2025-05-01 | 万华化学集团股份有限公司 | Preparation method for diamines and polyamines of diphenylmethane series that improve 2,4-mda selectivity |
| WO2025118188A1 (en) * | 2023-12-06 | 2025-06-12 | 万华化学集团股份有限公司 | Method for preparing diphenylmethane-based diamine and polyamine |
| WO2025123218A1 (en) * | 2023-12-12 | 2025-06-19 | 万华化学集团股份有限公司 | Preparation method for diamines and polyamines of the diphenylmethane series |
| WO2025145419A1 (en) * | 2024-01-05 | 2025-07-10 | 万华化学集团股份有限公司 | Preparation method for diphenylmethane series diamine and polyamine |
| WO2025152114A1 (en) * | 2024-01-18 | 2025-07-24 | 万华化学集团股份有限公司 | Method for reducing toc content in salt-containing organic wastewater generated in dam preparation process |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101665302A (en) * | 2009-09-17 | 2010-03-10 | 宁波万华聚氨酯有限公司 | Processing method of effluent brine produced in MDI production process |
| CN101679203A (en) * | 2007-06-04 | 2010-03-24 | 亨茨曼国际有限公司 | Process for preparing di-and polyamines of the diphenylmethane series |
| US20110065960A1 (en) * | 2008-05-26 | 2011-03-17 | Basf Se | Method for producing diphenylmethane diamine |
| CN107827756A (en) * | 2017-11-17 | 2018-03-23 | 万华化学集团股份有限公司 | A kind of preparation method and device and catalyst of the diphenylmethane series diamines and polyamines of low N methyl impurity content |
-
2020
- 2020-09-30 CN CN202011061719.8A patent/CN112094194A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101679203A (en) * | 2007-06-04 | 2010-03-24 | 亨茨曼国际有限公司 | Process for preparing di-and polyamines of the diphenylmethane series |
| US20110065960A1 (en) * | 2008-05-26 | 2011-03-17 | Basf Se | Method for producing diphenylmethane diamine |
| CN102046588A (en) * | 2008-05-26 | 2011-05-04 | 巴斯夫欧洲公司 | Method for producing diphenylmethane diamine |
| CN101665302A (en) * | 2009-09-17 | 2010-03-10 | 宁波万华聚氨酯有限公司 | Processing method of effluent brine produced in MDI production process |
| CN107827756A (en) * | 2017-11-17 | 2018-03-23 | 万华化学集团股份有限公司 | A kind of preparation method and device and catalyst of the diphenylmethane series diamines and polyamines of low N methyl impurity content |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113929596A (en) * | 2021-11-11 | 2022-01-14 | 万华化学集团股份有限公司 | Comprehensive utilization process and stability control method of PMDI wastewater |
| CN113929596B (en) * | 2021-11-11 | 2023-09-19 | 万华化学集团股份有限公司 | Comprehensive utilization process and stability control method of PMDI wastewater |
| CN115181027A (en) * | 2022-07-25 | 2022-10-14 | 万华化学集团股份有限公司 | Method for controlling refractory aniline impurities in waste brine in DAM production process |
| CN115181027B (en) * | 2022-07-25 | 2023-09-22 | 万华化学集团股份有限公司 | Method for controlling refractory aniline impurities in waste brine in DAM production process |
| WO2024021969A1 (en) * | 2022-07-25 | 2024-02-01 | 万华化学集团股份有限公司 | Method for controlling aniline impurities that are difficult to treat in waste brine in dam production process |
| WO2025086031A1 (en) * | 2023-10-23 | 2025-05-01 | 万华化学集团股份有限公司 | Method for preparing diphenylmethane-based diamines and polyamines |
| WO2025086202A1 (en) * | 2023-10-26 | 2025-05-01 | 万华化学集团股份有限公司 | Preparation method for diamines and polyamines of diphenylmethane series that improve 2,4-mda selectivity |
| WO2025118188A1 (en) * | 2023-12-06 | 2025-06-12 | 万华化学集团股份有限公司 | Method for preparing diphenylmethane-based diamine and polyamine |
| WO2025123218A1 (en) * | 2023-12-12 | 2025-06-19 | 万华化学集团股份有限公司 | Preparation method for diamines and polyamines of the diphenylmethane series |
| WO2025145419A1 (en) * | 2024-01-05 | 2025-07-10 | 万华化学集团股份有限公司 | Preparation method for diphenylmethane series diamine and polyamine |
| WO2025152114A1 (en) * | 2024-01-18 | 2025-07-24 | 万华化学集团股份有限公司 | Method for reducing toc content in salt-containing organic wastewater generated in dam preparation process |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112094194A (en) | Method for controlling TOC in waste brine in DAM production process | |
| CN107827756B (en) | Preparation method and device of diphenylmethane series diamine and polyamine with low N-methyl impurity content and catalyst | |
| KR100612922B1 (en) | A process for producing 4-aminodiphenylamine | |
| KR20070082896A (en) | How to prepare aniline | |
| JP5897148B2 (en) | Method for producing choline hydroxide | |
| CN115181027B (en) | Method for controlling refractory aniline impurities in waste brine in DAM production process | |
| CN101679203A (en) | Process for preparing di-and polyamines of the diphenylmethane series | |
| CN111960952B (en) | Method for improving quality of waste brine in DAM preparation process | |
| WO2022067747A1 (en) | Method for controlling toc in effluent brine in dam production process | |
| KR20100136430A (en) | Process for the preparation of aromatic amines | |
| CN115745809B (en) | A method for preparing diphenylmethane series diamines and polyamines with low impurity content and low by-product amount | |
| CN112279441A (en) | Treatment method of drained water generated in MDA preparation process | |
| CN113233986A (en) | Method for removing salt from condensation liquid in water phase in RT base production | |
| US9771291B2 (en) | Process for working up waste water from nitrobenzene preparation | |
| CN115745810A (en) | Preparation method of diamine and polyamine of diphenylmethane series with low Na content | |
| CN114315592A (en) | Method for recycling alkali and desalting without desalting agent in RT base production | |
| CN102417265B (en) | Method for effectively removing organic matters in wastewater from nitrochlorobenzene production | |
| CN117886702A (en) | Preparation method of di-amine and polyamine of diphenyl methane series | |
| CN111910207B (en) | Preparation method of low-color-number DAM (methyl Diphenyl methane diisocyanate), preparation method of MDI (diphenyl methane diisocyanate) and low-color-number MDI | |
| CN117510342A (en) | Preparation method of diphenylmethane series diamines and polyamines to improve 2,4-MDA selectivity | |
| CN110803818A (en) | Acetonitrile-containing wastewater treatment method | |
| CN115888349A (en) | Device and method for tail gas treatment and methanol recovery | |
| CN107585903B (en) | Method for treating and recycling dilute brine containing sodium carbonate and sodium hypochlorite | |
| CN116836147B (en) | Preparation method and application of cyclic sulfate | |
| CN115894275B (en) | Synthesis method of N, N-dialkyl-3-alkoxypropionamide |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |