GB1567638A - Process the production of polyaryl amines containing methylene bridges - Google Patents
Process the production of polyaryl amines containing methylene bridges Download PDFInfo
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- GB1567638A GB1567638A GB46742/76A GB4674276A GB1567638A GB 1567638 A GB1567638 A GB 1567638A GB 46742/76 A GB46742/76 A GB 46742/76A GB 4674276 A GB4674276 A GB 4674276A GB 1567638 A GB1567638 A GB 1567638A
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- aryl amine
- salt
- aniline
- exchange
- amine
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- 238000000034 method Methods 0.000 title claims description 83
- 150000001412 amines Chemical class 0.000 title claims description 20
- 238000004519 manufacturing process Methods 0.000 title claims description 8
- 150000004982 aromatic amines Chemical class 0.000 claims description 85
- PAYRUJLWNCNPSJ-UHFFFAOYSA-N Aniline Chemical compound NC1=CC=CC=C1 PAYRUJLWNCNPSJ-UHFFFAOYSA-N 0.000 claims description 82
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 claims description 45
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 37
- 229920000768 polyamine Polymers 0.000 claims description 29
- 150000003839 salts Chemical class 0.000 claims description 28
- 239000000203 mixture Substances 0.000 claims description 24
- 239000002253 acid Substances 0.000 claims description 21
- 239000012266 salt solution Substances 0.000 claims description 21
- 239000008346 aqueous phase Substances 0.000 claims description 17
- 238000009833 condensation Methods 0.000 claims description 16
- 230000005494 condensation Effects 0.000 claims description 16
- 239000000243 solution Substances 0.000 claims description 16
- 239000012071 phase Substances 0.000 claims description 15
- 239000012074 organic phase Substances 0.000 claims description 14
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 12
- 239000002904 solvent Substances 0.000 claims description 12
- 239000003377 acid catalyst Substances 0.000 claims description 11
- 230000002209 hydrophobic effect Effects 0.000 claims description 11
- 150000007513 acids Chemical class 0.000 claims description 10
- 238000009434 installation Methods 0.000 claims description 10
- 238000002156 mixing Methods 0.000 claims description 10
- AFVFQIVMOAPDHO-UHFFFAOYSA-N Methanesulfonic acid Chemical compound CS(O)(=O)=O AFVFQIVMOAPDHO-UHFFFAOYSA-N 0.000 claims description 9
- -1 arylamine salt Chemical class 0.000 claims description 8
- 238000005406 washing Methods 0.000 claims description 7
- DTQVDTLACAAQTR-UHFFFAOYSA-N Trifluoroacetic acid Chemical compound OC(=O)C(F)(F)F DTQVDTLACAAQTR-UHFFFAOYSA-N 0.000 claims description 6
- 239000007858 starting material Substances 0.000 claims description 6
- RNVCVTLRINQCPJ-UHFFFAOYSA-N o-toluidine Chemical compound CC1=CC=CC=C1N RNVCVTLRINQCPJ-UHFFFAOYSA-N 0.000 claims description 5
- OJGMBLNIHDZDGS-UHFFFAOYSA-N N-Ethylaniline Chemical group CCNC1=CC=CC=C1 OJGMBLNIHDZDGS-UHFFFAOYSA-N 0.000 claims description 4
- 238000010790 dilution Methods 0.000 claims description 4
- 239000012895 dilution Substances 0.000 claims description 4
- 238000004064 recycling Methods 0.000 claims description 3
- 238000007865 diluting Methods 0.000 claims description 2
- 239000007864 aqueous solution Substances 0.000 description 11
- 238000011282 treatment Methods 0.000 description 9
- 238000007792 addition Methods 0.000 description 8
- 239000003054 catalyst Substances 0.000 description 8
- 238000000605 extraction Methods 0.000 description 8
- MMCPOSDMTGQNKG-UHFFFAOYSA-N anilinium chloride Chemical compound Cl.NC1=CC=CC=C1 MMCPOSDMTGQNKG-UHFFFAOYSA-N 0.000 description 7
- 230000000694 effects Effects 0.000 description 6
- MVPPADPHJFYWMZ-UHFFFAOYSA-N chlorobenzene Chemical compound ClC1=CC=CC=C1 MVPPADPHJFYWMZ-UHFFFAOYSA-N 0.000 description 5
- 238000004809 thin layer chromatography Methods 0.000 description 5
- RFFLAFLAYFXFSW-UHFFFAOYSA-N 1,2-dichlorobenzene Chemical compound ClC1=CC=CC=C1Cl RFFLAFLAYFXFSW-UHFFFAOYSA-N 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- 238000006386 neutralization reaction Methods 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- 230000002411 adverse Effects 0.000 description 3
- GGFOZRQCNXQCLO-UHFFFAOYSA-N aniline;methanesulfonic acid Chemical class CS(O)(=O)=O.NC1=CC=CC=C1 GGFOZRQCNXQCLO-UHFFFAOYSA-N 0.000 description 3
- 230000008707 rearrangement Effects 0.000 description 3
- UFFBMTHBGFGIHF-UHFFFAOYSA-N 2,6-dimethylaniline Chemical compound CC1=CC=CC(C)=C1N UFFBMTHBGFGIHF-UHFFFAOYSA-N 0.000 description 2
- JJYPMNFTHPTTDI-UHFFFAOYSA-N 3-methylaniline Chemical compound CC1=CC=CC(N)=C1 JJYPMNFTHPTTDI-UHFFFAOYSA-N 0.000 description 2
- HEDRZPFGACZZDS-UHFFFAOYSA-N Chloroform Chemical compound ClC(Cl)Cl HEDRZPFGACZZDS-UHFFFAOYSA-N 0.000 description 2
- AFBPFSWMIHJQDM-UHFFFAOYSA-N N-methylaniline Chemical compound CNC1=CC=CC=C1 AFBPFSWMIHJQDM-UHFFFAOYSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 239000002585 base Substances 0.000 description 2
- 239000007859 condensation product Substances 0.000 description 2
- 230000008030 elimination Effects 0.000 description 2
- 238000003379 elimination reaction Methods 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 229910052500 inorganic mineral Inorganic materials 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical class C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 239000011707 mineral Substances 0.000 description 2
- 239000012044 organic layer Substances 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- VOZKAJLKRJDJLL-UHFFFAOYSA-N 2,4-diaminotoluene Chemical compound CC1=CC=C(N)C=C1N VOZKAJLKRJDJLL-UHFFFAOYSA-N 0.000 description 1
- WKBALTUBRZPIPZ-UHFFFAOYSA-N 2,6-di(propan-2-yl)aniline Chemical compound CC(C)C1=CC=CC(C(C)C)=C1N WKBALTUBRZPIPZ-UHFFFAOYSA-N 0.000 description 1
- FOYHNROGBXVLLX-UHFFFAOYSA-N 2,6-diethylaniline Chemical compound CCC1=CC=CC(CC)=C1N FOYHNROGBXVLLX-UHFFFAOYSA-N 0.000 description 1
- BMYNFMYTOJXKLE-UHFFFAOYSA-N 3-azaniumyl-2-hydroxypropanoate Chemical compound NCC(O)C(O)=O BMYNFMYTOJXKLE-UHFFFAOYSA-N 0.000 description 1
- YBRVSVVVWCFQMG-UHFFFAOYSA-N 4,4'-diaminodiphenylmethane Chemical compound C1=CC(N)=CC=C1CC1=CC=C(N)C=C1 YBRVSVVVWCFQMG-UHFFFAOYSA-N 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 1
- 150000001338 aliphatic hydrocarbons Chemical class 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 150000004996 alkyl benzenes Chemical class 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 150000003863 ammonium salts Chemical class 0.000 description 1
- 150000004945 aromatic hydrocarbons Chemical class 0.000 description 1
- JXLHNMVSKXFWAO-UHFFFAOYSA-N azane;7-fluoro-2,1,3-benzoxadiazole-4-sulfonic acid Chemical compound N.OS(=O)(=O)C1=CC=C(F)C2=NON=C12 JXLHNMVSKXFWAO-UHFFFAOYSA-N 0.000 description 1
- 238000010923 batch production Methods 0.000 description 1
- SRSXLGNVWSONIS-UHFFFAOYSA-N benzenesulfonic acid Chemical compound OS(=O)(=O)C1=CC=CC=C1 SRSXLGNVWSONIS-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 150000008280 chlorinated hydrocarbons Chemical class 0.000 description 1
- WORJEOGGNQDSOE-UHFFFAOYSA-N chloroform;methanol Chemical compound OC.ClC(Cl)Cl WORJEOGGNQDSOE-UHFFFAOYSA-N 0.000 description 1
- 238000006482 condensation reaction Methods 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- ZZTCPWRAHWXWCH-UHFFFAOYSA-N diphenylmethanediamine Chemical class C=1C=CC=CC=1C(N)(N)C1=CC=CC=C1 ZZTCPWRAHWXWCH-UHFFFAOYSA-N 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 238000005191 phase separation Methods 0.000 description 1
- 239000011541 reaction mixture Substances 0.000 description 1
- 239000000741 silica gel Substances 0.000 description 1
- 229910002027 silica gel Inorganic materials 0.000 description 1
- 239000001117 sulphuric acid Substances 0.000 description 1
- 235000011149 sulphuric acid Nutrition 0.000 description 1
- ITMCEJHCFYSIIV-UHFFFAOYSA-N triflic acid Chemical compound OS(=O)(=O)C(F)(F)F ITMCEJHCFYSIIV-UHFFFAOYSA-N 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
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G12/00—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen
- C08G12/02—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes
- C08G12/04—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes with acyclic or carbocyclic compounds
- C08G12/06—Amines
- C08G12/08—Amines aromatic
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/582—Recycling of unreacted starting or intermediate materials
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Health & Medical Sciences (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Phenolic Resins Or Amino Resins (AREA)
Description
(54) A PROCESS FOR THE PRODUCTION OF POLYARYL
AMINES CONTAINING METHYLENE BRIDGES
(71) 1, EFIM BILLER of
Dufourstrasse 42, Zurich, Switzerland, of
Austrian nationality, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement:
This invention relates to a process for the production of polyaryl amines containing methylene bridges.
The production of polyamines of the diamino-diphenyl methane series by condensing aromatic amines with formaldehyde in the presence of acid catalysts has been repeatedly described and gives products differing in composition according to the procedure adopted. Thus, condensation in the presence of weakly acid catalysts or in the presence of traces of strongly acid catalysts gives polyamine mixtures with a high content of 2,4'diaminodiaryl methanes, whereas polyamines with a high content of 4,4'diaminodiaryl methanes and, at the same time, a low content of 2,4'-isomers can only be produced in the presence of relatively large quantities of strongly acid catalysts.
For the second of these two cases, it is best to use strong mineral acids, especially hydrochloric acid (DOS No. 1,518,406;
DOS No. 2,045,834; DOS No. 2,049,707;
DOS No. 2,301,554; US-PS No. 3,367,969).
In conventional processes, however, the advantage of the high selectivity of strongly acid mineral acids for the formation of 4,4'isomers is obtained at the expense of the loss of the catalyst because, on completion of the reaction, the catalyst has to be removed from the reaction mixture by neutralisation with a base which is expensive. Another disadvantage of conventional processes is the fact that the salt solutions obtained by this neutralisation
cannot be put to any worthwhile
commercial use and thus give rise to
considerable pollution problems.
It has surprisingly been found that, when
aqueous polyamine product solutions are
mixed with starting aryl amines (aryl
amines), two phases are formed, namely an
organic phase (polyaryl amine-aryl) and an
aqueous phase (aryl amine salt solution), in which the polyamines are displaced from the aqueous phase and replaced by aryl amines.
Accordingly, the present invention relates to a process for the production of polyarylamines containing methylene bridges, in which a methylene-bridged polyarylamine salt solution, produced by the condensation of arylamines and formaldehyde in the presence of acids and water, is exchanged with a further quantity of arylamine starting material, by mixing the polyarylamine salt solution with the further quantity of arylamine starting material in one or more stages, to form a heterogeneous system, allowing the polyarylamine salt and the arylamine to react together, then separating the aqueous phase and the organic phase and recycling the aqueous aryl amine salt phase to the condensation process.
The condensation reaction which takes place in the continuous or batch process according to the invention may be carried out by conventional methods, the molar ratios of aryl amine to formaldehyde and aryl amine to acid catalyst being variable within wide limits. The molar ratio of aryl amine to formaldehyde is advantageously in the range of from 10:1 to 1:1 and preferably in the range from 4:1 to 1.8:1, whilst the molar ratio of aryl amine to catalyst is in the range of from 20:1 to 1:1 and preferably in the range from 1:1 to 5:1, this particular molar ratio being the molar ratio of aryl amine introduced at the beginning of the process to the acid present in the reaction cycle in the form of aryl amine salts. The volume ratio of organic phase to aqueous phase in each stage is preferably from 20:1 to 1:10.
In practice, the exchange is effected by repeatedly mixing the produced aqueous polyamine salt solutions with fresh starting aryl amine, preferably continuously, in countercurrent flow.
Two concurrent phenomena occur in the practical application of the process according to the invention, namely:
1. The required exchange of polyamines of aryl amine
2. Extraction of the amine salts by the organic phase.
The second of these two phenomena is undesirable because it is important in terms of process technology to obtain aqueous solutions of the aryl amine salts with maximum concentration. The higher this concentration, the smaller the amount of water which has to be removed by evaporation in order to obtain the necessary salt concentration for the initial condensation stage of the process.
In order to suppress extraction, it is necessary to use relatively small quantities of starting aryl amine in the exchange stage.
Unfortunately, this adversely affects the renlacement or exchange effect.
lt has been found that the process according to the invention may be carried out in different ways.
It has also been found that, in cases where relatively small quantities of aryl amine are used, it is necessary to use correspondingly lower concentrations of acid in the polyaryl amine salt solutions. The solubility of the aryl amines increases with relatively high concentrations of acid. In cases where relatively large quantities of aryl amine are used, two-phase systems are again obtained.
In order to obtain the best possible exchange effect with a minimal quantity of aryl amine, it is best to use a multi-stage process in which the aryl amine is circulated in each stage in such a way that, only a part of the aryl amine which takes part in the exchange in one stage is conveyed into the next stage, whilst the rest is recycled to the same stage. If for example the volume ratio of the quantities of aqueous polyaryl amine salt solution to be treated and the exchange aryl amine is 1:5 and if, in each stage, the quantity of aryl amine recycled is 4 times the quantity of the aryl amine conveyed to the next stage, the overall ratio between the phases for the same input of aryl amine amounts in each stage to 1:1, which provides for a better exchange effect and also for better phase separation.
It is also possible to keep the ratios between the streams in the stages different because the exchange effects vary in different stages. Exchange is far quicker at the beginning than at the end. It may also be advisable to change the ratio of the quantity of aryl amine recycled to the quantity conveyed to the next stage from stage to stage.
The at least partial insolubility of the aryl amines in aqueous polyaryl amine salt solutions (prerequisite for exchange) may also be obtained by the addition of hydrophobic (water-insoluble) solvents (WIS). This procedure can only be applied to a limited extent. The presence of relatively large quantities of WIS adversely affects the exchange. It has been found that, although excessively large additions of WIS reduce extraction of the salts, they adversely affect the exchange effect of the polyamines.
It is this which represents the difference from the process according to DT-OS No.
2,238,920 in which the increase in the quantity of WIS prevents or stops the exchange. This also shows that the exchange presupposes the existence of two heterogeneous. phases, the organic phase having to consist predominantly of aryl amine. It is evident that the aryl amines must be soluble to a certain extent in aqueous polyamine salt solutions.
This means that the optimal quantities of the WIS have to be experimentally determined for the apparatus used, a compromise having to be found between both concurrent phenomena. A ratio by weight of hydrophobic solvent to aryl amine of from 0.01:10 to 0.5:1 is preferred.
Suitable WIS are any solvents which are immiscible with water and inert with respect to the reaction products. Particularly suitable WIS are benzene and alkyl benzenes, chlorinated hydrocarbons and aliphatic and aromatic hydrocarbons. It is of considerable advantage to use WIS which boil at temperatures in the same range as the starting aryl amines, for example, aniline. They are then distilled together with excess amine and recirculated.
The solubility of aryl amines in water and in acid salt solutions is governed to a large extent by the salt concentration.
According to Landolt-Bornstein II, Vol.
2, Section C: Losungsgleichgewichte (solution equilibriums) II, page 601, the equilibria between aniline and aqueous solutions of the aniline hydrochloride are known. The solubility of the aniline increases to the miscibility stage with the concentration of aniline hydrochloride. For an aniline hydrochloride concentration of approximately 20%, both phases contain approximately 20 ,4 of salt.
If the quantity of salt in the aqueous phase is reduced to approximately 60/, the quantity of salt in the aniline phase decreases to around 1.4%.
The process may be adapted to these facts by working with different concentrations of salts in the countercurrent installation; with maximum possible salt concentrations on the aqueous phase side and with minimum possible salt concentrations on the organic phase side.
This result may be achieved by contacting the polyaryl amine salt solution with the aryl amine in several mixing stages, rather than one mixing stage, in such a way that the highest salt concentration is encountered at about the middle of the exchange installation.
It is also possible to introduce the aqueous polyaryl amine salt solution into about the middle stage of the multistage installation and to work with starting aryl amine and with water in countercurrent flow (as is standard practice for example in countercurrent extraction with water as the recycle component).
Another procedure is based on a combination of both processes: to begin with the PA/aqueous salt solution is treated with aryl amine/WIS, giving a 50 to 98 /" exchange, This is followed by treatment with pure aryl amine and completion of the exchange process.
In practice, this means that the WIS is added to the stream of aryl amine either in one stage or in several stages.
The exchange effect may also be enhanced for example by dividing the quantity of aryl amine into two or more streams, introducing these streams into the exchange stages and then combining them in countercurrent. The use of an inner circuit is particularly important in cases where the quantities of aryl amine are small.
The organic phase thus obtained should contain no more than 30 ppm of acid. This value may readily be obtained by washing with water, for example in a countercurrent extraction installation. The washing water may be used in the exchange installation.
The aqueous phase still contains dissolved starting aryl amine. The dissolved starting aryl amine may be removed either azeotropically be stripping (optionally with steam) or by extraction with hydrophobic solvents. The aqueous phase is then concentrated and introduced into the condensation stage.
The process according to the invention may be carried out with any aromatic amines such as, for example, aniline, o- toluidine, m-toluidine, N-methyl aniline, Nethyl aniline, 2,6-dimethyl aniline, 2,6diethyl aniline, 2,6-diisopropyl aniline, 2,4diaminotoluene and any mixtures of these amines. Aniline is preferably used as the aryl amine in the process according to the invention.
Water-soluble acids with a pKa-value of less than 1.5 are particularly suitable for use in the process according to the invention.
Examples of such acids are hydrochloric acid, hydrobromic acid, sulphuric acid, trifluoromethane sulphonic acid, benzene sulphonic acid or phosphoric acid.
Preferred catalysts are hydrochloric acid, trifluoroacetic acid and methane sulphonic acid. The above-mentioned acids may also be used in admixture with their acid or neutral salts such as for example the corresponding ammonium salts or even the corresponding alkali metal salts. It is of course also possible to use the salts formed from the above-mentioned acids and from the aryl amine used as starting amine as sole catalysts at the very beginning of the process.
The acid condensation mixture may be prepared in known manner by mixing a mixture of aromatic amine and acid catalyst with formaldehyde or formaldehyde donors and heating the precondensates formed to elevated temperatures for rearrangement.
Conversely, it is also possible initially to react the aromatic amine with formaldehyde and then to add the catalyst.
In both cases, it does not matter whether the reaction is carried out in the presence or absence of water. In either case, the acid condensation mixture is suitable for use in the process according to the invention.
The quantity of water added is governed primarily by the molar ratio of aryl amine to acid. Water should be added in such a quantity that the solubility of the aryl amines is below a certain limit.
The concentration of salt in water is preferably adjusted to between 2 and 50% and, with particular preference, to between 5% and 30%.
The water of condensation, the water from the formaldehyde and also from the addition are preferably removed in a single stage or multistage evaporator under pressure, in the absence of pressure or in vacuo, optionally after removal of the dissolved aryl amine, and are recirculated.
The exchange may be carried out at room temperature or at a temperature above room temperature, preferably at a temperature from 150C to 1000C, more preferably 180 to 350C.
The process according to the invention is distinguised by the following advantages: salt-free effluent
no consumption of acid catalyst
elimination of the need for base
elimination of the need for the neutralisation apparatus
economic advantages.
The exchange process may be carried out in various apparatus either continuously or in batches. It is preferred to use mixersettlers and countercurrent apparatus.
The density of the phases is influenced by several factors, namely salt concentration in water and in aryl amine and the content of polyaryl amine in aryl amine. The density of the phases is also governed by the catalyst.
For example, the polyamine (aniline) methane sulphonic acid salts in water are lighter than the mixtures of aniline and polyaryl amines.
With a 5% polyamine content, the aqueous soultions of the aniline methane
sulphonate are in turn heavier than aniline.
Phase reversal occurs. This phenomenon is unfavourable in terms of process technology.
Phase reversal may be avoided either by adding WIS or by using acid mixtures as catalysts.
The quantity of aryl amines required for exchange is determined by the composition of the salts (polyamine content), the type of apparatus used and the procedure adopted.
In cases where countercurrent installations are used, relatively small quantities are sufficient.
In general, the ratio by volume of the aryl amines to aqueous salt solution may amout to between 5:1 and 1:10 and preferably to between 1:1 and 1:5.
The process may also be used for the production of two products differing from one another in their composition.
In cases where the molar ratio of aryl
amine to acids is from 1:0.01 to 0.75, an organic layer separates following the addition of water. Experience has shown that this organic layer has a higher content
of 2,2/2,4, polyamines and trinuclear and higher nuclear polyamines than the polyamines obtained from salt solutions by aryl amines.
It is possible in this way to certain qualities from the outset.
The water may be added in any way: after condensation by straightforward mixing first for washing the polyamine and then for dilution, or some for washing and the rest for dilution. It may also be injected into different stages in several streams.
In order that the invention may be more fully understood, the following Examples are given, by way of illustration only: EXAMPLE 1
186 g of aniline (2 moles) are introduced into a stirrer-equipped vessel, followed by the addition of 171g of aqueous HCI (containing 1.5 mole of HCI). The contents of the vessel are then cooled to 250C. After the formaldehyde has been added, the contents of the vessel are stirred for I hour at 25"C and then heated to 90"C. The rearrangement time is 4 hours. The contents of the reaction vessel are then diluted and cooled by the addition of 500 cc of cold water. A homogeneous aqueous solution containing approximately 20% of salt is obtained.
600 g of the above solution are mixed 4 times at 250C with 250 g of aniline, followed by separation. The aqueous phase obtained after the fourth exchange is neutralised with alkali to pH 8, the amine liberated is taken up in chloroform and washed twice with water. The sample is then analysed by thin layer chromatography (TLC) on silica gel with chloroform-methanol (95:5% by weight) as eluant.
The free amine from the aqueous phase is found to consist almost completely of aniline. More than 99% of the polyamine has been exchanged for aniline.
EXAMPLE 2
93 g of aniline, 68.6 g of 70% aqueous methane sulphonic acid and 57.4 g of water are stirred and reacted in a vessel equipped with a stirrer. The temperature of the solution is adjusted to 50"C, followed by the dropwise addition over a period of 20 minutes of 73 g of 18.5% formaldehyde.
The ratio of aniline/formaldehyde/methane sulphonic acid is 1:0.45:0.5.
The total water content is approximately 50%.
Thereafter the contents of the vessel are kept for 1 hour at 500C and then for 2 hours at 700C and finally for 1 hour at 900 C.
On completion of the rearrangement, 295 cc of cold water are introduced and the temperature of the solution adjusted to 230C.
This solution is treated 4 times with 200 g of aniline in the same way as in Example 1.
Thin layer chromatography shows that the aqueous solution essentially contains only anilinemeihane sulphonate.
EXAMPLE 3
The condensation product of Example 2 is adjusted with water to a methane sulphonic acid content of 11%. Thereafter 100 g batches of the solution are mixed 5 times at room temperature, followed by separation, with:
a) 30 g of aniline
b) 30 g of aniline+7.5 g of monochlorobenzene
c) 30 g of aniline+ 15 g of monochlorobenzene
d) 30 g of aniline+30 g of monochlorobenzene
After each treatment, a sample of the aqueous phase is neutralised and subjected to thin layer chromatography.
It was found that, in test a), more than 99% of the polyamines were exchanged after only three treatments.
In test b) 98% after 4 treatments
In test c) approximately 80% after 5 treatments
In test d) approximately 50% after 5 treatments.
EXAMPLE 4
The condensation product of Example 2
is adjusted with water to a methane
sulphonic acid content of 15%. This
composition is miscible with aniline. Two
phases are formed by the addition of WIS.
3100 g batches of the solution are treated
5 times at room temperature with one of the
following mixtures:
a) 30 g of aniline +7.5 g of
monochlorobenzene
b) 30 g of aniline +30 g of
monochlorobenzene
c) 30 g of aniline +30 cc of toluene.
It was found by thin layer
chromatography that the exchange level is
a) at about 98% after 5 treatments
b) at 50% after 5 treatments
c) at 50% after 5 treatments.
EXAMPLE 5
This Example refers to Figure 1 of the
accompanying drawings which is a
diagrammatic representation of an
arrangement for carrying out the process of
the invention
In this drawing and in Figures 2 and 3 the
lines for the flow of material are represented
by U,U4. There are four mixers
represented by M1-M4 and four settlers
represented by S1S4.
A four-stage countercurrent mixer-settler
installation corresponding to Figure 1 is
operated as follows:
650 parts/hour of aqueous solution
consisting of
14.7% of polyamine (methylene dianiline
and high PA)
5.6% of hydrochloric acid (100%)
79.7% of water
are introduced into the mixer 1 through pipe
1.
100 parts/h of aniline are pumped through
pipe 2. The aniline phase is pump-circulated
at 650 parts per hour in each mixer-settler
stage. An aqueous solution containing 14%
of aniline hydrochloride and substantially
free from PA is obtained through pipe 4.
Polyamine/aniline mixture is obtained
through pipe 3.
EXAMPLE 5a The procedure is the same as in Example
5, the following streams being used:
650 parts/h of an aqueous solution
consisting of 16% of polyamine
(MDA+PA), 15% of methane sulphonic acid and 69% of water, and 150 parts/h of an organic solution consisting of 120 parts of aniline and 30 parts of o-dichlorobenzene.
The aqueous solution from pipe 4 contains 22% of a methane sulphonic acid/aniline/MDA-salt. Amine obtained by neutralisation consists of 98% of aniline and 2% of MDA.
EXAMPLE Sb
The arrangement used is that shown in
Figure 2. The procedure is as in Example 5, 90 parts/h of aniline being introduced through pipe 2 and 60 parts/h of a solution
consisting of 30 parts of aniline and 30 parts of o-dichlorobenzene through pipe 2a. The salt contained in the aqueous solution obtained through pipe 4 consists almost entirely of pure aniline methane sulphonate.
Polyamine/aniline mixture is obtained through pipe 3.
EXAMPLE Sc The arrangement used is that shown in
Figure 3. The procedure is as in Example 5,
except that 50 parts/h of aniline are
introduced through each of the pipes 2 and
2a.
The organic phases of stages S3 - and S4 are introduced together into the mixer
M2 through corresponding pipes.
An aqueous solution containing 16% of
aniline hydrochloride is obtained through
pipe 4. The salt is substantially free from
MDA.
EXAMPLE 6
An exchange installation of the type shown
in Figure 4 of the accompanying drawings
with 6 exchange stages (5-10) (mixer
settler) is operated as follows:
The water used for washing the
polyamine/aniline arrives through pipe 12.
The condensation solution containing HCI
is introduced through the pipes 11 a, b, c in
such a way that the concentration of HC1 is
adjusted as follows:
in stage 5:1.5%
in stage 6:3.5%
in stage 7:5.6%.
Aniline arrives through pipe 15a, b, c, the
sum of the stream being equal to 25% by
volume of the total sum of 12+11a, b, c.
An aniline/polyamine stream 14
containing approximately 0.5% of HCI and
an aqueous solution 13 of the aniline
hydrochloride containing approximately
19% of salt and 5.6% of aniline are
obtained.
The post-extraction stage gives an aniline
hydrochloride solution with a concentration
of approximately 25% which is concentrated
by evaporation.
The aniline/polyamine stream is washed
with water in a countercurrent extraction installation and worked up in accordance with the prior art.
WHAT I CLAIM IS:
1. A process for the production of polyarylamines containing methylene bridges, in which a methylene-bridged polyarylamine salt solution, produced by the condensation of arylamines and formaldehyde in the presence of acids and water, is exchanged with a further quantity of arylamine starting material, by mixing the polyarylamine salt solution with the further quantity of arylamine starting material in one or more stages, to form a heterogeneous system, allowing the polyarylamine salt and the aryl amine to react together, then separating the aqueous phase and the organic phase and recycling the aqueous arylamine salt phase to the condensatin process.
2. A process as claimed in claim I in which water is added to the polyaryl amine salt solution.
3. A process as claimed in claim 1 or claim 2 in which hydrophobic solvents are present during mixing.
4. A process as claimed in claim 3 in which the ratio by weight of hydrophobic solvents to aryl amine is from 0.01:10 to 0.5:1.
5. A process as claimed in any of claims 1 to 4 in which the process is operated continuously.
6. A process as claimed in any of claims 1 to 4 in which the ratio by volume of organic phase to aqueous phase in each stage is from 20:1 to 1:10.
7. A process as claimed in any of claims 1 to 6 in which the exchange is carried out first with a mixture of aryl amine and hydrophobic solvent and then with pure aryl amine.
8. A process as claimed in any of claims 1 to 7 in which the ratio of aryl amine to hydrophobic solvent is different from stage to stage.
9. A process as claimed in any of claims 1 to 8 in which the exchange is carried out with a divided aryl amine stream, the component streams only being combined after two or more stages.
10. A process as claimed in any of claims
1 to 9 in which the concentration of the salt after dilution of the reacted condensation mixture is adjusted with aryl amine to between 2 and 50% before the exchange.
11. A process as claimed in claim 10, in which the concentration of the salt is diluted to 5 to 30% before the exchange.
12. A process as claimed in any of claims 1 to 11 in which the resulting solution of polyamine in aryl amine is washed with water and the washing water is used for diluting the condensation mixture.
13. A process as claimed in any of claims
1 to 12 in which aniline, o-toluidine, Nmethyl aniline, N-ethyl aniline or mixtures thereof are used as aromatic amines.
14. A process as claimed in any of claims
1 to 13 in which methane sulphonic acid, trifluoroacetic acid, hydrochloric acid or mixtures thereof are used as the acid catalyst.
15. A process as claimed in any of claims 1 to 14 in which the molar ratio of aromatic amines to formaldehyde is in the range of 10:1 and 1:1.
16. A process as claimed in any of claims 1 to 15 in which the molar ratio of aromatic amine to acid catalyst is in the range of 20:1 and 1:1.
17. A process as claimed in any of claims 1 to 16 in which the exchange is carried out at a temperature of from 15 to 1000C.
18. A process as claimed in claim 17 in which the temperature employed is within the range of 18 to 350C.
19. A process as claimed in any of claims
I to 18 in which the polyamine product solution is introduced at approximately the middle exchange stage.
20. A process as claimed in any of claims 1 to 19, in which the concentration of salt is kept at the maximum possible concentration in the aqueous phase and the minimum possible concentration in the organic phase.
21. A process as claimed in claim 1 substantially as herein described with reference to any one of the Examples.
22. Polyaryl amines containing methylene bridges when made by the process claimed in any of claims 1 to 21.
**WARNING** end of DESC field may overlap start of CLMS **.
Claims (22)
1. A process for the production of polyarylamines containing methylene bridges, in which a methylene-bridged polyarylamine salt solution, produced by the condensation of arylamines and formaldehyde in the presence of acids and water, is exchanged with a further quantity of arylamine starting material, by mixing the polyarylamine salt solution with the further quantity of arylamine starting material in one or more stages, to form a heterogeneous system, allowing the polyarylamine salt and the aryl amine to react together, then separating the aqueous phase and the organic phase and recycling the aqueous arylamine salt phase to the condensatin process.
2. A process as claimed in claim I in which water is added to the polyaryl amine salt solution.
3. A process as claimed in claim 1 or claim 2 in which hydrophobic solvents are present during mixing.
4. A process as claimed in claim 3 in which the ratio by weight of hydrophobic solvents to aryl amine is from 0.01:10 to 0.5:1.
5. A process as claimed in any of claims 1 to 4 in which the process is operated continuously.
6. A process as claimed in any of claims 1 to 4 in which the ratio by volume of organic phase to aqueous phase in each stage is from 20:1 to 1:10.
7. A process as claimed in any of claims 1 to 6 in which the exchange is carried out first with a mixture of aryl amine and hydrophobic solvent and then with pure aryl amine.
8. A process as claimed in any of claims 1 to 7 in which the ratio of aryl amine to hydrophobic solvent is different from stage to stage.
9. A process as claimed in any of claims 1 to 8 in which the exchange is carried out with a divided aryl amine stream, the component streams only being combined after two or more stages.
10. A process as claimed in any of claims
1 to 9 in which the concentration of the salt after dilution of the reacted condensation mixture is adjusted with aryl amine to between 2 and 50% before the exchange.
11. A process as claimed in claim 10, in which the concentration of the salt is diluted to 5 to 30% before the exchange.
12. A process as claimed in any of claims 1 to 11 in which the resulting solution of polyamine in aryl amine is washed with water and the washing water is used for diluting the condensation mixture.
13. A process as claimed in any of claims
1 to 12 in which aniline, o-toluidine, Nmethyl aniline, N-ethyl aniline or mixtures thereof are used as aromatic amines.
14. A process as claimed in any of claims
1 to 13 in which methane sulphonic acid, trifluoroacetic acid, hydrochloric acid or mixtures thereof are used as the acid catalyst.
15. A process as claimed in any of claims 1 to 14 in which the molar ratio of aromatic amines to formaldehyde is in the range of 10:1 and 1:1.
16. A process as claimed in any of claims 1 to 15 in which the molar ratio of aromatic amine to acid catalyst is in the range of 20:1 and 1:1.
17. A process as claimed in any of claims 1 to 16 in which the exchange is carried out at a temperature of from 15 to 1000C.
18. A process as claimed in claim 17 in which the temperature employed is within the range of 18 to 350C.
19. A process as claimed in any of claims
I to 18 in which the polyamine product solution is introduced at approximately the middle exchange stage.
20. A process as claimed in any of claims 1 to 19, in which the concentration of salt is kept at the maximum possible concentration in the aqueous phase and the minimum possible concentration in the organic phase.
21. A process as claimed in claim 1 substantially as herein described with reference to any one of the Examples.
22. Polyaryl amines containing methylene bridges when made by the process claimed in any of claims 1 to 21.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH1461875 | 1975-11-11 | ||
CH585476 | 1976-05-05 | ||
CH1004976 | 1976-08-04 |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1567638A true GB1567638A (en) | 1980-05-21 |
Family
ID=27175350
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB46742/76A Expired GB1567638A (en) | 1975-11-11 | 1976-11-10 | Process the production of polyaryl amines containing methylene bridges |
Country Status (22)
Country | Link |
---|---|
JP (1) | JPS5260895A (en) |
AT (1) | ATA836676A (en) |
BR (1) | BR7607527A (en) |
CA (1) | CA1087633A (en) |
DD (1) | DD128184A5 (en) |
DE (1) | DE2648982C2 (en) |
DK (1) | DK508476A (en) |
ES (1) | ES453159A1 (en) |
FR (1) | FR2331575A1 (en) |
GB (1) | GB1567638A (en) |
GR (1) | GR60355B (en) |
IE (1) | IE44544B1 (en) |
IL (1) | IL50857A (en) |
LU (1) | LU76153A1 (en) |
MX (1) | MX148753A (en) |
NL (1) | NL7612539A (en) |
PL (1) | PL104368B1 (en) |
PT (1) | PT65803B (en) |
RO (1) | RO79103A (en) |
SE (1) | SE421533B (en) |
TR (1) | TR19975A (en) |
YU (1) | YU271776A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8557949B2 (en) | 2007-09-19 | 2013-10-15 | Huntsman International Llc | Process for production of di- and polyamines of the diphenylmethane series |
US9217054B2 (en) | 2007-09-19 | 2015-12-22 | Huntsman International Llc | Process for production of di- and polyamines of the diphenylmethane series |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0009094B1 (en) * | 1978-09-12 | 1982-04-14 | GebràDer Sulzer Aktiengesellschaft | Process for the preparation of methylene-bridge polyaryl amines |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3367969A (en) * | 1965-03-08 | 1968-02-06 | Du Pont | Process for the preparation of 4, 4'-methylenedianiline |
GB1287141A (en) * | 1969-01-01 | 1972-08-31 | Ici Ltd | Manufacture of methylene-bridged polyarylamines |
DE2227110C3 (en) * | 1972-06-03 | 1984-08-23 | Bayer Ag, 5090 Leverkusen | Process for the production of polyamines |
DE2238920C3 (en) * | 1972-08-08 | 1984-09-27 | Bayer Ag, 5090 Leverkusen | Process for the production of polyamines |
DE2238378C3 (en) * | 1972-08-04 | 1975-01-09 | Farbwerke Hoechst Ag, Vormals Meister Lucius & Bruening, 6000 Frankfurt | Perlnon dyes and their method of manufacture |
DE2343658C2 (en) * | 1973-08-30 | 1982-06-03 | Bayer Ag, 5090 Leverkusen | Process for the production of polyamines |
DE2356828C2 (en) * | 1973-11-14 | 1982-10-21 | Bayer Ag, 5090 Leverkusen | Process for the production of polyamines and their use as starting material for the production of polyisocyanates |
DE2500573A1 (en) * | 1975-01-09 | 1976-07-15 | Bayer Ag | PROCESS FOR PRODUCING POLYAMINES |
-
1976
- 1976-10-28 DE DE2648982A patent/DE2648982C2/en not_active Expired
- 1976-10-29 IE IE2421/76A patent/IE44544B1/en unknown
- 1976-11-05 IL IL50857A patent/IL50857A/en unknown
- 1976-11-05 YU YU02717/76A patent/YU271776A/en unknown
- 1976-11-05 PT PT65803A patent/PT65803B/en unknown
- 1976-11-05 CA CA264,973A patent/CA1087633A/en not_active Expired
- 1976-11-06 RO RO7688358A patent/RO79103A/en unknown
- 1976-11-06 GR GR52122A patent/GR60355B/en unknown
- 1976-11-09 DD DD7600195684A patent/DD128184A5/en unknown
- 1976-11-09 LU LU76153A patent/LU76153A1/xx unknown
- 1976-11-09 PL PL1976193576A patent/PL104368B1/en unknown
- 1976-11-09 SE SE7612478A patent/SE421533B/en unknown
- 1976-11-10 BR BR7607527A patent/BR7607527A/en unknown
- 1976-11-10 MX MX166949A patent/MX148753A/en unknown
- 1976-11-10 FR FR7634029A patent/FR2331575A1/en active Granted
- 1976-11-10 GB GB46742/76A patent/GB1567638A/en not_active Expired
- 1976-11-10 TR TR19975A patent/TR19975A/en unknown
- 1976-11-10 ES ES453159A patent/ES453159A1/en not_active Expired
- 1976-11-11 AT AT0836676A patent/ATA836676A/en not_active Application Discontinuation
- 1976-11-11 DK DK508476A patent/DK508476A/en not_active Application Discontinuation
- 1976-11-11 JP JP51136170A patent/JPS5260895A/en active Pending
- 1976-11-11 NL NL7612539A patent/NL7612539A/en not_active Application Discontinuation
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8557949B2 (en) | 2007-09-19 | 2013-10-15 | Huntsman International Llc | Process for production of di- and polyamines of the diphenylmethane series |
US9217054B2 (en) | 2007-09-19 | 2015-12-22 | Huntsman International Llc | Process for production of di- and polyamines of the diphenylmethane series |
Also Published As
Publication number | Publication date |
---|---|
IE44544B1 (en) | 1981-12-30 |
DK508476A (en) | 1977-05-12 |
ATA836676A (en) | 1982-08-15 |
PL104368B1 (en) | 1979-08-31 |
NL7612539A (en) | 1977-05-13 |
GR60355B (en) | 1978-05-18 |
PT65803B (en) | 1978-05-12 |
BR7607527A (en) | 1977-09-20 |
DD128184A5 (en) | 1977-11-02 |
JPS5260895A (en) | 1977-05-19 |
DE2648982C2 (en) | 1985-07-11 |
IL50857A0 (en) | 1977-01-31 |
LU76153A1 (en) | 1977-05-18 |
SE421533B (en) | 1982-01-04 |
SE7612478L (en) | 1977-05-12 |
ES453159A1 (en) | 1978-03-01 |
FR2331575B1 (en) | 1980-05-09 |
MX148753A (en) | 1983-06-14 |
TR19975A (en) | 1980-06-02 |
IL50857A (en) | 1981-05-20 |
CA1087633A (en) | 1980-10-14 |
DE2648982A1 (en) | 1977-05-26 |
RO79103A (en) | 1982-06-25 |
FR2331575A1 (en) | 1977-06-10 |
YU271776A (en) | 1982-05-31 |
PT65803A (en) | 1976-12-01 |
IE44544L (en) | 1977-05-11 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed [section 19, patents act 1949] | ||
PCNP | Patent ceased through non-payment of renewal fee |