Process for the production of di- and polyamines of the diphenylmethane series

US10538480B2 · US · B2

Patent metadata
FieldValue
Publication numberUS-10538480-B2
Application numberUS-201715632501-A
CountryUS
Kind codeB2
Filing dateJun 26, 2017
Priority dateJun 30, 2016
Publication dateJan 21, 2020
Grant dateJan 21, 2020

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  1. Title

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  2. Abstract

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  3. Assignees and inventors

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  4. Key dates

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  5. First independent claim

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  6. CPC / IPC classifications

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Abstract

Official abstract text for this publication.

The invention relates to a production process for di- and polyamines of the diphenylmethane series by the rearrangement of a condensation product of aniline and a methylene group-supplying agent preferably selected from the group consisting of aqueous formaldehyde solution, gaseous formaldehyde, para-formaldehyde, trioxane and mixtures thereof, wherein said condensation product is reacted in the presence of at least one silica-alumina catalyst, said catalyst having a surface area as determined by the BET method carried out according to ASTM D3663-03 (2015) of from 200 m 2 /g to 520 m 2 /g, preferably of from 350 m 2 /g to 495 m 2 /g, particularly preferably of from 400 m 2 /g to 490 m 2 /g, a molar ratio of silica/alumina on the catalyst surface of A, an overall (bulk) molar ratio of silica/alumina of C, and a quotient B=A/C; said catalyst being characterised in that “low” A values (i.e. equal to or lower than 8.0) are combined with “high” B values (i.e. of from 1.50 to 3.00), and “high” A values (i.e. larger than 8.00, especially equal to or larger than 8.50) are combined with “low” B values (i.e. of from 0.15 to 1.40).

First claim

Opening claim text (preview).

The invention claimed is: 1. A process for the preparation of di- and polyamines of the diphenylmethane series comprising rearranging a condensation product of aniline and a methylene group-supplying agent, wherein said condensation product is reacted in the presence of at least one silica-alumina catalyst, wherein said catalyst has (i) a surface area as determined by the BET method carried out according to ASTM D3663-03 (2015) of from 200 m 2 /g to 520 m 2 /g; (ii) a molar ratio of silica/alumina as determined by X-ray photoelectron spectroscopy of A; and (iii) a quotient B equal to (the molar ratio of silica/alumina as determined by X-ray photoelectron spectroscopy) divided by (the molar ratio of silica/alumina as determined by inductively coupled plasma optical emission spectroscopy); in which A and B of the catalyst meet one of the following requirements: either (I) A is of from 0.10 to 8.00 and B is of from 1.50 to 3.00, or (II) A is >8.00 and B is of from 0.15 to 1.40. 2. The process according to claim 1 , wherein said at least one silica-alumina catalyst is prepared by co-precipitating a water-soluble aluminium precursor and a water-soluble silicon precursor. 3. The process according to claim 2 , wherein said water-soluble aluminium precursor comprises an alkali metal aluminium salt and the water-soluble silicon precursor comprises an alkali metal silicon salt. 4. The process according to claim 2 , wherein the co-precipitation is carried out in the presence of a precipitating agent which is selected from the group consisting of mineral acids and carboxylic acids. 5. The process according to claim 1 , wherein said at least one silica-alumina catalyst has a core-shell structure. 6. The process according to claim 5 , wherein the core of said at least one silica-alumina catalyst comprises an aluminium species which is selected from the group consisting of aluminium oxides, aluminium oxide hydroxides and aluminium hydroxides. 7. The process according to claim 6 , wherein said at least one silica-alumina catalyst is prepared by precipitating a water-soluble silicon precursor onto the core. 8. The process according to claim 7 , wherein the precipitation is carried out in the presence of a precipitating agent which is selected from the group consisting of mineral acids and carboxylic acids. 9. The process according to claim 5 , wherein the core of said at least one silica-alumina catalyst comprises a silicon species which is selected from the group consisting of silica and mesoporous silica. 10. The process according to claim 9 , wherein said at least one silica-alumina catalyst is prepared by precipitating a water-soluble inorganic aluminium precursor onto the core. 11. The process according to claim 10 , wherein the precipitation is carried out in the presence of an alkaline precipitating agent. 12. The process according to claim 11 , wherein said alkaline precipitating agent comprises urea. 13. The process according to claim 9 , wherein said at least one silica-alumina catalyst is prepared by hydrolysing an organic aluminium precursor onto the core. 14. The process according to claim 13 , wherein said organic aluminium precursor is selected from the group consisting of aluminium isopropoxide, aluminium acetate and aluminium lactate. 15. The process according to claim 1 , wherein A and B of the catalyst meet the requirements of (I). 16. The process according to claim 1 , wherein A is of from 0.15 to 5.00 and B is of from 1.55 to 2.10. 17. The process according to claim 1 , wherein A is of from 0.65 to 4.50 and B is of from 1.65 to 2.00.

Assignees

Inventors

Classifications

  • with at least two amino groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton · CPC title

  • by rearrangement reactions · CPC title

  • C07C209/78Primary

    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 · CPC title

  • aromatic · CPC title

  • Silica · CPC title

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What does patent US10538480B2 cover?
The invention relates to a production process for di- and polyamines of the diphenylmethane series by the rearrangement of a condensation product of aniline and a methylene group-supplying agent preferably selected from the group consisting of aqueous formaldehyde solution, gaseous formaldehyde, para-formaldehyde, trioxane and mixtures thereof, wherein said condensation product is reacted in th…
Who is the assignee on this patent?
Covestro Deutschland Ag
What technology area does this patent fall under?
Primary CPC classification C07C209/78. Mapped technology areas include Chemistry & Metallurgy.
When was this patent published?
Publication date Tue Jan 21 2020 00:00:00 GMT+0000 (Coordinated Universal Time) (B2). Legal status and post-grant events are not shown on this page.
What related patents are in patentsdb?
We list 1 related publication on this page (citations in our corpus or others sharing the same primary CPC).