A method is provided for collecting a compound of formula (III) (in which R31 is a monovalent to trivalent organic group and n31 is an integer of 1 to 3) from a liquid phase component that is formed as a by-product in a method for producing a compound of general formula (I) (in which R11 is a monovalent to trivalent organic group and n 11 is an integer of 1 to 3), wherein the collection method contains steps (1) to (3) or steps (A) and (B), and step (4). Step (1): a step for reacting the liquid phase component with at least one active hydrogen-containing compound in a reactor. Step (2): a step for returning a condensed liquid obtained by cooling gas phase components in the reactor to the reactor. Step (3): a step for discharging gas phase components that are not condensed in the step (2) to the outside of the reactor. Step (A): a step for mixing the liquid phase component, water, and a compound of general formula (III). Step (B): a step for reacting the liquid phase component with water inside the reactor. Step (4): a step for discharging, as a liquid phase component inside the reactor, the reaction liquid containing the compound of general formula (III) to the outside of the reactor.
R.sup.11NCO).sub.n11  (I)
R.sup.31NH.sub.2).sub.n31  (III)

A method is provided for collecting a compound of formula (III) (in which R31 is a monovalent to trivalent organic group and n31 is an integer of 1 to 3) from a liquid phase component that is formed as a by-product in a method for producing a compound of general formula (I) (in which R11 is a monovalent to trivalent organic group and n 11 is an integer of 1 to 3), wherein the collection method contains steps (1) to (3) or steps (A) and (B), and step (4). Step (1): a step for reacting the liquid phase component with at least one active hydrogen-containing compound in a reactor. Step (2): a step for returning a condensed liquid obtained by cooling gas phase components in the reactor to the reactor. Step (3): a step for discharging gas phase components that are not condensed in the step (2) to the outside of the reactor. Step (A): a step for mixing the liquid phase component, water, and a compound of general formula (III). Step (B): a step for reacting the liquid phase component with water inside the reactor. Step (4): a step for discharging, as a liquid phase component inside the reactor, the reaction liquid containing the compound of general formula (III) to the outside of the reactor.
R.sup.11NCO).sub.n11  (I)
R.sup.31NH.sub.2).sub.n31  (III)

The present invention relates to a process for preparing di- and polyamines of the diphenyl methane series. More specifically, the process comprises reacting aniline and formaldehyde by (1a) mixing aniline with hydrochloric acid to form aniline hydrochloride, and (1b) mixing the aniline hydrochloride with a first portion of aqueous formaldehyde; or (1c) mixing aniline with a first portion of aqueous formaldehyde to form an aminal, and (1d) mixing the aminal with hydrochloric acid; to obtain a first reaction product; (2) converting the first reaction product to a second reaction product comprising di- and polyamines of the diphenyl methane series in a cascade of 4 to 25 reaction zones arranged in series, wherein a second portion of aqueous formaldehyde is added to the second of the reaction zones, in which second reaction zone the temperature is equal to or up to 20° C. higher than the temperature in the first reaction zone, and wherein the temperature consecutively increases from the third to the last of the reaction zones, the temperature in the third of the reaction zones being from 15° C. to 50° C. higher than in the second of the reaction zones, and (3) working-up the second reaction product to obtain the di- and polyamines of the diphenyl methane series.

The present invention relates to a process for preparing di- and polyamines of the diphenyl methane series. More specifically, the process comprises reacting aniline and formaldehyde by (1a) mixing aniline with hydrochloric acid to form aniline hydrochloride, and (1b) mixing the aniline hydrochloride with a first portion of aqueous formaldehyde; or (1c) mixing aniline with a first portion of aqueous formaldehyde to form an aminal, and (1d) mixing the aminal with hydrochloric acid; to obtain a first reaction product; (2) converting the first reaction product to a second reaction product comprising di- and polyamines of the diphenyl methane series in a cascade of 4 to 25 reaction zones arranged in series, wherein a second portion of aqueous formaldehyde is added to the second of the reaction zones, in which second reaction zone the temperature is equal to or up to 20° C. higher than the temperature in the first reaction zone, and wherein the temperature consecutively increases from the third to the last of the reaction zones, the temperature in the third of the reaction zones being from 15° C. to 50° C. higher than in the second of the reaction zones, and (3) working-up the second reaction product to obtain the di- and polyamines of the diphenyl methane series.

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.sup.2/g to 520 m.sup.2/g, preferably of from 350 m.sup.2/g to 495 m.sup.2/g, particularly preferably of from 400 m.sup.2/g to 490 m.sup.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).

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.sup.2/g to 520 m.sup.2/g, preferably of from 350 m.sup.2/g to 495 m.sup.2/g, particularly preferably of from 400 m.sup.2/g to 490 m.sup.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).

A supported catalyst having rhodium particles with an average diameter of less than 1 nm disposed on a support material containing magnetic iron oxide (e.g. Fe.sub.3O.sub.4). A method of producing the supported catalyst and a process of reducing nitroarenes to corresponding aromatic amines employing the supported catalyst with a high product yield are also described. The supported catalyst may be recovered with ease using an external magnet and reused.

The present invention relates to a catalytic material for the preparation of one or more of 4,4′-methylenedianiline, 2,2′-methylenedianiline, 2,4′-methylenedianiline, and oligomers of two or more thereof, the catalytic material comprising an oxidic support, wherein the oxidic support comprises an element E.sub.OS1 selected from the group consisting of Ti, Zr, Al, Si, and mixtures of two or more thereof, and further comprising a supported material supported on the oxidic support, wherein the supported material comprises an element E.sub.SM1 selected from the group consisting of Ti, Zr, V, Nb, Ta, Mo, W, Ge, Sn, Sc, Y, La, Ce, Nd, Pr, Hf, Cr, Fe, Co, Ni, Cu Zn, Pb and mixtures of two or more thereof. Further, the present invention relates in particular to a process for the preparation of a catalytic material and to a process for the preparation of one or more of 4,4′-methylenedianiline, 2,2′-methylenedianiline, 2,4′-methylenedianiline and oligomers of two or more thereof.

The present invention relates to a catalytic material for the preparation of one or more of 4,4′-methylenedianiline, 2,2′-methylenedianiline, 2,4′-methylenedianiline, and oligomers of two or more thereof, the catalytic material comprising an oxidic support, wherein the oxidic support comprises an element E.sub.OS1 selected from the group consisting of Ti, Zr, Al, Si, and mixtures of two or more thereof, and further comprising a supported material supported on the oxidic support, wherein the supported material comprises an element E.sub.SM1 selected from the group consisting of Ti, Zr, V, Nb, Ta, Mo, W, Ge, Sn, Sc, Y, La, Ce, Nd, Pr, Hf, Cr, Fe, Co, Ni, Cu Zn, Pb and mixtures of two or more thereof. Further, the present invention relates in particular to a process for the preparation of a catalytic material and to a process for the preparation of one or more of 4,4′-methylenedianiline, 2,2′-methylenedianiline, 2,4′-methylenedianiline and oligomers of two or more thereof.

A light-absorbing material includes a compound represented by the formula (1) below. In the formula (1), L.sup.1 to L.sup.3 are each independently represented by the formula (2) or (3) below:

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