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 n11 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.

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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 n11 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.

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The invention relates to a process for preparing a semi-aromatic polyamide from diamine and dicarboxylic acid, comprising steps of •(i) dosing a liquid diamine to an agitated powder comprising an aromatic dicarboxylic acid thereby forming a powder comprising a diamine/dicarboxylic acid salt (DD-salt), and •(ii) solid-state polymerizing the DD-salt to obtain the polyamide.

The invention relates to a process for preparing a semi-aromatic polyamide from diamine and dicarboxylic acid, comprising steps of •(i) dosing a liquid diamine to an agitated powder comprising an aromatic dicarboxylic acid thereby forming a powder comprising a diamine/dicarboxylic acid salt (DD-salt), and •(ii) solid-state polymerizing the DD-salt to obtain the polyamide.

A method of removing carbon dioxide from a carbonate-containing diaminoalkane solution, the method including passing the carbonate-containing diaminoalkane solution through a membrane module, and a method of preparing diaminoalkane including the same.

A method of removing carbon dioxide from a carbonate-containing diaminoalkane solution, the method including passing the carbonate-containing diaminoalkane solution through a membrane module, and a method of preparing diaminoalkane including the same.

The present invention relates to a process for purifying adiponitrile (ADN), wherein crude ADN is introduced into a rectification apparatus (R1). The rectification apparatus (R1) comprises a first side draw and preferably also a second side draw, the first side draw being disposed below the crude ADN introduction point and the optional second side draw being disposed above the crude ADN introduction point. The first side draw is used to draw off a gaseous stream comprising ADN while the optional second side draw is used to draw off undesired by-products such as 1-amino-2-cyanocyclopentene (ACCP) which are often generated in ADN production and consequently may be present in the crude ADN. The gaseous stream from the first side draw of (R1) is introduced into a second rectification apparatus (R2). (R2) is used to separate off ADN from remaining high boilers and any other by-products present, pure ADN being drawn off from (D2) as overhead product. It is preferable when the process according to the invention employs crude ADN from a reaction of butadiene with hydrocyanic acid (HCN).

The present invention relates to a process for purifying adiponitrile (ADN), wherein crude ADN is introduced into a rectification apparatus (R1). The rectification apparatus (R1) comprises a first side draw and preferably also a second side draw, the first side draw being disposed below the crude ADN introduction point and the optional second side draw being disposed above the crude ADN introduction point. The first side draw is used to draw off a gaseous stream comprising ADN while the optional second side draw is used to draw off undesired by-products such as 1-amino-2-cyanocyclopentene (ACCP) which are often generated in ADN production and consequently may be present in the crude ADN. The gaseous stream from the first side draw of (R1) is introduced into a second rectification apparatus (R2). (R2) is used to separate off ADN from remaining high boilers and any other by-products present, pure ADN being drawn off from (D2) as overhead product. It is preferable when the process according to the invention employs crude ADN from a reaction of butadiene with hydrocyanic acid (HCN).

The invention relates to a process for preparing primary amines, which comprises hydrogenating at least one nitrile in an apparatus (V1) in the presence of an unsupported cobalt catalyst to obtain at least one primary amine, with recurrent or continuous addition of at least one compound (I) to the apparatus (V1), said compound (I) comprising at least one component selected from alkali metal, alkaline earth metal and rare earth metal.

The invention relates to a process for preparing primary amines, which comprises hydrogenating at least one nitrile in an apparatus (V1) in the presence of an unsupported cobalt catalyst to obtain at least one primary amine, with recurrent or continuous addition of at least one compound (I) to the apparatus (V1), said compound (I) comprising at least one component selected from alkali metal, alkaline earth metal and rare earth metal.