Abstract:
PROBLEM TO BE SOLVED: To provide a method for producing hexanediol-1,6 from a carboxylic acid mixture. SOLUTION: In the method, (a) the carboxylic acids contained in an aqueous dicarboxylic acid mixture are converted to the corresponding carboxylic acid esters by using a low-molecular weight alcohol, (b) the obtained esterification mixture is separated from the excess alcohol and low-boiling point components in a first distillation stage, (c) the bottom products are fractionated in a second distillation stage into an ester fraction essentially free of 1,4-cyclohexanediol and a fraction comprising at least the major part of the 1,4-cyclohexanediol, (d) the ester fraction substantially free of 1,4-cyclohexanediol is catalytically hydrogenated, and (e) 1,6-hexanediol is obtained in a rectification stage from the hydrogenated discharge in a known manner. Thereby, high purity 1,6-hexanediol is made obtainable from waste products in a high yield. COPYRIGHT: (C)2009,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To provide a method for preparing 1,6-hexanediol from a carboxylic acid mixture.SOLUTION: The method for preparing 1,6-hexanediol includes processes of: (a) converting carboxylic acids contained in an aqueous dicarboxylic acid mixture to the corresponding carboxylic acid esters by using a low-molecular weight alcohol; (b) separating the obtained esterification mixture from excessive alcohol and low-boiling point components in a first distillation stage; (c) fractionating bottom products in a second distillation stage into an ester fraction essentially free of 1,4-cyclohexanediol and a fraction comprising the major part of 1,4-cyclohexanediol; (d) catalytically hydrogenating the ester fraction essentially free of 1,4-cyclohexanediol; and (e) obtaining 1,6-hexanediol in a purifying distillation stage from the hydrogenation product in a known manner. In this way, high purity 1,6-hexanediol can be obtained in a high yield from waste products.
Abstract:
Procedimiento para la obtención de una cetona cíclica con 7 a 16 átomos de carbono, que comprende al menos las etapas: (a) oxidación de una composición (I), que contiene al menos un alqueno cíclico con 7 a 16 átomos de carbono con al menos dos dobles enlaces C-C, por medio de monóxido de dinitrógeno, bajo obtención de una composición (A), (b) tratamiento de la composición (A) con al menos una base, bajo obtención de una composición (B), (c) hidrogenado de la composición (B) en presencia de al menos un catalizador, bajo obtención de una composición (C), (d) purificación de la composición (C), que comprende al menos los pasos: (di) tratamiento térmico de la composición (C) con al menos un ácido, o al menos un catalizador, que contiene al menos un metal de transición, (dii) purificación adicional mediante un procedimiento seleccionado a partir del grupo constituido por destilación, extracción y cristalización.
Abstract:
The invention relates to a process for purifying an ionic liquid, which comprises the steps (a) partial crystallization of the ionic liquid from its melt and (b) separation of the crystals from the residual melt.
Abstract:
Procedimiento para la purificación por destilación de dimetilacetamida en bruto, que contiene agua (DMAc en bruto), que contiene DMAc, productos de bajo puntos de ebullición y productos de elevado punto de ebullición, separándose los productos de bajo punto de ebullición y los productos de elevado punto de ebullición con obtención de DMAc pura en una columna o en una o varias columnas conectada en serie, caracterizado porque se retira la DMAc pura como corriente lateral líquida (4) a partir de una columna o a partir de la última columna de un conjunto de columnas.
Abstract:
The present invention relates to a process for purifying a composition (I) at least comprising cyclododecanone. The process according to the invention for purifying a composition (I) at least comprising cyclododecanone comprises at least step (i) (i) irradiation of the composition (I).
Abstract:
Disclosed is a method for the distillative purification of aqueous raw dimethylacetamide (raw DMAc) containing DMAc as well as low-boiling and high-boiling components. According to the inventive method, the low-boiling and high-boiling components are eliminated in one column or several columns that are mounted in series so as to obtain pure DMAc. The disclosed method is characterized in that the pure DMAc is withdrawn from the single column or the last of several columns as a liquid side stream.
Abstract:
Procedimiento para la obtención de ciclododecanona, que comprende al menos los pasos (a) obtención de una composición (I') que contiene al menos ciclododecanona, que comprende al menos las etapas (a-1) trimerización de butadieno para dar ciclododecatrieno, (a-2) oxidación de ciclododecatrieno para dar ciclododecadienona, (a-3) hidrogenado de ciclododecadienona para dar ciclododecanona, (b) purificación de la composición (I'), que comprende al menos las etapas (i) tratamiento térmico de la composición (I') con al menos un catalizador heterogéneo, aplicado sobre un soporte, que contiene al menos un metal de transición del 8º grupo secundario del sistema periódico de los elementos, (ii) purificación subsiguiente mediante un procedimiento seleccionado a partir del grupo constituido por destilación, extracción y cristalización, no efectuándose entre las etapas (a-2) y (a-3) un tratamiento de la composición obtenida en la etapa (a-2) con al menos una base.
Abstract:
The invention relates to a process for purifying an ionic liquid, which comprises the steps (a) partial crystallization of the ionic liquid from its melt and (b) separation of the crystals from the residual melt.
Abstract:
Disclosed is a method for the distillative purification of aqueous raw dimethylacetamide (raw DMAc) containing DMAc as well as low-boiling and high-boiling components. According to the inventive method, the low-boiling and high-boiling components are eliminated in one column or several columns that are mounted in series so as to obtain pure DMAc. The disclosed method is characterized in that the pure DMAc is withdrawn from the single column or the last of several columns as a liquid side stream.