摘要:
The invention provides a process for producing dialkanolamines through amination of alkylene oxide with ammonia at liquid phase, in which side formation of trialkanolamines is inhibited and dialkanolamines can be produced with high selectivity and high efficiency. Said process is carried out in the presence of a catalyst which possesses such reaction characteristics that render the rate constant &agr; of the reaction between ammonia and alkylene oxide not less than 0.10, when the reaction rate constant between monoalkanolamine and alkylene oxide is 1, and the rate constant &bgr; of the reaction between dialkanolamine and alkylene oxide not more than 0.7, when the reaction rate constant between monoalkanolamine and alkylene oxide is 1.
摘要:
Reactive distillation equipment applicable to a relatively complicated reaction composed of at least two steps of equilibrium reactions, and a reactive distillation method capable of performing the reaction efficiently. Raw material feeding pipes 5, 6 and 7 are connected to a reactive distillation column 1. The raw material feeding pipes 5, 6 and 7 are disposed on different stages of the reactive distillation column 1 in this order from the top of the column downward. It is preferred that the reactive distillation column 1 includes a stage to which no raw material feeding pipe is connected between a first stage connected to the raw material feeding pipe 5 and a second stage connected to the raw material feeding pipe 6, and between the second stage and a third stage connected to the raw material feeding pipe 7. By feeding raw material (A), raw material (B) and raw material (E) from the raw material feeding pipes 5, 6 and 7, respectively, vapor-liquid contacting of raw materials (A) and (B), and vapor-liquid contacting of product (C) and raw material (E) are carried out.
摘要:
A process is provided which comprises using a catalyst comprises a rare earth element supported on an inorganic heat-resisting carrier, when a monoethanolamine is selectively prepared by reacting an alkylene oxide with ammonia in a liquid phase. This catalyst has excellent monoalkanolamine selectivity and heat resistance; and therefore, even when the ratio of ammonia to the alkylene oxide is lower compared with cases where other catalysts are used, an equal or more amount of the monoalkanolamine can be formed, and thus the recovery cost of the unreacted ammonia is reduced. Further, since the total amount of the feed raw materials is reduced, apparatuses for the reaction system and recovery system can be made smaller, and thus the cost of equipment is reduced.
摘要:
A process is provided which comprises using a catalyst comprises a rare earth element supported on an inorganic heat-resisting carrier, when a monoethanolamine is selectively prepared by reacting an alkylene oxide with ammonia in a liquid phase. This catalyst has excellent monoalkanolamine selectivity and heat resistance; and therefore, even when the ratio of ammonia to the alkylene oxide is lower compared with cases where other catalysts are used, an equal or more amount of the monoalkanolamine can be formed, and thus the recovery cost of the unreacted ammonia is reduced. Further, since the total amount of the feed raw materials is reduced, apparatuses for the reaction system and recovery system can be made smaller, and thus the cost of equipment is reduced.
摘要:
A method for regeneration of catalyst which comprises phosphorus and alkali metal element and/or alkaline earth metal element and was deteriorated by use to produce aziridine compound represented by the general formula ##STR1## wherein R is hydrogen, a methyl group or an ethyl group, by a catalytic vapor-phase intramolecular dehydration reaction of alkanolamine represented by the general formula ##STR2## wherein R is as defined in the formula (II), X is OH or NH.sub.2, and Y is either NH.sub.2 when X is OH or OH when X is NH.sub.2, characterized in that the deteriorated catalyst is contacted with gaseous volatile phosphorus compound.
摘要:
An aromatic carbonate ester is continuously and efficiently prepared by the transesterification of an aromatic carboxylate with an aliphatic carbonate ester and/or aromatic.aliphatic carbonate ester. A raw material including an aromatic carboxylate, aliphatic carbonate ester and/or aromatic.aliphatic carbonate ester, and a catalyst are continuously fed to a first stage of a reactive distillation column (1) through a raw material feeding pipe (5). Meanwhile, an aliphatic carbonate ester (a) whose boiling point is lower than that of a reactant liquid that is present in a second stage lower than the first stage is continuously fed to the second stage through an aliphatic carbonate ester (a) feeding pipe (6). The second stage is preferably a column bottom section of the reactive distillation column (1). The amount of aliphatic carbonate ester (a) fed is preferably 0.001 to 5 times, by weight, more than the amount of the raw material fed.
摘要:
Carboxylate (1) of the formula R.sup.1 COOR.sup.2 (where each of R.sup.1 and R.sup.2 independently represents an alkyl group, an alicyclic hydrocarbon group or an aryl alkyl group), an aromatic hydroxy compound of the formula R.sup.3 OH (where R.sup.3 represents an aromatic group with or without a substituent), and a catalyst are supplied to a batch reactor 1, and a transesterification between the carboxylate (1) and the aromatic hydroxy compound is performed to produce carboxylate (3) of the formula R.sup.1 COOR.sup.3 (where R.sup.1 and R.sup.3 are as defined above). After distilling off the by-produced alcohol and unreacted compounds using a distillation column 2, carbonate ester (4) of the formula R.sup.4 O--COOR.sup.5 (where each of R.sup.4 and R.sup.5 independently represents an alkyl group, an alicyclic hydrocarbon group or an aryl alkyl group) is supplied to the batch reactor 1. Then, a transesterification between the carboxylate (3) and the carbonate ester (4) is performed to produce carbonate ester (5) of the formula R.sup.3 O--COOR.sup.6 (where R.sup.3 is as defined above, and R.sup.6 is a substituent selected from the group consisting of R.sup.3, R.sup.4 and R.sup.5). This process enables efficient preparation of carbonate esters.
摘要:
The present invention provides a process for more efficiently producing an α-hydroxycarboxylic acid ester wherein side reactions due to the α-hydroxycarboxylic acid ester are inhibited or prevented in comparison with prior art production processes.The invention provides a process for producing an α-hydroxycarboxylic acid ester comprising Steps 1 to 3:Step 1. reacting, in the presence of oxygen, (i) a 1,2-diol with a 1,2-diol or (ii) a 1,2-diol with an alcohol to obtain a reaction product containing an α-hydroxycarboxylic acid ester;Step 2. separating the α-hydroxycarboxylic acid ester from the reaction product obtained in Step 1 by distillation under reduced pressure; andStep 3. feeding Step 1 with a mixture obtained by partially or entirely removing water from the reaction product, wherein the mixture contains an unreacted 1,2-diol and/or alcohol.
摘要:
The present invention provides a process for more efficiently producing an α-hydroxycarboxylic acid ester wherein side reactions due to the α-hydroxycarboxylic acid ester are inhibited or prevented in comparison with prior art production processes. The invention provides a process for producing an α-hydroxycarboxylic acid ester comprising Steps 1 to 3: Step 1. reacting, in the presence of oxygen, (i) a 1,2-diol with a 1,2-diol or (ii) a 1,2-diol with an alcohol to obtain a reaction product containing an α-hydroxycarboxylic acid ester; Step 2. separating the α-hydroxycarboxylic acid ester from the reaction product obtained in Step 1 by distillation under reduced pressure; and Step 3. feeding Step 1 with a mixture obtained by partially or entirely removing water from the reaction product, wherein the mixture contains an unreacted 1,2-diol and/or alcohol.
摘要:
An alternative method for efficiently producing lactic acids from a carbohydrate-containing raw material such as cellulose is provided. The method for producing lactic acid and/or lactic acid ester comprises performing heat treatment on a carbohydrate-containing raw material in a solvent containing a catalyst, wherein the catalyst is at least one type of compound selected from the group consisting of a tin compound, an indium compound, and a rhenium compound, and the solvent contains water and/or alcohol.