Abstract:
Methods for producing lactams from oximes by performing a Beckmann rearrangement using a silicoaluminophosphate catalyst are provided. These catalysts may be used in gas phase or liquid phase reactions to convert oximes into lactams. High conversion of oxime and high selectivity for the desired lactams are produced using the disclosed methods, including high conversion and selectivity for ε-caprolactam produced from cyclohexanone oxime and high conversion and selectivity for ω-laurolactam produced from cyclododecanone oxime.
Abstract:
Provided is a method for producing an oxime compound with satisfactory selectivity. Provide is a method for producing an oxime represented by the following formula (II): wherein R1 and R2 are respectively the same as defined below, the method including oxidizing an amine represented by the following formula (I): wherein R1 and R2 each independently represents a hydrogen atom, an optionally substituted hydrocarbon group, or an optionally substituted heterocyclic group (provided that R1 and R2 are not simultaneously hydrogen atoms), or R1 and R2, together with the carbon atom to which R1 and R2 are attached, form an optionally substituted alicyclic hydrocarbon group having 3 to 12 carbon atoms [hereinafter sometimes referred to as the amine compound (I)], with oxygen in the presence of a layered silicate.
Abstract:
Cyclododecanone (CDON) is prepared by epoxidizing cyclododecene (CDEN) to epoxycyclododecane (CDAN epoxide), and rearranging the CDAN epoxide to CDON to obtain a mixture comprising said CDON and cyclododecane (CDAN), wherein CDAN is separated from the CDON-containing mixture and oxidized to CDON.
Abstract:
The present invention provides a continuous process for producing ammonium sulfate crystals, wherein said process comprises: (a) feeding to a first group of crystallization sections, which crystallization sections are heat integrated in series, a first aqueous ammonium sulfate solution that contains one or more impurities; (b) feeding to a second group of crystallization sections, which crystallization sections are heat integrated in series, a second aqueous ammonium sulfate solution that contains one or more impurities; (c) crystallizing ammonium sulfate crystals in each crystallization section respectively from each of said solutions of ammonium sulfate that contain one or more impurities; (d) purging a fraction of the ammonium sulfate solution that contains one or more impurities from each of said crystallization sections; and (e) discharging ammonium sulfate crystals from each crystallization section, characterized in that: (i) both the first group of crystallization sections and the second group of crystallization sections are together heat integrated in one series of crystallization sections; wherein the first group of crystallization sections operates at higher temperature than the second group of crystallization sections; and (ii) the composition of the first aqueous ammonium sulfate solution that contains one or more impurities is different to the composition of the second aqueous ammonium sulfate solution that contains one or more impurities. Further provided is apparatus suitable for producing ammonium sulfate crystals.
Abstract:
The invention relates to a method for preparing lactames, according to which a photonitrosation of a cycloalkane is carried out using nitrosyl chloride (NOCI). According to the invention, said photonitrosation is carried out by means of LEDs emitting a monochromatic light. The method according to the invention can also include a step comprising Beckmann transposition/dechlorination of the oxime hydrochloride generated during said phonitrosation, preferably carried out in a glass microreactor.
Abstract:
A method for producing a high purity, high quality amide compound, particularly a lactam. An amount of each of a halide, an aldehyde compound, an alcohol compound and a nitrile compound contained in a solution recycled into an oxime-forming step is controlled to an amount of 0.4 mol % or less based on the ketone as a starting material. One or more of a ketone, an oxime and an amide compound are purified by hydrogenation and/or crystallization for eliminating impurities containing a double bond. A content of impurities having a cyclic bridge structure is controlled using a cycloalkanone purified by recrystallization.
Abstract:
The present invention provides a method for separating an amide from an amino acid ionic liquid. The method includes the step of providing a polar solvent and an extracting agent to the amino acid ionic liquid, so as to separate the amide from the amino acid ionic liquid. In the method of the present invention, there is no need to add ammonium for neutralization, such that no byproduct, ammonium sulfate, is formed. In addition, after the amide is separated from the amino acid ionic liquid, the amino acid ionic liquid can be recycled.
Abstract:
The present invention relates to a method for producing a high purity, high quality amide compound, particularly, lactam. A first embodiment of the present invention is characterized in that an amount of each of a halide, an aldehyde compound, an alcohol compound and a nitrile compound contained in a solution recycled into an oxime-forming step is controlled to an amount of 0.4 mol % or less based on the ketone as a starting material. A second embodiment of the present invention is characterized in that one or more compounds selected from the group consisting of a ketone, an oxime and an amide compound are purified by hydrogenation and/or crystallization for eliminating impurities containing a double bond. A third embodiment of the present invention is characterized in that a content of impurities having a cyclic bridge structure is controlled by using a cycloalkanone purified by recrystallization.
Abstract:
The invention relates to a method for preparing lactames, according to which a photonitrosation of a cycloallcane is carried out using nitrosyl chloride (NOCI). According to the invention, said photonitrosation is carried out by means of LEDs emitting a monochromatic light. The method according to the invention can also include a step comprising Beckmann transposition/dechlorination of the oxime hydrochloride generated during said phonitrosation, preferably carried out in a glass microreactor.
Abstract:
The present invention provides a process for regenerating a catalyst for producing e-caprolactam comprising the steps of adsorbing a silicon compound on a zeolite catalyst that had been used for a Beckmann rearrangement reaction of cyclohexanone oxime and contacting the catalyst with an aqueous solution containing a compound selected from a quaternary ammonium compound, lower alkylamines and ammonia. The present invention also provides a process for producing e-caprolactam comprising subjecting cyclohexanone oxime to the Beckmann rearrangement reaction in the presence of the catalyst thus regenerated.