Provided are a method of preparing laurolactam including: a) synthesizing laurolactam by Bechmann rearrangement of cyclododecanone oxime under a catalyst system, b) mixing the laurolactam synthesized in a) with a good solvent and removing the catalyst system, and c) mixing the laurolactam from which the catalyst system has been removed in b) with a poor solvent and performing recrystallization, a synthesis device thereof, a laurolactam composition prepared therefrom, and a method of preparing polylaurolactam using the laurolactam composition.

The invention provides a process for the production of crystalline ammonium sulfate, wherein the process comprises performing a Beckmann rearrangement reaction, neutralizing the Beckmann rearrangement reaction mixture, separating a first aqueous ammonium sulfate phase and an aqueous ε-caprolactam phase, charging the first ammonium sulfate phase to a first evaporative type crystallization section wherein crystalline ammonium sulfate is obtained, discharging from the first evaporative type crystallization section mother liquor enriched in organic components, extracting the aqueous ε-caprolactam phase to obtain an extracted ε-caprolactam phase and a second aqueous ammonium sulfate phase, discharging the mother liquor that is discharged from the first evaporative type crystallization section and/or the second aqueous ammonium sulfate phase to a second evaporative type crystallization section wherein evaporative type crystallization is performed so that a three-phase system occurs. At least a liquid oily phase is recovered from the three-phase system. The invention further provides a plant suitable to carry out the process of the invention, crystalline ammonium sulfate and a liquid oily phase obtained by the process of the invention.

The invention provides a process for the production of crystalline ammonium sulfate, wherein the process comprises performing a Beckmann rearrangement reaction, neutralizing the Beckmann rearrangement reaction mixture, separating a first aqueous ammonium sulfate phase and an aqueous ε-caprolactam phase, charging the first ammonium sulfate phase to a first evaporative type crystallization section wherein crystalline ammonium sulfate is obtained, discharging from the first evaporative type crystallization section mother liquor enriched in organic components, extracting the aqueous ε-caprolactam phase to obtain an extracted ε-caprolactam phase and a second aqueous ammonium sulfate phase, discharging the mother liquor that is discharged from the first evaporative type crystallization section and/or the second aqueous ammonium sulfate phase to a second evaporative type crystallization section wherein evaporative type crystallization is performed so that a three-phase system occurs. At least a liquid oily phase is recovered from the three-phase system. The invention further provides a plant suitable to carry out the process of the invention, crystalline ammonium sulfate and a liquid oily phase obtained by the process of the invention.

The present invention provides a method for producing an epoxy compound by a reaction of an olefin compound with hydrogen peroxide, wherein the epoxy compound is stably and safely produced using a hydrogen peroxide stabilizer for reducing an oxygen gas generated from hydrogen peroxide. A method for producing an epoxy compound by a reaction of an olefin compound with hydrogen peroxide, wherein the reaction is carried out in the presence of an organophosphorus compound in such a reaction medium that the pH is maintained within a range of more than 7.5 and less than 12.0. The olefin compound may be 1,3,5-tris-(alkenyl)-isocyanurate. The alkenyl group in the olefin compound may be 3-butenyl group, 4-pentenyl group, 5-hexenyl group, 6-heptenyl group, or 7-octenyl group. The epoxy compound may be 1,3,5-tris-(epoxyalkyl)-isocyanurate. The reaction medium may be such a reaction medium that the pH is maintained within a range of 8.0 to 10.5.

The present invention provides a method for producing an epoxy compound by a reaction of an olefin compound with hydrogen peroxide, wherein the epoxy compound is stably and safely produced using a hydrogen peroxide stabilizer for reducing an oxygen gas generated from hydrogen peroxide. A method for producing an epoxy compound by a reaction of an olefin compound with hydrogen peroxide, wherein the reaction is carried out in the presence of an organophosphorus compound in such a reaction medium that the pH is maintained within a range of more than 7.5 and less than 12.0. The olefin compound may be 1,3,5-tris-(alkenyl)-isocyanurate. The alkenyl group in the olefin compound may be 3-butenyl group, 4-pentenyl group, 5-hexenyl group, 6-heptenyl group, or 7-octenyl group. The epoxy compound may be 1,3,5-tris-(epoxyalkyl)-isocyanurate. The reaction medium may be such a reaction medium that the pH is maintained within a range of 8.0 to 10.5.

The present invention relates to a process for purifying caprolactam from solutions of crude caprolactam by a direct treatment with one or more alkaline compounds of polyvalent metals, preferably bivalent and trivalent, without resorting to organic solvent extraction as used in the usual purification process. A further subject of the present invention is a facility devoid of a unit for organic solvent extraction and designed to carry out the caprolactam purification process described herein.

The present invention relates to a process for purifying caprolactam from solutions of crude caprolactam by a direct treatment with one or more alkaline compounds of polyvalent metals, preferably bivalent and trivalent, without resorting to organic solvent extraction as used in the usual purification process. A further subject of the present invention is a facility devoid of a unit for organic solvent extraction and designed to carry out the caprolactam purification process described herein.

A refining process includes steps of subjecting crude caprolactam to a first evaporative crystallization and a first solid-liquid separation to obtain a first caprolactam crystal and a first crystallization mother liquor; washing the first caprolactam crystal to obtain a second caprolactam crystal; optionally concentrating the first crystallization mother liquor to perform a second evaporative crystallization and a second solid-liquid separation to obtain a third caprolactam crystal and a second crystallization mother liquor; subjecting the third caprolactam crystal to a second washing to obtain a fourth caprolactam; optionally concentrating the second crystallization mother liquor to perform thermostatic crystallization, performing separation to obtain a fifth caprolactam crystal and a third crystallization mother liquor; washing the fifth caprolactam crystal to obtain a sixth caprolactam crystal; and subjecting the second caprolactam crystal to a hydrogenation reaction.

A refining process includes steps of subjecting crude caprolactam to a first evaporative crystallization and a first solid-liquid separation to obtain a first caprolactam crystal and a first crystallization mother liquor; washing the first caprolactam crystal to obtain a second caprolactam crystal; optionally concentrating the first crystallization mother liquor to perform a second evaporative crystallization and a second solid-liquid separation to obtain a third caprolactam crystal and a second crystallization mother liquor; subjecting the third caprolactam crystal to a second washing to obtain a fourth caprolactam; optionally concentrating the second crystallization mother liquor to perform thermostatic crystallization, performing separation to obtain a fifth caprolactam crystal and a third crystallization mother liquor; washing the fifth caprolactam crystal to obtain a sixth caprolactam crystal; and subjecting the second caprolactam crystal to a hydrogenation reaction.

A refining process includes steps of subjecting crude caprolactam to a first evaporative crystallization and a first solid-liquid separation to obtain a first caprolactam crystal and a first crystallization mother liquor; washing the first caprolactam crystal to obtain a second caprolactam crystal; optionally concentrating the first crystallization mother liquor to perform a second evaporative crystallization and a second solid-liquid separation to obtain a third caprolactam crystal and a second crystallization mother liquor; subjecting the third caprolactam crystal to a second washing to obtain a fourth caprolactam; optionally concentrating the second crystallization mother liquor to perform thermostatic crystallization, performing separation to obtain a fifth caprolactam crystal and a third crystallization mother liquor; washing the fifth caprolactam crystal to obtain a sixth caprolactam crystal; and subjecting the second caprolactam crystal to a hydrogenation reaction.