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.

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 CDEN, wherein CDEN is separated from the CDON-containing mixture and sent to the epoxidation to CDAN epoxide in step a.

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 CDEN, wherein CDEN is separated from the CDON-containing mixture and sent to the epoxidation to CDAN epoxide in step a.

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.

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 present invention provides an improved process for the recovery of -caprolactam from Nylon 6 comprising multi-component material, in particular multi-layered film. Further, the invention provides a plant configured to carry out the process of the invention, and the recovered e-caprolactam obtainable by the process of the invention that has a product carbon footprint of less than 2.5 kg CO.sub.2 equivalent per kg purified e-caprolactam (based on data originating from ecoinvent version 3.7.1; location: Europe).

The invention provides a process and a plant for the production of -caprolactam and crystalline ammonium sulfate in an industrial-scale plant, wherein the plant comprises a Beckmann rearrangement reaction section, an ammonium sulfate crystallization section, and one or more heat exchangers configured to transfer heat from the Beckmann rearrangement reaction section to the ammonium sulfate crystallization section and wherein the process comprises the steps of: a) feeding (i) cyclohexanone oxime and (ii) oleum and/or sulfuric acid to the Beckmann rearrangement reaction section b) reacting components (i) and (ii) in the Beckmann rearrangement reaction section to form a reaction mixture comprising -caprolactam, whereby heat of reaction is generated; c) discharging the reaction mixture comprising -caprolactam from the Beckmann rearrangement reaction section; d) removing partially or fully the heat of reaction generated in the Beckmann rearrangement reaction section by one or more heat exchangers configured to transfer heat from the Beckmann rearrangement reaction section; e) feeding an aqueous liquid comprising ammonium sulfate to the ammonium sulfate crystallization section; f) introducing heat into the ammonium sulfate crystallization section comprising the aqueous ammonium-sulfate-comprising liquid by one or more heat exchangers configured to transfer heat into the ammonium sulfate crystallization section; g) forming ammonium sulfate crystals by evaporative crystallization in the ammonium sulfate crystallization section;
characterized in that h) the heat of reaction removed from the Beckmann rearrangement reaction section in step d) is at least partially or fully transferred to the ammonium sulfate crystallization section in step f).

The invention provides a process and a plant for the production of -caprolactam and crystalline ammonium sulfate in an industrial-scale plant, wherein the plant comprises a Beckmann rearrangement reaction section, an ammonium sulfate crystallization section, and one or more heat exchangers configured to transfer heat from the Beckmann rearrangement reaction section to the ammonium sulfate crystallization section and wherein the process comprises the steps of: a) feeding (i) cyclohexanone oxime and (ii) oleum and/or sulfuric acid to the Beckmann rearrangement reaction section b) reacting components (i) and (ii) in the Beckmann rearrangement reaction section to form a reaction mixture comprising -caprolactam, whereby heat of reaction is generated; c) discharging the reaction mixture comprising -caprolactam from the Beckmann rearrangement reaction section; d) removing partially or fully the heat of reaction generated in the Beckmann rearrangement reaction section by one or more heat exchangers configured to transfer heat from the Beckmann rearrangement reaction section; e) feeding an aqueous liquid comprising ammonium sulfate to the ammonium sulfate crystallization section; f) introducing heat into the ammonium sulfate crystallization section comprising the aqueous ammonium-sulfate-comprising liquid by one or more heat exchangers configured to transfer heat into the ammonium sulfate crystallization section; g) forming ammonium sulfate crystals by evaporative crystallization in the ammonium sulfate crystallization section;
characterized in that h) the heat of reaction removed from the Beckmann rearrangement reaction section in step d) is at least partially or fully transferred to the ammonium sulfate crystallization section in step f).