Abstract: The present invention provides a process and a plant for recovering purified-caprolactam from polyamide 6 comprising fishing nets, wherein the plant comprises a depolymerization section [B], a recovery section [C], and a purification section [D]. The present invention also provides purified ?-caprolactam that has a particularly low product carbon footprint and is obtained via depolymerization of polyamide 6 from fishing nets.

Abstract: 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 CO2 equivalent per kg purified e-caprolactam (based on data originating from ecoinvent version 3.7.1; location: Europe).

Abstract: The present invention provides a process and a plant for recovering purified ?-caprolactam from nylon 6 comprising fishing nets, wherein the plant comprises a depolymerization section [B], a recovery section [C], and a purification section [D]. The present invention also provides purified ?-caprolactam that has a particularly low product carbon footprint and is obtained via depolymerization of nylon 6 from fishing nets. In a second preferred embodiment, the purification of the distilled caprolactam is achieved by crystallization in a process of concentrating. The crystallized caprolactam resulting from concentrating is generally sufficiently pure to be used directly. After crystallization, it may be necessary to purify the mother liquor by, for example, recycling it to the aqueous solution before the extraction with the alkyl phenol. The mother liquor can be purified for example by means of distillation.

Abstract: A continuous process for producing crystalline ammonium sulfate, said process comprising a start-up operation followed by a steady-state operation, wherein the start-up operation comprises: i) in a crystallizer, evaporating solvent from an approximately saturated ammonium sulfate solution; ii) replacing evaporated solvent with further approximately proximately saturated ammonium sulfate solution; iii) introducing to the crystallizer seed crystals of ammonium sulfate; iv) continuing to evaporate solvent, until a desired degree of supersaturation is reached; and v) recovering crystalline ammonium sulfate from ammonium sulfate solution in a recovery unit, and the steady-state operation comprises: vi) continuously feeding approximately saturated ammonium sulfate solution into the crystallizer and continuously withdrawing ammonium sulfate crystals from the crystallizer, such that the total combined volume of ammonium sulfate solution and ammonium sulfate crystals within the crystallizer remains constant; and vii)

Abstract: An industrial scale continuous process for the production and recovery of cyclohexanone from phenol and hydrogen, said process comprising: hydrogenating phenol in a phenol hydrogenation reactor; separating cyclohexanone from a hydrogenated product stream in a separation and purification section [II] comprising at least 4 distillation sections; wherein at least some of the reaction heat produced in the phenol hydrogenation reaction section [I] is applied for the production of steam; and wherein the molar ratio of cyclohexanone to phenol that is charged to said phenol hydrogenation reactor is from 0.02 to 0.10; and/or wherein the molar ratio of cyclohexanol to phenol that is charged to said phenol hydrogenation reactor is from 0.001 to 0.10.

Abstract: The present invention provides a continuous process for producing ammonium sulfate crystals, wherein said process comprises: i) feeding to a series of crystallization sections, which crystallization sections are heat integrated in series, a solution of ammonium sulfate; ii) crystallizing ammonium sulfate crystals from said solution of ammonium sulfate; iii) purging a fraction of the solution of ammonium sulfate from each of said crystallization sections; and iv) discharging ammonium sulfate crystals from each crystallization section, characterized in that: a fraction of said solution of ammonium sulfate is purged from at least one crystallization section to at least one other crystallization section; and an apparatus suitable for producing ammonium sulfate crystals.

Abstract: A process for the construction of a second chemical plant, which second chemical plant is suitable for the separation of cyclohexanone from a second mixture, which second mixture comprises reaction products from the hydrogenation of phenol. The process comprises providing a first chemical plant, which first chemical plant is suitable for the separation of cyclohexanone from a first mixture, and a second chemical plant comprising a distillation column suitable for distilling overhead cyclohexanone reused from the first chemical plant.

Abstract: An industrial scale continuous process for the production and recovery of cyclohexanone from phenol and hydrogen, said process comprising: hydrogenating phenol in a phenol hydrogenation reactor; separating cyclohexanone from a hydrogenated product stream in a separation and purification section [II] comprising at least 4 distillation sections; wherein at least some of the reaction heat produced in the phenol hydrogenation reaction section [I] is applied for the production of steam; and wherein the molar ratio of cyclohexanone to phenol that is charged to said phenol hydrogenation reactor is from 0.02 to 0.10; and/or wherein the molar ratio of cyclohexanol to phenol that is charged to said phenol hydrogenation reactor is from 0.001 to 0.10.

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 c

Abstract: A process for the construction of a second chemical plant, which second chemical plant is suitable for the separation of cyclohexanone from a second mixture, which second mixture comprises reaction products from the hydrogenation of phenol, said process comprising: a) providing a first chemical plant, which first chemical plant is suitable for the separation of cyclohexanone from a first mixture, which first mixture comprises reaction products from the oxidation of cyclohexane, and which first plant comprises: i) a distillation column (C) suitable for distilling overhead cyclohexane; ii) a distillation column suitable for distilling overhead cyclohexanone; iii) a cyclohexane oxidation unit (A) suitable for the oxidation of cyclohexane; and iv) a heat recovery unit (B) suitable for the recovery of heat from off-gas from the cyclohexane oxidation unit suitable for the oxidation of cyclohexane; b) disabling in said first chemical plant, said distillation column (C) suitable for distilling overhead cyclohexane, s

Abstract: The invention relates to a process for preparing a crystalline ammonium sulfate product, which process comprises: a) subjecting in a crystallizer a feed solution of ammonium sulfate to crystallization to form a first slurry of ammonium sulfate crystals; b) subjecting the first slurry of ammonium sulfate crystals to a first size classification to yield a first coarse ammonium sulfate crystal fraction and a first fine ammonium sulfate crystal fraction; c) recycling at least part of the first fine ammonium sulfate crystal fraction to the feed solution of ammonium sulfate; and d) recovering a crystalline ammonium sulfate product from the first coarse ammonium sulfate crystal fraction, characterized in that: e) a second size classification is carried out on a second slurry of ammonium sulfate crystals to yield a second coarse ammonium sulfate crystal fraction and a second fine ammonium sulfate crystal fraction.

Abstract: The present invention provides a process for continuously preparing a mixture of cyclohexanone and cyclohexanol comprising, a) hydrogenating phenol with gaseous hydrogen, in the presence of platinum or palladium, in a hydrogenation reactor, to produce a hydrogenation product stream comprising cyclohexanone, cyclohexanol, phenol and hydrogen; b) cooling the hydrogenation product stream to a temperature such that the fraction of phenol by mass in a first gas phase is lower than the fraction of phenol by mass in a first liquid phase; c) separating the first gas phase from the first liquid phase; d) returning at least part of the first gas phase to the hydrogenation reactor; e) heating the first liquid phase; f) purifying the first liquid phase by distillation; characterized in that heat is transferred from the hydrogenation product stream in step b) to another part of the process by means of in-process heat exchange; a mixture of cyclohexanone and cyclohexanol obtained by the process; and a chemical plant suitab