Color-stable aqueous mixture comprising recycled liquid caprolactam

Abstract

A method for preparing liquid ε-caprolactam mixture M F A method, the method including providing a stream S M The flow contains a solid material M containing polyamide 6; preparation based on S M Aqueous depolymerization mixture; the depolymerization mixture is reacted in reaction unit U R By subjecting polyamide 6 to depolymerization conditions, a liquid aqueous stream S containing ε-caprolactam dissolved in water was obtained. R The S stream R Further comprising one or more impurities; and optionally the liquid aqueous stream S R Transferred to evaporation unit U E In the middle, by S R Obtain a liquid aqueous stream S containing ε-caprolactam dissolved in water. L ; Make the flow S R Optionally, this stream S L Transferred to ε-caprolactam purification unit U P In, and from that unit U P To obtain the mixture M F ; or from this unit U P Obtain mixture M T The mixture has at least 99% ε-caprolactam purity Ω GC (M T APHA value of up to 20 Ω APHA (M T ) and based on the mixture M T Total weight at most 0.05 wt% water content x H2O (M T ), and to the mixture M T Add water to obtain mixture M. F ; wherein the mixture M F It has at least 99% purity of ε-caprolactam Ω GC (M F APHA value of up to 20 Ω APHA (M F ) and based on the mixture M F The total weight must contain at least 0.1% water by weight. H2O (M F ).

Description

[0001] This invention relates to a method for preparing a high-purity liquid mixture containing ε-caprolactam and color-stable when stored at low temperatures, wherein the mixture is prepared by subjecting a solid material containing polyamide 6 to hydrolysis and depolymerization, and purifying the resulting depolymerized mixture relative to ε-caprolactam. Further, this invention relates to a method for storing the mixture, and further to the corresponding stored mixture. Still further, this invention relates to the use of the optionally stored mixture for the preparation of polyamide 6, and thus to a full polyamide 6 (or ε-caprolactam) recycling loop.

[0002] With the formula (-NH-(CH2)5-CO-) n Polyamide 6, characterized by its polyamide composition, can be found in many materials, such as packaging, automotive engineering plastics, and textile filaments. The latter accounts for approximately 40% of the global polyamide 6 market. Currently, only a very small percentage of textile filaments are recycled, yet this accounts for a large percentage of global CO2 emissions. Therefore, there is a need to recycle polyamide 6 from such materials. For example, due to the various possible chemical compositions of waste containing polyamide 6, these wastes form exfoliants for recycling methods, making the purification process for ε-caprolactam downstream of the depolymerization step a challenging task. Once a correspondingly purified mixture containing ε-caprolactam is obtained from the depolymerization and downstream purification stages, it is advantageous to reuse such mixtures as exfoliants for polymerization, particularly for the preparation of polyamide 6, thus achieving a recycling loop. However, it cannot be guaranteed that such mixtures can be used as exfoliant materials immediately after their preparation. Typically, the mixtures will need to be stored for a certain period of time before further use. In this regard, it is necessary to maintain the quality of the mixture substantially constant throughout its process, particularly in terms of color characteristics, most commonly expressed as APHA color values. The APHA color scale, also known as the Hazen scale or platinum-cobalt scale, is a color standard named by the American Public Health Association. Furthermore, it is desirable that this type of storage can be carried out under economically favorable conditions, such as relatively low temperatures.

[0003] WO 2023 / 144338 A1 discloses a method for recovering purified ε-caprolactam from a material derived from a fishing net containing polyamide 6 in an apparatus, wherein the apparatus includes a depolymerization section, a recovery section and a purification section.

[0004] Surprisingly, it was found that the high-purity mixture of ε-caprolactam, obtained by hydrolysis and depolymerization followed by purification and exhibiting a certain minimum water content, possessed the desired storage properties.

[0005] Therefore, the present invention relates to a method for preparing liquid ε-caprolactam mixture M F The method includes

[0006] (i) Provide stream S M The stream contains a solid material M containing polyamide 6;

[0007] (ii) Preparation based on S M Aqueous depolymerization mixtures;

[0008] (iii) The depolymerized mixture prepared according to (ii) is reacted in reaction unit U R The polyamide 6 was subjected to depolymerization conditions to obtain a product containing polyamide 6 at a concentration of c. SR Liquid aqueous flow S of ε-caprolactam dissolved in water R The stream S R It further contains one or more impurities; and optionally the liquid aqueous stream S R Transferred to evaporation unit U E In the middle, by S R Obtain the concentration c SL Liquid aqueous flow S of ε-caprolactam dissolved in water L , where c SL > c SR And further by S R Obtain one or more water vapor streams S V ;

[0009] (iv) The stream S R Optionally, this stream S L Transferred to ε-caprolactam purification unit U P In the middle, and

[0010] (iv.1) From this unit U P To obtain the mixture M F ;or

[0011] (iv.2) From this unit U P Obtain mixture M T The mixture has at least 99% ε-caprolactam purity Ω GC (M T APHA value of up to 20 Ω APHA (M T ) and based on the mixture M T Total weight at most 0.05% by weight of water content x H2O (M T ), and to the mixture M T Add water to obtain mixture M. F ;

[0012] Wherein the mixture M F It has at least 99% purity of ε-caprolactam Ω GC (MF APHA value of up to 20 Ω APHA (M F ) and based on the mixture M F The total weight must be at least 0.1 wt% water content x H2O (M F ).

[0013] Preferably, the mixture M comprises at least 99% by weight, preferably at least 99.1% by weight, more preferably at least 99.2% by weight, more preferably at least 99.3% by weight, more preferably at least 99.4% by weight, more preferably at least 99.5% by weight, more preferably at least 99.6% by weight, more preferably at least 99.7% by weight, more preferably at least 99.8% by weight, and more preferably at least 99.9% by weight. F It is composed of ε-caprolactam and water.

[0014] Ω is preferred. GC (M F The content is at least 99.5%, more preferably at least 99.6%, more preferably at least 99.7%, more preferably at least 99.8%, and more preferably at least 99.9%. Further, preferably, Ω APHA (M F The value is at most 15, more preferably at most 12.5, more preferably at most 10, more preferably at most 7.5, and more preferably at most 5. Furthermore, it is preferred that x H2O (M F The content is in the range of 0.1 to 10 wt%, more preferably in the range of 0.15 to 9 wt%, more preferably in the range of 0.2 to 8 wt%, more preferably in the range of 0.35 to 7 wt%, and more preferably in the range of 0.5 to 6 wt%. H2O (M F Suitable ranges for M may include 0.5 to 2 wt%, 2 to 4 wt%, and 4 to 6 wt%. Therefore, such a mixture M F It is more preferred, where Ω GC (M F It is at least 99.9%, Ω APHA (M F It is at most 5%, and x H2O (M F (In the range of 0.5 to 6% by weight)

[0015] Preferably, mixture M F It has a temperature in the range of 20°C to 80°C, more preferably in the range of 35°C to 77°C, and even more preferably in the range of 50°C to 75°C.

[0016] Optionally or preferably, mixture M F A further characteristic is that the permanganate absorbance number Ω PAN (M F ) and UV absorbance Ω UV (M F One or more of the following: Ω PAN (M F Preferably, the number is at most 20, more preferably at most 15, and even more preferably at most 10. Ω UV (M F Preferably, it is at most 0.75, more preferably at most 0.25, and even more preferably at most 0.1. Therefore, such a mixture M... F It is more preferred, where Ω PAN (M F It is at most 10 and Ω UV (M F The concentration is at most 0.1. Therefore, a mixture M is more preferably such that... F , where Ω GC (M F It is at least 99.9%, Ω APHA (M F It is at most 5, x H2O (M F Ω is in the range of 0.5 to 6 wt%. PAN (M F It is at most 10 and Ω UV (M F The value is at most 0.1.

[0017] About Ω GC Ω APHA Ω UV and Ω PAN For the determination of the value, please refer to the reference example below.

[0018] Preferably, according to the present invention, the purification unit U according to (v) P Including water separation unit U WS and distillation unit U D And the method preferably includes transferring the stream S R Optional flow S L Feed to U WS From U WS Obtain the concentration c UWS The flow of ε-caprolactam S UWS , will the stream S UWS Feed into the distillation unit U D From U D Obtain the concentration c MF M of ε-caprolactamF , where c SR < c UWS <<< c MF Preferably, where c SL < c UWS <<< c MF .

[0019] Compared to the symbol "<", the symbol "<<<" indicates, for example, a ratio c. UWS / c SR Significantly lower than the ratio c MF / c UWS .

[0020] More preferably, the water separation unit U WS Includes at least two water ion units U WS1 and U WS2 Preferably, two water ion units U connected in series WS1 and U WS2 Among them, flow S R Optional flow S L Feed into U WS1 In, among them in U WS1 Downstream and in U WS2 Upstream, a separation unit U is preferably provided. I The method includes from U WS1 Obtaining water flow S UWS1 , will the stream S UWS1 Feed into the separation unit U I In the middle, from U I Obtaining water flow S UI and the stream S UI Feeding into unit U WS2 In, among them in U I In the middle, from S UWS1 One or more impurities can be separated from U, thereby separating them from U. I Obtain impurity flow S I The impurity preferably comprises at least one of the impurities contained in S according to (iii). R Impurities in the separation unit U, wherein at least one of the impurities is an organic compound having a higher boiling point than ε-caprolactam. I It is a high-boiling-point separation unit.

[0021] Regarding subunit U WS1 and subunit U WS2 In a specific device design, it is preferable that the subunit U WS1Includes one or more of falling film evaporators, flash tanks, forced circulation evaporators, and distillation columns, more preferably one or more of falling film evaporators and flash tanks, and subunit U WS2 It includes one or more of falling film evaporators, flash tanks, and distillation columns, more preferably distillation columns.

[0022] Regarding the high-boiling-point separation unit U I There are no specific limitations, provided that in the unit U I In this process, compounds with boiling points higher than ε-caprolactam can be separated at least partially. It has been found that the waste material M, most preferably used according to (i), will contain certain compounds that, before or after the depolymerization of polyamide 6 according to (iii), produce a stream containing ε-caprolactam and compounds with boiling points higher than ε-caprolactam. However, due to the potentially different chemical compositions of the waste material, these compounds with boiling points higher than ε-caprolactam will often vary in both content and chemical properties in the stream to be purified. According to the preferred process stage of the invention, unit U... I The separation of high-boiling substances in the above includes

[0023] (α) From the water ion unit U WS1 Obtain flow S UWS1 The flow has a temperature T UWS1 And it shows the total concentration c of one or more compounds Ψ. L0 (Ψ), one or more of these compounds have a higher boiling point than ε-caprolactam, and further have a concentration c L0 (C) monomer ε-caprolactam;

[0024] (β) in evaporation unit U E1 The middle of the flow S UWS1 Generates at least a partial vapor stream S of water V1 and liquid flow S L1 It includes

[0025] (β.1) This stream S UWS1 Transmitted to this unit U E1 In this unit U E1 The middle of the flow S UWS1 Preparation at evaporation pressure p E1 Below has an evaporation temperature T E1 Evaporated mixture M E1 T E1 > T UWS1 Wherein the evaporation pressure p E1 Below, one or more organic compounds Ψ have a boiling point T. BX Furthermore, ε-caprolactam has a boiling point T.BC T BX > T E1 ≥ T BC ;

[0026] (β.2) From this evaporation unit U E1 Remove the stream S from the middle V1 The stream S V1 With temperature T V1 T V1 ≤ T E1 And exhibits the total concentration c of one or more compounds Ψ. V1 (Ψ) and the concentration of monomer ε-caprolactam c V1 (C), where c V1 (C)> c UWS1 (C) and c V1 (Ψ) < c UWS1 (Ψ);

[0027] (β.3) From this evaporation unit U E1 Remove the S stream from the middle L1 The stream S L1 With temperature T L1 T L1 = T E1 And exhibits the total concentration c of one or more compounds Ψ. L1 (Ψ) and the concentration of monomer ε-caprolactam c L1 (C), where c L1 (C) <c E1 (C) and c L1 (Ψ) > c UWS1 (Ψ);

[0028] (γ) in the separation unit U S1 The middle of the flow S V1 Generates water vapor stream S V2 and liquid flow S L2 It includes

[0029] (γ.1) will be derived from the evaporation unit U according to (β.2). E1 The stream S removed from the middle V1 Optionally, it is transferred to the separation unit U after cooling. S1 In, and make the flow S V1 Optionally, after cooling, the flow in the separation unit U S1 The middle undergoes separation conditions;

[0030] (γ.2) From this separation unit U S1 Remove the S stream from the middle V2 The stream S V2With temperature T V2 T UWS1 < T V2 ≤T V1 And exhibits the total concentration c of one or more compounds Ψ. V2 (Ψ) and the concentration of monomer ε-caprolactam c V2 (C);

[0031] (γ.3) From this separation unit U S1 Remove the S stream from the middle L2 The stream S L2 With temperature T L2 T L2 = T V2 And exhibits the total concentration c of one or more compounds X. L2 (Ψ) and the concentration of monomer ε-caprolactam c L2 (C), where c L2 (Ψ)> c V2 (Ψ) and c L2 (C) < c V2 (C);

[0032] (δ) will be derived from the separation unit U according to (γ.2). S1 The obtained water flow S V2 Transferred to the water ion unit U WS2 .

[0033] Typically, it is preferred to prepare mixture M E1 This includes stirring, preferably mechanical stirring, and more preferably agitation. Therefore, unit U E1 Preferably, it includes a stirred reactor, more preferably a stirred tank reactor, and even more preferably a continuous stirred tank reactor. Separation unit U S1 Preferably, it includes a droplet separator, more preferably it is composed of such a separator, which is preferably selected from a group consisting of a hydrocyclone, a demister and an absorption tower, more preferably a hydrocyclone.

[0034] Regarding the flow S according to (α) UWS1 Temperature T UWS1 T is preferred. UWS1 The temperature range is 75°C to 120°C, more preferably 80°C to 110°C, and even more preferably 85°C to 100°C. Regarding the flow S UWS1 In terms of chemical composition, concentration c is preferred. UWS1 (C) and c UWS1 The sum of (Ψ) (i.e., c) UWS1 (C) + c UWS1(Ψ)) is at least 60% by weight, more preferably in the range of 60 to 95% by weight, more preferably in the range of 70 to 90% by weight, and more preferably in the range of 80 to 85% by weight, in each case based on the flow S UWS1 The total weight. Furthermore, in flow S UWS1 In this process, the weight ratio of one or more compounds Ψ to the monomer ε-caprolactam is preferably in the range of 50:50 to 5:95. Suitable ranges include, for example, 50:50 to 40:60, or 45:50 to 35:65, or 40:60 to 30:70, or 35:65 to 25:75, or 30:70 to 20:80, or 25:75 to 15:85, or 20:80 to 10:90, or 15:85 to 5:95. According to the invention, particularly when the method of the invention is carried out as a continuous method, S UWS1 The concentration of Ψ can vary over time, depending on which specific material M is fed into the method. Particularly in this case, the high-boiling-point separation of the present invention allows for the production of high-boiling-point concentrations c that are substantially constant and very low. V2 (Ψ) of the flow S V2 .

[0035] Regarding the chemical properties of high-boiling compounds, there is a relatively high degree of uncertainty solely due to the unpredictable chemical composition of the materials undergoing depolymerization and ultimately high-boiling separation according to the present invention. However, in developing the method of the present invention, numerous complex experiments were conducted, and it was found that in most cases, the flow S UWS1 The one or more compounds Ψ contained herein preferably include at least one of the following

[0036] - At least one aromatic amine, including at least one of aromatic monoamines, aromatic diamines, aromatic triamines and aromatic tetraamines;

[0037] - At least one aliphatic amine, including at least one of aliphatic monoamine, aliphatic diamine and aliphatic triamine;

[0038] -At least one aliphatic amide;

[0039] - At least one aromatic alcohol, including at least one of aromatic monools and aromatic diols;

[0040] - At least one aliphatic alcohol, including at least one of aliphatic monools and aliphatic diols;

[0041] -At least one aromatic acid;

[0042] -At least one aliphatic acid;

[0043] -At least one ε-caprolactam oligomer;

[0044] - At least one additional compound selected from the group consisting of: one or more dye pyrolysis products such as optionally chlorinated aromatic diamines, one or more water-soluble oligocellulose pyrolysis products, and one or more water-soluble oligomers of terephthalic acid and hexamethylenediamine.

[0045] Furthermore, it was discovered that...

[0046] - At least one aromatic amine preferably includes one or more of the following: 4,4'-methylenediphenylamine (MDA), its isomers such as 2,4'-methylenediphenylamine and 2,2'-methylenediphenylamine, and polymethylene polyphenylene polyamine (pMDA).

[0047] - At least one aliphatic amine and at least one aliphatic amide preferably include one or more of the following: hexamethylenediamine adipate, 6-aminohexanoic acid and its oligomers (including 6-aminohexanoic acid dimers and higher oligomers, such as 6-aminohexanoic acid trimers, 6-aminohexanoic acid tetramers, 6-aminohexanoic acid pentamers, 6-aminohexanoic acid hexamers), N'-(6-aminohexyl)hexane-1,6-diamine, N-methylhexane-1,6-diamine, 6-aminohexamide, and derivatives of ε-caprolactam (such as 1-(6-aminohexyl)azacycloheptane-2-one) that have a boiling point higher than that of ε-caprolactam, excluding ε-caprolactam oligomers.

[0048] - At least one aliphatic alcohol preferably includes one or more of the following: butanediol and its oligomers, including butanediol dimers and higher oligomers (such as butanediol trimers), including polytetrahydrofuran;

[0049] - At least one aromatic acid and at least one aliphatic acid preferably include one or more of terephthalic acid and adipic acid;

[0050] - At least one ε-caprolactam oligomer preferably includes one or more of the following: ε-caprolactam dimer, ε-caprolactam trimer, ε-caprolactam tetramer, ε-caprolactam pentamer and ε-caprolactam hexamer.

[0051] According to the present invention, it is further preferred that the purification unit U P In distillation unit U D The downstream of the crystallization unit U CR and chemical processing unit U OD One or more of them, and the method preferably includes from U CR China or from U OD Obtain mixture M F .

[0052] Regarding unit U OD Regarding the chemical treatment in the process, the method of the present invention preferably includes:

[0053] (a) Provide from this distillation unit U D The preferred liquid flow S containing ε-caprolactam UD Or from this crystallization unit U CR The preferred liquid flow S containing ε-caprolactam CR The flow S UD or the flow S CR Further comprising one or more oxidizable organic impurity compounds X, wherein the stream S UD Or the stream S CR It has at least 99% purity of ε-caprolactam Ω GC (S C And it shows the weight ratio r of one or more organic compounds X relative to ε-caprolactam. XC ;

[0054] (b) Providing a flow containing at least one permanganate S O ;

[0055] (c) From this flow S UD and the S stream O Or by the flow S SCR and the S stream O Preparation of Oxidation Reaction Separate Mixture M OE And make the mixture M OE Under oxidative reaction conditions, an oxidation product stream S containing ε-caprolactam was obtained. P The oxidation product stream further comprises one or more oxidation products Y obtained by oxidation of at least a portion of the one or more compounds X, and optionally further comprises a portion of the one or more organic compounds X, wherein the stream S P The weight ratio r of organic compound X relative to ε-caprolactam is shown. XCP , where 0 ≤ r XCP < r XC Furthermore, it demonstrates the weight ratio r of one or more products Y relative to ε-caprolactam. YCP , where r YCP > 0;

[0056] (d) From the stream S P The mixture M is obtained by separating at least a portion of one or more oxidation products Y and optionally at least a portion of organic compound X. F Or the mixture M T It exhibits a weight ratio r of oxidation product Y to ε-caprolactam.YCT , where 0 ≤ r YCT < r YCP Furthermore, it demonstrates the weight ratio r of organic compound X relative to ε-caprolactam. XCT , where 0 ≤ r XCT < r XC .

[0057] Included in the stream S provided according to (b) O At least one permanganate in the composition preferably comprises at least an alkali metal permanganate, more preferably composed of the alkali metal permanganate, and more preferably, the at least one alkali metal permanganate comprises one or more of sodium permanganate and potassium permanganate. Preferably, 0.5 to 100 wt% of the flow S provided according to (b) O It is composed of permanganate. Therefore, it is generally conceivable to use permanganate in its solid form. Preferably, according to the flow S provided in (b) O Further comprising water, wherein more preferably, the oxidation reaction precipitate mixture M prepared according to (c) OE The concentration of permanganate calculated as MnO4 is exhibited in the range of 0.005 to 5 wt%, more preferably in the range of 0.01 to 3 wt%, and even more preferably in the range of 0.05 to 1 wt%. Furthermore, the oxidation reaction conditions according to (c) preferably include a mixture of MnO4. OE Temperature T in the range of 40°C to 140°C, more preferably in the range of 60°C to 100°C, and even more preferably in the range of 70°C to 90°C OE Furthermore, more preferably, the mixture M prepared according to (c) OE It further contains water. Preferably, the mixture M... OE Subjected to oxidation reaction conditions in the chemical processing unit U OD The oxidation reaction unit U in OR The process is carried out in which the unit U OR Preferably, it includes one or more of at least one continuous stirred tank reactor and at least one tubular reactor.

[0058] More preferably, the method of the present invention further includes providing a stream S containing at least one hydroxide. B The mixture M, which is the precipitate from the oxidation reaction of (c), is... OE By flow S UD or flow S CR and by flow S O He Liu S B Preparation. Contained in flow S BAt least one hydroxide in the solution preferably comprises at least an alkali metal hydroxide, more preferably composed of, wherein more preferably, the at least one alkali metal hydroxide comprises sodium hydroxide, more preferably composed of, it. Preferably, 0.5 to 100 wt% of the flow S B It consists of hydroxides. Therefore, it is generally conceivable to use hydroxides in their solid form. Preferably, the flow S B Further comprising water, wherein more preferably, the oxidation reaction precipitate mixture M prepared according to (c) OE It exhibits a hydroxide concentration calculated in OH within the range of 0.005 to 0.75 wt%, more preferably within the range of 0.01 to 0.5 wt%, and even more preferably within the range of 0.1 to 0.25 wt%.

[0059] Preferably, according to the present invention, one or more oxidizable organic compounds X have a boiling point δ X / °C, where 0.5 ≤ (δ X / δ C ) ≤ 1.5, δ C / °C is the boiling point of ε-caprolactam, and at least one of the one or more oxidation products Y has a boiling point δ. Y / °C, where δ Y / °C ≠ δ C / °C, where the boiling point δ Y With boiling point δ C The temperature difference Δδ is preferably at least 1°C. Typically, one or more oxidizable organic compounds X will have a higher boiling point than ε-caprolactam; however, it is conceivable that there are oxidizable organic compounds with lower boiling points than ε-caprolactam, such as certain aldehydes and / or ketones.

[0060] According to the present invention, it is preferable that, according to (d) from the flow S P Separating at least a portion of one or more oxidation products Y and optionally at least a portion of an organic compound X from the fluid comprises making the stream S obtained according to (c) P In distillation unit U DT The process involves distillation, and the distillation unit includes a chemical processing unit U. OD This is part of the chemical processing unit. In this case, it is from the distillation unit U containing ε-caprolactam. DT Obtain flow S DT Among them, this flow S DT It is a mixture M F or mixture M T Preferably, unit U DTIt includes one or more distillation columns, more preferably one or two distillation columns, wherein at least one distillation column is optionally configured as a sidestream column or a split-wall column. According to the method of the invention, distillation unit U can be... DT Designed to accomplish one of the following separation tasks:

[0061] Simple evaporation of ε-caprolactam;

[0062] - Separation of one or more light-boiling-point compounds from ε-caprolactam;

[0063] - Separation of one or more high-boiling-point compounds from ε-caprolactam;

[0064] - Separation of one or more high-boiling-point compounds and one or more low-boiling-point compounds with ε-caprolactam

[0065] --In a side-flow distillation column; or

[0066] --In two separate distillation columns; or

[0067] --In a wall distillation column; or

[0068] --In a side-stream distillation column and another distillation column, wherein in the other distillation column...

[0069] ---One or more light-boiling-point compounds; or compounds contained therein

[0070] ---One or more high-boiling compounds

[0071] Separate from ε-caprolactam.

[0072] Preferably, the stream S obtained from (c) is made to undergo separation according to (d) before being subjected to separation. P Filtered.

[0073] According to the method of the present invention, purification unit U P It may further include crystallization unit U CR The method includes distillation from distillation unit U D Obtain the concentration c UD The flow of ε-caprolactam S UD and the stream S UD Feeding to crystallization unit U CR From U CR Obtain the concentration c MF M of ε-caprolactam F .

[0074] Further according to the present invention, purification unit U P It may further include a chemical processing unit U ODThe method includes distillation from distillation unit U D Obtain the concentration c UD The flow of ε-caprolactam S UD and the stream S UD Feed to chemical processing unit U OD From U OD Obtain the concentration c MF M of ε-caprolactam F .

[0075] Furthermore, according to the present invention, the purification unit U P It may further include a chemical processing unit U OD and crystallization unit U CR The crystallization unit U CR Located in distillation unit U D Downstream of, and the chemical processing unit U OD Located in the crystallization unit U CR Downstream, wherein the method includes distillation unit U D Obtain the concentration c UD The flow of ε-caprolactam S UD , will the stream S UD Feeding to crystallization unit U CR From crystallized U CR Obtain the concentration c CR The flow of ε-caprolactam S CR and the stream S CR Feed to chemical processing unit U OD From U OD Obtain the concentration c MF M of ε-caprolactam F .

[0076] Furthermore, according to the present invention, the purification unit U P It may further include a chemical processing unit U OD and crystallization unit U CR The chemical processing unit U OD Located in distillation unit U D Downstream of, and the crystallization unit U CR Located in unit U CR Downstream, wherein the method includes distillation unit U D Obtain the concentration c UD The flow of ε-caprolactam S UD , will the stream S UD Feed to chemical processing unit U OD From chemical processing unit U OD Obtain the concentration c ODThe flow of ε-caprolactam S OD and the stream S OD Feeding to crystallization unit U CR From U CR Obtain the concentration c MF M of ε-caprolactam F .

[0077] As described above, according to (iv.2), the method of the present invention may include flowing S R Optional flow S L Transferred to ε-caprolactam purification unit U P In, and from that unit U P Obtain mixture M T The mixture has at least 99% ε-caprolactam purity Ω GC (M T APHA value of up to 20 Ω APHA (M T ) and based on the mixture M T Total weight at most 0.05% by weight of water content x H2O (M T Preferably, x H2O (M T The concentration is in the range of 0 to 0.05% by weight, more preferably in the range of 0 to 0.01% by weight, and even more preferably in the range of 0 to 0.001% by weight. Further preferably, Ω GC (M T The content is at least 99.5%, more preferably at least 99.8%, and even more preferably at least 99.9%. Further preferably, Ω... APHA (M T The value is at most 20, more preferably at most 15, and even more preferably at most 10. Therefore, more preferably, x H2O (M T Within the range of 0 to 0.001 wt%, Ω GC (M T It is at least 99.9%, and Ω APHA (M T () is at most 10.

[0078] Optionally or preferably, mixture M T A further characteristic is that the permanganate absorbance number Ω PAN (M T ) and UV absorbance Ω UV (M T One or more of ) where Ω PAN (M TThe value is at most 20, preferably at most 15, more preferably at most 10, and wherein Ω UV (M T The value is at most 0.75, preferably at most 0.25, and more preferably at most 0.1. Therefore, more preferably, x H2O (M T Within the range of 0 to 0.001 wt%, Ω GC (M T It is at least 99.9%, Ω APHA (M T It is at most 10, Ω PAN (M T ) is at most 10, and Ω UV (M T The value is at most 0.1.

[0079] As described above, according to (i), flow S is provided. M The stream contains a solid material M containing polyamide 6. Preferably, material M comprises waste, preferably composed of waste, wherein the waste more preferably comprises one or more of at least one textile waste and at least one engineering plastic waste, more preferably composed of one or more of at least one textile waste and at least one engineering plastic waste, more preferably comprising at least one textile waste, more preferably composed of at least one textile waste;

[0080] Preferably, the material M is composed of polyamide 6 in an amount of 10 to 99 wt%, more preferably 30 to 98.5 wt%, more preferably 50 to 98 wt%, and even more preferably 80 to 98 wt%.

[0081] Preferably, in addition to polyamide 6, the material M also contains one or more other organic polymer compounds, which more preferably include, but are not limited to, one or more of the following: at least one polyurethane elastic fiber, at least one polyethylene terephthalate, at least one polytetrahydrofuran, at least one polyamide 6.6, at least one polyurethane, at least one polyester, at least one cellulose material, and at least one rubber material, which includes one or more of at least one natural rubber material and at least one synthetic rubber material.

[0082] Prior to the method of the present invention, the collected textile waste can be suitably sorted. In this regard, the collected textile waste can be spread on a conveyor, which can be done manually and / or mechanically. Thereafter, the spread textile waste is sorted by composition and / or by color. Sorting can be done manually and / or optically. If optically, sorting preferably includes infrared sorting, more preferably near-infrared sorting and / or mid-infrared sorting. Optionally, prior to sorting, the textile waste can be subjected to a suitable metal removal step. If a metal removal step is performed, iron elements are preferably separated, for example, by a suitable magnetic device, and / or non-ferrous elements are preferably separated, for example, by a suitable eddy current separation device. After the sorting, the resulting textile waste can be subjected to further processing, such as cutting and / or shredding.

[0083] Typically, the solid material M can be provided by any suitable method. Preferably, according to the invention, providing the solid material M includes delivery in the delivery unit U. MD Provides solid material M, where U MD Preferably, it includes one or more of at least one large bag station and at least one bulk container station; the provided solid material M is delivered from unit U via a first connecting pipeline. MD Transferred to material collection unit U MC Preferably, a collecting drum is used, wherein the first connecting pipeline preferably includes at least one material receiving and discharging unit U. MRD At least one first material feeding unit U FMF and at least one first particle separation unit U FMPS One or more of them; the solid material M is taken from the unit U MC Transmitted to unit U via the second connecting pipeline M The second connecting pipeline preferably includes at least one second material feeding unit U. SMF At least one second particle separation unit U SMPS and one or more of at least one metal detector.

[0084] Typically, solid material M can be supplied from different sources if desired. For example, as a source of solid material M, collected textile waste can originate from different textile waste sources and can be combined, and the collected textile waste can then be appropriately sorted as described above. Textile waste can typically have different grades of quality, different grades of impurities, and different combinations of materials. However, such materials are of course suitable for the method according to the invention. ε-caprolactam used in the method according to the invention can be obtained via hydrolysis and depolymerization as described in the context of the invention and subsequent purification, depending on the source and quality of the collected and sorted materials, which may result in slight variations in the properties of solid material M, while the solid material is still of course suitable for the method described herein.

[0085] Preferably, the solid material M is provided in the form of particles, wherein the particle size distribution is preferably characterized by one or more of the following pairs of values, preferably two or more of the following pairs of values, and more preferably three of the following pairs of values:

[0086] - D10 values ​​for particle width in the range of 0.1 to 15 mm and D10 values ​​for particle length in the range of 0.3 to 15 mm;

[0087] - D50 values ​​for particle width in the range of 0.2 to 20 mm and D50 values ​​for particle length in the range of 0.5 to 20 mm;

[0088] - D90 values ​​for particle width in the range of 0.3 to 30 mm and D90 values ​​for particle length in the range of 0.8 to 30 mm.

[0089] Generally, the aqueous depolymerization mixture according to (ii) can be prepared by any method. Preferably, the preparation of the aqueous depolymerization mixture includes melting in a melting unit U. M In the molten solid material M, the pressure p is obtained. SM Below has temperature T SM Liquid flow S M In the pre-reaction unit U PR Lieutenant General S M With pressure p SW Below has temperature T SW Water flow S W Mixing, obtaining under pressure p SF Below has temperature T SF Liquid reaction feed stream S F ; will be based on the obtained stream S F This depolymerization mixture is fed into chemical reaction unit U. R In terms of the design of this method, the preferred option is...

[0090] 0.8 ≤ T SF / T D ≤ 1.05 and 0.9 ≤ p SF / p D ≤ 1.05;

[0091] 0.6 ≤ T SM / T SF ≤ 1.2 and 0.9 ≤ p SM / p SF ≤ 1.05; and

[0092] 0.8 ≤ T SW / T SF≤ 1.2 and 0.9 ≤ p SW / p SF ≤ 1.05;

[0093] Among them, the reaction unit U R The depolymerization conditions of polyamide 6 include T D It is the depolymerization temperature and p D It is the pressure to depolymerize.

[0094] Pre-reaction unit U PR Preferably, it includes a mixing unit, preferably a static mixing unit, more preferably composed of the latter, and wherein the melting unit U M This includes an extruder, preferably a single-screw extruder or a twin-screw extruder, and is preferably composed of such extruders. Further, it is preferred that S... W and S M A mixing ratio (m) in the range of 1:1 to 20:1, more preferably in the range of 2:1 to 15:1, and even more preferably in the range of 5:1 to 10:1. W / kg) / (m P / kg) in U PR Mixed in, where m W It is S W The amount of water contained in it, and m P It is S M The amount of polyamide 6 contained therein.

[0095] With respect to the hydrolysis and depolymerization according to the present invention, it is preferred that unit U R The depolymerization pressure p in D Within the range of 40 to 140 bar, more preferably within the range of 40 to 125 bar, and even more preferably within the range of 40 to 110 bar; and unit U R The depolymerization temperature T in D The temperature ranges from 230°C to 335°C, more preferably from 250°C to 320°C, and even more preferably from 270°C to 310°C.

[0096] Preferably, reaction unit U R Includes z chemical reactors R i , i = 1…z, where z is in the range of 1 to 10, preferably in the range of 1 to 8, more preferably in the range of 1 to 6, more preferably in the range of 1 to 5, more preferably in the range of 1 to 4, and more preferably in the range of 1 to 3. If z > 1, then it is preferred to have at least 2 reactors R. i More preferably, all z reactors R i They are connected in series, where

[0097] - This stream S F Feeding to R i In the case of i, where i = 1;

[0098] - Aqueous liquid containing dissolved ε-caprolactam S i From reactor R i Remove from the middle and feed into reactor R i+1 In the case of z, i < z;

[0099] - The aqueous liquid containing ε-caprolactam dissolved in water is flowed into the S stream. z As flow S R From reactor R z Remove from the middle;

[0100] In each reactor R i In the middle, under the depolymerization pressure p Di Maintain depolymerization temperature T Di , among which, independently of each other, T Di Within the range of 230°C to 330°C and p Di Within the range of 40 to 140 bar, preferably where T Di Within the range of 250°C to 320°C and p Di In the range of 40 to 125 bar, more preferably, T Di Within the range of 270°C to 310°C and p Di Within the range of 40 to 110 bar. For z > 1, z reactors R are preferred. i Arranged vertically, with R1 being the topmost reactor and R... z It is the bottom reactor, from which R i S obtained i Transferred to R by gravity, preferably solely by gravity. i+1 More preferably, at least one, and preferably all z, reactors R i It is a continuous stirred tank reactor (CSTR). Preferably, each continuous stirred tank reactor R i The reactor R has 2 to 6 compartments, more preferably 2 to 5 compartments, and even more preferably 2 to 4 compartments, which are independently arranged. These compartments are preferably connected in series, more preferably connected in series and arranged vertically, wherein two adjacent compartments are separated by a partition that includes at least one flow opening. Preferably, the reactor R... i The reactor includes at least one compartment comprising at least one agitator, wherein more preferably each reactor R i Each compartment includes at least one agitator, wherein more preferably, each reactor R iEach compartment includes an agitator, and the method includes agitating the depolymerization mixture in a given compartment for at least a portion of the time during which the depolymerization conditions are subjected in the compartment. Preferably, the polyamide 6 depolymerization conditions further include an aqueous depolymerization mixture in unit U. R In the middle, preferably in z reactors R i The more preferred total residence time t in z continuous stirred tank reactors D The aqueous depolymerization mixture contains at least 85% by weight, preferably at least 90% by weight, more preferably at least 95% by weight, having a t in the range of 30 to 90 min. D More preferably, the aqueous depolymerization mixture in reactor R i The dwell time in is t Di And 0.90 ≤ (t) Di / t Di+1 ) ≤ 1.10, more preferably 0.95 ≤ (t Di / t Di+1 ) ≤ 1.05.

[0101] If the solid material M comprises one or more polyurethane elastic fibers, then a self-depolymerizing aqueous liquid flow S is obtained. R It typically contains one or more decomposition products formed from one or more polyurethane elastic fibers, such as in U R In the depolymerization process. Alternatively or alternatively, one or more decomposition products from the one or more polyurethane elastic fibers may also be present in the melting unit U described above. M Formed in the process. As an example, the one or more decomposition products from one or more polyurethane elastic fibers preferably include at least one of the following: aniline, butanediol, butanediol oligomers (including, for example, butanediol dimers and butanediol trimers), and 4,4'-methylenediphenylamine (MDA) and its isomers such as 2,4'-methylenediphenylamine and 2,2'-methylenediphenylamine.

[0102] According to the present invention, it is preferred that the flow S according to (iii) is prepared in the hydrolysis-depolymerization reaction. R The process is carried out in the absence of a polyamide 6 depolymerization catalyst such as an inorganic acid and / or a zinc salt such as zinc chloride, zinc acetate, or zinc trifluoromethanesulfonate, i.e., the preparation is not carried out using such a polyamide 6 depolymerization catalyst or the depolymerization mixture to be subjected to depolymerization conditions does not contain such a depolymerization catalyst.

[0103] Typically, the method of this invention can be designed as a continuous method, a semi-continuous method, or a batch method.

[0104] As described above, the mixture M of the present invention has a certain minimum water content. FIt is suitable for storage and retains its advantageous characteristics even after storage, particularly in terms of its APHA color. Therefore, the method of the present invention may further include...

[0105] (v) The mixture M obtained according to (iv) F The mixture was stored in an inert gas atmosphere at a temperature of up to 80°C for a duration Δt. Σ Obtain the stored mixture M S The storage time Δt Σ It is at least 1 day.

[0106] Preferably, according to (v), mixture M F It is stored away from light. More preferably, according to (v), the storage time Δt Σ The inert gas atmosphere is at least 7 days, more preferably at least 14 days, and even more preferably in the range of 14 to 28 days. Further preferably, according to (v), the inert gas atmosphere comprises one or more of nitrogen and argon. Further according to the invention, it is preferred that the mixture M... F According to (v) in the mixture M F The storage temperature δ is in the range of 20°C to 80°C, preferably in the range of 25°C to 80°C, more preferably in the range of 35°C to 77°C, and even more preferably in the range of 50°C to 75°C. S Storage below. Further according to the invention, preferably, the mixture M is... F The storage pressure p of the inert gas atmosphere is in the range of 0.5 to 10 bar, more preferably in the range of 0.75 to 5 bar, and even more preferably in the range of 1 to 2 bar. S Storage. Further according to the invention, preferably, storage according to (v) includes agitation, preferably mechanical agitation, more preferably stirring of the mixture M. F Continuous storage time Δt Σ At least a portion thereof, preferably lasting substantially the entire storage time Δt Σ .

[0107] Further findings revealed that, in the case of mixture M F Storage at a temperature where the water content has a specific functional relationship with the temperature according to (v) may be advantageous. Specifically, it may be preferred that...

[0108] During storage according to (v),

[0109] (δ S / °C) = -2.6 • (x H2O (M F ) / weight-%) + C S

[0110] Where C S = 77 ± 10, preferably C S = 77 ± 5.

[0111] Furthermore, the present invention also relates to a storage mixture M F The method involves a mixture containing ε-caprolactam and water and having a purity of at least 99% Ω. GC (M F APHA value of up to 20 Ω APHA (M F ) and based on the mixture M F The total weight must be at least 0.1 wt% water content x H2O (M F The method includes mixing the mixture M F The mixture was stored in an inert gas atmosphere at a temperature of up to 80°C for a duration Δt. Σ Obtain the stored mixture M S The storage time Δt Σ It is at least 1 day.

[0112] With regard to the storage method, preferably, a mixture M comprising at least 99 wt%, preferably at least 99.1 wt%, more preferably at least 99.2 wt%, more preferably at least 99.3 wt%, more preferably at least 99.4 wt%, more preferably at least 99.5 wt%, more preferably at least 99.6 wt%, more preferably at least 99.7 wt%, more preferably at least 99.8 wt%, and more preferably at least 99.9 wt%. F It is composed of ε-caprolactam and water.

[0113] Preferably, in terms of storage method, Ω GC (M F The content is at least 99.5%, more preferably at least 99.6%, more preferably at least 99.7%, more preferably at least 99.8%, and more preferably at least 99.9%. Further, preferably, Ω APHA (M F The value is at most 15, more preferably at most 12.5, more preferably at most 10, more preferably at most 7.5, and more preferably at most 5. Furthermore, it is preferred that x H2O (M F The content is in the range of 0.1 to 10 wt%, more preferably in the range of 0.15 to 9 wt%, more preferably in the range of 0.2 to 8 wt%, more preferably in the range of 0.35 to 7 wt%, and more preferably in the range of 0.5 to 6 wt%.H2O (M F Suitable ranges for M may include 0.5 to 2 wt%, 2 to 4 wt%, and 4 to 6 wt%. Therefore, such a mixture M F It is more preferred, where Ω GC (M F It is at least 99.9%, Ω APHA (M F It is at most 5%, and x H2O (M F (In the range of 0.5 to 6% by weight)

[0114] Optionally or preferably, in terms of storage method, mixture M F A further characteristic is that the permanganate absorbance number Ω PAN (M F ) and UV absorbance Ω UV (M F One or more of the following: Ω PAN (M F Preferably, the number is at most 20, more preferably at most 15, and even more preferably at most 10. Ω UV (M F Preferably, it is at most 0.75, more preferably at most 0.25, and even more preferably at most 0.1. Therefore, such a mixture M... F It is more preferred, where Ω PAN (M F It is at most 10 and Ω UV (M F The concentration is at most 0.1. Therefore, a mixture M is more preferably such that... F , where Ω GC (M F It is at least 99.9%, Ω APHA (M F It is at most 5, x H2O (M F Ω is in the range of 0.5 to 6 wt%. PAN (M F It is at most 10 and Ω UV (M F The value is at most 0.1.

[0115] Preferably, in terms of storage method, mixture M F It can be obtained or acquired by means including steps (i) to (iv) as described above.

[0116] Further regarding the storage method, it is preferred that the mixture M FIt is stored away from light. More preferably, regarding the storage method, the storage time Δt... Σ The storage period is at least 7 days, more preferably at least 14 days, and more preferably in the range of 14 to 28 days. Furthermore, regarding the storage method, the inert gas atmosphere includes one or more of nitrogen and argon. More preferably, regarding the storage method, mixture M... F In the mixture M F The storage temperature δ is in the range of 20°C to 80°C, preferably in the range of 25°C to 80°C, more preferably in the range of 35°C to 77°C, and even more preferably in the range of 50°C to 75°C. S Storage. More preferably, regarding the storage method, the mixture M... F The storage pressure p of the inert gas atmosphere is in the range of 0.5 to 10 bar, more preferably in the range of 0.75 to 5 bar, and even more preferably in the range of 1 to 2 bar. S Storage. Further preferably, regarding the storage method, it is preferred that the storage according to (v) includes agitation, preferably mechanical agitation, more preferably stirring of the mixture M. F Continuous storage time Δt Σ At least a portion thereof, preferably lasting substantially the entire storage time Δt Σ .

[0117] Further findings revealed that, in the case of mixture M F Storage methods that allow the water content to have a specific functional relationship with the storage temperature may be advantageous. Specifically, it is preferable that, during storage,

[0118] (δ S / °C) = -2.6 • (x H2O (M F ) / weight-%) + C S

[0119] Where C S = 77 ± 10, preferably C S = 77 ± 5.

[0120] Typically, in the context of this invention, the value Ω(M) F (e.g., Ω) GC (M F ) and Ω APHA (M F )) refers to something that is basically immediately following the mixture M F The corresponding value Ω (M) after preparation F ), especially the corresponding value Ω (M) before storage. F ).

[0121] The present invention also relates generally to a liquid mixture M F It contains ε-caprolactam and water and has a purity of at least 99% Ω. GC (M F APHA value of up to 20 Ω APHA (M F ) and based on the mixture M F The total weight must be at least 0.1 wt% water content x H2O (M F The mixture M F The mixture M is preferably obtained or acquired by a method comprising steps (i) to (iv) as described above. F It exhibits storage stability Σ after storage time Δt. Δt , where Σ Δt From APHA value Ω APHA (Δt) characterization.

[0122] If Δt is 14 days and the storage stability Σ is after the storage time 14 From APHA value Ω APHA (14) Characterization, then the preferred one is

[0123] -If Ω APHA (M F If it is less than 5, then Ω APHA (14) ≤ 10;

[0124] -If Ω APHA (M F If Ω is in the range of 5 to 8, then APHA (14) ≤ 2 Ω APHA (M F );

[0125] -If Ω APHA (M F If ) > 8, then Ω APHA (14) ≤ 1.5 Ω APHA (M F )).

[0126] If Δt is 28 days and the storage stability Σ is after the storage time 28 From APHA value Ω APHA (28) Characterization, then the preferred one is

[0127] -If Ω APHA (M F If it is less than 4, then Ω APHA (28) ≤ 10;

[0128] -If Ω APHA (M F If the value is in the range of 4 to 8, then Ω APHA (28) ≤ 3 Ω APHA (M F );

[0129] -If Ω APHA (M F If ) > 8, then Ω APHA (28) ≤ 2 Ω APHA (M F ).

[0130] Further according to the present invention, the storage stability Σ after storage time Δt Δt It can be further absorbed by permanganate in Ω. PAN (Δt) and UV absorbance Ω UV One or more of the characteristics in (Δt).

[0131] If Δt is 14 days and the storage stability Σ is after the storage time 14 Absorbance of permanganate Ω PAN (14) and UV absorbance Ω UV If one or more of the characteristics in (14) are preferred, then the preferred one is...

[0132] -If Ω PAN (M F If it is less than 5, then Ω PAN (14) ≤ 10;

[0133] -If Ω PAN (M F If Ω is in the range of 5 to 8, then PAN (14) ≤ 1.5 Ω PAN (M F );

[0134] -If Ω PAN (M F If ) > 8, then Ω PAN (14) ≤ 1.25 Ω PAN (M F );

[0135] and

[0136] -If Ω UV (M F If it is less than 0.02, then Ω UV (14) ≤ 0.05;

[0137] -If Ω UV (MF If Ω is in the range of 0.02 to 0.03, then UV (14) ≤ 3 Ω UV (M F );

[0138] -If Ω UV (M F If ) > 0.03, then Ω UV (14) ≤ 1.25 Ω UV (M F ).

[0139] If Δt is 28 days and the storage stability Σ is after the storage time 28 Absorbance of permanganate Ω PAN (28) and UV absorbance Ω UV If one or more of the characteristics in (28) are preferred, then the preferred one is...

[0140] -If Ω PAN (M F If it is less than 5, then Ω PAN (28) ≤ 10;

[0141] -If Ω PAN (M F If Ω is in the range of 5 to 8, then PAN (28) ≤ 3 Ω PAN (M F );

[0142] -If Ω PAN (M F If ) > 8, then Ω PAN (28) ≤ 2 Ω PAN (M F );

[0143] and

[0144] -If Ω UV (M F If it is less than 0.025, then Ω UV (28) ≤ 0.05;

[0145] -If Ω UV (M F If Ω is in the range of 0.025 to 0.05, then UV (28) ≤ 3 Ω UV (M F );

[0146] -If Ω UV (M F If ) > 0.05, then ΩUV (28) ≤ 2 Ω UV (M F ).

[0147] The present invention also relates generally to a stored liquid mixture M S It contains ε-caprolactam and water, wherein the mixture M S It can be obtained or acquired by the method including step (v) as described above.

[0148] For the stored mixture M S Preferably, the stored mixture exhibits an APHA value Ω after a storage time of 14 days Δt. APHA (14), of which

[0149] -If Ω APHA (M F If it is less than 4, then Ω APHA (14) ≤ 10;

[0150] -If Ω APHA (M F If the value is in the range of 4 to 8, then Ω APHA (14) ≤ 2 Ω APHA (M F );

[0151] -If Ω APHA (M F If ) > 8, then Ω APHA (14) ≤ 1.5 Ω APHA (M F ).

[0152] For the stored mixture M S Further preferably, the stored mixture exhibits an APHA value Ω after a storage time of 28 days Δt. APHA (28), of which

[0153] -If Ω APHA (M F If it is less than 4, then Ω APHA (28) ≤ 10;

[0154] -If Ω APHA (M F If the value is in the range of 4 to 8, then Ω APHA (28) ≤ 3 Ω APHA (M F );

[0155] -If Ω APHA (M F If ) > 8, then ΩAPHA (28) ≤ 2 Ω APHA (M F ).

[0156] The stored mixture M S The characteristic can be further described by the permanganate absorbance number Ω PAN (Δt) and UV absorbance Ω UV One or more of (Δt).

[0157] If the storage time Δt is 14 days, then for mixture M S The preferred option is

[0158] -If Ω PAN (M F If it is less than 5, then Ω PAN (14) ≤ 10;

[0159] -If Ω PAN (M F If Ω is in the range of 5 to 8, then PAN (14) ≤ 1.5 Ω PAN (M F );

[0160] -If Ω PAN (M F If ) > 8, then Ω PAN (14) ≤ 1.25 Ω PAN (M F );

[0161] and

[0162] -If Ω UV (M F If it is less than 0.01, then Ω UV (14) ≤ 0.05;

[0163] -If Ω UV (M F If Ω is in the range of 0.01 to 0.03, then UV (14) ≤ 3 Ω UV (M F );

[0164] -If Ω UV (M F If ) > 0.03, then Ω UV (14) ≤ 1.25 Ω UV (M F ).

[0165] If the storage time Δt is 28 days, then for mixture MS The preferred option is

[0166] -If Ω PAN (M F If it is less than 5, then Ω PAN (28) ≤ 10;

[0167] -If Ω PAN (M F If Ω is in the range of 5 to 8, then PAN (28) ≤ 3 Ω PAN (M F );

[0168] -If Ω PAN (M F If ) > 8, then Ω PAN (28) ≤ 2 Ω PAN (M F );

[0169] and

[0170] -If Ω UV (M F If it is less than 0.025, then Ω UV (28) ≤ 0.05;

[0171] -If Ω UV (M F If Ω is in the range of 0.025 to 0.04, then UV (28) ≤ 1.5 Ω UV (M F );

[0172] -If Ω UV (M F If ) > 0.03, then Ω UV (28) ≤ 1.25 Ω UV (M F ).

[0173] The present invention further relates to the mixture M as described above. F and / or mixtures M as described above S Used as a material for chemical processes, preferably for polymerization reactions, and more preferably for the preparation of polyamide 6 precipitates.

[0174] The present invention further relates to a method for preparing polyamide 6, the method comprising:

[0175] (A) Prepare mixture M according to the method described above, including steps (i) to (iv). F and / or provide the mixture M as described aboveF ;

[0176] (B) Optionally, the mixture M F The mixture M is stored under the storage conditions defined above in the context of method step (v) to obtain the stored mixture. S ;

[0177] (C) To make the mixture M prepared and / or provided according to (A) F And / or the mixture M according to (B) S It was subjected to the polymerization conditions of polyamide 6.

[0178] The present invention further relates to polyamide 6 itself, which can be obtained or acquired by the method, wherein the polyamide has an nAPHA value of up to 10, preferably up to 9, more preferably up to 8.

[0179] The present invention further relates to a method as described above, the method comprising mixing M F M at least a portion or mixture S At least a portion is supplied to polyamide 6 production unit U PP Among them, in U PP Polyamide 6 produced in the process is preferably supplied as a raw material to textile material production unit U. TP From this unit U TP middle

[0180] (A) Obtaining textile materials M for market launch TE In the textile material M TE Lifespan T MTE Subsequently, it is collected, at least partially, as textile waste in textile material collection unit U. TC middle;

[0181] (B) Obtain the remaining material M RE As textile waste;

[0182] At least a portion of the textile waste according to (A), or at least a portion of the textile waste according to (B), or at least a portion of the textile waste according to (A) and at least a portion of the textile waste according to (B) shall be suitably provided as material M according to (i).

[0183] The present invention further relates to a method as described above, the method comprising mixing M F M at least a portion or mixture S At least a portion is supplied to polyamide 6 production unit U PP Among them, in U PPPolyamide 6 produced in the process is preferably supplied as a raw material to the engineering plastics production unit U. EP From this unit U EP middle

[0184] (A) Obtaining engineering plastic materials M for market launch EP In the engineering plastic material M EP Lifespan T MEP Subsequently, it is collected, at least partially, as engineering plastic waste in the engineering plastics material collection unit U. EC middle;

[0185] (B) Obtain the remaining material M RE As engineering plastic waste;

[0186] At least a portion of the engineering plastic waste according to (A), or at least a portion of the engineering plastic waste according to (B), or at least a portion of the engineering plastic waste according to (A) and at least a portion of the engineering plastic waste according to (B) shall be suitably provided as material M according to (i).

[0187] The present invention further relates to the mixture M as described above. F Or a mixture M as described above S Uses for preparing polyamide 6, wherein the uses preferably further include using the polyamide 6 as a raw material for preparing one or more textile materials and engineering plastic materials, more preferably for preparing textile materials.

[0188] The present invention further relates to a method for preparing polyamide 6, the method comprising using a mixture M as described above. F Or a mixture M as described above S As a starting material, the method preferably further includes using the polyamide 6 as one or more of textile materials and engineering plastic materials, more preferably as a raw material for preparing textile materials.

[0189] The present invention further relates to the mixture M as described above. F Or a mixture M as described above S Used for preparing one or more polymers and polymer products; or a method for preparing one or more polymers and polymer products, said method comprising using a mixture M as described above. F Or a mixture M as described above S As starting material.

[0190] Preferably, according to the use or method described above, the polymer, or polymer product, or polymer and polymer product are in the form of at least one of particles, strands, rods, plates, tubes, foils, layers, films, sheets, fibers, filaments, coatings, extruded articles, molded articles, soft foams, semi-rigid foams and rigid foams.

[0191] Further preferably, according to the uses or methods described above, the polymer, or polymer product, or polymer and polymer product comprises polyamide 6 and optionally at least one other polymer compound, said polyamide 6 being at least partially composed of the mixture M as described above. F Or a mixture M as described above S Available or obtainable, wherein the at least one additional polymer compound preferably includes one or more of the following: at least one polyamide 6.6, at least one polyethylene terephthalate, at least one polyurethane, at least one polyester, at least one cellulose material, and at least one rubber material (including one or more of at least one natural rubber material and at least one synthetic rubber material).

[0192] More preferably, according to the uses or methods described above, the polymer, or polymer product, or polymer and polymer product is one or a portion of the following:

[0193] - Automotive parts, preferably cylinder head covers, engine covers, housings for turbocharged air coolers, turbocharged air cooler baffles, intake pipes, intake manifolds, connectors, gears, fan impellers, coolant tanks, housings or housing parts for heat exchangers, coolant coolers, turbocharged air coolers, thermostats, water pumps, radiators, fasteners for electric vehicles or battery system parts, dashboards, steering column switches, seats, headrests, center consoles, transmission components, door modules, automotive exterior trim for A-pillar, B-pillar, C-pillar or D-pillar covers, spoilers, door handles, exterior mirrors, windshield wipers, windshield wiper protective housings, decorative grilles, cover strips, roof racks, window frames, sunroof frames, antenna panels, headlights, taillights, airbags, roof mats, oil pans, fuel cells, heat shields and / or seat cushions;

[0194] - Fabrics, clothing, preferably shirts, trousers, sweaters, boots, shoes, soles, tights, yarns, fabrics and / or jackets;

[0195] - Electrical components, preferably electrical parts, passive electronic parts, active electronic parts, printed circuit boards, housing parts, foils, circuits, switches (such as microswitches), plugs, sockets, distributors, relays, resistors, capacitors, inductors, spools, lamps, diodes (such as LEDs), transistors, connectors, regulators, integrated circuits (ICs), processors, controllers, memories, sensors, microbuttons, semiconductors, such as reflector housings for light-emitting diodes, fasteners for electrical and / or electronic components, spacers, bolts, strips, slide rails, screws, nuts, membrane hinges, snap hooks (buckles) and / or spring tongues;

[0196] - Consumer goods and / or pharmaceutical products, preferably tennis strings, climbing ropes, bristles, brushes, artificial turf, 3D printed filaments, lawnmowers, zippers, Velcro, paper machine netting, extrusion coatings, fishing lines, fishing nets, marine pipelines and ropes, vials, syringes, ampoules, bottles, sliding elements, spindle nuts, chain conveyors, sliding bearings, rollers, wheels, gears, ring gears, screws and spring dampers, hoses, pipes, cable sheaths, sockets, switches, cable ties, fan impellers, carpets, boxes and / or bottles for cosmetics, mattresses, cushions, and insulating materials;

[0197] - Packaging for the food industry, preferably single-layer and / or multi-layer blown film, cast film (single-layer and / or multi-layer), biaxial stretch film, or laminated film.

[0198] More preferably, according to the uses or methods described above, the polymer, or polymer product, or polymer and polymer product contains polyamide 6, which is composed of the mixture M as described above. F Or a mixture M as described above S It may be obtained or acquired in an amount of 1 wt% or more, preferably 2 wt% or more, more preferably 5 wt% or more, more preferably 15 wt% or more, more preferably 30 wt% or more, more preferably 40 wt% or more, more preferably 60 wt% or more, more preferably 80 wt% or more, more preferably 90 wt% or more, more preferably 95 wt% or more; and / or in an amount of 100 wt% or less, preferably 95 wt% or less, more preferably 90 wt% or less, more preferably 50 wt% or less, more preferably 25 wt% or less, more preferably 10 wt% or less.

[0199] The invention is further illustrated by the following set of embodiments and combinations of embodiments derived from the dependent relationships and reverse references shown. In particular, it should be noted that in each instance of reference to a series of embodiments, such as in the context of the term "method as described in any one of Embodiments 1 to 4," each embodiment in this series is intended to clearly disclose to those skilled in the art that the wording of this term should be understood by those skilled in the art to be synonymous with "method as described in any one of Embodiments 1, 2, 3, and 4." Furthermore, it should be clearly noted that the following set of embodiments represents appropriate structural portions of the general description of preferred aspects of the invention and therefore appropriately supports, but does not represent, the claims of the invention.

[0200] 1. A method for preparing liquid ε-caprolactam mixtures M F The method includes

[0201] (i) Provide stream S M The stream contains a solid material M containing polyamide 6;

[0202] (ii) Preparation based on S M Aqueous depolymerization mixtures;

[0203] (iii) The depolymerized mixture prepared according to (ii) is reacted in reaction unit U R The polyamide 6 was subjected to depolymerization conditions to obtain a product containing polyamide 6 at a concentration of c. SR Liquid aqueous flow S of ε-caprolactam dissolved in water R The stream S R It further contains one or more impurities; and optionally the liquid aqueous stream S R Transferred to evaporation unit U E In the middle, by S R Obtain the concentration c SL Liquid aqueous flow S of ε-caprolactam dissolved in water L , where c SL > c SR And further by S R Obtain one or more water vapor streams S V ;

[0204] (iv) The stream S R Optionally, this stream S L Transferred to ε-caprolactam purification unit U P In the middle, and

[0205] (iv.1) From this unit U P To obtain the mixture M F ;or

[0206] (iv.2) From this unit U PObtain mixture M T The mixture has at least 99% ε-caprolactam purity Ω GC (M T APHA value of up to 20 Ω APHA (M T ) and based on the mixture M T Total weight at most 0.05% by weight of water content x H2O (M T ), and to the mixture M T Add water to obtain mixture M. F ;

[0207] Wherein the mixture M F It has at least 99% purity of ε-caprolactam Ω GC (M F APHA value of up to 20 Ω APHA (M F ) and based on the mixture M F The total weight must be at least 0.1 wt% water content x H2O (M F ).

[0208] 2. The method as described in Example 1, wherein Ω GC (M F It is at least 99.5%, more preferably at least 99.8%, and more preferably at least 99.9%.

[0209] 3. The method as described in Example 1 or 2, wherein Ω APHA (M F The value is at most 15, preferably at most 10, and more preferably at most 5.

[0210] 4. The method as described in any one of Examples 1 to 3, wherein the mixture M F It has a temperature in the range of 20°C to 80°C, preferably in the range of 35°C to 77°C, and more preferably in the range of 50°C to 75°C.

[0211] 5. The method as described in any one of Examples 1 to 4, wherein x H2O (M F The content is in the range of 0.1 to 10 wt%, preferably in the range of 0.2 to 8 wt%, and more preferably in the range of 0.5 to 6 wt%.

[0212] 6. The method as described in any one of Examples 1 to 5, wherein the mixture M F A further characteristic is that the permanganate absorbance number Ω PAN (M F) and UV absorbance Ω UV (M F One or more of ) where Ω PAN (M F The value is at most 20, preferably at most 15, more preferably at most 10, and wherein Ω UV (M F The value is at most 0.75, preferably at most 0.25, and more preferably at most 0.1.

[0213] 7. The method as described in any one of Examples 1 to 6, wherein the purification unit U according to (v) P Including water separation unit U WS and distillation unit U D The method preferably includes placing the stream S R Optionally, this stream S L Feed to U WS From U WS Obtain the concentration c UWS The flow of ε-caprolactam S UWS , will the stream S UWS Feed into the distillation unit U D From U D Obtain the concentration c MF The mixture M of ε-caprolactam F , where c SR < c UWS <<< c MF Preferably, where c SL < c UWS <<< c MF .

[0214] 8. The method as described in Example 7, wherein the water separation unit U WS Includes at least two water ion units U WS1 and U WS2 Preferably, two water ion units U connected in series WS1 and U WS2 , where the stream S R Optionally, this stream S L Feed into U WS1 In, among them in U WS1 Downstream and in U WS2 Upstream, a separation unit U is preferably provided. I The method includes from U WS1 Obtaining water flow S UWS1 , will the stream S UWS1 Feed into the separation unit U I In the middle, from U I Obtaining water flow SUI and the stream S UI Feeding into unit U WS2 In, among them in U I In the middle, from S UWS1 One or more impurities can be separated from U, thereby separating them from U. I Obtain impurity flow S I The impurity preferably comprises at least one of the impurities contained in S according to (iii). R Impurities in the separation unit U, wherein at least one of the impurities is an organic compound having a higher boiling point than ε-caprolactam. I It is a high-boiling-point separation unit.

[0215] 9. The method as described in Example 7 or 8, wherein the purification unit U P In this unit U D The downstream of the crystallization unit U CR and chemical processing unit U OD One or more of them, the method includes from U CR China or from U OD To obtain the mixture M F .

[0216] 10. The method as described in Example 9, wherein the unit U OD Chemical treatments include

[0217] (a) Provide from this distillation unit U D The preferred liquid flow S containing ε-caprolactam UD Or from this crystallization unit U CR The preferred liquid flow S containing ε-caprolactam CR The flow S UD or the flow S CR Further comprising one or more oxidizable organic impurity compounds X, wherein the stream S UD Or the stream S CR It has at least 99% purity of ε-caprolactam Ω GC (S C And it shows the weight ratio r of one or more organic compounds X relative to ε-caprolactam. XC ;

[0218] (b) Providing a flow containing at least one permanganate S O ;

[0219] (c) From this flow S UD and the S stream O Or by the flow S SCR and the S stream O Preparation of Oxidation Reaction Separate Mixture MOE And make the mixture M OE Under oxidative reaction conditions, an oxidation product stream S containing ε-caprolactam was obtained. P The oxidation product stream further comprises one or more oxidation products Y obtained by oxidation of at least a portion of the one or more compounds X, and optionally further comprises a portion of the one or more organic compounds X, wherein the stream S P The weight ratio r of organic compound X relative to ε-caprolactam is shown. XCP , where 0 ≤ r XCP < r XC Furthermore, it demonstrates the weight ratio r of one or more products Y relative to ε-caprolactam. YCP , where r YCP > 0;

[0220] (d) From the stream S P The mixture M is obtained by separating at least a portion of one or more oxidation products Y and optionally at least a portion of organic compound X. F Or the mixture M T It exhibits a weight ratio r of oxidation product Y to ε-caprolactam. YCT , where 0 ≤ r YCT < r YCP Furthermore, it demonstrates the weight ratio r of organic compound X relative to ε-caprolactam. XCT , where 0 ≤ r XCT < r XC .

[0221] 11. The method as described in Example 10, wherein the stream S provided according to (b) is included O The at least one permanganate in the formula includes at least an alkali metal permanganate, preferably composed of the alkali metal permanganate, and more preferably, the at least one alkali metal permanganate includes one or more of sodium permanganate and potassium permanganate.

[0222] 12. The method as described in Example 10 or 11, wherein 0.5 to 100 wt% of the stream S provided according to (b) O It is composed of permanganate.

[0223] 13. The method as described in any one of Examples 10 to 12, wherein the stream S provided according to (b) O It further includes water.

[0224] 14. The method as described in any one of Examples 10 to 13, wherein the oxidation reaction precipitate mixture M prepared according to (c) OEIt exhibits a permanganate concentration calculated as MnO4 in the range of 0.005 to 5 wt%, preferably in the range of 0.01 to 3 wt%, and more preferably in the range of 0.05 to 1 wt%.

[0225] 15. The method as described in any one of Examples 10 to 14, wherein the oxidation reaction conditions according to (c) include the mixture M OE Temperature T in the range of 40°C to 140°C, preferably in the range of 60°C to 100°C, and more preferably in the range of 70°C to 90°C OE .

[0226] 16. The method as described in any one of Examples 10 to 15, wherein the mixture M prepared according to (c) OE It further includes water.

[0227] 17. The method as described in any one of Examples 10 to 16, wherein the mixture M is made OE Subjected to oxidation reaction conditions in the chemical processing unit U OD The oxidation reaction unit U in OR The process is carried out in which the unit U OR Preferably, it includes one or more of at least one continuous stirred tank reactor and at least one tubular reactor.

[0228] 18. The method as described in any one of Examples 10 to 17, further comprising providing a stream S containing at least one hydroxide. B The mixture M of the oxidative reaction product according to (c) OE From this flow S UD Or the stream S CR and by the flow S O and the S stream B preparation.

[0229] 19. The method as described in Example 18, wherein the stream S contains B The at least one hydroxide in the form includes at least an alkali metal hydroxide, preferably composed of the same, and more preferably, the at least one alkali metal hydroxide includes sodium hydroxide, more preferably composed of the same.

[0230] 20. The method as described in Example 18 or 19, wherein 0.5 to 100 wt% of the stream S B It is composed of hydroxides.

[0231] 21. The method as described in any one of Examples 18 to 20, wherein the flow S B It further includes water.

[0232] 22. The method as described in any one of Examples 18 to 21, wherein the oxidation reaction precipitate mixture M prepared according to (c) OE It exhibits a hydroxide concentration, calculated in OH, in the range of 0.005 to 0.75 wt%, preferably in the range of 0.01 to 0.5 wt%, and more preferably in the range of 0.1 to 0.25 wt%.

[0233] 23. The method as described in any one of Examples 10 to 22, wherein the one or more oxidizable organic compounds X have a boiling point δ. X / °C, where 0.5 ≤ (δ X / δ C ) ≤ 1.5, δ C / °C is the boiling point of ε-caprolactam, and at least one of the one or more oxidation products Y has a boiling point δ. Y / °C, where δ Y / °C ≠ δ C / °C, where the boiling point δ Y With boiling point δ C The temperature difference Δδ is preferably at least 1°C.

[0234] 24. The method as described in any one of Examples 10 to 23, wherein, according to (d) from the stream S P Separating at least a portion of the one or more oxidation products Y and optionally at least a portion of the organic compound X from the stream S obtained according to (c) comprises making the stream S... P Including the chemical processing unit U OD Distillation unit U in DT The middle undergoes distillation, from the distillation unit U DT To obtain as the mixture M F Or the mixture M T Stream S containing ε-caprolactam DT The unit U DT It includes one or more distillation columns, preferably one or two distillation columns, wherein at least one column is optionally configured as a side-flow column or a split-wall column.

[0235] 25. The method as described in any one of Examples 10 to 24, wherein, prior to undergoing separation according to (d), the stream S obtained from (c) is... P Filtered.

[0236] 26. The method as described in any one of Examples 9 to 25, wherein the purification unit U P Further includes crystallization unit U CR The method includes distilling from the distillation unit U D Obtain the concentration cUD The flow of ε-caprolactam S UD and the stream S UD Feed into the crystallization unit U CR From U CR Obtain the concentration c MF The mixture M of ε-caprolactam F .

[0237] 27. The method as described in any one of Examples 9 to 25, wherein the purification unit U P Further includes chemical processing unit U OD The method includes distilling from the distillation unit U D Obtain the concentration c UD The flow of ε-caprolactam S UD and the stream S UD Feed into the chemical processing unit U OD From U OD Obtain the concentration c MF The mixture M of ε-caprolactam F .

[0238] 28. The method as described in any one of Examples 9 to 25, wherein the purification unit U P Further includes chemical processing unit U OD and crystallization unit U CR The crystallization unit U CR Located in the distillation unit U D Downstream of, and the chemical processing unit U OD Located in the crystallization unit U CR Downstream of the distillation unit U, the method includes... D Obtain the concentration c UD The flow of ε-caprolactam S UD , will the stream S UD Feed into the crystallization unit U CR From this crystal U CR Obtain the concentration c CR The flow of ε-caprolactam S CR and the stream S CR Feed into the chemical processing unit U OD From U OD Obtain the concentration c MF The mixture M of ε-caprolactam F .

[0239] 29. The method as described in any one of Examples 9 to 25, wherein the purification unit U P Further includes chemical processing unit U OD and crystallization unit UCR The chemical processing unit U OD Located in the distillation unit U D Downstream of, and the crystallization unit U CR Located in unit U CR Downstream of the distillation unit U, the method includes... D Obtain the concentration c UD The flow of ε-caprolactam S UD , will the stream S UD Feed into the chemical processing unit U OD From the chemical processing unit U OD Obtain the concentration c OD The flow of ε-caprolactam S OD and the stream S OD Feed into the crystallization unit U CR From U CR Obtain the concentration c MF The mixture M of ε-caprolactam F .

[0240] 30. The method as described in any one of Examples 1 to 29, wherein x H2O (M T The content is in the range of 0 to 0.05% by weight, preferably in the range of 0 to 0.01% by weight, and more preferably in the range of 0 to 0.001% by weight.

[0241] 31. The method as described in any one of Examples 1 or 30, wherein Ω GC (M T It is at least 99.5%, preferably at least 99.8%, and more preferably at least 99.9%.

[0242] 32. The method as described in any one of Examples 1 to 31, wherein Ω APHA (M T The number is at most 20, preferably at most 15, and more preferably at most 10.

[0243] 33. The method as described in any one of Examples 1 to 32, wherein the mixture M T A further characteristic is that the permanganate absorbance number Ω PAN (M T ) and UV absorbance Ω UV (M T One or more of ) where Ω PAN (M T The value is at most 20, preferably at most 15, more preferably at most 10, and wherein Ω UV (M TThe value is at most 0.75, preferably at most 0.25, and more preferably at most 0.1.

[0244] 34. The method of any one of Examples 1 to 33, wherein the material M according to (i) comprises waste, preferably composed of therefrom, wherein the waste more preferably comprises one or more of at least one textile waste and at least one engineering plastic waste, more preferably composed of therefrom, and more preferably comprises at least one textile waste, more preferably composed of therefrom;

[0245] Preferably, the material M is composed of polyamide 6 in an amount of 10 to 99 wt%, more preferably 30 to 98.5 wt%, more preferably 50 to 98 wt%, and even more preferably 80 to 98 wt%.

[0246] Preferably, in addition to polyamide 6, the material M also contains one or more other organic polymer compounds, which more preferably include, but are not limited to, one or more of the following: at least one polyurethane elastic fiber, at least one polyethylene terephthalate, at least one polytetrahydrofuran, at least one polyamide 6.6, at least one polyurethane, at least one polyester, at least one cellulose material, and at least one rubber material, which includes one or more of at least one natural rubber material and at least one synthetic rubber material.

[0247] 35. The method as described in any one of Examples 1 to 34, further comprising:

[0248] (v) The mixture M obtained according to (iv) F The mixture was stored in an inert gas atmosphere at a temperature of up to 80°C for a duration Δt. Σ Obtain the stored mixture M S The storage time Δt Σ It is at least 1 day.

[0249] 36. The method as described in any one of Examples 1 to 35, wherein, according to (v), the mixture M F It should be stored away from light.

[0250] 37. The method as described in any one of Examples 1 to 36, wherein, according to (v), the storage time Δt Σ It is at least 7 days, more preferably at least 14 days, and more preferably in the range of 14 to 28 days.

[0251] 38. The method as described in any one of Examples 1 to 37, wherein, according to (v), the inert gas atmosphere comprises one or more of nitrogen and argon, preferably argon.

[0252] 39. The method as described in any one of Examples 1 to 38, wherein, according to (v), the mixture M F In the mixture M F The storage temperature δ is in the range of 20°C to 80°C, preferably in the range of 25°C to 80°C, more preferably in the range of 35°C to 77°C, and even more preferably in the range of 50°C to 75°C. S The storage pressure p of the inert gas atmosphere is preferably in the range of 0.5 to 10 bar, more preferably in the range of 0.75 to 5 bar, and even more preferably in the range of 1 to 2 bar. S Download and save.

[0253] 40. The method as described in Example 39, wherein, during storage according to (v),

[0254] (δ S / °C) = -2.6 • (x H2O (M F ) / weight-%) + C S

[0255] Where C S = 77 ± 10, preferably C S = 77 ± 5.

[0256] 41. A storage mixture M F The method involves a mixture containing ε-caprolactam and water and having a purity of at least 99% Ω. GC (M F APHA value of up to 20 Ω APHA (M F ) and based on the mixture M F The total weight must be at least 0.1 wt% water content x H2O (M F The mixture M F It can be obtained or acquired by the method according to any one of Examples 1 to 34, the method comprising placing the mixture M F The mixture was stored in an inert gas atmosphere at a temperature of up to 80°C for a duration Δt. Σ Obtain the stored mixture M S The storage time Δt Σ It is at least 1 day.

[0257] 42. The method as described in Example 41, wherein the mixture M F It should be stored away from light.

[0258] 43. The method as described in Examples 41 or 42, wherein the storage time Δt Σ It is at least 7 days, more preferably at least 14 days, and more preferably in the range of 14 to 28 days.

[0259] 44. The method of any one of Examples 41 to 43, wherein the inert gas atmosphere comprises one or more of nitrogen and argon.

[0260] 45. The method as described in any one of Examples 41 to 44, wherein the mixture M F In the mixture M F The storage temperature δ is in the range of 20°C to 80°C, preferably in the range of 25°C to 80°C, more preferably in the range of 35°C to 77°C, and even more preferably in the range of 50°C to 75°C. S The storage pressure p of the inert gas atmosphere is preferably in the range of 0.5 to 10 bar, more preferably in the range of 0.75 to 5 bar, and even more preferably in the range of 1 to 2 bar. S Download and save.

[0261] 46. ​​The method as described in Example 45, wherein, during storage,

[0262] (δ S / °C) = -2.6 • (x H2O (M F ) / weight-%) + C S

[0263] Where C S = 77 ± 10, preferably C S = 77 ± 5.

[0264] 47. A liquid mixture M F It contains ε-caprolactam and water and has a purity of at least 99% Ω. GC (M F APHA value of up to 20 Ω APHA (M F ) and based on the mixture M F The total weight must be at least 0.1 wt% water content x H2O (M F The mixture M F Preferably, the mixture M can be obtained or acquired by the method according to any one of Examples 1 to 34. F It exhibits storage stability Σ after storage time Δt. Δt , where Σ Δt From APHA value Ω APHA (Δt) characterization.

[0265] 48. The mixture as described in Example 47, wherein Δt is 14 days, and the storage stability Σ after the storage time. 14 From APHA value Ω APHA (14) Characterization, in which

[0266] -If Ω APHA (M F If it is less than 5, then Ω APHA (14) ≤ 10;

[0267] -If Ω APHA (M F If Ω is in the range of 5 to 8, then APHA (14) ≤ 2 Ω APHA (M F );

[0268] -If Ω APHA (M F If ) > 8, then Ω APHA (14) ≤ 1.5 Ω APHA (M F )).

[0269] 49. The mixture as described in Example 47 or 48, wherein Δt is 28 days, and the storage stability Σ after the storage time. 28 From APHA value Ω APHA (28) Characterization, in which

[0270] -If Ω APHA (M F If it is less than 4, then Ω APHA (28) ≤ 10;

[0271] -If Ω APHA (M F If the value is in the range of 4 to 8, then Ω APHA (28) ≤ 3 Ω APHA (M F );

[0272] -If Ω APHA (M F If ) > 8, then Ω APHA (28) ≤ 2 Ω APHA (M F ).

[0273] 50. The mixture as described in any one of Examples 47 to 49, wherein the storage stability Σ after storage time Δt is... Δt Further absorption by permanganate ΩPAN (Δt) and UV absorbance Ω UV One or more of the characteristics in (Δt).

[0274] 51. The mixture as described in Example 50, wherein Δt is 14 days, and the storage stability Σ after the storage time. 14 Characterized by one or more of the following: permanganate absorbance number Ω PAN (14), of which

[0275] -If Ω PAN (M F If it is less than 5, then Ω PAN (14) ≤ 10;

[0276] -If Ω PAN (M F If Ω is in the range of 5 to 8, then PAN (14) ≤ 1.5 Ω PAN (M F );

[0277] -If Ω PAN (M F If ) > 8, then Ω PAN (14) ≤ 1.25 Ω PAN (M F );

[0278] and UV absorption Ω UV (14), of which

[0279] -If Ω UV (M F If it is less than 0.02, then Ω UV (14) ≤ 0.05;

[0280] -If Ω UV (M F If Ω is in the range of 0.02 to 0.03, then UV (14) ≤ 3 Ω UV (M F );

[0281] -If Ω UV (M F If ) > 0.03, then Ω UV (14) ≤ 1.25 Ω UV (M F ).

[0282] 52. The mixture as described in Example 50 or 51, wherein Δt is 28 days, and the storage stability Σ after the storage time.28 Characterized by one or more of the following: permanganate absorbance number Ω PAN (28), of which

[0283] -If Ω PAN (M F If it is less than 5, then Ω PAN (28) ≤ 10;

[0284] -If Ω PAN (M F If Ω is in the range of 5 to 8, then PAN (28) ≤ 3 Ω PAN (M F );

[0285] -If Ω PAN (M F If ) > 8, then Ω PAN (28) ≤ 2 Ω PAN (M F );

[0286] and UV absorption Ω UV (28), of which

[0287] -If Ω UV (M F If it is less than 0.025, then Ω UV (28) ≤ 0.05;

[0288] -If Ω UV (M F If Ω is in the range of 0.025 to 0.05, then UV (28) ≤ 3 Ω UV (M F );

[0289] -If Ω UV (M F If ) > 0.05, then Ω UV (28) ≤ 2 Ω UV (M F ).

[0290] 53. A liquid mixture M S It comprises ε-caprolactam and water, and can be obtained or acquired by the method according to any one of Examples 35 to 40.

[0291] 54. The mixture as described in Example 53 has an APHA value Ω after a storage time Δt of 14 days. APHA (14), of which

[0292] -If ΩAPHA (M F If it is less than 4, then Ω APHA (14) ≤ 10;

[0293] -If Ω APHA (M F If the value is in the range of 4 to 8, then Ω APHA (14) ≤ 2 Ω APHA (M F );

[0294] -If Ω APHA (M F If ) > 8, then Ω APHA (14) ≤ 1.5 Ω APHA (M F ).

[0295] 55. The mixture as described in Examples 53 or 54 has an APHA value Ω after a storage time Δt of 28 days. APHA (28), of which

[0296] -If Ω APHA (M F If it is less than 4, then Ω APHA (28) ≤ 10;

[0297] -If Ω APHA (M F If the value is in the range of 4 to 8, then Ω APHA (28) ≤ 3 Ω APHA (M F );

[0298] -If Ω APHA (M F If ) > 8, then Ω APHA (28) ≤ 2 Ω APHA (M F ).

[0299] 56. The mixture as described in any one of Examples 53 to 55, having a permanganate absorbance number Ω after a storage time Δt. PAN (14) and UV / Vis absorbance Ω UV (14) One or more of the following, among which

[0300] -If Ω PAN (M F If it is less than 5, then Ω PAN (14) ≤ 10;

[0301] -If Ω PAN (M FIf Ω is in the range of 5 to 8, then PAN (14) ≤ 1.5 Ω PAN (M F );

[0302] -If Ω PAN (M F If ) > 8, then Ω PAN (14) ≤ 1.25 Ω PAN (M F );

[0303] And among them

[0304] -If Ω UV (M F If it is less than 0.01, then Ω UV (14) ≤ 0.05;

[0305] -If Ω UV (M F If Ω is in the range of 0.01 to 0.03, then UV (14) ≤ 3 Ω UV (M F );

[0306] -If Ω UV (M F If ) > 0.03, then Ω UV (14) ≤ 1.25 Ω UV (M F ).

[0307] 57. The mixture as described in any one of Examples 53 to 56, having a permanganate absorbance number Ω after a storage time Δt. PAN (28) and UV / Vis absorbance Ω UV (28) One or more of the following, among which

[0308] -If Ω PAN (M F If it is less than 5, then Ω PAN (28) ≤ 10;

[0309] -If Ω PAN (M F If Ω is in the range of 5 to 8, then PAN (28) ≤ 3 Ω PAN (M F );

[0310] -If Ω PAN (M F If ) > 8, then Ω PAN (28) ≤ 2 ΩPAN (M F );

[0311] And among them

[0312] -If Ω UV (M F If it is less than 0.025, then Ω UV (28) ≤ 0.05;

[0313] -If Ω UV (M F If Ω is in the range of 0.025 to 0.04, then UV (28) ≤ 1.5 Ω UV (M F );

[0314] -If Ω UV (M F If ) > 0.03, then Ω UV (28) ≤ 1.25 Ω UV (M F ).

[0315] 58. The mixture M as described in any one of Examples 47 to 52 F Or a mixture M as described in any one of Examples 53 to 57 S Used as a material for chemical processes, preferably for polymerization reactions, and more preferably for the preparation of polyamide 6 precipitates.

[0316] 59. A method for preparing polyamide 6, the method comprising:

[0317] (A) Preparation of mixture M according to any one of Examples 1 to 34 F and / or provide a mixture M as described in any one of Examples 47 to 52 F ;

[0318] (B) Optionally, the mixture M F The mixture M is obtained by storing it under the storage conditions defined in any of Examples 35 to 40. S ;

[0319] (C) To make the mixture M prepared and / or provided according to (A) F And / or the mixture M according to (B) S It was subjected to the polymerization conditions of polyamide 6.

[0320] 60. A polyamide 6, which can be obtained or acquired by the method described in Example 59, having an APHA value of up to 10, preferably up to 9, more preferably up to 8.

[0321] 61. The method as described in any one of Examples 1 to 34, or 35 to 40, further comprising placing the mixture M F At least a portion of or the mixture M S At least a portion is supplied to polyamide 6 production unit U PP Among them, in U PP The polyamide 6 produced in this process is preferably supplied as a raw material to the textile material production unit U. TP From this unit U TP middle

[0322] (A) Obtaining textile materials M for market launch TE In the textile material M TE Lifespan T MTE Subsequently, it is collected, at least partially, as textile waste in textile material collection unit U. TC middle;

[0323] (B) Obtain the remaining material M RE As textile waste;

[0324] At least a portion of the textile waste according to (A), or at least a portion of the textile waste according to (B), or at least a portion of the textile waste according to (A) and at least a portion of the textile waste according to (B) shall be suitably provided as material M according to (i).

[0325] 62. The method as described in any one of Examples 1 to 34, or 35 to 40, further comprising placing the mixture M F At least a portion of or the mixture M S At least a portion is supplied to polyamide 6 production unit U PP Among them, in U PP The polyamide 6 produced in this process is preferably supplied as a raw material to the engineering plastics production unit U. EP From this unit U EP middle

[0326] (A) Obtaining engineering plastic materials M for market launch EP In the engineering plastic material M EP Lifespan T MEP Subsequently, it is collected, at least partially, as engineering plastic waste in the engineering plastics material collection unit U. EC middle;

[0327] (B) Obtain the remaining material M RE As engineering plastic waste;

[0328] At least a portion of the engineering plastic waste according to (A), or at least a portion of the engineering plastic waste according to (B), or at least a portion of the engineering plastic waste according to (A) and at least a portion of the engineering plastic waste according to (B) shall be suitably provided as material M according to (i).

[0329] 63. The mixture M as described in any one of Examples 47 to 52 F Or a mixture M as described in any one of Examples 53 to 57 S Uses for preparing polyamide 6, wherein the uses preferably further include using the polyamide 6 as a raw material for preparing one or more textile materials and engineering plastic materials, more preferably for preparing textile materials.

[0330] 64. A method for preparing polyamide 6, the method comprising using a mixture M according to any one of Examples 47 to 52 F Or the mixture M according to any one of Examples 53 to 57 S As a starting material, the method preferably further includes using the polyamide 6 as one or more of textile materials and engineering plastic materials, more preferably as a raw material for preparing textile materials.

[0331] 65. The mixture M as described in any one of Examples 47 to 52 F Or a mixture M as described in any one of Examples 53 to 57 S Use for preparing one or more polymers and polymer products; or a method for preparing one or more polymers and polymer products, said method comprising using a mixture M according to any one of Examples 47 to 52. F Or the mixture M according to any one of Examples 53 to 57 S As starting material.

[0332] 66. The use or method as described in Example 65, wherein the polymer, or the polymer product, or the polymer and the polymer product are in the form of at least one of particles, strands, rods, plates, tubes, foils, layers, films, sheets, fibers, filaments, coatings, extruded articles, molded articles, soft foams, semi-rigid foams and rigid foams.

[0333] 67. The use or method as described in Examples 65 or 66, wherein the polymer, or the polymer product, or the polymer and the polymer product comprise polyamide 6 and optionally at least one other polymer compound, said polyamide 6 being at least partially composed of a mixture M according to any one of Examples 47 to 52. FOr the mixture M according to any one of Examples 53 to 57 S Available or obtainable, wherein the at least one additional polymer compound preferably includes one or more of the following: at least one polyamide 6.6, at least one polyethylene terephthalate, at least one polyurethane, at least one polyester, at least one cellulose material, and at least one rubber material, the rubber material including one or more of at least one natural rubber material and at least one synthetic rubber material.

[0334] 68. The use or method as described in any one of Examples 65 to 67, wherein the polymer, or the polymer product, or the polymer and the polymer product are one or a portion of one of the following:

[0335] - Automotive parts, preferably cylinder head covers, engine covers, housings for turbocharged air coolers, turbocharged air cooler baffles, intake pipes, intake manifolds, connectors, gears, fan impellers, coolant tanks, housings or housing parts for heat exchangers, coolant coolers, turbocharged air coolers, thermostats, water pumps, radiators, fasteners for electric vehicles or battery system parts, dashboards, steering column switches, seats, headrests, center consoles, transmission components, door modules, automotive exterior trim for A-pillar, B-pillar, C-pillar or D-pillar covers, spoilers, door handles, exterior mirrors, windshield wipers, windshield wiper protective housings, decorative grilles, cover strips, roof racks, window frames, sunroof frames, antenna panels, headlights, taillights, airbags, roof mats, oil pans, fuel cells, heat shields and / or seat cushions;

[0336] - Fabrics, clothing, preferably shirts, trousers, sweaters, boots, shoes, soles, tights, yarns, fabrics and / or jackets;

[0337] - Electrical components, preferably electrical parts, passive electronic parts, active electronic parts, printed circuit boards, housing parts, foils, circuits, switches - such as microswitches, plugs, sockets, distributors, relays, resistors, capacitors, inductors, spools, lamps, diodes - such as LEDs, transistors, connectors, regulators, integrated circuits (ICs), processors, controllers, memories, sensors, microbuttons, semiconductors, such as reflector housings for light-emitting diodes, fasteners, spacers, bolts, strips, slide rails, screws, nuts, membrane hinges, snap hooks (buckles) and / or spring tongues for electrical and / or electronic components;

[0338] - Consumer goods and / or pharmaceutical products, preferably tennis strings, climbing ropes, bristles, brushes, artificial turf, 3D printed filaments, lawnmowers, zippers, Velcro, paper machine netting, extrusion coatings, fishing lines, fishing nets, marine pipelines and ropes, vials, syringes, ampoules, bottles, sliding elements, spindle nuts, chain conveyors, sliding bearings, rollers, wheels, gears, ring gears, screws and spring dampers, hoses, pipes, cable sheaths, sockets, switches, cable ties, fan impellers, carpets, boxes and / or bottles for cosmetics, mattresses, cushions, and insulating materials;

[0339] - Packaging for the food industry, preferably single-layer and / or multi-layer blown film, cast film (single-layer and / or multi-layer), biaxial stretch film, or laminated film.

[0340] 69. The use or method as described in any one of Examples 65 to 68, wherein the polymer, or the polymer product, or the polymer and the polymer product contain polyamide 6, which is a mixture M according to any one of Examples 47 to 52. F Or the mixture M according to any one of Examples 53 to 57 S It may be obtained or acquired in an amount of 1 wt% or more, preferably 2 wt% or more, more preferably 5 wt% or more, more preferably 15 wt% or more, more preferably 30 wt% or more, more preferably 40 wt% or more, more preferably 60 wt% or more, more preferably 80 wt% or more, more preferably 90 wt% or more, more preferably 95 wt% or more; and / or in an amount of 100 wt% or less, preferably 95 wt% or less, more preferably 90 wt% or less, more preferably 50 wt% or less, more preferably 25 wt% or less, more preferably 10 wt% or less.

[0341] In embodiment 69, the appropriate quantities are preferably determined based on identity preservation and / or segregation and / or balance of quality and / or book and claim chain of custody models, more preferably based on balance of quality, and even more preferably based on the International Sustainability and Carbon Certification (ISCC) standard.

[0342] With respect to Examples 65 to 69, the preparation of polymers, polymer products, or polymers and polymer products may include one or more synthetic steps and may be carried out by conventional synthesis and techniques known to those skilled in the art. Examples of synthetic steps are described in “Industrial Organic Chemistry”, Volume 3, Wiley-VCH, 1997; ISBN: 978-3-527-28838-0; “Kunststoffhandbuch”, Volume 11 of 17 sub-volumes, Carl Hanser Verlag, especially Volume 6, “Polyamide”, 1st edition, 1966; “Injection Molding Reference Guide”, 4th edition, CreateSpace, 2011, ISBN: 978-1466407824; WO 2008 / 155271 A1 and WO 2013 / 139827 A1, each of which is incorporated herein by reference.

[0343] As used in the context of this invention, the term "bar" refers to absolute pressure, also known as "bar (absolute value)" or "absolute pressure".

[0344] In the context of this invention, the abbreviation "d" used as a physical unit in the terminology describes a time interval "day," that is, a time interval of (24 ± 1) h, preferably (24 ± 0.5) h. For example, a time interval of 14 days refers to (336 ± 1) h, preferably (336 ± 0.5) h, and a time interval of 28 days refers to (672 ± 1) h, preferably (672 ± 0.5) h.

[0345] As used herein, the term "textile material" encompasses textile and non-textile raw materials processed by various methods into linear, planar, and three-dimensional structures. It includes linear textile structures produced from them, such as yarns, twisted yarns, and ropes; sheet-like textile structures, such as woven fabrics, knitted fabrics, braids, stitch-knitted fabrics, nonwovens, and felts; and three-dimensional textile structures, i.e., body structures, such as textile hoses, stockings, or textile semi-finished products; and further includes those finished products made from the aforementioned products through assembly, unassembly, and / or other operations to reach a marketable state for forward transfer to processors, traders, or end consumers. As used herein, the term "textile waste" encompasses textile materials as defined above, whose inherent value has been consumed from the perspective of their current holder, and therefore, is waste material for said holder.

[0346] As used herein, the term "engineering plastics" refers to high-performance plastic grades that possess physical properties that enable them to be used long-term in structural applications, over a wide temperature range, under mechanical stress, and in challenging chemical and physical environments, such as those used to manufacture plastic parts that replace traditional engineering materials like metals and ceramics. Engineering plastics are particularly suitable for the manufacture of mechanical parts in several industries, such as automotive, medical, electrical and electronics, aerospace, construction, and consumer goods. As used herein, the term "engineering plastic waste" encompasses engineering plastic materials as defined above that have had their inherent value consumed from the perspective of their current owner, and are therefore considered end-of-life materials for that owner.

[0347] The invention is further illustrated by the following reference examples, examples, and comparative examples.

[0348] Reference Example 1

[0349] 1.1 Determination of APHA color of ε-caprolactam

[0350] The APHA color is determined according to ISO 8112. In principle, the extinction E of a 50% (by weight) aqueous solution of ε-caprolactam is determined in a cuvette of length l = 5 cm at a wavelength λ = 390 nm and expressed in Hassen units (platinum-cobalt scale). For this purpose, the measured extinction E is multiplied by a factor f = 150. The Hassen unit (platinum-cobalt scale) is defined as the color of a solution containing 1 mg of platinum in the form of hexachloroplatinic acid in 1 l of water in the presence of 2 mg cobalt(II) chloride hexahydrate. The Hassen unit corresponds to the APHA unit. A standard solution of 500 Hassen units is prepared as follows: 1.000 g of cobalt(II) chloride hexahydrate (CoCl2 • 6 H2O) and 1.245 g of potassium(IV) hexachloroplatinate (K2PtCl6) are dissolved in 100 ml of hydrochloric acid with an a concentration of 1.19 g / ml. Transfer the solution to a 1000 ml volumetric flask and fill it to the calibration mark. This solution contains 500 mg platinum and corresponds to 500 Hasen units. Dissolve a specific amount of ε-caprolactam (typically in the range of 5 to 50 g) in 50 ml of distilled water in a 250 ml Erlenmeyer flask. Mix the solution and let it stand until the bubbles disappear. Fill two cuvettes of a spectrophotometer (suitable for measurements at wavelength λ = 390 nm) with distilled water, place them in the beam path, and adjust the spectrophotometer to E = 0 at λ = 390 nm. Then, remove the distilled water from the sample cuvette and subsequently fill it with the ε-caprolactam solution. Then, relative to the control cuvette containing distilled water, measure at λ = 390 nm (E = 0). 390The extinction E of this solution is determined by [the following]. The color number X (Hassen units, platinum-cobalt scale) is calculated as X = E • f = 150 • E 390 X is rounded to the next integer.

[0351] 1.2 Determination of the purity of ε-caprolactam

[0352] The purity of ε-caprolactam and the corresponding amounts of impurities were determined by GC-FID / MS using a GC (Agilent 7890A) coupled with two MSDs (Agilent 5975C) for electron shock ionization and chemical ionization. The corresponding area % value obtained from the measurement represents the GC purity value Ω according to the invention. GC .

[0353] 1.3 Determination of PAN in ε-caprolactam

[0354] The PAN value is determined according to DIN ISO 8660.

[0355] 1.4 Determination of UV-Vis absorbance of ε-caprolactam

[0356] The UV / Vis absorbance value is determined according to DIN ISO 7059 at a wavelength of 290 nm.

[0357] Reference Example 2

[0358] To determine the storage stability Σ after storage time Δt Δt In the corresponding and comparative examples, 10-25 g of the given material was stored in a glass container in the dark at a constant temperature and under an inert (argon) gas atmosphere with constant stirring at 250-500 rpm using a Teflon-coated magnetic stir bar for a predetermined time Δt. The temperature was maintained constant in an oil bath using a contact thermometer. During the measurement, the material was kept at the corresponding temperature and the gas atmosphere was never lower than 15%.

[0359] Reference Example 3: Storage stability of petrochemically derived ε-caprolactam

[0360] ε-caprolactam (15.0 g) was prepared via a reaction sequence of (i) cyclohexane oxidation with air, (ii) oxime reaction with hydroxylamine sulfate, and (iii) Beckmann rearrangement (catalyzed by fuming sulfuric acid / sulfuric acid), and has the following specifications:

[0361] Ω UV = 0.03; Ω APHA = 2; Ω PAN = 3; Ω GC = 99.9%;

[0362] Store at 85°C in an inert atmosphere and protected from light for 28 days.

[0363] The following specifications were observed after 28 days:

[0364] Ω UV (28) = 0.16; Ω APHA (28) = 4; Ω PAN (28) = 8.

[0365] This reference example 3 shows that (routinely) synthesized ε-caprolactam can be stored at 85°C for 28 days, and the specifications, especially Ω-caprolactam, remain unchanged after 28 days. APHA (28) and Ω PAN (28) There were no significant changes, leading to the conclusion that the material exhibits good storage stability. 28 .

[0366] Comparative Example 1: Inadequate storage stability of recovered ε-caprolactam

[0367] The depolymerized and purified ε-caprolactam (15.0 g) has the following specifications:

[0368] Ω UV (M T ) = 0.03; Ω APHA (M T ) = 2; Ω PAN (M T ) = 7; Ω GC (M T = 99.9%;

[0369] Store at 85°C in an inert atmosphere and protected from light for 14 and 28 days, respectively.

[0370] The following specifications were observed after 14 days:

[0371] Ω UV (14) = 0.28; Ω APHA (14) = 5; Ω PAN (14) = 13.

[0372] The following specifications were observed after 28 days:

[0373] Ω UV (28) = 0.87; Ω APHA (28) = 23; Ω PAN (28) = 23.

[0374] Compared to Reference Example 3, the ε-caprolactam according to Comparative Example 1 was not obtained by conventional synthesis, but rather via hydrolysis-depolymerization and subsequent purification as described in the context of this invention, thereby producing an ε-caprolactam mixture M. T The recovered ε-caprolactam (which exhibits the same characteristics as the ε-caprolactam according to Reference Example 3 Ω) UV Ω APHA Ω PAN and Ω GC This mixture M T It was found that the storage conditions in Reference Example 2 resulted in insufficient stability, such as from Ω APHA Value (where Ω) APHA (28) = 12.5 Ω APHA (M T )) or Ω UV Value (where Ω) UV (28) = 29 Ω UV (M T The huge relative increase can be seen from this.

[0375] Comparative Example 2: Inadequate Storage Stability of Recovered ε-caprolactam

[0376] According to Comparative Example 2, the ε-caprolactam was not obtained through conventional synthesis, but rather via hydrolysis and depolymerization as described in the context of this invention, followed by purification and recovery, thereby producing an ε-caprolactam mixture M. T The depolymerized and purified ε-caprolactam (15.0 g) has the following specifications:

[0377] Ω UV (M T ) = 0.73; Ω APHA (M T ) = 10; Ω PAN (M T ) = 21; Ω GC (M T = 99.9%;

[0378] Store at 85°C in an inert atmosphere and protected from light for 28 days.

[0379] The following specifications were observed after 28 days:

[0380] Ω UV (28) = 1.68; Ω APHA (28) = 54; Ω PAN (28) = 33.

[0381] As for the material in Comparative Example 1, insufficient storage stability was observed, for example, considering Ω APHA Value (where Ω) APHA (28) = 5.4 Ω APHA (M F The relative increase of ).

[0382] Example 1: Storage stability of recovered ε-caprolactam

[0383] Using the same materials as in Comparative Example 2 (wherein based on recovered ε-caprolactam obtained, for example, through hydrolysis, depolymerization, and subsequent purification), an aqueous mixture M was prepared. F It is then stored under the storage conditions according to the invention. Specifically, the depolymerized and purified ε-caprolactam (15.0 g) used has the following specifications:

[0384] Ω UV (M F ) = 0.73; Ω APHA (M F ) = 10; Ω PAN (M F ) = 21; Ω GC (M F = 99.9%.

[0385] This material was stored at 70°C as a mixture containing 2.0 wt% demineralized water under an inert argon atmosphere and protected from light for 28 days.

[0386] The following specifications were observed after 28 days:

[0387] Ω UV (28) = 0.73; Ω APHA (28) = 19; Ω PAN (28) = 20.

[0388] Compared to the corresponding specifications in Comparative Example 2, all values ​​Ω UV (28) (Ω) APHA (28) and Ω PAN (28) shows a significantly lower increase (if any). In particular, Ω was found to be significantly lower. APHA (28) = 1.9 Ω APHA (M F ); Ω UV (28) = 1.0 Ω UV (M F ); Ω PAN (28) = 0.95 Ω PAN (M F ).

[0389] Example 2: Storage stability of recovered ε-caprolactam

[0390] The used ε-caprolactam is recovered via hydrolysis and depolymerization as described in the context of this invention, followed by purification, thereby producing an ε-caprolactam mixture M. F The depolymerized and purified ε-caprolactam (15.0 g) has the following specifications:

[0391] Ω APHA (M F ) = 5; Ω GC (M F = 99.9%;

[0392] It was stored at 70°C as a mixture containing 2.0% by weight of demineralized water under an inert atmosphere and protected from light for 28 days.

[0393] The following specifications were observed after 28 days:

[0394] Ω APHA (28) = 11.

[0395] Discovery such as from Ω APHA (28) = 2.2 Ω APHA (M F As can be seen, the aqueous mixture of the present invention provides the recovered ε-caprolactam with favorable storage stability.

[0396] Example 3: Storage stability of recovered ε-caprolactam

[0397] The used ε-caprolactam is recovered via hydrolysis and depolymerization as described in the context of this invention, followed by purification, thereby producing an ε-caprolactam mixture M. F The depolymerized and purified ε-caprolactam (15.0 g) has the following specifications:

[0398] Ω UV (M F ) = 0.03; Ω APHA (M F ) = 1; Ω PAN (M F = 4; Ω GC (M F = 99.9%;

[0399] It was then stored at 70°C with 2.0% by weight of demineralized water in an inert atmosphere and protected from light for 14 and 28 days.

[0400] The following specifications were observed after 14 days:

[0401] Ω UV (14) = 0.03; Ω APHA (14) = 1; Ω PAN (14) = 4.

[0402] The following specifications were observed after 28 days:

[0403] Ω UV (28) = 0.04; Ω APHA (28) = 3; Ω PAN (28) = 5.

[0404] As can be seen from all the values, the aqueous mixture of the present invention provides the recovered ε-caprolactam with very favorable storage stability.

[0405] Example 4: Storage stability of recovered ε-caprolactam

[0406] The ε-caprolactam used is the ε-caprolactam of Example 3, i.e., a material with the following specifications:

[0407] Ω UV (M F ) = 0.03; Ω APHA (M F ) = 1; Ω PAN (M F = 4; Ω GC (M F = 99.9%.

[0408] Compared to Example 3, the material that underwent 28 days of storage was a different aqueous mixture, namely a mixture containing 5.0 wt% demineralized water. Storage was carried out at 60°C under the same conditions as in Example 3 in all other respects.

[0409] The following specifications were observed after 28 days:

[0410] Ω UV (28) = 0.04; Ω APHA (28) = 1; Ω PAN (28) = 3.

[0411] As can be seen from all the values, the aqueous mixture of the present invention provides the recovered ε-caprolactam with very favorable storage stability.

Claims

1. A method for preparing liquid ε-caprolactam mixtures M F The method includes (i) Provide stream S M The stream contains a solid material M containing polyamide 6; (ii) Preparation based on S M Aqueous depolymerization mixtures; (iii) The depolymerized mixture prepared according to (ii) is reacted in reaction unit U R The polyamide 6 was subjected to depolymerization conditions to obtain a product containing a concentration of c SR Liquid aqueous flow S of ε-caprolactam dissolved in water R The S stream R It further contains one or more impurities; and optionally the liquid aqueous stream S R Transferred to evaporation unit U E In the middle, by S R Obtain the concentration c SL Liquid aqueous flow S of ε-caprolactam dissolved in water L , where c SL > c SR And further by S R Obtain one or more water vapor streams S V ; (iv) The stream S R Optionally, this stream S L Transferred to ε-caprolactam purification unit U P In the middle, and (iv.1) From this unit U P To obtain the mixture M F ;or (iv.2) From this unit U P Obtain mixture M T The mixture has at least 99% ε-caprolactam purity Ω GC (M T APHA value of up to 20 Ω APHA (M T ) and based on the mixture M T Total weight at most 0.05% water content x H2O (M T ), and to the mixture M T Add water to obtain mixture M. F ; Wherein the mixture M F It has at least 99% purity of ε-caprolactam Ω GC (M F APHA value of up to 20 Ω APHA (M F ) and based on the mixture M F The total weight must be at least 0.1 wt% water content x H2O (M F ).

2. The method as described in claim 1, wherein, Ω GC (M F It is at least 99.5%, more preferably at least 99.8%, more preferably at least 99.9%, and Ω APHA (M F The value is at most 15, preferably at most 10, and more preferably at most 5.

3. The method as described in claim 1 or 2, wherein, The mixture M F It has a temperature in the range of 20°C to 80°C, preferably in the range of 35°C to 77°C, and more preferably in the range of 50°C to 75°C.

4. The method according to any one of claims 1 to 3, wherein, x H2O (M F The content is in the range of 0.1 to 10 wt%, preferably in the range of 0.2 to 8 wt%, and more preferably in the range of 0.5 to 6 wt%.

5. The method according to any one of claims 1 to 4, wherein, According to (v), the purification unit U P Including water separation unit U WS and distillation unit U D The method preferably includes placing the stream S R Optionally, this stream S L Feed to U WS From U WS Obtain the concentration c UWS The flow of ε-caprolactam S UWS , will the stream S UWS Feed into the distillation unit U D From U D Obtain the concentration c MF The mixture M of ε-caprolactam F , where c SR < c UWS <<< c MF Preferably, where c SL < c UWS <<< c MF ; The water separation unit U WS Preferably, it includes at least two water ion units U WS1 and U WS2 More preferably, two water ion units U connected in series WS1 and U WS2 , where the stream S R Optionally, this stream S L Feed into U WS1 In, among them in U WS1 Downstream and in U WS2 Upstream, a separation unit U is preferably provided. I The method preferably includes from U WS1 Obtaining water flow S UWS1 , will the stream S UWS1 Feed into the separation unit U I In the middle, from U I Obtaining water flow S UI and the stream S UI Feeding into unit U WS2 In, among them in U I In the middle, from S UWS1 One or more impurities can be separated from U, thereby separating them from U. I Obtain impurity flow S I The impurity preferably comprises at least one contained in S according to (iii). R Impurities in the separation unit U, wherein at least one of the impurities is an organic compound having a higher boiling point than ε-caprolactam. I It is a high-boiling-point separation unit; The purification unit U P Preferably in this unit U D The downstream of the crystallization unit U CR and chemical processing unit U OD One or more of them, the method includes from U CR China or from U OD To obtain the mixture M F .

6. The method of claim 5, wherein, This unit U OD Chemical treatments include (a) Provide from this distillation unit U D The preferred liquid flow S containing ε-caprolactam UD Or from this crystallization unit U CR The preferred liquid flow S containing ε-caprolactam CR The flow S UD or the flow S CR Further comprising one or more oxidizable organic impurity compounds X, wherein the stream S UD Or the stream S CR It has at least 99% purity of ε-caprolactam Ω GC (S C And it shows the weight ratio r of one or more organic compounds X relative to ε-caprolactam. XC ; (b) Providing a flow containing at least one permanganate S O ; (c) From this flow S UD and the S stream O Or by the flow S SCR and the S stream O Preparation of Oxidation Reaction Separate Mixture M OE And make the mixture M OE Under oxidative reaction conditions, an oxidation product stream S containing ε-caprolactam was obtained. P The oxidation product stream further comprises one or more oxidation products Y obtained by oxidation of at least a portion of the one or more compounds X, and optionally further comprises a portion of the one or more organic compounds X, wherein the stream S P The weight ratio r of organic compound X relative to ε-caprolactam is shown. XCP , where 0 ≤ r XCP < r XC Furthermore, it demonstrates the weight ratio r of one or more products Y relative to ε-caprolactam. YCP , where r YCP > 0; (d) From the stream S P The mixture M is obtained by separating at least a portion of one or more oxidation products Y and optionally at least a portion of organic compound X. F Or the mixture M T It exhibits a weight ratio r of oxidation product Y to ε-caprolactam. YCT , where 0 ≤ r YCT < r YCP Furthermore, it demonstrates the weight ratio r of organic compound X relative to ε-caprolactam. XCT , where 0 ≤ r XCT < r XC .

7. The method of claim 6, wherein, Included in the stream S provided according to (b) O The at least one permanganate in the composition includes at least an alkali metal permanganate, preferably composed of the same, wherein More preferably, the at least one alkali metal permanganate comprises one or more of sodium permanganate and potassium permanganate, wherein preferably 0.5 to 100 wt% of the flow S provided according to (b) O Composed of permanganate, and wherein the flow S according to (b) is provided O Preferably, it further contains water; The oxidation reaction precipitate mixture M prepared according to (c) OE It exhibits a permanganate concentration calculated as MnO4 that is preferably in the range of 0.005 to 5 wt%, more preferably in the range of 0.01 to 3 wt%, and even more preferably in the range of 0.05 to 1 wt%. The oxidation reaction conditions according to (c) include the mixture M OE Preferably, the temperature T is in the range of 40°C to 140°C, more preferably in the range of 60°C to 100°C, and even more preferably in the range of 70°C to 90°C. OE ; The mixture M prepared according to (c) OE Preferably, it further contains water; Where the mixture M OE Subjected to oxidation reaction conditions in the chemical processing unit U OD The oxidation reaction unit U in OR The process is carried out in which the unit U OR Preferably, it includes one or more of at least one continuous stirred tank reactor and at least one tubular reactor.

8. The method of claim 6 or 7, further comprising providing a stream S containing at least one hydroxide. B The mixture M of the oxidative reaction product according to (c) OE From this flow S UD Or the stream S CR and by the flow S O and the S stream B Preparation, which includes the flow S B The at least one hydroxide in the mixture preferably comprises at least an alkali metal hydroxide, more preferably composed of the same, and more preferably, the at least one alkali metal hydroxide comprises sodium hydroxide, more preferably composed of the same. Preferably, 0.5 to 100 wt% of the stream S B Composed of hydroxides, wherein the flow S B Preferably, it further comprises water, wherein the oxidation reaction precipitate mixture M prepared according to (c) OE It exhibits a hydroxide concentration, calculated as OH, preferably in the range of 0.005 to 0.75 wt%, more preferably in the range of 0.01 to 0.5 wt%, and even more preferably in the range of 0.1 to 0.25 wt%.

9. The method according to any one of claims 6 to 8, wherein, The one or more oxidizable organic compounds X have a boiling point δ X / °C, where 0.5 ≤ (δ X / δ C ) ≤ 1.5, δ C / °C is the boiling point of ε-caprolactam, and at least one of the one or more oxidation products Y has a boiling point δ. Y / °C, where δ Y / °C ≠ δ C / °C, where the boiling point δ Y With boiling point δ C The difference Δδ between them is preferably at least 1°C, wherein according to (d) from the flow S P The separation of at least a portion of the one or more oxidation products Y and optionally at least a portion of the organic compound X preferably comprises making the stream S obtained according to (c) P Including the chemical processing unit U OD Distillation unit U in DT The middle undergoes distillation, from the distillation unit U DT To obtain as the mixture M F Or the mixture M T Stream S containing ε-caprolactam DT The unit U DT Preferably, it includes one or more distillation columns, more preferably one or two distillation columns, wherein at least one column is optionally configured as a side-flow column or a split-wall column.

10. The method according to any one of claims 5 to 9, wherein, The purification unit U P Further including crystallization unit U CR The method includes distilling from the distillation unit U D Obtain the concentration c UD The flow of ε-caprolactam S UD and the stream S UD Feed into the crystallization unit U CR From U CR Obtain the concentration c MF The mixture M of ε-caprolactam F ; Or, among them, the purification unit U P Further includes a chemical processing unit U OD The method includes distilling from the distillation unit U D Obtain the concentration c UD The flow of ε-caprolactam S UD and the stream S UD Feed into the chemical processing unit U OD From U OD Obtain the concentration c MF The mixture M of ε-caprolactam F ; Or, among them, the purification unit U P Further includes a chemical processing unit U OD and crystallization unit U CR The crystallization unit U CR Located in the distillation unit U D Downstream of, and the chemical processing unit U OD Located in the crystallization unit U CR Downstream of the distillation unit U, the method includes... D Obtain the concentration c UD The flow of ε-caprolactam S UD , will the stream S UD Feed into the crystallization unit U CR From this crystal U CR Obtain the concentration c CR The flow of ε-caprolactam S CR and the stream S CR Feed into the chemical processing unit U OD From U OD Obtain the concentration c MF The mixture M of ε-caprolactam F ; Or, among them, the purification unit U P Further includes a chemical processing unit U OD and crystallization unit U CR The chemical processing unit U OD Located in the distillation unit U D Downstream, and the crystallization unit U CR Located in this unit U CR Downstream of the distillation unit U, the method includes... D Obtain the concentration c UD The flow of ε-caprolactam S UD , will the stream S UD Feed into the chemical processing unit U OD From the chemical processing unit U OD Obtain the concentration c OD The flow of ε-caprolactam S OD and the stream S OD Feed into the crystallization unit U CR From U CR Obtain the concentration c MF The mixture M of ε-caprolactam F .

11. The method according to any one of claims 1 to 10, wherein, x H2O (M T The content is in the range of 0 to 0.05 wt%, preferably in the range of 0 to 0.01 wt%, and more preferably in the range of 0 to 0.001 wt%, wherein Ω GC (M T The content is at least 99.5%, preferably at least 99.8%, more preferably at least 99.9%, and wherein Ω APHA (M T The number is at most 20, preferably at most 15, and more preferably at most 10.

12. The method according to any one of claims 1 to 11, wherein, According to (i), the material M includes waste, preferably composed of it, wherein The waste more preferably includes one or more of at least one textile waste and at least one engineering plastic waste, more preferably composed of the latter, and more preferably includes at least one textile waste, more preferably composed of the latter. Preferably, the material M is composed of polyamide 6 in an amount of 10 to 99 wt%, more preferably 30 to 98.5 wt%, more preferably 50 to 98 wt%, and even more preferably 80 to 98 wt%. Preferably, in addition to polyamide 6, the material M also contains one or more other organic polymer compounds, which more preferably include, but are not limited to, one or more of the following: at least one polyurethane elastic fiber, at least one polyethylene terephthalate, at least one polytetrahydrofuran, at least one polyamide 6.6, at least one polyurethane, at least one polyester, at least one cellulose material, and at least one rubber material, which includes one or more of at least one natural rubber material and at least one synthetic rubber material.

13. The method of any one of claims 1 to 12, further comprising: (v) The mixture M obtained according to (iv) F The mixture was stored in an inert gas atmosphere at a temperature of up to 80°C for a duration Δt. Σ Obtain the stored mixture M S The storage time Δt Σ It is at least 1 day; According to (v), the mixture M F Preferably, it is stored away from light for a period of time Δt. Σ Preferably, the inert gas atmosphere comprises at least 7 days, more preferably at least 14 days, and even more preferably in the range of 14 to 28 days, and the mixture M F In the mixture M F The preferred storage temperature δ is in the range of 20°C to 80°C, more preferably in the range of 25°C to 80°C, more preferably in the range of 35°C to 77°C, and even more preferably in the range of 50°C to 75°C. S Download and save.

14. The method of claim 13, wherein, During storage according to (v), (δ S / °C) = - 2.6 • (x H2O (M F ) / wt% + C S Where C S = 77 ± 10, preferably C S = 77 ± 5.

15. A storage mixture M F The method involves a mixture containing ε-caprolactam and water and having a purity of at least 99% Ω. GC (M F APHA value of up to 20 Ω APHA (M F ) and based on the mixture M F The total weight must be at least 0.1 wt% water content x H2O (M F The mixture M F Preferably, the mixture M can be obtained or acquired by the method according to any one of claims 1 to 12, said method comprising placing the mixture M F The mixture was stored in an inert gas atmosphere at a temperature of up to 80°C for a duration Δt. Σ Obtain the stored mixture M S The storage time Δt Σ It is at least 1 day.

16. A liquid mixture M F It contains ε-caprolactam and water and has a purity of at least 99% Ω. GC (M F APHA value of up to 20 Ω APHA (M F ) and based on the mixture M F The total weight must be at least 0.1 wt% water content x H2O (M F The mixture M F Preferably, the mixture M can be obtained or acquired by the method according to any one of claims 1 to 12. F It exhibits storage stability Σ after storage time Δt. Δt , where Σ Δt From APHA value Ω APHA (Δt) characterization; Wherein the storage stability Σ is Δt = 14 d and after the storage time. 14 From APHA value Ω APHA (14) Characterization, preferably is -If Ω APHA (M F If it is less than 5, then Ω APHA (14) ≤ 10; -If Ω APHA (M F Preferably, Ω is in the range of 5 to 8. APHA (14) ≤ 2 Ω APHA (M F ); -If Ω APHA (M F If ) > 8, then Ω APHA (14) ≤ 1.5 Ω APHA (M F )); And where the storage stability Σ is for Δt = 28 days and after the storage time. 28 From APHA value Ω APHA (28) Characterization, preferably -If Ω APHA (M F If it is less than 4, then Ω APHA (28) ≤ 10; -If Ω APHA (M F If the value is in the range of 4 to 8, then Ω APHA (28) ≤ 3 Ω APHA (M F ); -If Ω APHA (M F If ) > 8, then Ω APHA (28) ≤ 2 Ω APHA (M F ).

17. A liquid mixture M comprising ε-caprolactam and water S The mixture M can be obtained or acquired by the method according to claim 13 or 14. S It has an APHA value Ω after a storage time of 14 days Δt. APHA (14), of which -If Ω APHA (M F If it is less than 4, then Ω APHA (14) ≤ 10; -If Ω APHA (M F If the value is in the range of 4 to 8, then Ω APHA (14) ≤ 2 Ω APHA (M F ); -If Ω APHA (M F If ) > 8, then Ω APHA (14) ≤ 1.5 Ω APHA (M F ); Furthermore, it exhibits an APHA value Ω after a storage time of 28 days Δt. APHA (28), of which -If Ω APHA (M F If it is less than 4, then Ω APHA (28) ≤ 10; -If Ω APHA (M F If the value is in the range of 4 to 8, then Ω APHA (28) ≤ 3 Ω APHA (M F ); -If Ω APHA (M F If ) > 8, then Ω APHA (28) ≤ 2 Ω APHA (M F ).

18. The mixture M as described in claim 16 F Or the mixture M as described in claim 17 S Used as a material for chemical processes, preferably for polymerization reactions, more preferably for the preparation of polyamide 6; and / or a method for preparing polyamide 6, the method comprising: (A) Preparation of mixture M according to any one of claims 1 to 12 F And / or provide the mixture M according to claim 16 F ; (B) Optionally, the mixture M F The mixture M is obtained by storing it under the storage conditions defined in claim 13 or 14. S ; (C) To make the mixture M prepared and / or provided according to (A) F And / or the mixture M according to (B) S Exposed to the polymerization conditions of polyamide 6; The polyamide 6, which can be obtained or acquired through the said use or method, has an APHA value of up to 10, preferably up to 9, more preferably up to 8.

19. The method according to any one of claims 1 to 12, or 13 or 14, It further includes the mixture M F At least a portion of or the mixture M S At least a portion is supplied to polyamide 6 production unit U PP Among them, in U PP The polyamide 6 produced in this process is preferably supplied as a raw material to the textile material production unit U. TP From this unit U TP middle (A) Obtaining textile materials M for market launch TE In the textile material M TE Lifespan T MTE Subsequently, it is collected, at least partially, as textile waste in textile material collection unit U. TC middle; (B) Obtain the remaining material M RE As textile waste; At least a portion of the textile waste according to (A), or at least a portion of the textile waste according to (B), or at least a portion of the textile waste according to (A) and at least a portion of the textile waste according to (B) shall be suitably provided as material M according to (i); And / or further include the mixture M F At least a portion of or the mixture M S At least a portion is supplied to polyamide 6 production unit U PP Among them, in U PP The polyamide 6 produced in this process is preferably supplied as a raw material to the engineering plastics production unit U. EP From this unit U EP middle (A) Obtaining engineering plastic materials M for market launch EP In the engineering plastic material M EP Lifespan T MEP Subsequently, it is collected, at least partially, as engineering plastic waste in the engineering plastics material collection unit U. EC middle; (B) Obtain the remaining material M RE As engineering plastic waste; At least a portion of the engineering plastic waste according to (A), or at least a portion of the engineering plastic waste according to (B), or at least a portion of the engineering plastic waste according to (A) and at least a portion of the engineering plastic waste according to (B) shall be suitably provided as material M according to (i).

20. The mixture M as described in claim 16 F Or the mixture M as described in claim 17 S Used for preparing one or more polymers and polymer products; or a method for preparing one or more polymers and polymer products, said method comprising using the mixture M as described in claim 16. F Or the mixture M as described in claim 17 S As starting material; The polymer, or the polymer product, or the polymer and the polymer product are preferably in the form of at least one of the following: granules, strands, rods, plates, tubes, foils, layers, films, sheets, fibers, filaments, coatings, extruded articles, molded articles, soft foams, semi-rigid foams and rigid foams; The polymer, or the polymer product, or the polymer and the polymer product preferably comprise polyamide 6 and optionally at least one other polymer compound, said polyamide 6 being at least partially composed of the mixture M as described in claim 16. F Or the mixture M as described in claim 17 S Available or obtainable, wherein the at least one additional polymer compound preferably comprises one or more of the following: at least one polyamide 6.6, at least one polyethylene terephthalate, at least one polyurethane, at least one polyester, at least one cellulose material, and at least one rubber material, the rubber material comprising one or more of at least one natural rubber material and at least one synthetic rubber material; The polymer, or the polymer product, or the polymer and the polymer product are preferably one of or a subset of the following: - Automotive parts, preferably cylinder head covers, engine covers, housings for turbocharged air coolers, turbocharged air cooler baffles, intake pipes, intake manifolds, connectors, gears, fan impellers, coolant tanks, housings or housing parts for heat exchangers, coolant coolers, turbocharged air coolers, thermostats, water pumps, radiators, fasteners for electric vehicles or battery system parts, dashboards, steering column switches, seats, headrests, center consoles, transmission components, door modules, automotive exterior trim for A-pillar, B-pillar, C-pillar or D-pillar covers, spoilers, door handles, exterior mirrors, windshield wipers, windshield wiper protective housings, decorative grilles, cover strips, roof racks, window frames, sunroof frames, antenna panels, headlights, taillights, airbags, roof mats, oil pans, fuel cells, heat shields and / or seat cushions; - Fabrics, clothing, preferably shirts, trousers, sweaters, boots, shoes, soles, tights, yarns, fabrics and / or jackets; - Electrical components, preferably electrical parts, passive electronic parts, active electronic parts, printed circuit boards, housing parts, foils, circuits, switches - such as microswitches, plugs, sockets, distributors, relays, resistors, capacitors, inductors, spools, lamps, diodes - such as LEDs, transistors, connectors, regulators, integrated circuits (ICs), processors, controllers, memories, sensors, microbuttons, semiconductors, such as reflector housings for light-emitting diodes, fasteners, spacers, bolts, strips, slide rails, screws, nuts, membrane hinges, snap hooks (buckles) and / or spring tongues for electrical and / or electronic components; - Consumer goods and / or pharmaceutical products, preferably tennis strings, climbing ropes, bristles, brushes, artificial turf, 3D printed filaments, lawnmowers, zippers, Velcro, paper machine netting, extrusion coatings, fishing lines, fishing nets, marine pipelines and ropes, vials, syringes, ampoules, bottles, sliding elements, spindle nuts, chain conveyors, sliding bearings, rollers, wheels, gears, ring gears, screws and spring dampers, hoses, pipes, cable sheaths, sockets, switches, cable ties, fan impellers, carpets, boxes and / or bottles for cosmetics, mattresses, cushions, and insulating materials; - Packaging for the food industry, preferably single-layer and / or multi-layer blown film, cast film (single-layer and / or multi-layer), biaxial stretch film, or laminated film; The polymer, or the polymer product, or the polymer and the polymer product preferably contain polyamide 6, which is derived from the mixture M as described in claim 16. F Or the mixture M as described in claim 17 S It may be obtained or acquired in an amount of 1 wt% or more, more preferably 2 wt% or more, more preferably 5 wt% or more, more preferably 15 wt% or more, more preferably 30 wt% or more, more preferably 40 wt% or more, more preferably 60 wt% or more, more preferably 80 wt% or more, more preferably 90 wt% or more, more preferably 95 wt% or more; and / or in an amount of 100 wt% or less, preferably 95 wt% or less, more preferably 90 wt% or less, more preferably 50 wt% or less, more preferably 25 wt% or less, more preferably 10 wt% or less.