Process for recovering toluene diamine from a toluene diisocyanate comprising material

Abstract

The invention relates in a first aspect to a process for recovering toluene diamine (TDA) from a toluene diisocyanate (TDI) comprising material, the process comprising: a) providing a TDI comprising material and optionally a material comprising a TDI based polyurethane; and b) contacting the material(s) provided in a) with an alcohol in an aqueous solution, thereby obtaining an aqueous mixture comprising TDA. A second aspect of the invention is directed to a combined process for preparing TDI and for recovering TDA, the process for preparing TDI comprising A) introducing a liquid stream comprising at least TDA and a solvent into a reaction zone; B) subjecting the TDA comprised in the liquid stream to isocyanate forming conditions in the reaction zone, comprising introducing a phosgene-containing stream into the reaction zone, thereby forming TDI; C) removing from the reaction zone a liquid mixture comprising TDI; D) optionally separating remaining phosgene, optionally carbon dioxide, and optionally hydrochloride from the liquid mixture and removing the solvent, thereby obtaining a TDI comprising phase; E) separating TDI from the TDI comprising phase, preferably by distillation, obtaining a material, which still comprises TDI but is depleted of TDI compared to the TDI comprising phase (TDI comprising material); the process for recovering TDA comprising F) contacting the TDI comprising material obtained in E) with an alcohol in an aqueous solution, thereby obtaining an aqueous mixture comprising TDA. A third aspect of the invention is related to TDA obtained or obtainable from a process of the first aspect or from the combined process of the second aspect. In a fourth aspect, the invention is directed to the use of the TDA of the third aspect for the preparation of TDI. A fifth aspect is directed to a method for preparing TDI comprising I) providing TDA of the third aspect; and II) preparing TDI from the TDA provided in I).

Description

Process for recovering toluene diamine from a toluene diisocyanate comprising materialThe invention relates in a first aspect to a process for recovering toluene diamine (TDA) from a toluene diisocyanate (TDI) comprising material, the process comprising: a) providing a TDI comprising material and optionally a material comprising a TDI based polyurethane; and b) contacting the material(s) provided in a) with an alcohol in an aqueous solution, thereby obtaining an aqueous mixture comprising TDA. A second aspect of the invention is directed to a combined process for preparing TDI and for recovering TDA, the process for preparing TDI comprising A) introducing a liquid stream comprising at least TDA and a solvent into a reaction zone; B) subjecting the TDA comprised in the liquid stream to isocyanate forming conditions in the reaction zone, comprising introducing a phosgene-containing stream into the reaction zone, thereby forming TDI; C) removing from the reaction zone a liquid mixture comprising TDI; D) optionally separating remaining phosgene, optionally carbon dioxide, and optionally hydrochloride from the liquid mixture and removing the solvent, thereby obtaining a TDI comprising phase; E) separating TDI from the TDI comprising phase, preferably by distillation, obtaining a material, which still comprises TDI but is depleted of TDI compared to the TDI comprising phase (TDI comprising material); the process for recovering TDA comprising F) contacting the TDI comprising material obtained in E) with an alcohol in an aqueous solution, thereby obtaining an aqueous mixture comprising TDA. A third aspect of the invention is related to TDA obtained or obtainable from a process of the first aspect or from the combined process of the second aspect. In a fourth aspect, the invention is directed to the use of the TDA of the third aspect for the preparation of TDI. A fifth aspect is directed to a method for preparing TDI comprising I) providing TDA of the third aspect; and II) preparing TDI from the TDA provided in I).State of the artToluene-2,4-diisocyanate (TDI) is one of the most important isocyanates and an important intermediate product in the plastics industry, for example, for preparing polyurethane plastics or foams. Processes for preparing toluene diisocyanate (TDI) from toluene via dinitrotoluene (DNT) and diaminotoluene (TDA) are widely known. Regarding the conversion of TDA to TDI, many process variants are known, such as phosgenation in the liquid phase (e.g. WO 99 / 54289 A1, WO 2004 / 056756 A1) or in the gas phase (e.g. DE 25870847 A, EP 1532107 A1, EP 0570799 A1 or EP 0289840 A1). In these processes, higher boiling by-products such as uretonimines, isocyanurates, carbodiimides are normally formed. The product TDI is separated to a certain extend from these by-products by distillation (e.g. EP 02023662 A1, EP3556745 A1) resulting in a TDI distillation residue. The TDI distillation process normally produces a liquid TDI distillation residue that still contains measurable quantities of TDI so that the residue is liquid. The liquid content can be reduced resulting in a dry or at least highly viscous TDI distillation residue. However, the distillation residue still comprises considerable amounts of TDI, usually between 20 and 80 % by weight, and in the range of from 1 to 80 % by weight of urea compounds, 0 to 40 % by weight of uretdiones, 0 to 60 % by weight of isocyanuric acid esters, 0.5 to 20 wt.% carbodiimides and 5 to 95 wt.% higher condensed or polymeric substances. Thus, for one the side-products cause a yield loss and second, the remaining amounts of TDI left in the TDI distillation residue also cause a severe yield loss. Accordingly, there is no lack of attempts to minimize this yield losses, wherein evaporating the residue to dryness and in this way remove any dissolved TDI as far as possible is already helpful (EP 13736539 A1, EP 80102037 A1, EP 94107545 A1).Regarding recovery of the TDI from the distillation residue, processes are known, including ammonolysis, e.g. WO 2006 / 134137 A1 , or reactions with alcohol amines (GB 2314082, ON 2021108991604, ON 2022102112203). A promising approach so far has been hydrolysis, wherein the TDI distillation residue is chemically broken up by use of water. For example, the residue is hydrolyzed at high temperature (>200°C) and high pressure (>25 bar) and TDA is released in this way, as described, for example, in DE 19827086 A. In the process according to CN 1003848, hydrolysis takes place in water at pressures of 40 to 250 bar and temperatures of 200 to 370°C. The hydrolysis reaction is normally catalyzed by adding bases (KOH, NaOH or amines). For example, WO 99 / 65868 A1 describes a process for working up toluene diisocyanate (TDI) distillation residues from the synthesis of TDI, the process comprising reacting the TDI distillation residues with water in a continuous or semicontinuous process in a backmixed reactor in the presence of reaction products of toluenediamine (TDA) residues and water. The temperature used is at least 200°C and a pressure of at least 25 bar is applied. The disadvantages of the known hydrolysis processes are the very harsh conditions, which sometimes require a considerable investment. In addition, basic catalysis often requires expensive special materials in view of corrosive effects.Thus, the objective technical problem underlying the present invention was the provision of an improved process for breaking up a TDI distillation residue, which does not have the disadvantages mentioned above.In a first aspect, the invention relates to a process for recovering toluene diamine (TDA) from a toluene diisocyanate (TDI) comprising material comprising a) providing a TDI comprising material and optionally a material comprising a TDI based polyurethane; b) contacting the material(s) provided in a) with an alcohol in an aqueous solution, thereby obtaining an aqueous mixture comprising TDA.A "TDI comprising material” comprises at least 0.01 weight-%, preferably at least 0.1 weight-%, of TDI, based on the total weight of the material being 100 weight-%. As indicated above, a TDI distillation residue is a residue obtained from distillation, which took place after TDI had been obtained from phosgenation of TDA. The initial TDI distillation residue still contains at least 5 weight-% TDI so that the residue is liquid, i.e. is a liquid TDI comprising material. This liquid TDI comprising material is either directly provided according to step (a) or the distillation residue is dried, i.e. the liquid content is reduced by evaporation, to remove most of the TDI, resulting in a solid residue from TDI distillation, which comprises less than 5 weight-% of TDI, preferably in the range of from 0.01 to less than 5 weight-% of TDI, based on the total weight of the solid residue being 100 weight-%. Both residues from TDI distillation, i.e. the liquid residue from TDI distillation and the solid residue from TDI distillation and drying additionally comprise one or more TDI based compound(s) such as TDI based carbodiimide, TDI based isocyanurate and TDI based uretonimine. Preferably, said liquid residue from TDI distillation and / or said solid residue from TDI distillation, more preferably at least said solid residue from TDI distillation, is then provided according to step (a) above as TDI comprising material. Herein, "TDI” is used as abbreviation for toluene diisocyanate, meaning a mixture comprising 2,4- and 2-6-toluene diisocyanate. "TDA” is used as abbreviation for toluene diamine, meaning a mixture comprising 2,4- and 2,6-toluene diamine.In some preferred embodiments, the process comprises c) separating the TDA from the aqueous mixture comprising TDA obtained in b).In some preferred embodiments of the process, the TDI comprising material of a) comprises, preferably is, a residue from TDI preparation, preferably a residue obtained or obtainable from a process for preparing TDI comprising phos- genation of TDA, more preferably a residue obtained or obtainable from a process for preparing TDI comprising phosgenation of TDA and, preferably subsequent, distillative removal of TDI (liquid TDI distillation residue) and / or more preferably a residue obtained or obtainable from a process for preparing TDI comprising phosgenation of TDA, subsequent distillative removal of TDI and subsequent drying (solid TDI distillation residue).In some preferred embodiments of the process, the material comprising a TDI based polyurethane comprises a TDI based polyurethane foam, preferably a TDI based polyurethane soft foam. A "TDI based polyurethane” is a polyurethane obtained or obtainable from the reaction of TDI with a isocyanate reactive, hydrogen containing, compound such as a polyol, wherein details on the reaction and the reactants are known to the skilled person. The expression "TDI polyurethane foam" as used herein generally refers to cellular products as obtained by reacting TDI with isocyanate reactive hydrogen containing compounds using foaming agents, and in particular includes cellular products obtained with water as reactive foaming agent (involving a reaction of water with isocyanate groups yielding urea linkages and carbon dioxide and producing polyurea-urethane foams); also here details regarding reactants and reaction parameters are known to the skilled person. A "TDI based polyurethane soft foam” is a foam that has a relatively low resistance to deformation (compressive stress at 10% compression according to DIN 53421S15 kPa).In some preferred embodiments of the process, at least 95 weight-% of the material(s) provided in a) consist of TDI comprising material and material comprising a TDI based polyurethane, wherein the total weight of the material(s) provided in a) are 100 weight-%. Preferably at least 96 weight-%, more preferably at least 97 weight-%, more preferably at least 98 weight-%, more preferably at least 99 weight-%, of the material(s) provided in (a) consist of TDI comprising material and optionally material comprising a TDI based polyurethane, wherein the total weight of the materials) provided in (a) are 100 weight-%. Preferably, at least 97 weight-%, more preferably at least 98 weight-%, more preferably at least 99 weight-% of the material(s) provided in (a) consist of residue from TDI preparation and optionally TDI polyurethane foam, more preferably at least 97 weight-%, more preferably at least 98 weight-%, more preferably at least 99 weight-% of the material(s) provided in (a) consist of TDI distillation residue and optionally TDI based polyurethane soft foam, wherein the total weight of the material(s) provided in (a) are 100 weight-%.In some preferred embodiments of the process, at last 5 weight-%, preferably at last 10 weight-%, more preferably at least 20 weight-%, more preferably at least 30 weight-%, more preferably at least 40 weight-%, more preferably at least 50 weight-%, more preferably at least 60 weight-%, more preferably at least 70 weight-%, more preferably at least 80 weight-%, more preferably at least 90 weight-%, of the material(s) provided in (a) consist of a TDI comprising material, preferably a residue from TDI preparation, more preferably a TDI distillation residue, wherein the totalweight of the material(s) provided in a) are 100 weight-%. In these preferred embodiments, it is preferred that the remaining amount up to 100 weight-% of the material(s) provided in (a) consists of material comprising a TDI based polyurethane, preferably a TDI based polyurethane foam, more preferably a TDI based polyurethane soft foam.In some preferred embodiments of the process, at least 95 weight-% o of the material(s) provided in a) consist of TDI comprising material, preferably of a residue obtained or obtainable from a process for preparing TDI comprising phosgenation of TDA, more preferably a residue obtained or obtainable from a process for preparing TDI comprising phosgenation of TDA and subsequent distillative removal of TDI (liquid TDI distillation residue) and / or a residue obtained or obtainable from a process for preparing TDI comprising phosgenation of TDA, subsequent distillative removal of TDI and subsequent drying (solid TDI distillation residue), wherein the total weight of the material(s) provided in a) are 100 weight-%. In these preferred embodiments, it is preferred that the remaining amount up to 100 weight-% of the material(s) provided in (a) consists of material comprising a TDI based polyurethane, preferably a TDI based polyurethane foam, more preferably a TDI based polyurethane soft foam.In some preferred embodiments of the process, contacting in b) is done in the presence of a basic catalyst. Preferably, the basic catalyst is selected from the group consisting of organic amine, preferably selected from substituted or unsubstituted pyridine, substituted or unsubstituted imidazole; primary amine; polyamine, preferably diamine, more preferably TDA; ammonia; alkali hydroxide; and mixtures of two or more thereof; wherein the one or more substituents are selected from hydrogen atom and Ci to C3 alkyl group; or the basic catalyst is selected from the group consisting of alkali hydroxide, TDA and mixtures of alkali hydroxide and TDA, more preferably selected from the group consisting of KOH, TDA and mixtures of KOH and TDA, more preferably the catalyst comprises at least TDA, more preferably the catalyst is TDA.In some preferred embodiments of the process, the weight-based ratio TDI comprising material : basic catalyst in step b) is in the range of from 1 :1 to 80:1, more preferably in the range of from 2:1 to 70:1, more preferably in the range of from 3:1 to 60:1.In some preferred embodiments of the process, the alcohol of b) is selected from the group consisting of methanol, ethanol, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, methylene glycol, 2-methyl-1 ,3-pro- panediol and mixtures of two or more thereof, wherein the alcohol of b) preferably comprises at least diethylene glycol, more preferably is diethylene glycol. The alcohol of b) is preferably an alcohol with a molecular weight of less than 500 g / mol, more preferably less than 300 g / mol.In some preferred embodiments of the process, the weight-based ratio TDI comprising material of a) : alcohol of b) in step b) is in the range of from 1 :50 to 50:1, more preferably in the range of from 1 :10 to 10:1, more preferably in the range of from 1 :5 to 5: 1 , more preferably in the range of from 1 :2 to 2: 1 .In some preferred embodiments of the process, the weight-based ratio TDI comprising material of a) : water in step b) is in the range of from 0.1 :1 to 10:1, more preferably in the range of from 0.8:1 to 8:1, more preferably in the range of from 0.9:1 to 6.5:1.In some preferred embodiments of the process, contacting in b) is done at a pressure in the range of from 0.8 to 100 bar, more preferably in the range of from 1 to 30 bar.In some preferred embodiments of the process, contacting in b) is done under autogenous pressure, preferably in a closed vessel, more preferably in an autoclave.In some preferred embodiments of the process, contacting in b) is done in the presence of a gaseous atmosphere, preferably in the presence of carbon dioxide.In some preferred alternative embodiments of the process, contacting in b) is done at a pressure in the range of from 0.8 to 1.2 bar (under ambient pressure), preferably in an open vessel. Preferably, contacting in b) is done in ambient atmosphere.In some preferred alternative embodiments of the process, contacting in b) is done under pressure maintenance, preferably in an open vessel and / or in the presence of a gaseous atmosphere, preferably in the presence of carbon dioxide. Pressure maintenance is ensured, for example, by addition and / or removal of carbon dioxide.In some preferred embodiments of the process, carbon dioxide generated in b) is removed. Removal of carbon dioxide, especially if contacting in b) is done under autogenous pressure, happens to a large extend directly when the respective vessel is depressurized. Remaining amounts of carbon dioxide may be removed in a subsequent water removal step.In some preferred embodiments of the process, contacting in b) is done at a temperature in the range of from 150 to 250 °C, preferably in the range of from 160 to 230 °C, more preferably in the range of from 170 to 220 °C, more preferably in the range of from 180 to 210 °C.In some preferred embodiments of the process, contacting in b) is done for a period of time in the range of from 10 minutes to 12 hours, preferably in the range of from 20 minutes to 8 hours, more preferably in the range of from 30 minutes to 5 hours.In some preferred embodiments of the process, c) comprises c.1) separation of liquid phase and solid phase of the aqueous mixture comprising TDA obtained in b), preferably by a physical separation method, thereby obtaining a liquid phase comprising TDA; c.2) separating the TDA from the liquid phase obtained in c.1).A physical separation method according to c.1) is one or more selected from the group of filtration, centrifugation. Separation according to c) or c.2) is preferably done by distillation, preferably by distillation under reduced pressure (< 1 bar). In said separation step, TDA is separated from water and the alcohol of b), thereby obtaining TDA.In some preferred embodiments, the process comprises, if the material provided in a) comprises a TDI based polyurethane, d) separating polyol released from the TDI based polyurethane and comprised in the liquid mixture obtained in b) and / or from the liquid phase obtained in c) or c.2).Separation in d) preferably happens by phase separation, wherein an organic phase comprising the polyol is formed, which separates from an aqueous phase, which comprises the TDA. The polyol released is preferably a polyol known to the person skilled in the art in connection with polyurethane chemistry, such as, in particular, polyether polyols, polyester polyols, polyether ester polyols and polyether carbonate polyols, wherein the term " polyol" comprises one polyol and mixtures of two or more thereof. A polyol released from the TDI based polyurethane preferably has a molecular weight of more than 500 g / mol.2ndaspect - combined processA second aspect of the invention is related to a combined process for preparing TDI and for recovering TDA, the process for preparing TDI comprisingA) introducing a liquid stream comprising at least TDA and a solvent into a reaction zone,B) subjecting the TDA comprised in the liquid stream to isocyanate forming conditions in the reaction zone, comprising introducing a phosgene-containing stream into the reaction zone, thereby forming TDI;C) removing from the reaction zone a liquid mixture comprising TDI;D) optionally separating remaining phosgene, optionally carbon dioxide, and optionally hydrochloride from the liquid mixture and removing the solvent, thereby obtaining a TDI comprising phase;E) separating TDI from the TDI comprising phase, preferably by distillation, obtaining a material, which still comprises TDI but is depleted of TDI compared to the TDI comprising phase (TDI comprising material); the process for recovering TDA comprisingF) contacting the TDI comprising material obtained in E) with an alcohol in an aqueous solution, thereby obtaining an aqueous mixture comprising TDA.Step D) is preferably carried out by distillation, wherein the solvent is removed and optional phosgene, optional carbon dioxide and optional hydrochloride are removed as well. In some preferred embodiments, step D) comprises several steps, wherein initially phosgene and hydrochloride and carbon dioxide are removed, together with parts of the solvent, and several further steps, wherein the remaining parts of the solvent are removed. The obtained TDI comprising phase is preferably (still) liquid.All details, embodiments, preferred embodiments and alternative preferred embodiments described above in the section related to the first aspect apply also for the combined process of the second aspect.In some preferred embodiments, the combined process comprisesX) addition of a TDI based polyurethane, preferably a TDI based polyurethane foam, more preferably a TDI based polyurethane soft foam to the TDI comprising material obtained in E) before F) and contacting in F) the TDI comprising material obtained in E) together with the TDI based polyurethane with the alcohol in an aqueous solution, thereby obtaining an aqueous mixture comprising TDA.Processes, equipment used and reaction conditions for TDI preparation are known to the skilled person and are described in detail in, for example, US 2004 / 0260117 A1 or EP 2 912 010 B1 . Solvents used are, for example, inert solvents selected from the group consisting of monochlorobenzene, toluene, o-or p-dichlorobenzene, trichlorobenzene, chlorotoluene, chloroxylene, chloroethylbenzene, chloronaphthalene, chlorodiphenyl, xylene, decahydronaphthalene, benzene and a mixture of two or more thereof. The processes can in principle be carried out either continuously or batchwise, with continuous operation being preferred. The process can be carried out in any apparatus suitable for a reaction with phosgene. Suitable reactors are, for example, stirred vessels, plug-flow reactor and reaction columns.Step F) of the combined process corresponds to step b) as described above in the section related to the first aspect. All details, embodiments, preferred embodiments and alternative preferred embodiments described above in the section related to the first aspect for step b) apply also for step F) of the combined process of the second aspect.In some preferred embodiments, the combined process comprises:G) Separating the TDA from the aqueous mixture comprising TDA obtained in F).Step G) of the combined process corresponds to step C) as described above in the section related to the first aspect. All details, embodiments, preferred embodiments and alternative preferred embodiments described above in the section related to the first aspect for step C) apply also for step G) of the combined process of the second aspect.In some preferred embodiments of the combined process, G) comprises:G.1) separation of liquid phase and solid phase of the aqueous mixture comprising TDA obtained in b), preferably by a physical separation method, thereby obtaining a liquid phase comprising TDA;G.2) Separating the TDA from the liquid phase obtained in G.1).Step G.1) of the combined process corresponds to step c.1) as described above in the section related to the first aspect. All details, embodiments, preferred embodiments and alternative preferred embodiments described above in the section related to the first aspect for step c.1) apply also for step G.1) of the combined process of the second aspect. Step G.2) of the combined process corresponds to step c.2) as described above in the section related to the first aspect; and by said step, TDA is obtained. All details, embodiments, preferred embodiments and alternative preferred embodiments described above in the section related to the first aspect for step c.2) apply also for step G.2) of the combined process of the second aspect.In some preferred embodiments, the process combined comprises, if a TDI based polyurethane is added in step X),H) separating polyol released from the TDI based polyurethane and comprised in the liquid mixture obtained in F) and / or from the liquid phase obtained in G.2).Step H) of the combined process corresponds to step d) as described above in the section related to the first aspect. All details, embodiments, preferred embodiments and alternative preferred embodiments described above in the section related to the first aspect for step d) apply also for step H) of the combined process of the second aspect.3rdaspect - TDA obtained or obtainableA third aspect of the invention relates to TDA obtained or obtainable from the process of the first aspect or from the combined process of the second aspect.All details, embodiments, preferred embodiments and alternative preferred embodiments described above in the section related to the first aspect and in the section related to the second aspect apply also for the third aspect.4thaspect - UseA fourth aspect of the invention relates to the use of the TDA of the third aspect for the preparation of TDI.All details, embodiments, preferred embodiments and alternative preferred embodiments described above in the section related to the first aspect, the section related to the second aspect and in the section related to the third aspect apply also for the fourth aspect.5thaspect - Method for preparing TDIA fifth aspect of the invention is directed to a method for preparing TDI comprisingI) providing TDA of the third aspect;II) preparing TDI from the TDA provided in I), preferably by phosgenation.All details, embodiments, preferred embodiments and alternative preferred embodiments described above in the section related to the first aspect, the section related to the second aspect, the section related to the third aspect and in the section related to the fourth aspect apply also for the fifth aspect.According to a further aspect, the present invention is directed to a process, preferably to the process as described above or the combined process as described above, comprising the step of converting the TDA obtainable or obtained by the process described herein or the TDA obtainable or obtained by the combined process as described herein or the polyol obtainable or obtained by the process described herein or the polyol obtainable or obtained by the combined process as described herein or a chemical material obtainable or obtained by the process described herein or a chemical material obtainable or obtained by the combined process described herein or the TDI obtainableor obtained by the method described herein or a chemical material obtainable or obtained by the method described herein to obtain a product Q.Preferably, the product Q is selected from: building block or monomer; or polymer, preferably polymer A, polymer composition, preferably polymer composition A, or polymer product, preferably polymer product A; or cleaning polymer, cleaning surfactant, descaling compound, cleaning biocide or composition or formulation thereof; or agrochemical composition, agrochemical formulation auxiliary or agrochemically active ingredient; or active pharmaceutical ingredient or intermediate thereof, pharmaceutical excipient, animal feed additive, human food additive, dietary supplements, aroma chemical or aroma composition; or aqueous polymer dispersion, preferably polyurethane or polyurethane - poly(meth)acrylate hybrid polymer dispersion, emulsion, binder for paper and fiber coatings, UV-curable acrylic polymer for hot melts and coatings polyisocyanates, hyperbranched polyester polyol, polymeric dispersant for inorganic binder compositions, unsaturated polyester polyol or 100% curable composition; or cosmetic surfactant, emollient, wax, cosmetic polymer, UV filter, further cosmetic ingredient or composition or formulation thereof; or polymer B, polymer composition B, coating composition, other functional composition, foil, molded body, coating or coated substrate.Regarding this process from which the product Q is obtained, it is preferred: that the content of the TDA or the polyol or the TDI or the chemical material in the product Q is 1 weight-% or more, preferably 2 weight-% or more, more preferably 5 weight-% or more, more preferably 15 weight-% or more, more preferably 30 weight-% or more, more preferably 40 weight-% or more, more preferably 60 weight-% or more, more preferably 80 weight-% or more, more preferably 90 weight-% or more, more preferably 95 weight-% or more; and / or that the content of the TDA or the polyol or the TDI or the chemical material in the product Q is 100 weight-% or less, preferably 95 weight-% or less, more preferably 90 weight-% or less, more preferably 50 weight-% or less, more preferably 25 weight-% or less, more preferably 10 weight-% or less; and wherein it is more preferred that the respective content is determined based on identity preservation and / or segregation and / or mass balance and / or book and claim chain of custody models, preferably based on mass balance, preferably the International Sustainability and Carbon Certification (ISCC) standard.The publication Prior Art Disclosure; Issue 684; paragraphs

[1000] to

[8005] ; ISSN: 2198-4786; published: February 12, 2024 will be regarded as Reference RF1 , which is incorporated herein by reference in its entirety. Preferably, the product Q is a product as described in Reference RF1 ; paragraphs

[1000] to

[8005] , Preferably, the process described herein is further a process for the production of a product.The converting step to obtain the product Q preferably comprises one or more step(s) as described below and can be performed by conventional methods well known to a person skilled in the art. The converting step preferably comprises one or more step(s) selected from: recycling, preferably depolymerizing, gasifying, pyrolyzing, and / or steam cracking; and / or purifying, preferably crystallizing, (solvent) extracting, distilling, evaporating, hydrotreating, absorbing, adsorbing and / or subjecting to ion exchanger; and / or assembling, preferably foaming, synthesizing, chemical conversion, chemically transforming, polymerizing and / or compounding; and / or forming, preferably foaming, extruding and / or molding; and / or finishing, preferably coating and / or smoothing.In addition, the one or more step(s) are described in detail in Reference RF1; paragraphs

[1000] to

[8005] ,The term "monomer”, as used in the context of the product Q herein, comprises molecules, which can react with each other to form polymer chains by polymerization. The monomer is preferably selected from the group consisting of (meth)acrylic acid, salts of (meth)acrylic acid; in particular sodium, potassium and zinc salts; (meth)acrolein and (meth)acrylates. (Meth)acrylates comprising 1 to 22 carbon atoms are preferred, in particular comprising 1 to 8 carbon atoms. The terms (meth)acrylic acid, (meth)acrolein or (meth)acrylate relate to acrylic acid, acrolein or acrylate and also to methacrylic acid, methacrolein or methacrylate, where applicable. Further, the monomer can be selected from hexamethylenediamine (HMD) and adipic acid.The building block can further be an intermediate compound. The term "intermediate compound”, as used in the context of the product Q herein, comprises organic reagents, which are applied for formation of compounds with higher molecular complexity. The intermediate compound can be selected for example from the group consisting of phosgene, polyisocyanates and propylene oxide. The polyisocyanates are in particular aromatic di- and polyisocyanates, preferably toluene diisocyanate (TDI) and / or diphenylmethane diisocyanate (MDI).The building block and the monomer and typical converting step(s) to obtain the building block or monomer are described in more detail in paragraphs

[1000] to

[1012] of Reference RF1.The term "polymer A”, as used in the context of the product Q herein, comprises thermoplastic, e.g., polyamide or thermoplastic polyurethane, thermoset, e.g., polyurethane, elastomer, e.g., polybutadiene, or a copolymer or a mixture thereof and is defined in more detail in paragraphs

[2001] to

[2007] of Reference RF1 .The term "polymer composition A”, as used in the context of the product Q herein, comprises all compositions comprising a polymer as described above and one or more additive(s), e.g. reinforcement, colorant, modifier and / or flame retardant, and is defined in more detail in paragraph

[2008] of Reference RF1.The term "polymer product A”, as used in the context of the product Q herein, comprises any product comprising the polymer A and / or polymer composition A as described above and is defined in more detail in paragraphs

[2009] andThe step(s) to obtain the polymer, preferably polymer A, polymer composition, preferably polymer composition A or polymer product, preferably polymer product A is / are described in more detail in paragraph

[2011] of Reference RF1 .The term "industrial use polymer”, as used in the context of the product Q herein, comprises rheology, polycarboxylate, alkoxylated polyalkylenamine, alkoxylated polyalkylenimine, polyether-based, dye inhibition and soil release cleaning polymers defined in more detail in paragraphs

[3035] to

[3044] of Reference RF1. The term "industrial use surfactant”, as used in the context of the product Q herein, comprises non-ionic, anionic and amphoteric industrial use surfactants defined in more detail in paragraphs

[3008] to

[3034] of Reference RF1. The term "industrial use descaling compound”, as used in the context of the product Q herein, comprises non-phosphate based builders (NPB) and phosphonates (CoP) described in more detail in paragraphs

[3001] to

[3005] of Reference RF1. The term "industrial use biocide”, as used in the context of the product Q herein, refers to a chemical compound that kills microorganisms or inhibits their growth or reproduction defined in more detail in paragraphs

[3006] to

[3007] of Reference RF1. The term "industrial use solvent”, as used in the context of the product Q herein, comprises alkyl amides, alkyl lactamides, alkyl esters, lactate esters, alkyl diester, cyclic alkyl diester, cyclic carbonates, aromatic aldehydes and aromatic esters defined in more detail in paragraphs

[3045] to

[3055] of Reference RF1. The term "industrial use dispersant”, as used in the context of the product Q herein, comprises anionic and non-ionic industrial use dispersants defined in more detail in paragraphs

[3056] to

[3058] of Reference RF1 . The term "composition and / or formulation thereof' with reference to the industrial use polymers, industrial use surfactants, descaling compounds and / or industrial use biocides refers to industrial use compositions and / or institutional use products and / or fabric and home care products and / or personal care products defined in more detail in paragraph

[3059] of Reference RF1 . The converting step(s) to obtain the industrial use polymer, industrial use surfactant, descaling compound and / or industrial use biocide are defined in more detail in paragraph

[3060] of Reference RF1. The converting steps to obtain the industrial use composition or formulation of the industrial use polymer, industrial use surfactant, descaling compound and / or industrial use biocide are defined in more detail in paragraph

[3061] of Reference RF1.The term "agrochemical composition”, as used in the context of the product Q herein, typically relates to a composition comprising an agrochemically active ingredient and at least one agrochemical formulation auxiliary. Examples of agrochemical compositions, active ingredients and auxiliaries are described in more detail in Reference RF1, paragraph

[4001] ,The agrochemical composition may take the form of any customary formulation. The agrochemical compositions are prepared in a known manner, e.g. described by Mollet and Grubemann, Formulation technology, Wiley VCH, Weinheim, 2001; or Knowles, New developments in crop protection product formulation, Agrow Reports DS243, T&F Informa, London, 2005. The converting step(s) to obtain the agrochemically active ingredients and auxiliaries may be conducted in analogy to the production step(s) of their analogues that are based on petrochemicals or other precursors that are not gained by recycling processes. In addition, conversion to compounds mentioned in sections "Polymer” and "Cosmetic surfactant, emollient, wax, cosmetic polymer, UV filter, further cosmetic ingredient or compositions or formulations thereof' may be performed as described in these sections as well as the respective paragraphs in Reference RF1.The term active pharmaceutical ingredients and / or intermediates thereof, as used in the context of the product Q herein, comprises substances that provide pharmacological activity or other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of disease, or to affect the structure or any function of the body. Intermediates thereof are isolated products that are generated during a multi-step route of synthesis of an active pharmaceutical ingredient. The term pharmaceutical excipients, as used in the context of the product Q herein, comprises compounds or compound mixtures used in compositions for various pharmaceutical applications, which are not substantially pharmaceutically active on itself. Active pharmaceutical ingredients and / or intermediates thereof and pharmaceutical excipients are defined in more detail in paragraph

[5001] of Reference RF1.The converting step(s) to obtain the active pharmaceutical ingredients and / or intermediates thereof and pharmaceutical excipients may comprise one or more synthesis steps and can be performed by conventional synthesis and techniques well known to a person skilled in the art.The terms animal feed additives, human food additives, dietary supplements, as used in the context of the product Q herein, comprises Vitamins, Pro-Vitamins and active metabolites thereof including intermediates and precursors, especially Vitamin A, B, E, D, K and esters thereof, like acetate, propionate, palmitate esters or alcohols thereof like retinol or salts thereof and any combinations thereof; Tetraterpenes, especially isoprenoids like carotenoids and xanthophylls including their intermediates and precursors as well as mixtures and derivates thereof, especially beta carotene, Canthaxanthin, Citranaxanthin, Astaxanthin, Zeaxanthin, Lutein, Lycopene, Apo-carotenoids, and any combinations thereof; organic acids, especially formic acid, propionic acid and salts thereof, such as sodium, calcium or ammonium salts, and any combinations thereof, such as but not limited to mixtures of formic acid and sodium formiate, propionic acid and ammonium propionate, formic acid and propionic acid, formic acid and sodium formiate and propionic acid, propionic acid and sodium propionate and formic acid and sodium formiate; glycerides of carboxylic acids and short and medium chain fatty acids, conjugated linoleic acids, such as omega-6 fatty acid (C18:2) methyl ester and 1 ,2-propandiol and beverage stabilizers, such as polyvinylpyrrolidone-polymer or polyvinylimidazole / polyvinylpyr- rolidone-copolymer. Animal feed additives, human food additives and dietary supplements are defined in more detail in paragraph

[5002] of Reference RF1.The converting step(s) to obtain the animal feed additives, human food additives, dietary supplements may comprise one or more synthesis steps and can be performed by conventional synthesis and techniques well known to a person skilled in the art.The terms aroma chemical and aroma composition as used in the context of the product Q herein, comprise a volatile organic substance with a molecular weight between 70-250 g / mol comprising a functional group with a carbon skeleton of C5-C16 carbon atoms comprising linear, branched, cyclic, for example with a ring size of C5-C18, bicyclic or tricyclic aliphatic chains and but not necessarily one or more unsaturated structural elements like double bonds, triple bonds, aromatics or heteroaromatics and preferably the one or more additional functional groups are selected from alcohol, ether, ester, ketone, aldehyde, acetal, carboxylic acid, nitrile, thiol, amine. In one aspect, the aroma chemical is a terpene-based aroma chemical, for example selected from monoterpenes and monoterpenoids, sesquiterpenes and sesquiterpenoids, diterpenes, triterpenes or tetraterpenes. Aroma chemicals can be combined with further aromachemicals to give an aroma composition. Aroma chemicals and aroma compositions are defined in more detail in paragraph

[5003] of Reference RF1.The converting step(s) to obtain the aroma chemical and aroma composition may comprise one or more synthesis steps and can be performed by conventional synthesis and techniques well known to a person skilled in the art.The term "aqueous polymer dispersion”, as used in the context of the product Q herein, comprises aqueous compositions) comprising dispersed polymer(s) and is defined in more detail in the section

[6001] entitled "aqueous polymer dispersion” of Reference RF1 . The dispersed polymer(s) may be selected from acrylic emulsion polymer(s), styrene acrylic emulsion polymer(s), styrene butadiene dispersion(s), aqueous dispersion(s) comprising composite particles, acrylate alkyd hybrid dispersion(s), polyurethane(s) (including UV-curable polyurethanes) and polyurethane - poly(meth)acrylate hybrid polymer(s). The term "emulsion polymer”, as used in the context of the product Q herein, comprises polymer(s) made by free-radical emulsion polymerization. Aqueous polyurethane dispersion(s) are defined in more detail in the section

[6002] entitled "Polyurethane dispersions” of Reference RF1. UV-curable polyure- thane(s) is / are defined in more detail in the section

[6017] of Reference RF1. Polyurethane - poly(meth)acrylate hybrid polymer(s) is / are defined in more detail in the section

[6016] of Reference RF1.The term "polymeric dispersant”, as used in the context of the product Q herein, comprises preferably polymer(s) comprising polyether side chain, in particular polycarboxylate ether polymer(s) and polycondensation product(s) defined in more detail in paragraph

[6020] entitled "Polymeric dispersant” of Reference RF1.The converting (polymerization) step(s) to obtain the aqueous polymer dispersion(s) comprising emulsion polymer(s) is / are defined in more detail in the section

[6003] entitled "Emulsion polymerization” of Reference RF1.The converting (polymerization) step(s) to obtain the aqueous polyurethane dispersion(s) is / are defined in more detail in the section

[6014] entitled "Process for the preparation of aqueous polyurethane dispersions” and section [6017)] entitled "Aqueous UV-curable polyurethane dispersions, their preparation and use and compositions containing them” of Reference RF1 .Composition(s) and uses of aqueous polymer dispersion(s) and of polymeric dispersant(s) are defined in more detail in the following sections of Reference RF1 : section

[6004] entitled "Uses of aqueous polymer dispersions”, section

[6005] entitled "Binders for architectural and construction coatings” section

[6006] entitled "Binders for paper coating” section

[6007] entitled "Binders for fiber bonding” section

[6008] entitled "Adhesive polymers and adhesive compositions” section

[6015] entitled "Aqueous polyurethane dispersions suitable for use in coating compositions” section

[6016] entitled "Aqueous polyurethane - poly(meth)acrylate hybride polymer dispersions suitable for use in coating compositions” section

[6017] entitled "Aqueous UV-curable polyurethane dispersions, their preparation and use and compositions containing them”section

[6018] entitled "Inorganic binder compositions comprising polymeric dispersants and their use”

[6019] 100% curable coating compositionsUV-crosslinkable poly(meth)acrylate(s) and its / their uses are defined in more detail in section

[6009] entitled "UV- crosslinkable poly(meth)acrylates for use in UV-curable solvent-free hotmelt adhesives and their use for making pressure-sensitive self-adhesive articles” of Reference RF1.Polyisocyanate(s), composition(s) comprising them and their uses are defined in more detail in section

[6010] entitled "Polyisocyanates” of Reference RF1.Hyperbranched polyester polyol(s) and its / their uses are defined in more detail in section

[6011] entitled "Organic solvent based hyperbranched polyester polyols suitable for use in coating compositions” of Reference RF1. The converting step(s) to obtain the hyperbranched polyester polyols is / are defined in more detail in the section

[6012] entitled "Preparation of organic solvent based hyperbranched polyester polyols” of Reference RF1 . Coating compositions) comprising hyperbranched polyester polyol(s), polyisocyanate(s) and additive(s) and substrate(s) coated therewith are defined in more detail in section

[6013] entitled "Organic solvent based two component coating compositions comprising hyperbranched polyester polyols and polyisocyanates” of Reference RF1.Unsaturated polyester polyol(s), solvent-based coating composition(s) comprising said unsaturated polyester pol- yol(s) and substrate(s) for coating with said coating composition(s) are defined in more detail in section

[6018] entitled "Organic solvent based coating composition comprising unsaturated polyester polyols” of Reference RF1. 100% curable coating composition(s) is / are defined in more detail in section

[6019] of Reference RF1.Polymeric dispersant(s) for inorganic binder compositions is / are defined in more detail in section

[6020] of Reference RF1. The inorganic binder composition(s) comprising the polymeric dispersants and their use are defined in more detail in section

[6021] of Reference RF1. The converting step(s) to obtain the polymeric dispersant(s) are defined in more detail in section

[6020] of Reference RF1 . The term "inorganic binder composition” comprising the polymeric dispersant(s), as used in the context of the product Q herein, comprises preferably in particular hydraulically setting compositions and compositions comprising calcium sulfate and is defined in more detail in section

[6021] of Reference RF1 entitled "Inorganic binder compositions comprising the polymeric dispersant and their use”. Specific building material formulation(s) comprising polymeric dispersant(s) or building product(s) produced by a building material formulation comprising a polymeric dispersant are disclosed in more detail in section

[6021] of Reference RF1.The term "cosmetic surfactant”, as used in the context of the product Q herein, comprises non-ionic, anionic, cationic and amphoteric surfactants and is defined in more detail in paragraph

[7002] of Reference RF1. The term "emollient”, as used in the context of the product Q herein, refers to a chemical compound used for protecting, moisturizing, and / or lubricating the skin and is defined in more detail in paragraph

[7003] of Reference RF1. The term "wax”, as used in the context of the product Q herein, comprises pearlizers and opacifiers and is defined in more detail in para-graph

[7004] of Reference RF1 . The term "cosmetic polymer”, as used in the context of the product Q herein, comprises any polymer that can be used as an ingredient in a cosmetic formulation and is defined in more detail in paragraph

[7005] of Reference RF1 . The term "UV filter”, as used in the context of the product Q herein, refers to a chemical compound that blocks or absorbs ultraviolet light and is defined in more detail in paragraph

[7006] of Reference RF1 . The term "further cosmetic ingredient”, as used in the context of the product Q herein, comprises any ingredient suitable for making a cosmetic formulation. Several sources disclose cosmetically acceptable ingredients. E.g. the database Cosing on the internet pages of the European Commission discloses cosmetic ingredients and the International Cosmetic Ingredient Dictionary and Handbook, edited by the Personal Care Products Council (PCPC), discloses cosmetic ingredients. The term "composition and / or formulation thereof' with reference to the cosmetic surfactant, emollient, wax, cosmetic polymer, UV filter and / or further cosmetic ingredient refers to personal care and / or cosmetic compositions or formulations defined in more detail in paragraph

[7007] of Reference RF1 . The converting step(s) to obtain the cosmetic surfactant, emollient, wax, cosmetic polymer, UV filter or further cosmetic ingredient is / are defined in more detail in paragraph

[7008] of Reference RF1.The terms “polymer B”, “polymer composition B”, “coating composition”, “other functional composition”, “foil”, “molded body", “coating” and “coated substrate” are well known to the person skilled in the art and are defined in more detail from paragraph

[8000] to

[8005] of Reference RF1.The present invention is further illustrated by the following set of embodiments and combinations of embodiments resulting from the dependencies and back-references as indicated. In particular, it is noted that in each instance where a range of embodiments is mentioned, for example in the context of a term such as "The process of any one of embodiments 1 to 4", every embodiment in this range is meant to be explicitly disclosed for the skilled person, i.e. the wording of this term is to be understood by the skilled person as being synonymous to "The process of any one of embodiments 1, 2, 3 and 4". Further, it is explicitly noted that the following set of embodiments represents a suitably structured part of the general description directed to preferred aspects of the present invention, and, thus, suitably supports, but does not represent the claims of the present invention.1 . Process for recovering toluene diamine (TDA) from a toluene diisocyanate (TDI) comprising material comprising a) providing a TDI comprising material and optionally a material comprising a TDI based polyurethane; b) contacting the material(s) provided in a) with an alcohol in an aqueous solution, thereby obtaining an aqueous mixture comprising TDA.2. The process of embodiment 1 comprising c) separating the TDA from the aqueous mixture comprising TDA obtained in b).3. The process of embodiment 1 or 2, wherein the TDI comprising material of a) comprises, preferably is, a residue from TDI preparation, preferably a residue obtained or obtainable from a process for preparing TDI comprising phosgenation of TDA, more preferably a residue obtained or obtainable from a process for preparingTDI comprising phosgenation of TDA and, preferably subsequent, distillative removal of TDI (liquid TDI distillation residue) and / or more preferably a residue obtained or obtainable from a process for preparing TDI comprising phosgenation of TDA, subsequent distillative removal of TDI and subsequent drying (solid TDI distillation residue). The process of any one of embodiments 1 to 3, wherein the material comprising a TDI based polyurethane comprises a TDI based polyurethane foam, preferably a TDI based polyurethane soft foam. The process of any one of embodiments 1 to 4, wherein at least 95 weight-% of the material(s) provided in a) consist of TDI comprising material and material comprising a TDI based polyurethane, wherein the total weight of the material(s) provided in a) are 100 weight-%. The process of any one of embodiments 1 to 5, wherein at last 5 weight-%, preferably at last 10 weight-%, more preferably at least 20 weight-%, more preferably at least 30 weight-%, more preferably at least 40 weight-%, more preferably at least 50 weight-%, more preferably at least 60 weight-%, more preferably at least 70 weight-%, more preferably at least 80 weight-%, more preferably at least 90 weight-%, of the materials) provided in (a) consist of a TDI comprising material, preferably a residue from TDI preparation, more preferably a TDI distillation residue, wherein the total weight of the material(s) provided in a) are 100 weight- %. The process of any one of embodiments 1 to 6, wherein at least 95 weight-% o of the material(s) provided in a) consist of TDI comprising material, preferably of a residue obtained or obtainable from a process for preparing TDI comprising phosgenation of TDA, more preferably a residue obtained or obtainable from a process for preparing TDI comprising phosgenation of TDA and subsequent distillative removal of TDI (liquid TDI distillation residue) and / or a residue obtained or obtainable from a process for preparing TDI comprising phosgenation of TDA, subsequent distillative removal of TDI and subsequent drying (solid TDI distillation residue), wherein the total weight of the material(s) provided in a) are 100 weight-%. The process of any one of embodiments 1 to 7, wherein contacting in b) is done in the presence of a basic catalyst. The process of embodiment 8, wherein the basic catalyst is selected from the group consisting of organic amine, preferably selected from substituted or unsubstituted pyridine, substituted or unsubstituted imidazole; primary amine; polyamine, preferably diamine, more preferably TDA; ammonia; alkali hydroxide; and mixtures of two or more thereof; wherein the one or more substituents are selected from hydrogen atom and Ci to C3 alkyl group. The process of embodiment 8 or 9, wherein the basic catalyst is selected from the group consisting of alkali hydroxide, TDA and mixtures of alkali hydroxide and TDA, more preferably selected from the group consistingof KOH, TDA and mixtures of KOH and TDA, more preferably the catalyst comprises at least TDA, more preferably the catalyst is TDA.11 . The process of any one of embodiments 8 to 10, wherein the weight-based ratio TDI comprising material : basic catalyst in step b) is in the range of from 1 :1 to 80:1, preferably in the range of from 2:1 to 70:1, more preferably in the range of from 3:1 to 60:1.12. The process of any one of embodiments 1 to 11, wherein the alcohol of b) is selected from the group consisting of methanol, ethanol, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, methylene glycol, 2-methyl-1 ,3-propanediol and mixtures of two or more thereof, wherein the alcohol of b) preferably comprises at least diethylene glycol, more preferably is diethylene glycol.13. The process of any one of embodiments 1 to 12, wherein the weight-based ratio TDI comprising material of a) : alcohol of b) in step b) is in the range of from 1 :50 to 50: 1 , preferably in the range of from 1 : 10 to 10: 1 , more preferably in the range of from 1 :5 to 5:1, more preferably in the range of from 1 :2 to 2:1.14. The process of any one of embodiments 1 to 13, wherein the weight-based ratio TDI comprising material of a) : water in step b)is in the range of from 0.1 :1 to 10:1, preferably in the range of from 0.8:1 to 8:1, more preferably in the range of from 0.9: 1 to 6.5.1 .15. The process of any one of embodiments 1 to 14, wherein contacting in b) is done at a pressure in the range of from 0.8 to 100 bar, preferably in the range of from 1 to 30 bar.16. The process of any one of embodiments 1 to 15, wherein contacting in b) is done under autogenous pressure, preferably in a closed vessel, more preferably in an autoclave.17. The process of any one of embodiments 1 to 16, wherein contacting in b) is done in the presence of a gaseous atmosphere, preferably in the presence of carbon dioxide.18. The process of any one of embodiments 1 to 14, wherein contacting in b) is done at a pressure in the range of from 0.8 to 1.2 bar (under ambient pressure), preferably in an open vessel.19. The process of embodiment 18, wherein contacting in b) is done in ambient atmosphere.20. The process of any one of embodiments 1 to 14, wherein contacting in b) is done under pressure maintenance, preferably in an open vessel and / or in the presence of a gaseous atmosphere, preferably in the presence of carbon dioxide.The process of any one of embodiments 1 to 20, preferably of any one of embodiments 1 to 16 or 17 to 19, wherein carbon dioxide generated in b) is removed. The process of any one of embodiments 1 to 20, wherein contacting in b) is done at a temperature in the range of from 150 to 250 °C, preferably in the range of from 160 to 230 °C, more preferably in the range of from 170 to 220 °C, more preferably in the range of from 180 to 210 °C. The process of any one of embodiments 1 to 22, wherein contacting in b) is done for a period of time in the range of from 10 minutes to 12 hours, preferably in the range of from 20 minutes to 8 hours, more preferably in the range of from 30 minutes to 5 hours. The process of any one of embodiments 2 to 23, wherein c) comprises c.1) separation of liquid phase and solid phase of the aqueous mixture comprising TDA obtained in b), preferably by a physical separation method, thereby obtaining a liquid phase comprising TDA; c.2) separating the TDA from the liquid phase obtained in c.1). The process of any one of embodiments 2 to 24, comprising if the material provided in a) comprises a TDI based polyurethane, d) separating polyol released from the TDI based polyurethane and comprised in the liquid mixture obtained in b) and / or from the liquid phase obtained in c.2). A combined process for preparing TDI and for recovering TDA, the process for preparing TDI comprisingA) introducing a liquid stream comprising at least TDA and a solvent into a reaction zone,B) subjecting the TDA comprised in the liquid stream to isocyanate forming conditions in the reaction zone, comprising introducing a phosgene-containing stream into the reaction zone, thereby forming TDI;C) removing from the reaction zone a liquid mixture comprising TDI;D) optionally separating remaining phosgene, optionally carbon dioxide, and optionally hydrochloride from the liquid mixture and removing the solvent, thereby obtaining a TDI comprising phase;E) separating TDI from the TDI comprising phase, preferably by distillation, obtaining a material, which still comprises TDI but is depleted of TDI compared to the TDI comprising phase (TDI comprising material); the process for recovering TDA comprisingF) contacting the TDI comprising material obtained in E) with an alcohol in an aqueous solution, thereby obtaining an aqueous mixture comprising TDA. The combined process of embodiment 26 comprisingX) addition of a TDI based polyurethane, preferably a TDI based polyurethane foam,more preferably a TDI based polyurethane soft foam to the TDI comprising material obtained in E) before F) and contacting in F) the TDI comprising material obtained in E) together with the TDI based polyurethane with the alcohol in an aqueous solution, thereby obtaining an aqueous mixture comprising TDA.28. TDA obtained or obtainable from a process of any one of embodiments 1 to 25 or from the combined process of embodiment 26 or 27.29. Use of the TDA of embodiment 28 for the preparation of TDI.30. Method for preparing TDI comprisingI) providing TDA of embodiment 28;II) preparing TDI from the TDA provided in I), preferably by phosgenation.31 . A process, preferably according to any one of embodiments 1 to 25 or 26 to 27, comprising the step of converting the TDA obtainable or obtained by the process according to any one of embodiments 1 to 25 or the TDA obtainable or obtained by the combined process according to embodiment 26 or 27, or the polyol obtainable or obtained by the process according to any one of embodiments 1 to 25 or the polyol obtainable or obtained by the combined process according to embodiment 26 or 27 or a chemical material obtainable or obtained by the process according to any one of embodiments 1 to 25 or a chemical material obtainable or obtained by the combined process according to embodiment 26 or 27 or the TDI obtainable or obtained by the method according to embodiment 30 or a chemical material obtainable or obtained by the method according to embodiment 30 to obtain a product Q.32. The process according to embodiment 31 , wherein the product Q is selected from: building block or monomer; or polymer, preferably polymer A, polymer composition, preferably polymer composition A, or polymer product, preferably polymer product A; or cleaning polymer, cleaning surfactant, descaling compound, cleaning biocide or composition or formulation thereof; or agrochemical composition, agrochemical formulation auxiliary or agrochemically active ingredient; or active pharmaceutical ingredient or intermediate thereof, pharmaceutical excipient, animal feed additive, human food additive, dietary supplements, aroma chemical or aroma composition; or aqueous polymer dispersion, preferably polyurethane or polyurethane - poly(meth)acrylate hybrid polymer dispersion, emulsion, binder for paper and fiber coatings, UV-curable acrylic polymer for hot melts and coatings polyisocyanates, hyperbranched polyester polyol, polymeric dispersant for inorganic binder compositions, unsaturated polyester polyol or 100% curable composition; or cosmetic surfactant, emollient, wax, cosmetic polymer, UV filter, further cosmetic ingredient or composition or formulation thereof; orpolymer B, polymer composition B, coating composition, other functional composition, foil, molded body, coating or coated substrate.33. The process according to embodiment 31 or 32, wherein the content of the TDA or the polyol or the TDI or the chemical material in the product 0 is 1 weight- % or more, preferably 2 weight-% or more, more preferably 5 weight-% or more, more preferably 15 weight-% or more, more preferably 30 weight-% or more, more preferably 40 weight-% or more, more preferably 60 weight-% or more, more preferably 80 weight-% or more, more preferably 90 weight-% or more, more preferably 95 weight-% or more; and / or wherein the content of the TDA or the polyol or the TDI or the chemical material in the product O is 100 weight-% or less, preferably 95 weight-% or less, more preferably 90 weight-% or less, more preferably 50 weight-% or less, more preferably 25 weight-% or less, more preferably 10 weight-% or less; and preferably wherein the content is determined based on identity preservation and / or segregation and / or mass balance and / or book and claim chain of custody models, preferably based on mass balance, preferably the International Sustainability and Carbon Certification (ISCC) standard.The present invention is further illustrated by the following reference examples, comparative examples, and examples.ExamplesChemicalsExample 1 : TDA recovery using aqueous KOHAn autoclave (volume 0.3 liter) was filled with 81 g of a dry residue from TDI production (TDI residue, = solid sample). 70 g diethylene glycol (DEG), 3.23 g of an aqueous KOH solution (50 weight-%) and 12 g water were added. The autoclave was sealed, heated to 200°C under stirring and kept under these conditions for 4 h. Afterwards, the reaction mixture was cooled down to 80°C and the reactor was depressurized.About 140 g of the autoclave content were removed from the autoclave (reaction mass). The autoclave was rinsed with acetone. Reaction mass removed was filtered via a pressurized filter. 13.7 g of a solid were obtained, i.e. about 17 weight-% of the initial amount of TDI residue remained solid, whereas about 83 weight-% were liquefied.114 g of the filtrate contained, as determined by GC analytic, a content of 17.5 weight-% 2,4-TDA and 3.0 weight-% 2,6-TDA, corresponding in sum to 23.3 g TDA. Autoclave and filter were rinsed with acetone, the resulting acetone containing rinsing solution had a weight of about 115 g. Said rising solution was also analysed by GC analytic and determined to comprise 1 .3 weight-% 2,4-TDA and 0.3 weight-% 2,6-TDA, corresponding to in sum 1 .9 g TDA. The overall amount of TDA from the filtrate and the rising solution was thus 25.2 g, corresponding to 31 g TDA per 100 g TDI residue; Example details and results are summarized in Table 1 below.Example 2: TDA recovery using TDAAn autoclave (volume 0.3 liter) was filled with 50 g of a dry residue from TDI production (TDI residue, = solid sample). 50 g diethylene glycol (DEG), 15 g TDA (80 weight-% 2,4-TDA, 20 weight-% 2,6-TDA) and 50 g water were added. The autoclave was sealed, heated to 200°C under stirring and kept under these conditions for 4 h. Afterwards, the reaction mixture was cooled down to 80°C and the reactor was depressurized.About 145 g of the autoclave content were removed from the autoclave(reaction mass). The reaction mass was filtered via a pressurized filter. 0.7 g of a solid were obtained, i.e. about 1.4 weight-% of the initial amount of TDI residue remained solid, whereas about 98.4 weight-% were liquefied.134 g of the filtrate contained, as determined by GC analytic, a content of 20.4 weight-% 2,4-TDA and 4.1 weight-% 2,6-TDA, corresponding to in sum 32,8 g TDA. Autoclave and filter were rinsed with acetone, the resulting acetone containing rinsing solution had a weight of about 137.75 g. Said rising solution was also analysed by GC analytic and determined to comprise 2.4 weight-% 2,4-TDA and 0.4 weight-% 2,6-TDA, corresponding to in sum 3.9 g TDA. The overall amount of TDA from the filtrate and the rising solution minus the initially added TDA of 15 g was thus 21.9 g, corresponding to 43.5 g TDA per 100 g TDI residue; Example details and results are summarized in Table 1 below.Example 3: TDA recovery from mixed sample using TDAAn autoclave (volume 0.3 liter) was filled with 18 g of a dry residue from TDI production (TDI residue) and 18 g of a TDI based PU soft foam (TDI residue + TDI based PU soft foam = solid sample). 36 g diethylene glycol (DEG), 11 g TDA (80 weight-% 2,4-TDA, 20 weight-% 2,6-TDA) and 36 g water were added. The autoclave was sealed, heated to 200°C under stirring and kept under these conditions for 4 h. Afterwards, the reaction mixture was cooled down to 80°C and the reactor was depressurized.About 105.8 g of the autoclave content were removed from the autoclave (reaction mass). The reaction mass was filtered via a pressurized filter. 1 .06 g of a solid were obtained, i.e. about 5.9 weight-% of the initial amount of solids (TDI residue + TDI based PU soft foam) remained solid, whereas about 94.1 weight-% were liquefied.The filtrate of about 95.7 g was phase separated and a polyol containing upper phase of about 11 .6 g and a TDA containing lower phase of about 84 g were obtained. TDA content in both phases was determined by HPLC and was 15 weight-% in the upper phase (2.6 weight-% 2,6-TDA and 12.4 weight-% 2,4-TDA) and 20 weight-% in der lower phase (3.4 weight-% 2,6-TDA and 16.6 weight-% 2,4-TDA) respectively, corresponding to 1 .75 g and 16.8 g TDA.Autoclave and filter were rinsed with acetone, the resulting acetone containing rinsing solution had a weight of about 101.5 g. Said rising solution was also analysed by GC analytic and determined to comprise 1.38 weight-% TDA (0,24 weight-% % 2,6-TDA und 1,14 weight-% % 2,4-TDA) corresponding to 1 .4 g TDA.The overall amount of TDA from the filtrate and the rising solution was 19.98 g, minus the initially added TDA of 10.8 g was thus 9.18 g, corresponding to 30 g TDA per 100 g solid (TDI residue + TDI based PU soft foam); Example details and results are summarized in Table 1 below.ResultsDetails of Examples 1, 2 and 3 and the respective results are summarized in Table 1 below:Table 1Overview of methods and yieldsEspecially the comparison of Examples 1 and 2 showed that a relevant yield of TDA could be obtained from a material comprising TDI (TDI residue) at moderate temperatures, wherein the highly corrosive KOHaqcould also be replaced by the much less problematic TDA, not only with a remarkable improvement regarding TDA yield but also allowing use of more inexpensive material for the reaction equipment. Furthermore, it was shown by Example 3 that also mixed materials comprising not only TDI residue but rather TDI residue combined with further components such as TDI based polyurethane (TDI-based PU soft foam) could be used with excellent result in view of TDA recovery yield.Cited LiteratureWO 99 / 54289 A1WO 2004 / 056756 A1DE 25 870847 AEP 1532107 A1EP 0570799 A1EP 0289840 A1EP 02023662 A1EP3556745 A1EP 13736539 A1EP 80102037 A1EP 94107545 A1WO 2006 / 134137 A1GB 2314082ON 2021108991604ON 2022102112203DE 19827086 AON 1003848WO 99 / 65868 A1US 2004 / 0260117 A1EP 2 912 010 B1Prior Art Disclosure; Issue 684; paragraphs

[1000] to

[8005] ; ISSN: 2198-4786; published: February 12, 2024

Claims

Claims1 . Process for recovering toluene diamine (TDA) from a toluene diisocyanate (TD I) comprising material comprising a) providing a TDI comprising material and a material comprising a TDI based polyurethane; b) contacting the materials provided in a) with an alcohol in an aqueous solution, thereby obtaining an aqueous mixture comprising TDA; wherein the TDI comprising material of a) comprises a residue from TDI preparation, and the material comprising a TDI based polyurethane of a) comprises a TDI based polyurethane foam.

2. The process of claim 1 comprising c) separating the TDA from the aqueous mixture comprising TDA obtained in b).

3. The process of claim 1 or 2, wherein the TDI comprising material of a) is a residue from TDI preparation, wherein preferably, the TDI comprising material of a) comprises, preferably is, a residue obtained or obtainable from a process for preparing TDI comprising phosgenation of TDA, more preferably a residue obtained or obtainable from a process for preparing TDI comprising phosgenation of TDA and, preferably subsequent, distillative removal of TDI and / or more preferably a residue obtained or obtainable from a process for preparing TDI comprising phosgenation of TDA, subsequent distillative removal of TDI and subsequent drying.

4. The process of any one of claims 1 to 3, wherein the material comprising a TDI based polyurethane comprises a TDI based polyurethane soft foam.

5. The process of any one of claims 1 to 4, wherein at least 95 weight-% of the material(s) provided in a) consist of TDI comprising material and material comprising a TDI based polyurethane, wherein the total weight of the material (s) provided in a) are 100 weight-%.

6. The process of any one of claims 1 to 5, wherein at last 5 weight-%, preferably at last 10 weight-%, more preferably at least 20 weight-%, more preferably at least 30 weight-%, more preferably at least 40 weight-%, more preferably at least 50 weight-%, more preferably at least 60 weight-%, more preferably at least 70 weight-%, more preferably at least 80 weight-%, more preferably at least 90 weight-%, more preferably at least 95 weight-%, of the material(s) provided in (a) consist of a TDI comprising material, preferably a residue from TDI preparation, more preferably a TDI distillation residue, wherein total weight of the material(s) provided in a) are 100 weight-%.

7. The process of any one of claims 1 to 6, wherein contacting in b) is done in the presence of a basic catalyst,wherein the basic catalyst is preferably selected from the group consisting of organic amine, preferably selected from substituted or unsubstituted pyridine, substituted or unsubstituted imidazole; primary amine; polyamine, preferably diamine, more preferably TDA; ammonia; alkali hydroxide; and mixtures of two or more thereof; wherein the one or more substitutents are selected from hydrogen atom and Ci to C3 alkyl group; or wherein the basic catalyst is selected from the group consisting of alkali hydroxide, TDA and mixtures of alkali hydroxide and TDA, more preferably selected from the group consisting of KOH, TDA and mixtures of KOH and TDA, more preferably the catalyst comprises at least TDA, more preferably the catalyst is TDA.

8. The process of any one of claims 1 to 7, wherein the alcohol of b) is selected from the group consisting of methanol, ethanol, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, methylene glycol, 2-methyl-1 ,3-propanediol and mixtures of two or more thereof, wherein the alcohol of b) preferably comprises at least diethylene glycol, more preferably is diethylene glycol.

9. The process of any one of claims 2 to 8, wherein c) comprises c.1) separation of liquid phase and solid phase of the aqueous mixture comprising TDA obtained in b), preferably by a physical separation method, thereby obtaining a liquid phase comprising TDA; c.2) separating the TDA from the liquid phase obtained in c.1).

10. The process of any one of claims 2 to 9, comprising if the material provided in a) comprises a TDI based polyurethane, d) separating polyol released from the TDI based polyurethane and comprised in the liquid mixture obtained in b) and / or from the liquid phase obtained in c.2).

11. A combined process for preparing TDI and for recovering TDA, the process for preparing TDI comprisingA) introducing a liquid stream comprising at least TDA and a solvent into a reaction zone,B) subjecting the TDA comprised in the liquid stream to isocyanate forming conditions in the reaction zone, comprising introducing a phosgene-containing stream into the reaction zone, thereby forming TDI;C) removing from the reaction zone a liquid mixture comprising TDI;D) optionally separating remaining phosgene, optionally carbon dioxide, and optionally hydrochloride from the liquid mixture and removing the solvent, thereby obtaining a TDI comprising phase;E) separating TDI from the TDI comprising phase, preferably by distillation, obtaining a material, which still comprises TDI but is depleted of TDI compared to the TDI comprising phase (TDI comprising material); the process for recovering TDA comprisingG) contacting the TDI comprising material obtained in E) with an alcohol in an aqueous solution, thereby obtaining an aqueous mixture comprising TDA; the combined process comprisingX) addition of a TDI based polyurethane foam, preferably a TDI based polyurethane soft foam, to the TDI comprising material obtained in E) before F) and contacting in F) the TDI comprising material obtained in E) together with the TDI based polyurethane with the alcohol in an aqueous solution, thereby obtaining an aqueous mixture comprising TDA.

12. TDA obtained or obtainable from a process of any one of claims 1 to 10 or from the combined process of claim 11.

13. Use of the TDA of claim 12 for the preparation of TDI.

14. Method for preparing TDI comprisingI) providing TDA of claim 12;II) preparing TDI from the TDA provided in I), preferably by phosgenation.

15. A process, preferably according to any one of claims 1 to 10 or 11 or 14, comprising the step of converting the TDA obtainable or obtained by the process according to any one of claims 1 to 10 or the TDA obtainable or obtained by the combined process according to claim 11, or the polyol obtainable or obtained by the process according to any one of claims 1 to 10 or the polyol obtainable or obtained by the combined process according to claim 11 or a chemical material obtainable or obtained by the process according to any one of claims 1 to 10 or a chemical material obtainable or obtained by the combined process according to claim 11 or the TDI obtainable or obtained by the method of claim 14 or a chemical material obtainable or obtained by the method according to claim 14 to obtain a product Q, wherein the product Q is selected from: building block or monomer; or polymer, preferably polymer A, polymer composition, preferably polymer composition A, or polymer product, preferably polymer product A; or cleaning polymer, cleaning surfactant, descaling compound, cleaning biocide or composition or formulation thereof; or agrochemical composition, agrochemical formulation auxiliary or agrochemically active ingredient; or active pharmaceutical ingredient or intermediate thereof, pharmaceutical excipient, animal feed additive, human food additive, dietary supplements, aroma chemical or aroma composition; or aqueous polymer dispersion, preferably polyurethane or polyurethane - poly(meth)acrylate hybrid polymer dispersion, emulsion, binder for paper and fiber coatings, UV-curable acrylic polymer for hot melts and coatings polyisocyanates, hyperbranched polyester polyol, polymeric dispersant for inorganic binder compositions, unsaturated polyester polyol or 100% curable composition; or cosmetic surfactant, emollient, wax, cosmetic polymer, UV filter, further cosmetic ingredient or composition or formulation thereof; or polymer B, polymer composition B, coating composition, other functional composition, foil, molded body, coating or coated substrate.

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