Treatment of polyol with basic ion exchange resin for low odor

Abstract

The present invention relates to a process for the purification of a polyol comprising the steps of providing a polyol, and subjecting the polyol to a basic purification procedure comprising contacting the polyol with a basic purification agent to obtain a purified polyol having an lower odor rating according to the automotive norm VDA270 compared to the odor rating according to the automotive norm VDA270 of the polyol, wherein the basic purification agents comprise a basic ion exchanger.

Description

Treatment of polyol with basic ion exchange resin for low odorTECHNICAL FIELDThe present invention relates to a process for the purification of a polyol to obtain a purified polyol having an improved odor. Further, the present invention relates to a purified polyol obtainable and / or obtained by said process. Yet further, the present invention relates to the use of the purified polyol to prepare a polymer having an improved odor, as well as to a method for preparing a polymer from said purified polyol.INTRODUCTIONPolyols, such as polyether and polyester polyols, are oligomeric or polymeric organic compounds that have a wide range of applications in the preparation of polymer-based foams, materials and coatings, in particular of polyurethane-based plastics. These types of polyols may be prepared via an alkoxylation reaction using a double metal cyanide (DMC) catalyst containing cobalt and zinc, or may originate from a recycling process of polyol-containing polymers. However, in particular when recycling polyurethane foams (e.g. mattresses) by depolymerization, aromatic diamines may be present in the polyol fraction. If these exceed established threshold values, the polyol must be classified as a CMR (carcinogenic, mutagenic and reprotoxic) substance, which is highly undesirable. Therefore, efforts are made to reduce the content of aromatic diamines below these limits. A common method for achieving this is the use of strongly acidic ion exchangers, which however may lead to an unpleasant odor of the polyol and the polymer-based products prepared with such polyol.WO 2024 / 094788 A1 relates to a value chain return process for polyurethane and polyisocyanu-rate rigid foams comprising the removal of one or more additives that is not chemically bonded to the polymer chain, and the further depolymerization to isocyanates, amine derivatives and polyols as well as their separation.US 4987271 relates to a method for purifying polyoxyalkylene alcohol synthesized by ring-opening polymerization using a double metal cyanide catalyst, the method comprising treating said alcohol with a treating agent essentially consisting of a pH buffer, contacting said alcohol with an anion exchange resin and an cation exchange resin in a solution, removing the solvent by vacuum filtration, and filtrating the obtained mixture to obtain a purified polyol.US 4355188 relates to a method comprising treating a polyether polyol containing residues of a double metal cyanide catalyst with a treating agent selected from Na, K, NaOH, and KOH to convert the catalyst residues to an ionic species, adding ethylene oxide during treatment with the treating agent to convert the primary hydroxyl groups to secondary hydroxyl groups, and removing the treating agent and the ionic species from said polyol by passing the mixture through an cation exchange resin.WO 2023 / 241926 A1 relates to a process for recovering a polyol substance from a polyurethane material, wherein the process comprises alcoholising the polyurethane material to obtain a polyol substance rich phase, which may then be purified by contacting said phase with an ion exchange material, in particular with an acidic ion exchange material and a basic ion exchange material.DETAILED DESCRIPTIONThus, it was an object of the present invention to develop a purification process for a polyol to improve the odor of said polyol and products, such as polymers, manufactured from said polyol to ensure a sufficient product quality.Surprisingly, it has been found that by treating a polyol with a basic ion exchanger not only reduces the amount of impurities contained in the polyol but also significantly improves the odor of the polyol. Further, it has been found that polymer foams prepared from the polyol purified with the process of the present invention also exhibit a significantly improved odor.Therefore, the present invention relates to a process for the purification of a polyol, comprising (i) providing a polyol;(ii) subjecting the polyol to a basic purification procedure comprising contacting the polyol with a basic purification agent, obtaining a purified polyol;wherein the basic purification agent comprises, preferably consists of, a basic ion exchanger.It is preferred that said process is a process for the purification of a recycled polyol, wherein the polyol provided in (i) more preferably is a recycled polyol, wherein the recycled polyol is more preferably the polyol obtained in step (i.c) according to the embodiments of the present invention.It is preferred that the polyol is selected from the group consisting of polyester polyols, polyether polyols, polyetherester polyols, polycarbonate polyols, polyurea polyols, styrene-acrylonitrile (SAN) polyols, acrylic polyols, and mixtures of two or more thereof, wherein the polyol more preferably is a polyether polyol.It is preferred that providing the polyol in step (i) comprises, more preferably consists of, preparing a polyol, wherein preparing a polyol comprises(i.A) reacting a starter substance and a monomer, obtaining the polyol.In the case where providing the polyol in step (i) comprises preparing a polyol comprising (i.A), it is preferred that reacting in (i.A) comprises a ring-opening reaction, more preferably a ringopening polymerization.Further in the case where providing the polyol in step (i) comprises preparing a polyol comprising (i.A), it is preferred that the starter substance comprises two or more, more preferably from 2 to 8, hydroxyl groups, two or more primary amino groups, or one or more hydroxyl groups in combination with one or more primary amino groups, preferably 3 hydroxyl groups or one hydroxyl group in combination with one primary amino group, more preferably 3 hydroxyl groups. Further in the case where providing the polyol in step (i) comprises preparing a polyol comprising (i.A), it is preferred that the starter substance is selected from the group consisting of water, ethylene glycol, propylene glycol, diethylene glycole, dipropylene glycole, glycerol, 2-ethyl-2-(hydroxymethyl)-propan-1,3-diol, pentaerythritol, glucose, sorbitol, mannitol, sucrose, polyhydric phenols, castor oils, resols, Mannich condensates composed of phenols, of formaldehyde and of dialkanolamines, melamine, monoethanolamine, ethylenediamine, diethylenetriamine, phenylenediamines, 2,3-, 2-4-, 3,4-, and 2,6-tolylenediamine, 4,4’-, 2,4’-, and 2,2’-diaminodiphenyl methane, and mixtures of two or more thereof, wherein the starter substance preferably is selected from the group consisting of glycerol, 2-ethyl-2-(hydroxymethyl)-propan-1,3-diol, monoethanolamine, and mixtures of two or more thereof, wherein the starter substance more preferably is glycerine, diethylenglycole, or mixtures thereof.Further in the case where providing the polyol in step (i) comprises preparing a polyol comprising (i.A), it is preferred that the hydroxyl number of the starter substance is in the range of from 25 to 2500 mg KOH / g, more preferably in the range of from 300 to 2000 mg KOH / g, more preferably in the range of from 700 to 2000 mg KOH / g, more preferably in the range of from 1300 to 2000 mg KOH / g, more preferably in the range of from 1700 to 1900 mg KOH / g.Further in the case where providing the polyol in step (i) comprises preparing a polyol comprising (i.A), it is preferred that the monomer is selected from the group consisting of ethylene oxide, propylene oxide, butylene oxide, styrene oxide, tetrahydrofurane, epichlorohydrin, and mixtures of two or more thereof, wherein the monomer more preferably is propylene oxide.Further in the case where providing the polyol in step (i) comprises preparing a polyol comprising (i.A), it is preferred that reacting in step (i.A) comprises the use of a catalyst.In the case where reacting in step (i.A) comprises the use of a catalyst, it is preferred that the catalyst comprises a metal selected from the group consisting of K, Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Sn, Ru, Rh, Ir, and mixtures of two or more thereof.Further in the case where reacting in step (i.A) comprises the use of a catalyst, it is preferred that the catalyst comprises Co, more preferably Co and Zn, wherein more preferably the catalyst comprises a zinc cyanocobaltate, more preferably Zn3[Co(CN)e]2.Alternatively, it is preferred that providing the polyol in step (i) comprises, more preferably consists of, preparing a polyol, wherein preparing a polyol comprises(i.a) providing a polymer;(i.b) depolymerizing the polymer provided in (i.a), obtaining a depolymerizedmixture comprising a polyol;(i.c) separating the polyol from the depolymerized mixture obtained in (i.b), obtaining the polyol.In the case where providing the polyol in step (i) comprises preparing a polyol comprising (i.a), (i.b) and (i.c), it is preferred that the polymer provided in (i.a) is a polymer mixture.In the case where the polymer provided in (i.a) is a polymer mixture, it is preferred that wherein the polymer mixture comprises two or more polymers.In the case where the polymer mixture comprises two or more polymers, it is preferred that the two or more independently of each other are a polyurethane.Within the meaning of the process of the present invention, the term “polyurethane” preferably includes polyurea and polyisocyanurate, wherein more preferably a polyurethane is obtainable by reacting a composition A with a composition B as described in in paragraphs

[2003] to

[2007] of Reference RF1.In the case where the two or more polymers independently of each other are a polyurethane, it is preferred that at least two of the two or more polymers comprised in the polymer mixture, preferably all of the two or more polymers comprised in the polymer mixture, are of the same polymer type, wherein said at least two polymers of the same polymer type exhibit a difference in their molar mass distribution and / or their constitutional repeating unit.Further in the case where the polymer mixture comprises two or more polymers, it is preferred that the two or more polymers comprised in the polymer mixture are polyurethane flexible and / or rigid foams, more preferably polyurethane flexible foams.In the case where the two or more polymers comprised in the polymer mixture are polyurethane flexible foams, it is preferred that the polyurethane flexible foam is selected from the group consisting of aromatic isocyanate-based polyurethane flexible foams, more preferably from meth-ylenedi(phenylisocyanate)-based polyurethane flexible foams, oligomeric methylenedi(phenyli-socyanate)-based polyurethane flexible foams, polymeric methylenedi(phenylisocyanate)-based polyurethane flexible foams, toluenediisocyanate-based polyurethane flexible foams and mixtures of two or more thereof.Further in the case where the polymer mixture comprises two or more polymers, it is preferred that the two or more polymers comprised in the polymer mixture comprise one or more poly-ether-based polyurethane(s), wherein providing a polymer in (i.a) comprises(i.a.1 ) sorting the polymer mixture, obtaining a fraction comprising, preferably consisting of, 90 wt.-% or more of polyether-based polyurethane(s);(i.a.2) feeding the fraction obtained in (i.a.2) into step (i.b).Further in the case where providing the polyol in step (i) comprises preparing a polyol comprising (i.a), (i.b) and (i.c), it is preferred that depolymerizing in (i.b) is carried out by a method selected from hydrolysis, glycolysis, polyolysis, acidolysis, hydrogenation, aminolysis, and combinations thereof.Further in the case where providing the polyol in step (i) comprises preparing a polyol comprising (i.a), (i.b) and (i.c), it is preferred that depolymerizing in (i.b) is carried out in the presence of a depolymerization catalyst.Further in the case where providing the polyol in step (i) comprises preparing a polyol comprising (i.a), (i.b) and (i.c), it is preferred that the depolymerized mixture obtained in (i.b) further comprises one or more amines, wherein the one or more amines are more preferably selected from the group consisting of primary amines, secondary amines, tertiary amines, quaternary amines, amides, lactames, carbamates, and mixtures of two or more thereof, wherein the one or more amines more preferably are primary and / or secondary amines.Further in the case where providing the polyol in step (i) comprises preparing a polyol comprising (i.a), (i.b) and (i.c), it is preferred that separating in (i.c) comprises one or more separation steps, wherein the separation steps are selected from the group consisting of distillation, chromatography, precipitation, extraction, and phase separation.It is preferred that providing a polyol in (i) comprises(1.1) providing a polyol;(1.2) subjecting the polyol provided in (i.1) to an acidic purification procedure comprising contacting the polyol with an acidic purification agent, obtaining a prepurifiedpolyol;(1.3) feeding the prepurified polyol obtained in (i.2) as the polyol into step (ii);wherein the acidic purification agent comprises, more preferably consists of, an acidic ion exchanger.In the case where providing a polyol in (i) comprises (i.1), (i.2) and (i.3), it is preferred that providing a polyol in (i.1) comprises, more preferably consists of preparing a polyol, wherein preparing a polyol more preferably comprises the step (i.A) or the steps (i.a), (i.b) and (i.c), more preferably the steps (i.a), (i.b) and (i.c).It is preferred that the basic purification procedure in (ii) and / or, preferably and, the acidic purification procedure in (i.2) is performed under an inert gas atmosphere, wherein the inert gas preferably comprises N2 and / or Ar, more preferably N2, wherein the inert gas more preferably is N2 and / or Ar, more preferably N2.Within the meaning of the present invention, the term “inert gas” preferably relates to a gas that does not readily undergo chemical reactions with other chemical substances and therefore does not readily form chemical compounds, wherein more preferably said term relates to a noble gas or a gaseous compound having a strongly negative standard enthalpy of formation.It is preferred that the basic and / or the acidic purification procedures in steps (ii) and (i.2) comprise(A) heating the polyol;(B) adding a solvent and the basic or acidic purification agent to thepolyol;(C) mixing the polyol containing the solvent and the respective purification agent;(D) separating the polyol obtained in (C) from the solvent and / or, more preferably and, the purification agent, obtaining the purified polyol or the prepurified polyol;wherein more preferably step (B) is carried out prior or after step (A), wherein more preferably step (B) is carried out after step (A).In the case where the basic and / or acidic purification procedure in steps (ii) and (i.2) comprise (A), (B), (C) and (D), it is preferred that heating in step (A) is performed under an inert gas atmosphere, wherein the inert gas more preferably comprises N2 and / or Ar, more preferably N2, wherein the inert gas more preferably is N2 and / or Ar, more preferably N2.Further in the case where the basic and / or acidic purification procedure in steps (ii) and (i.2) comprise (A), (B), (C) and (D), it is preferred that the polyol in step (A) is heated to a temperature in the range of from 40 to 300 °C, more preferably in the range of from 50 to 220 °C, more preferably in the range of from 60 to 150 °C, more preferably in the range of from 70 to 100 °C, more preferably in the range of from 75 to 85 °C.Further in the case where the basic and / or acidic purification procedure in steps (ii) and (i.2) comprise (A), (B), (C) and (D), it is preferred that in step (B) an amount of solvent in the range of from 0.1 to 10 wt.-%, more preferably in the range of from 0.5 to 5 wt.-%, more preferably in the range of from 1 to 3 wt.-%, more preferably in the range of from 1.5 to 2.5 wt.-%, based on the total weight of the polyol, is added.Further in the case where the basic and / or acidic purification procedure in steps (ii) and (i.2) comprise (A), (B), (C) and (D), it is preferred that the solvent is selected from the group consisting of water, methanol, ethanol, propanol, acetone, ethyl acetate, acetonitrile, dimethylcarbonate, diethylcarbonate, diethylether, N-methyl-2-pyrrolidone, N,N-dimethylformamide, tetramethylurea, N,N’-dimethylpropylenurea, and mixtures of two or more thereof, wherein the solvent more preferably is water.Further in the case where the basic and / or acidic purification procedure in steps (ii) and (i.2) comprise (A), (B), (C) and (D), it is preferred that in step (B) an amount of the first or second purification agent in the range of from 0.1 to 12 wt.-%, preferably in the range of from 0.5 to 8 wt.-%, more preferably in the range of from 1 to 6 wt.-%, more preferably in the range of from 2 to 4 wt.-%, more preferably in the range of from 2.5 to 3.5 wt.-%, based on the total weight of the polyol, is added.Further in the case where the basic and / or acidic purification procedure in steps (ii) and (i.2) comprise (A), (B), (C) and (D), it is preferred that mixing in step (C) comprises stirring, wherein stirring preferably is carried out for a time period in the range of from 1 min to 24 h, preferably for a time period in the range of from 30 min to 12 h, more preferably for a time period in the range of from 1 h to 6 h, more preferably for a time period in the range of from 1.5 h to 2.5 h.Further in the case where the basic and / or acidic purification procedure in steps (ii) and (i.2) comprise (A), (B), (C) and (D), it is preferred that step (C) is carried out at the same temperature as step (A).Further in the case where the basic and / or acidic purification procedure in steps (ii) and (i.2) comprise (A), (B), (C) and (D), it is preferred that separating the polyol from the solvent in step (D) comprises subjecting the polyol to a pressure in the range of from 10'11to 900 mbar(abs) and a temperature in the range of from 40 to 300 °C.In the case where separating polyol from the solvent in step (D) comprises subjecting the polyol to a pressure and a temperature, it is preferred that the pressure is in the range of from 0 to 100 mbar(abs), more preferably in the range of from 0 to 50 mbar(abs), more preferably in the range of from 0 to 10 mbar(abs).Further in the case where separating polyol from the solvent in step (D) comprises subjecting the polyol to a pressure and a temperature, it is preferred that the temperature is in the range of from 60 to 220 °C, more preferably in the range of from 80 to 150 °C, more preferably in the range of from 100 to 120 °C.Further in the case where separating polyol from the solvent in step (D) comprises subjecting the polyol to a pressure and a temperature, it is preferred that the polyol is subjected to the pressure and the temperature for a time period in the range of from 1 min to 24 h, more preferably for a time period in the range of from 30 min to 12 h, more preferably for a time period in the range of from 1 h to 6 h, more preferably for a time period in the range of from 1.5 h to 2.5 h.Further in the case where the basic and / or acidic purification procedure in steps (ii) and (i.2) comprise (A), (B), (C) and (D), it is preferred that separating the polyol from the purification agent in step (D) comprises a filtration.In the case where separating the polyol from the purification agent in step (D) comprises a filtration, it is preferred that the filtration is performed under an inert gas atmosphere, wherein the inert gas more preferably is N2 and / or Ar, more preferably N2.It is preferred that the basic ion exchanger comprises a matrix and a functional group.In the case where the basic ion exchanger comprises a matrix and a functional group, it is preferred that the matrix is selected from the group consisting of polystyrene, styrene-divinylben-zene-copolymer, polyacrylate, acryl-divinylbenzene-copolymer, and mixtures of two or more thereof, wherein the matrix more preferably is polystyrene or styrene-divinylbenzene-copolymer.Further in the case where the basic ion exchanger comprises a matrix and a functional group, it is preferred that the functional group comprised in the basic ion exchanger is selected from the group consisting of primary amines, secondary amines, tertiary amines, quaternary amines, and mixtures of two or more thereof, wherein the functional group more preferably comprises, more preferably consists of, tertiary amines.It is preferred that the basic ion exchanger is selected from the group of known ion exchange resins consisting of Lewatit® MP62, Lewatit® K 3433, Lewatit® VP OC 1065, Lewatit® S 5228, Lewatit® Monoplus MP68, Lewatit® S 4528, Lewatit® A 8072 Plus, Lewatit® Monoplus MP64, Lewatit® A 365, Lewatit® A 8072 from Lanxess, and mixtures of two or more thereof, wherein more preferably the basic ion exchanger is Lewatit® MP62.In the case where providing a polyol in (i) comprises (i.1), (i.2) and (i.3) it is preferred that the acidic ion exchanger comprises a matrix and a functional group.In the case where the acidic ion exchanger comprises a matrix and a functional group, it is preferred that the matrix is selected from the group consisting of polystyrene, styrene-divinylben-zene-copolymer, polyacrylate, acryl-divinylbenzene-copolymer, and mixtures of two or more thereof, wherein the matrix more preferably is polystyrene or styrene-divinylbenzene-copolymer.Further in the case where the acidic ion exchanger comprises a matrix and a functional group, it is preferred that the functional group comprised in the acidic ion exchanger is selected from the group consisting of sulfonic acid groups, phosphonic acid groups, aminophosphonic acid groups, phosphinic acid groups, carboxylic acid groups, and mixtures of two or more thereof, wherein the functional group more preferably comprises, more preferably consists of, sulfonic acid groups.Further In the case where providing a polyol in (i) comprises (i.1), (i.2) and (i.3) it is preferred that the surface BET of the acidic ion exchanger is in the range of from 10 to 300 m2 / g, more preferably in the range of from 20 to 200 m2 / g, more preferably in the range of from 25 to 100 m2 / g, more preferably in the range of from 30 to 50 m2 / g.Further In the case where providing a polyol in (i) comprises (i.1 ), (i.2) and (i.3) it is preferred that the pore volume of the acidic ion exchanger is in the range of from 0.1 to 3 cm3 / g, more preferably in the range of from 0.2 to 2 cm3 / g, more preferably in the range of from 0.3 to 1.2 cm3 / g, more preferably in the range of from 0.4 to 0.8 cm3 / g.Further In the case where providing a polyol in (i) comprises (i.1), (i.2) and (i.3) it is preferred that the pore diameter of the acidic ion exchanger is in the range of from 10 to 300 nm, morepreferably in the range of from 20 to 200 nm, more preferably in the range of from 30 to 100 nm, more preferably in the range of from 45 to 80 nm.Further In the case where providing a polyol in (i) comprises (i.1), (i.2) and (i.3) it is preferred that the acidic ion exchanger is selected from the group of known ion exchange resins consisting of Lewatit® K 1267, Lewatit® MonoPlus M800 KR I, Lewatit® K 1131 S, Lewatit® S 100 G1, Lewatit® S 2568, Lewatit® K 2629, Lewatit® S 1568, Lewatit® C 249, Lewatit® HD 50, Lewatit® K 2620, Lewatit® K 1161 , Lewatit® K 2431 , Lewatit® K 2420, Lewatit® K 2440, Lewatit® K 1221, Lewatit® K2624, Lewatit® 2649, Lewatit® K 1461 black, Lewatit® UltraPure 1221 MD, Lewatit® MonoPlus SP 112 KR, Lewatit® MonoPlus S 108 H, Lewatit® S 1668, Lewatit® S 2568 H, Lewatit® MonoPlus SP 112, Lewatit® C 267, Lewatit® MonoPlus S 108, Lewatit® S 1567, Lewatit® MonoPlus MP 800 KR, Lewatit® GF 101, Lewatit® S 2328, Lewatit® MonoPlus S 200 H, Lewatit® MDS 200 H, Lewatit® UltraPure 1216 MD, Lewatit® UltraPure 1213 MD, Lewatit® MonoPlus S 200 KR, Lewatit® MonoPlus S 108 KR, Lewatit® MonoPlus S 215 KR, Lewatit® MonoPlus SP 112 H, and mixtures of two or more thereof, wherein more preferably the purification agent is Lewatit® K 2621.It is preferred that the purified polyol has a lower odor rating according to the automotive norm VDA270 as compared to the odor rating according to the automotive norm VDA270 of the polyol provided in (i).It is preferred that the purified polyol has an odor rating of 3.5 or less according to the automotive norm VDA270, preferably of 3.0 or less.It is preferred that the polyol has an odor rating of more than 3.5 according to the automotive norm VDA270, preferably of 4.0 or more.Further In the case where providing a polyol in (i) comprises (i.1), (i.2) and (i.3), it is preferred that the prepurified polyol has an odor rating of more than 3.5 according to the automotive norm VDA270, preferably of 4.0 or more.Further In the case where providing a polyol in (i) comprises (i.1 ), (i.2) and (i.3), it is preferred that the prepurified polyol has a worse odor rating according to the automotive norm VDA270 compared to the polyol provided in (i.1 ), wherein preferably the prepurified polyol has an odor rating of more than 3.5 and the polyol provided in (i.1) has an odor rating of 3.5 or less, wherein more preferably the prepurified polyol has an odor rating of 4.0 or more and the polyol provided in (i.1) has an odor rating of 3.0 or less.It is preferred that the polyol provided in (i) and / or provided in (i.1) comprises an impurity, wherein the impurity comprises, more preferably consists of, one or more of an amine, a volatile organic compound (VOC) and a metal M.In the case where the polyol provided in (i) and / or provided in (i.1) comprises an impurity comprising an amine, it is preferred that the amine is an aromatic amine.In the case where the amine is an aromatic amine, it is preferred that the aromatic amine comprises a sterically hindered secondary aromatic amine, more preferably the reaction products of N-phenyl-benzenamine and 2,4,4-trimethylpentene (Irganox® 5057).Further in the case where the amine is an aromatic amine, it is preferred that the aromatic amine comprises one or more of 4,4’-methylene dianiline, 2,2’-methylene dianiline, 2,4’-meth-ylene dianiline, 2,6-toluene diamine, 2, 4-toluene diamine, and polymeric methylene dianiline. In the case where the polyol provided in (i) and / or provided in (i.1) comprises an impurity comprising a VOC, it is preferred that the VOC is selected from the group consisting of aldehydes, pyrazines, dioxanes, alcohols, benzenes, alkanes, alkenes, and mixtures of two or more thereof.In the case where the VOC is an aldehyde, it is preferred that the aldehyde is selected from the group consisting of formaldehyde, acetaldehyde, propylaldehyde, and mixtures of two or more thereof.In the case where the polyol provided in (i) and / or provided in (i.1) comprises an impurity comprising a metal M, it is preferred that the metal M is selected from the group consisting of Cs, Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Cd, Sn, Bi, Ru, Rh, Ir, Hg, Pb, and mixtures of two or more thereof.Further in the case where the polyol provided in (i) and / or provided in (i.1) comprises an impurity comprising a metal M, it is preferred that the metal M comprised in the impurity of the polyol comprises, more preferably consists of, Co, preferably Co and Zn.Further in the case where the polyol provided in (i) and / or provided in (i.1) comprises an impurity, it is preferred that the impurity comprises an amine, an aldehyde and a metal M.Further in the case where the polyol provided in (i) and / or provided in (i.1) comprises an impurity comprising a metal M, it is preferred that the impurity comprises a metal M, wherein the impurity of the metal M in the polyol is in the range of from 5 to 3000 ppmw, more preferably in the range of from 15 to 1500 ppmw, more preferably in the range of from 25 to 500 ppmw, more preferably in the range of from 30 to 200 ppm, more preferably in the range of from 35 to 100ppmw, more preferably in the range of from 38 to 75 ppmw, wherein the metal content is more preferably determined according to Reference Example 1.Further in the case where the polyol provided in (i) and / or provided in (i.1) comprises an impurity comprising a metal M, it is preferred that the ratio of the impurity of the metal M in the polyol and the impurity of the metal M in the purified polyol is in the range of from 1:0.1 to 1:0.9, preferably in the range of from 1:0.2 to 1:0.8, more preferably in the range of 1:0.5 to 1:0.7, more preferably in the range of from 1:0.55 to 1:0.65.Further in the case where the polyol provided in (i) and / or provided in (i.1) comprises an impurity comprising a metal M, it is preferred that the impurity comprises a metal M, wherein the impurity of the metal M in the purified polyol is 120 ppmw or less, more preferably in the range of from 1 to 120 ppmw, more preferably in the range of from 3 to 80 ppmw, more preferably in the range of from 5 to 50 ppmw, more preferably in the range of from 10 to 37 ppmw, more preferably in the range of from 20 to 35 ppmw, wherein the metal content is more preferably determined according to Reference Example 1.It is preferred that in the case where the content of the impurity is below the detection limit, more preferably below 1 ppmw, the respective value is set to zero.Further in the case where the polyol provided in (i) and / or provided in (i.1) comprises an impurity, it is preferred that the prepurified polyol comprises a reduced content of the impurity as compared to the polyol provided in (i.1), more preferably a reduced content of the amine and / or, more preferably and, the metal M comprised in the impurity.Further in the case where the polyol provided in (i) and / or provided in (i.1) comprises an impurity, it is preferred that the purified polyol comprises a reduced content of impurity as compared to the polyol provided in (i), more preferably a reduced content of the aldehyde and / or, more preferably and, the metal M comprised in the impurity.It is preferred that the polyol provided in (i) has a total carbon emission as determined according to automotive norm VDA277 of 100 pg C / g or more, pmore referably in the range of from 150 to 1500 pg C / g, more preferably in the range of from 400 to 1200 pg C / g, more preferably in the range of from 800 to 1000 pg C / g.It is preferred that the ratio of the total carbon emission as determined according to automotive norm VDA277 of the polyol provided in (i) to that of the purified polyol is in the range of from 1:0.01 to 1:0.5, more preferably in the range of from 1:0.03 to 1:0.2, more preferably in the range of from 1 :0.05 to 1 :0.1.It is preferred that the purified polyol has a total carbon emission as determined according to automotive norm VDA277 of less than 100 pg C / g, more preferably in the range of from 1 to 95 pg C / g, more preferably in the range of from 5 to 85 pg C / g, more preferably in the range of from 20 to 80 pg C / g, more preferably in the range of from 50 to 80 pg C / g.It is preferred that the polyol provided in (i) has a propylaldehyde emission as determined according to automotive norm VDA277 of 10 pg C / g or more, more preferably in the range of from 10 to 50 pg C / g, more preferably in the range of from 15 to 25 pg C / g.It is preferred that the ratio of the propylaldehyde emission as determined according to automotive norm VDA277 of the polyol provided in (i) to that of the purified polyol is in the range of from 1:0.01 to 1:0.5, more preferably in the range of from 1:0.03 to 1:0.2, more preferably in the range of from 1 :0.05 to 1 :0.1.It is preferred that the purified polyol has a propylaldehyde emission as determined according to automotive norm VDA277 of less than 10 pg C / g, more preferably less than 5 pg C / g, more preferably less than 1 pg C / g, more preferably below the detection limit as described in VDA277.It is preferred that the prepurified polyol has an acid number in the range of from 0.01 to 0.2 mg KOH / g, more preferably in the range of from 0.05 to 0.15 mg KOH / g, more preferably in the range of from 0.07 to 0.11 mg KOH / g, wherein the acid number is more preferably determined as described in Reference Example 3.It is preferred that the purified polyol has an acid number in the range of from 0.01 to 0.2 mg KOH / g, more preferably in the range of from 0.02 to 0.10 mg KOH / g, more preferably in the range of from 0.03 to 0.07 mg KOH / g, wherein the acid number is more preferably determined as described in Reference Example 3.It is preferred that the process further comprises(iii) adding a stabilizer to the purified polyol, obtaining a stabilized polyol.In the case where the process further comprises (iii), it is preferred that the stabilizer is an antioxidant which inhibits auto-oxidation of the polyol comprised in the stabilized polyol with atmospheric oxygen.Further in the case where the process further comprises (iii), it is preferred that the stabilizer increases the thermal stability of the polyol comprised in the stabilized polyol.Further in the case where the process further comprises (iii), it is preferred that the stabilizer is selected from a compound of the group consisting of phenols, amines, phosphites, thioesters, and mixtures of two or more thereof, wherein the stabilizer more preferably is a hindered phenol or a secondary aromatic amine, more preferably a secondary aromatic amine.In the case where the stabilizer is a secondary aromatic amine, it is preferred that the stabilizer comprises a compound of the general formula (I)wherein R1and R2are H or C1-C12 alkyl, more preferably H, C4-alkyl or C8-alkyl.Further in the case where the process further comprises (iii), it is preferred that the stabilizer is selected from the group of known stabilizers consisting of C7-C9-alkyl 3-(3,5-di-tert-butyl-4-hy- droxyphenyl)propionate (Irganox® 1135), reaction products of N-phenyl-benzenamine and 2,4,4-trimethylpentene (Irganox® 5057), pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxy- phenyl)propionate) (Irganox® 1010), ethylenebis(oxyethylene) bis[3-(5-tert-butyl-4-hydroxy-m- tolyl)propionate] (Irganox® 245), Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (Irganox® 1076), 2',3-bis[3-[3,5-di-tert-butyl-4-hydroxyphenyl]propionyl]propionohydrazide (Irganox® MD 1024), 4-(1-methyl-1-phenylethyl)-N-[4-(1-methyl-1-phenylethyl)phenyl]aniline (Naugard 445), N-isopropyl-N'-phenyl-p-phenylenediamine (Vulkanox 4010 NA), N-phenylnaph- thalen-1-amine (Vulkanox PAN), N-phenylnaphthalen-2-amine (Vulkanox PBN), and mixtures of two or more thereof, wherein more preferably the stabilizer comprises Irganox® 5057.It is preferred that an additive is added to the purified polyol or the stabilized polyol, wherein the additive is selected from the group consisting of plasticizers, blowing agents, curing agents, flame retardants, nucleating agents, antistatic agents, adhesion promoters, biocides, colorants, lubricants, fillers, rubbers, fibers, and mixtures of two or more thereof.It is preferred that step (ii) is carried out 1 year or less preferably 6 months or less, more preferably 3 month or less, more preferably 1 month or less, more preferably 2 weeks or less, more preferably 1 week or less, more preferably 5 days or less, more preferably 2 days or less, after step (i).It is preferred that step (iii) is carried out 1 year or less preferably 6 months or less, more preferably 3 month or less, more preferably 1 month or less, more preferably 2 weeks or less, more preferably 1 week or less, more preferably 5 days or less, more preferably 2 days or less, after step (ii).Further In the case where providing a polyol in (i) comprises (i.1), (i.2) and (i.3) it is preferred that step (i.2) is carried out 1 year or less, more preferably 6 months or less, more preferably 3 month or less, more preferably 1 month or less, more preferably 2 weeks or less, more preferably 1 week or less, more preferably 5 days or less, more preferably 2 days or less, after step (i.1).It is preferred that the polyol provided in (i) originates from a polymer product and wherein the purified polyol obtained in (ii) or (iii) is further converted to a polymer product.In the case where the purified polyol obtained in (ii) or (iii) is further converted to a polymer product, it is preferred that the polymer product is selected from plastics, foams, fibers, rubbers, coatings, adhesives, sealants, elastomers, and mixtures of two or more thereof.Further in the case where the purified polyol obtained in (ii) or (iii) is further converted to a polymer product, it is preferred that the polymer product is comprised in automotive interiors, bedding, furniture, upholstery, carpet underlay, packaging, and / or textiles.Further, the present invention relates to a purified polyol obtainable and / or obtained by the process according to the embodiments of the present invention.Yet further, the present invention relates to a use of a basic ion exchanger, preferably of a basic ion exchanger and an acidic ion exchanger, more preferably the basic ion exchanger according to any one of embodiments 41 to 44 and the acidic ion exchanger according to the embodiments of the present invention, for improving the odor as determined according to the automotive norm VDA270 and / or, preferably and, reducing impurities, preferably the impurities according to the embodiments of the present invention, of a polyol, preferably by carrying out the process according to the embodiments of the present invention.Yet further, the present invention relates to a use of a purified polyol obtainable and / or obtained from the process according to the embodiments of the present invention to prepare a polymer or a polymer product A, preferably having an improved odor according to the automotive norm VDA270 and / or, more preferably and, reduced impurities, more preferably the impurities according to the embodiments of the present invention.It is preferred that the polymer is selected from the group consisting of polyesters, polycarbonates, polyamides, polyurethanes, polyureas, polyisocyanurate, and mixtures of two or more thereof, wherein the polymer preferably is a polyurethane, more preferably a polyurethane foam.Yet further, the present invention relates to a method for preparing a polymer or a polymer product A, comprising(1) preparing a purified polyol according to the embodiments of the present invention;(2) converting the purified polyol, obtaining a polymer or a polymer product A.It is preferred that the polymer obtained in step (2) is selected from the group consisting of polyesters, polycarbonates, polyamides, polyurethanes, polyureas, polyisocyanurate, and mixtures of two or more thereof, wherein the polymer preferably is a polyurethane, more preferably a polyurethane foam.It is preferred that converting in (2) comprises a polymerization reaction, wherein the polymerization reaction preferably comprises reacting the purified polyol with a diisocyanate, wherein the diisocyanate preferably is methylene diphenyl isocyanate and / or toluene diisocyanate.It is preferred that the polymer obtained in (2) has an odor rating of 3.5 or less according to the automotive norm VDA270, preferably of 3.0 or less.It is preferred that the polymer obtained in (2) has a total carbon emission as determined according to automotive norm VDA277 of less than 100 pg C / g, preferably in the range of from 1 to 95 pg C / g, more preferably in the range of from 5 to 85 pg C / g, more preferably in the range of from 20 to 80 pg C / g, more preferably in the range of from 50 to 80 pg C / g.It is preferred that the polymer obtained in (2) has a propylaldehyde emission as determined according to automotive norm VDA277 of less than 10 pg C / g, preferably less than 5 pg C / g, more preferably below the detection limit.Within the meaning of the present invention, the term “basic” preferably means alkaline.Within the meaning of the present invention, the term “recycled polyol” preferably refers to a polyol that is obtainable or obtained from a process in which a polymer and / or a polymer product is recycled, wherein said process more preferably comprises collection and sorting, chemical depolymerization, purification and fractionation, and reformulation and processing.Within the meaning of the present invention, and according to IIIPAC, the term “constitutional repeating unit” preferably refers to the smallest constitutional unit the repetition of which constitutes a regular macro-molecule, a regular oligomer molecule, a regular block or a regular chain.Within the meaning of the present invention, the term “ppmw” preferably relates to parts-per-mil-lion by weight denoting one part of a unit of mass of a respective component per 1 ,000,000 (106) parts of the same unit of mass of a mixture comprising the respective component.The present invention further relates to a process as described above, preferably the process comprising (i) to (ii) as described above, wherein said process (further) comprises the step of converting the purified polyol obtainable or obtained by the process described herein, or a chemical material obtainable or obtained by the process described herein, to obtain a product Q. Said product Q is preferably selected frombuilding block or monomer; orpolymer, preferably polymer A, polymer composition, preferably polymer composition A, or polymer product, preferably polymer product A; orcleaning polymer, cleaning surfactant, descaling compound, cleaning biocide or composition or formulation thereof; oragrochemical composition, agrochemical formulation auxiliary or agrochemically active ingredient; oractive pharmaceutical ingredient or intermediate thereof, pharmaceutical excipient, animal feed additive, human food additive, dietary supplements, aroma chemical or aroma composition; oraqueous polymer dispersion, preferably polyurethane or polyurethane - poly(meth)acry- late 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; orcosmetic 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.Further regarding said product Q, it is preferred thatthe content of the purified polyol obtainable or obtained by the process described herein in the product Q is 1 weight-% or more, 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 / orthe content of the purified polyol obtainable or obtained by the process described herein in the product Q is 100 weight-% or less, more 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; andwherein the content is preferably 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 referred to in the preceding paragraph 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 referred to in the preceding paragraph.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 / orassembling, preferably foaming, synthesizing, chemical conversion, chemically transforming, polymerizing and / or compounding; and / orforming, preferably foaming, extruding and / or molding; and / orfinishing, 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 “building block”, as used in the context of the product Q herein, comprises compounds, which are in a gaseous or liquid state under standard conditions of 0°C and 0.1 MPa. Building blocks are typically used in chemical industry to form secondary products, which provide a higher structural complexity and / or higher molecular weight than the building block on which the secondary product is based. The building block is preferably selected from the group consisting of hydrogen, carbon monoxide, carbon dioxide, ethylene oxide, ethylene glycols, syngas comprising a mixture of hydrogen and carbon monoxide, alkanes, alkenes, alkynes and aromatic compounds. The alkanes, alkenes, alkynes and aromatic compounds comprise in particular 1 to 12 carbon atoms, respectively.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)acry-lates comprising 1 to 22 carbon atoms are preferred, in particular comprising 1 to 8 carbon at-oms. 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] and

[2010] of Reference RF1.The 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, poly-ether-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, comprisesnon-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 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 / polyvinylpyrrolidone-co-polymer. 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 aroma chemicals 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 composition(s) comprising dispersed polymer(s) and is defined in more detail in the section

[6001] entitled “aqueous polymer dispersion” of Reference RF1. The dispersed polymers) 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 herein, comprises polymer(s) made by free-radical emulsion polymerization. Aqueous polyurethane dispersions) are defined in more detail in the section

[6002] entitled “Polyurethane dispersions” of Reference RF1. UV-curable polyurethane(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 hot melt 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 composition(s) 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 polyol(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 dispersants), as used 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 nonionic, 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 paragraph

[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 Perstonal 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 inparagraph

[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 is not the set of claims determining the extent of protection, but represents a suitably structured part of the description directed to general and preferred aspects of the present invention.1. A process for the purification of a polyol, comprising(i) providing a polyol;(ii) subjecting the polyol to a basic purification procedure comprising contacting the polyol with a basic purification agent, obtaining a purified polyol;wherein the basic purification agent comprises, preferably consists of, a basic ion exchanger.2. The process of embodiment 1 , wherein said process is a process for the purification of a recycled polyol, wherein the polyol provided in (i) preferably is a recycled polyol, wherein the recycled polyol is more preferably the polyol obtained in step (i.c) according to any one of embodiments 13 to 24.3. The process of embodiment 1 or 2, wherein the polyol is selected from the group consisting of polyester polyols, polyether polyols, polyetherester polyols, polycarbonate polyols, polyurea polyols, styrene-acrylonitrile (SAN) polyols, acrylic polyols, and mixtures of two or more thereof, wherein the polyol preferably is a polyether polyol.4. The process of any one of embodiments 1 to 3, wherein providing the polyol in step (i) comprises, preferably consists of, preparing a polyol, wherein preparing a polyol comprises(i.A) reacting a starter substance and a monomer, obtaining the polyol.5. The process of embodiment 4, wherein reacting in (i.A) comprises a ring-opening reaction, preferably a ring-opening polymerization.6. The process of embodiment 4 or 5, wherein the starter substance comprises two or more, preferably from 2 to 8, hydroxyl groups, two or more primary amino groups, or one or more hydroxyl groups in combination with one or more primary amino groups, preferably 3 hydroxyl groups or one hydroxyl group in combination with one primary amino group, more preferably 3 hydroxyl groups.7. The process of any one of embodiment 4 to 6, wherein the starter substance is selected from the group consisting of water, ethylene glycol, propylene glycol, diethylene glycole, dipropylene glycole, glycerol, 2-ethyl-2-(hydroxymethyl)-propan-1,3-diol, pentaerythritol, glucose, sorbitol, mannitol, sucrose, polyhydric phenols, castor oils, resols, Mannich condensates composed of phenols, of formaldehyde and of dialkanolamines, melamine, monoethanolamine, ethylenediamine, diethylenetriamine, phenylenediamines, 2,3-, 2-4-, 3,4- , and 2,6-tolylenediamine, 4,4’-, 2,4’-, and 2,2’-diaminodiphenyl methane, and mixtures of two or more thereof, wherein the starter substance preferably is selected from the group consisting of glycerol, 2-ethyl-2-(hydroxymethyl)-propan-1,3-diol, monoethanolamine, and mixtures of two or more thereof, wherein the starter substance preferably is glycerine, di- ethylenglycole, or mixtures thereof.8. The process of any one of embodiments 4 to 7, wherein the hydroxyl number of the starter substance is in the range of from 25 to 2500 mg KOH / g, preferably in the range of from 300 to 2000 mg KOH / g, more preferably in the range of from 700 to 2000 mg KOH / g, more preferably in the range of from 1300 to 2000 mg KOH / g, more preferably in the range of from 1700 to 1900 mg KOH / g.9. The process of any one of embodiments 4 to 8, wherein the monomer is selected from the group consisting of ethylene oxide, propylene oxide, butylene oxide, styrene oxide, tetra- hydrofurane, epichlorohydrin, and mixtures of two or more thereof, wherein the monomer preferably is propylene oxide.10. The process of any one of embodiments 4 to 9, wherein reacting in step (i.A) comprises the use of a catalyst.11. The process of embodiment 10, wherein the catalyst comprises a metal selected from the group consisting of K, Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Sn, Ru, Rh, Ir, and mixtures of two or more thereof.12. The process of any one of embodiments 10 or 11, wherein the catalyst comprises Co, preferably Co and Zn, wherein more preferably the catalyst comprises a zinc cyanocobaltate, preferably Zn3[Co(CN)e]2.13. The process of any one of embodiments 1 to 3, wherein providing the polyol in step (i) comprises, preferably consists of, preparing a polyol, wherein preparing a polyol comprises(i.a) providing a polymer;(i.b) depolymerizing the polymer provided in (i.a), obtaining a depolymerized mixture comprising a polyol;(i.c) separating the polyol from the depolymerized mixture obtained in (i.b), obtaining the polyol.14. The process of embodiment 13, wherein the polymer provided in (i.a) is a polymer mixture.15. The process of embodiment 14, wherein the polymer mixture comprises two or more polymers.16. The process of embodiment 15, wherein the two or more independently of each other are a polyurethanes.17. The process of embodiment 16, wherein at least two of the two or more polymers comprised in the polymer mixture, preferably all of the two or more polymers comprised in the polymer mixture, are of the same polymer type, wherein said at least two polymers of the same polymer type exhibit a difference in their molar mass distribution and / or their constitutional repeating unit.18. The process of any one of embodiments 15 to 17, wherein the two or more polymers comprised in the polymer mixture are polyurethane flexible and / or rigid foams, preferably polyurethane flexible foams.19. The process of embodiment 18, wherein the polyurethane flexible foam is selected from the group consisting of aromatic isocyanate-based polyurethane flexible foams, preferably from methylenedi(phenylisocyanate)-based polyurethane flexible foams, oligomeric meth-ylenedi(phenylisocyanate)-based polyurethane flexible foams, polymeric methylenedi(phe- nylisocyanate)-based polyurethane flexible foams, toluenediisocyanate-based polyurethane flexible foams and mixtures of two or more thereof.20. The process of any one of embodiments 15 to 19, wherein the two or more polymers comprised in the polymer mixture comprise one or more polyether-based polyurethane(s), wherein providing a polymer in (i.a) comprises(i.a.1 ) sorting the polymer mixture, obtaining a fraction comprising, preferably consisting of, 90 wt.-% or more of polyether-based polyurethane(s);(i.a.2) feeding the fraction obtained in (i.a.2) into step (i.b).21. The process of any one of embodiments 13 to 20, wherein depolymerizing in (i.b) is carried out by a method selected from hydrolysis, glycolysis, polyolysis, acidolysis, hydrogenation, aminolysis, and combinations thereof.22. The process of any one of embodiments 13 to 21 , wherein depolymerizing in (i.b) is carried out in the presence of a depolymerization catalyst.23. The process of any one of embodiments 13 to 22, wherein the depolymerized mixture obtained in (i.b) further comprises one or more amines, wherein the one or more amines are preferably selected from the group consisting of primary amines, secondary amines, tertiary amines, quaternary amines, amides, lactames, carbamates, and mixtures of two or more thereof, wherein the one or more amines more preferably are primary and / or secondary amines.24. The process of any one of embodiments 13 to 23, wherein separating in (i.c) comprises one or more separation steps, wherein the separation steps are selected from the group consisting of distillation, chromatography, precipitation, extraction, and phase separation.25. The process of any one of embodiments 1 to 24, wherein providing a polyol in (i) comprises(1.1) providing a polyol;(1.2) subjecting the polyol provided in (i.1) to an acidic purification procedure comprising contacting the polyol with an acidic purification agent, obtaining a prepurified polyol;(1.3) feeding the prepurified polyol obtained in (i.2) as the polyol into step (ii); wherein the acidic purification agent comprises, preferably consists of, an acidic ion exchanger.26. The process of embodiment 25, wherein providing a polyol in (i.1) comprises, preferably consists of preparing a polyol, wherein preparing a polyol preferably comprises the step (i.A) or the steps (i.a), (i.b) and (i.c), more preferably the steps (i.a), (i.b) and (i.c).27. The process of any one of embodiments 1 to 26, wherein the basic purification procedure in (ii) and / or, preferably and, the acidic purification procedure in (i.2) is performed under an inert gas atmosphere, wherein the inert gas preferably comprises N2 and / or Ar, more preferably N2, wherein the inert gas preferably is N2 and / or Ar, more preferably N2.28. The process of any one of embodiments 1 to 27, wherein the basic and / or the acidic purification procedures in steps (ii) and (i.2) comprise(A) heating the polyol;(B) adding a solvent and the basic or acidic purification agent to thepolyol;(C) mixing the polyol containing the solvent and the respective purification agent;(D) separating the polyol obtained in (C) from the solvent and / or, preferably and, the purification agent, obtaining the purified polyol or the prepurified polyol;wherein preferably step (B) is carried out prior or after step (A), wherein more preferably step (B) is carried out after step (A).29. The process of embodiment 28, wherein heating in step (A) is performed under an inert gas atmosphere, wherein the inert gas preferably comprises N2 and / or Ar, more preferably N2, wherein the inert gas more preferably is N2 and / or Ar, more preferably N2.30. The process of embodiment 28 or 29, wherein the polyol in step (A) is heated to a temperature in the range of from 40 to 300 °C, preferably in the range of from 50 to 220 °C, more preferably in the range of from 60 to 150 °C, more preferably in the range of from 70 to 100 °C, more preferably in the range of from 75 to 85 °C.31. The process of any one of embodiments 28 to 30, wherein in step (B) an amount of solvent in the range of from 0.1 to 10 wt.-%, preferably in the range of from 0.5 to 5 wt.-%, more preferably in the range of from 1 to 3 wt.-%, more preferably in the range of from 1.5 to 2.5 wt.-%, based on the total weight of the polyol, is added.32. The process of any one of embodiments 28 to 31 , wherein the solvent is selected from the group consisting of water, methanol, ethanol, propanol, acetone, ethyl acetate, acetonitrile, dimethylcarbonate, diethylcarbonate, diethylether, N-methyl-2-pyrrolidone, N,N-dime- thylformamide, tetramethylurea, N,N’-dimethylpropylenurea, and mixtures of two or more thereof, wherein the solvent preferably is water.33. The process of any one of embodiments 28 to 32, wherein in step (B) an amount of the first or second purification agent in the range of from 0.1 to 12 wt.-%, preferably in the range of from 0.5 to 8 wt.-%, more preferably in the range of from 1 to 6 wt.-%, more preferably in the range of from 2 to 4 wt.-%, more preferably in the range of from 2.5 to 3.5 wt.-%, based on the total weight of the polyol, is added.34. The process of any one of embodiments 28 to 33, wherein mixing in step (C) comprises stirring, wherein stirring preferably is carried out for a time period in the range of from 1 min to 24 h, preferably for a time period in the range of from 30 min to 12 h, more preferably for a time period in the range of from 1 h to 6 h, more preferably for a time period in the range of from 1.5 h to 2.5 h.35. The process of any one of embodiments 28 to 34, wherein step (C) is carried out at the same temperature as step (A).36. The process of any one of embodiments 28 to 35, wherein separating the polyol from the solvent in step (D) comprises subjecting the polyol to a pressure in the range of from 10'11to 900 mbar(abs) and a temperature in the range of from 40 to 300 °C.37. The process of embodiment 36, wherein the pressure is in the range of from 0 to 100 mbar(abs), preferably in the range of from 0 to 50 mbar(abs), more preferably in the range of from 0 to 10 mbar(abs).38. The process of embodiment 36 or 37, wherein the temperature is in the range of from 60 to 220 °C, preferably in the range of from 80 to 150 °C, more preferably in the range of from 100 to 120 °C.39. The process of any one of embodiments 36 to 38, wherein the polyol is subjected to the pressure and the temperature for a time period in the range of from 1 min to 24 h, preferably for a time period in the range of from 30 min to 12 h, more preferably for a time period in the range of from 1 h to 6 h, more preferably for a time period in the range of from 1.5 h to 2.5 h.40. The process of any one of embodiments 28 to 39, wherein separating the polyol from the purification agent in step (D) comprises a filtration.41. The process of embodiment 40, wherein the filtration is performed under an inert gas atmosphere, wherein the inert gas preferably is N2 and / or Ar, more preferably N2.42. The process of any one of embodiments 1 to 41 , wherein the basic ion exchanger comprises a matrix and a functional group.The process of embodiment 42, wherein the matrix is selected from the group consisting of polystyrene, styrene-divinylbenzene-copolymer, polyacrylate, acryl-divinylbenzene-co-polymer, and mixtures of two or more thereof, wherein the matrix preferably is polystyrene or styrene-divinylbenzene-copolymer.The process of embodiment 42 or 43, wherein the functional group comprised in the basic ion exchanger is selected from the group consisting of primary amines, secondary amines, tertiary amines, quaternary amines, and mixtures of two or more thereof, wherein the functional group preferably comprises, more preferably consists of, tertiary amines. The process of any one of embodiments 1 to 44, wherein the basic ion exchanger is selected from the group of known ion exchange resins consisting of Lewatit® MP62, Lewa-tit® K 3433, Lewatit® VP OC 1065, Lewatit® S 5228, Lewatit® Monoplus MP68, Lewatit® S 4528, Lewatit® A 8072 Plus, Lewatit® Monoplus MP64, Lewatit® A 365, Lewatit® A 8072 from Lanxess, and mixtures of two or more thereof, wherein preferably the basic ion exchanger is Lewatit® MP62.The process of any one of embodiments 25 to 45, wherein the acidic ion exchanger comprises a matrix and a functional group.The process of embodiment 46, wherein the matrix is selected from the group consisting of polystyrene, styrene-divinylbenzene-copolymer, polyacrylate, acryl-divinylbenzene-co-polymer, and mixtures of two or more thereof, wherein the matrix preferably is polystyrene or styrene-divinylbenzene-copolymer.The process of embodiment 46 or 47, wherein the functional group comprised in the acidic ion exchanger is selected from the group consisting of sulfonic acid groups, phosphonic acid groups, aminophosphonic acid groups, phosphinic acid groups, carboxylic acid groups, and mixtures of two or more thereof, wherein the functional group preferably comprises, more preferably consists of, sulfonic acid groups.The process of any one of embodiments 25 to 48, wherein the surface BET of the acidic ion exchanger is in the range of from 10 to 300 m2 / g, preferably in the range of from 20 to 200 m2 / g, more preferably in the range of from 25 to 100 m2 / g, more preferably in the range of from 30 to 50 m2 / g.The process of any one of embodiments 25 to 49, wherein the pore volume of the acidic ion exchanger is in the range of from 0.1 to 3 cm3 / g, preferably in the range of from 0.2 to2 cm3 / g, more preferably in the range of from 0.3 to 1.2 cm3 / g, more preferably in the range of from 0.4 to 0.8 cm3 / g.51. The process of any one of embodiments 25 to 50, wherein the pore diameter of the acidic ion exchanger is in the range of from 10 to 300 nm, preferably in the range of from 20 to 200 nm, more preferably in the range of from 30 to 100 nm, more preferably in the range of from 45 to 80 nm.52. The process of any one of embodiments 25 to 51 , wherein the acidic ion exchanger is selected from the group of known ion exchange resins consisting of Lewatit® K 1267, Lewa- tit® MonoPlus M800 KR I, Lewatit® K 1131 S, Lewatit® S 100 G1, Lewatit® S 2568, Lewatit® K 2629, Lewatit® S 1568, Lewatit® C 249, Lewatit® HD 50, Lewatit® K 2620, Lewatit® K 1161 , Lewatit® K 2431 , Lewatit® K 2420, Lewatit® K 2440, Lewatit® K 1221 , Lewatit® K2624, Lewatit® 2649, Lewatit® K 1461 black, Lewatit® UltraPure 1221 MD, Lewatit® MonoPlus SP 112 KR, Lewatit® MonoPlus S 108 H, Lewatit® S 1668, Lewatit® S 2568 H, Lewatit® MonoPlus SP 112, Lewatit® C 267, Lewatit® MonoPlus S 108, Lewatit® S 1567, Lewatit® MonoPlus MP 800 KR, Lewatit® GF 101, Lewatit® S 2328, Lewatit® MonoPlus S 200 H, Lewatit® MDS 200 H, Lewatit® UltraPure 1216 MD, Lewatit® UltraPure 1213 MD, Lewatit® MonoPlus S 200 KR, Lewatit® MonoPlus S 108 KR, Lewatit® MonoPlus S 215 KR, Lewatit® MonoPlus SP 112 H, and mixtures of two or more thereof, wherein preferably the purification agent is Lewatit® K 2621.53. The process of any one of embodiments 1 to 52, wherein the purified polyol has a lower odor rating according to the automotive norm VDA270 as compared to the odor rating according to the automotive norm VDA270 of the polyol provided in (i).54. The process of any one of embodiments 1 to 53, wherein the purified polyol has an odor rating of 3.5 or less according to the automotive norm VDA270, preferably of 3.0 or less.55. The process of any one of embodiments 1 to 54, wherein the polyol has an odor rating of more than 3.5 according to the automotive norm VDA270, preferably of 4.0 or more.56. The process of any one of embodiments 25 to 55, wherein the prepurified polyol has an odor rating of more than 3.5 according to the automotive norm VDA270, preferably of 4.0 or more.57. The process of any one of embodiments 25 to 56, wherein the prepurified polyol has a worse odor rating according to the automotive norm VDA270 compared to the polyol provided in (i.1), wherein preferably the prepurified polyol has an odor rating of more than 3.5 and the polyol provided in (i.1) has an odor rating of 3.5 or less, wherein more preferablythe prepurified polyol has an odor rating of 4.0 or more and the polyol provided in (i.1) has an odor rating of 3.0 or less.58. The process of any one of embodiments 1 to 57, wherein the polyol provided in (i) and / or provided in (i.1) comprises an impurity, wherein the impurity comprises, preferably consists of, one or more of an amine, a volatile organic compound (VOC) and a metal M.59. The process of embodiment 58, wherein the amine is an aromatic amine.60. The process of embodiment 59, wherein the aromatic amine comprises a sterically hindered secondary aromatic amine, preferably the reaction products of N-phenyl-benzena- mine and 2,4,4-trimethylpentene (Irganox® 5057).61. The process of embodiment 59 or 60, wherein the aromatic amine comprises one or more of 4,4’-methylene dianiline, 2,2’-methylene dianiline, 2,4’-methylene dianiline, 2,6-toluene diamine, 2, 4-toluene diamine, and polymeric methylene dianiline.62. The process of any one of embodiments 59 to 61 , wherein the VOC is selected from the group consisting of aldehydes, pyrazines, dioxanes, alcohols, benzenes, alkanes, alkenes, and mixtures of two or more thereof.63. The process of embodiment 62, wherein the VOC is an aldehyde, wherein the aldehyde is selected from the group consisting of formaldehyde, acetaldehyde, propylaldehyde, and mixtures of two or more thereof.64. The process of any one of embodiments 58 to 63, wherein the metal M is selected from the group consisting of Cs, Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Cd, Sn, Bi, Ru, Rh, Ir, Hg, Pb, and mixtures of two or more thereof.65. The process of any one of embodiments 58 to 64, wherein the metal M comprised in the impurity of the polyol comprises, preferably consists of, Co, preferably Co and Zn.66. The process of any one of embodiments 58 to 65, wherein the impurity comprises an amine, an aldehyde and a metal M.67. The process of any one of embodiments 58 to 66, wherein the impurity comprises a metal M, wherein the impurity of the metal M in the polyol is in the range of from 5 to 3000 ppmw, preferably in the range of from 15 to 1500 ppmw, more preferably in the range of from 25 to 500 ppmw, more preferably in the range of from 30 to 200 ppm, more preferably in the range of from 35 to 100 ppmw, more preferably in the range of from 38 to 75ppmw, wherein the metal content is preferably determined according to Reference Example 1.68. The process of any one of embodiments 58 to 67, wherein the ratio of the impurity of the metal M in the polyol and the impurity of the metal M in the purified polyol is in the range of from 1:0.1 to 1:0.9, preferably in the range of from 1:0.2 to 1:0.8, more preferably in the range of 1:0.5 to 1:0.7, more preferably in the range of from 1:0.55 to 1:0.65.69. The process of any one of embodiments 58 to 68, wherein the impurity comprises a metal M, wherein the impurity of the metal M in the purified polyol is 120 ppmw or less, preferably in the range of from 1 to 120 ppmw, more preferably in the range of from 3 to 80 ppmw, more preferably in the range of from 5 to 50 ppmw, more preferably in the range of from 10 to 37 ppmw, more preferably in the range of from 20 to 35 ppmw, wherein the metal content is preferably determined according to Reference Example 1.70. The process of any one of embodiments 58 to 69, wherein the prepurified polyol comprises a reduced content of the impurity as compared to the polyol provided in (i.1), preferably a reduced content of the amine and / or, preferably and, the metal M comprised in the impurity.71. The process of any one of embodiments 58 to 70, wherein the purified polyol comprises a reduced content of impurity as compared to the polyol provided in (i), preferably a reduced content of the aldehyde and / or, preferably and, the metal M comprised in the impurity.72. The process of any one of embodiments 1 to 71, wherein the polyol provided in (i) has a total carbon emission as determined according to automotive norm VDA277 of 100 pg C / g or more, preferably in the range of from 150 to 1500 pg C / g, more preferably in the range of from 400 to 1200 pg C / g, more preferably in the range of from 800 to 1000 pg C / g.73. The process of any one of embodiments 1 to 72, wherein the ratio of the total carbon emission as determined according to automotive norm VDA277 of the polyol provided in (i) to that of the purified polyol is in the range of from 1 :0.01 to 1 :0.5, preferably in the range of from 1 :0.03 to 1 :0.2, more preferably in the range of from 1 :0.05 to 1:0.1.74. The process of any one of embodiments 1 to 73, wherein the purified polyol has a total carbon emission as determined according to automotive norm VDA277 of less than 100 pg C / g, preferably in the range of from 1 to 95 pg C / g, more preferably in the range of from 5 to 85 pg C / g, more preferably in the range of from 20 to 80 pg C / g, more preferably in the range of from 50 to 80 pg C / g.75. The process of any one of embodiments 1 to 74, wherein the polyol provided in (i) has a propylaldehyde emission as determined according to automotive norm VDA277 of 10 pg C / g or more, preferably in the range of from 10 to 50 pg C / g, more preferably in the range of from 15 to 25 pg C / g.76. The process of any one of embodiments 1 to 75, wherein the ratio of the propylaldehyde emission as determined according to automotive norm VDA277 of the polyol provided in (i) to that of the purified polyol is in the range of from 1 :0.01 to 1 :0.5, preferably in the range of from 1 :0.03 to 1 :0.2, more preferably in the range of from 1 :0.05 to 1 :0.1.77. The process of any one of embodiments 1 to 76, wherein the purified polyol has a propylaldehyde emission as determined according to automotive norm VDA277 of less than 10 pg C / g, preferably less than 5 pg C / g, more preferably less than 1 pg C / g, more preferably below the detection limit as described in VDA277.78. The process of any one of embodiments 25 to 77, wherein the prepurified polyol has an acid number in the range of from 0.01 to 0.2 mg KOH / g, preferably in the range of from 0.05 to 0.15 mg KOH / g, more preferably in the range of from 0.07 to 0.11 mg KOH / g, wherein the acid number is preferably determined as described in Reference Example 3.79. The process of any one of embodiments 1 to 78, wherein the purified polyol has an acid number in the range of from 0.01 to 0.2 mg KOH / g, preferably in the range of from 0.02 to 0.10 mg KOH / g, more preferably in the range of from 0.03 to 0.07 mg KOH / g, wherein the acid number is preferably determined as described in Reference Example 3.80. The process of any one of embodiments 1 to 79, further comprising(iii) adding a stabilizer to the purified polyol, obtaining a stabilized polyol.81. The process of embodiment 80, wherein the stabilizer is an antioxidant which inhibits auto-oxidation of the polyol comprised in the stabilized polyol with atmospheric oxygen.82. The process of embodiment 80 or 81 , wherein the stabilizer increases the thermal stability of the polyol comprised in the stabilized polyol.83. The process of any one of embodiments 80 to 82, wherein the stabilizer is selected from a compound of the group consisting of phenols, amines, phosphites, thioesters, and mixtures of two or more thereof, wherein the stabilizer preferably is a hindered phenol or a secondary aromatic amine, more preferably a secondary aromatic amine.84. The process of embodiment 83, wherein the stabilizer comprises a compound of the general formula (I)wherein R1and R2are H or C1-C12 alkyl, preferably H, C4-alkyl or C8-alkyl.The process of any one of embodiments 80 to 84, wherein the stabilizer is selected from the group of known stabilizers consisting of C7-C9-alkyl 3-(3,5-di-tert-butyl-4-hydroxy- phenyl)propionate (Irganox® 1135), reaction products of N-phenyl-benzenamine and 2,4,4-trimethylpentene (Irganox® 5057), pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hy- droxyphenyl)propionate) (Irganox® 1010), ethylenebis(oxyethylene) bis[3-(5-tert-butyl-4- hydroxy-m-tolyl)propionate] (Irganox® 245), Octadecyl 3-(3,5-di-tert-butyl-4-hydroxy- phenyl)propionate (Irganox® 1076), 2',3-bis[3-[3,5-di-tert-butyl-4-hydroxyphenyl]propio- nyl]propionohydrazide (Irganox® MD 1024), 4-(1-methyl-1-phenylethyl)-N-[4-(1-methyl-1- phenylethyl)phenyl]aniline (Naugard 445), N-isopropyl-N'-phenyl-p-phenylenediamine (Vulkanox 4010 NA), N-phenylnaphthalen-1-amine (Vulkanox PAN), N-phenylnaphthalen- 2-amine (Vulkanox PBN), and mixtures of two or more thereof, wherein preferably the stabilizer comprises Irganox® 5057.The process of any of embodiments 1 to 85, wherein an additive is added to the purified polyol or the stabilized polyol, wherein the additive is selected from the group consisting of plasticizers, blowing agents, curing agents, flame retardants, nucleating agents, antistatic agents, adhesion promoters, biocides, colorants, lubricants, fillers, rubbers, fibers, and mixtures of two or more thereof.The process of any one of embodiments 1 to 86, wherein step (ii) is carried out 1 year or less preferably 6 months or less, more preferably 3 month or less, more preferably 1 month or less, more preferably 2 weeks or less, more preferably 1 week or less, more preferably 5 days or less, more preferably 2 days or less, after step (i).The process of any one of embodiments 1 to 87, wherein step (iii) is carried out 1 year or less preferably 6 months or less, more preferably 3 month or less, more preferably 1 month or less, more preferably 2 weeks or less, more preferably 1 week or less, more preferably 5 days or less, more preferably 2 days or less, after step (ii).The process of any one of embodiments 25 to 88, wherein step (i.2) is carried out 1 year or less, preferably 6 months or less, more preferably 3 month or less, more preferably 1 month or less, more preferably 2 weeks or less, more preferably 1 week or less, more preferably 5 days or less, more preferably 2 days or less, after step (i.1).90. The process of any one of embodiments 1 to 89, wherein the polyol provided in (i) originates from a polymer product and wherein the purified polyol obtained in (ii) or (iii) is further converted to a polymer product.91. The process of embodiment 90, wherein the polymer product is selected from plastics, foams, fibers, rubbers, coatings, adhesives, sealants, elastomers, and mixtures of two or more thereof.92. The process of embodiment 90 or 91 , wherein the polymer product is comprised in automotive interiors, bedding, furniture, upholstery, carpet underlay, packaging, and / or textiles.93. A purified polyol obtainable and / or obtained by the process according to any one of embodiments 1 to 92.94. Use of a basic ion exchanger, preferably of a basic ion exchanger and an acidic ion exchanger, more preferably the basic ion exchanger according to any one of embodiments 42 to 45 and the acidic ion exchanger according to any one of embodiments 46 to 52, for improving the odor as determined according to the automotive norm VDA270 and / or, preferably and, reducing impurities, preferably the impurities according to any one of embodiments 58 to 66, of a polyol, preferably by carrying out the process according to any one of embodiments 1 to 92.95. Use of a purified polyol obtainable and / or obtained from the process according to any one of embodiments 1 to 92 to prepare a polymer or a polymer product A, preferably having an improved odor according to the automotive norm VDA270 and / or, more preferably and, reduced impurities, more preferably the impurities according to any one of embodiments 58 to 66.96. The use of embodiment 95, wherein the polymer is selected from the group consisting of polyesters, polycarbonates, polyamides, polyurethanes, polyureas, polyisocyanurate, and mixtures of two or more thereof, wherein the polymer preferably is a polyurethane, more preferably a polyurethane foam.97. A method for preparing a polymer or a polymer product A, comprising(1) preparing a purified polyol according to any one of embodiments 1 to 92;(2) converting the purified polyol, obtaining a polymer or a polymer product A.98. The method of embodiment 97, wherein the polymer obtained in step (2) is selected from the group consisting of polyesters, polycarbonates, polyamides, polyurethanes, polyureas, polyisocyanurate, and mixtures of two or more thereof, wherein the polymer preferably is a polyurethane, more preferably a polyurethane foam.The method of embodiment 97 or 98, wherein converting in (2) comprises a polymerization reaction, wherein the polymerization reaction preferably comprises reacting the purified polyol with a diisocyanate, wherein the diisocyanate preferably is methylene diphenyl isocyanate and / or toluene diisocyanate.The method of any one of embodiments 97 to 99, wherein the polymer obtained in (2) has an odor rating of 3.5 or less according to the automotive norm VDA270, preferably of 3.0 or less.The method of any one of embodiments 97 to 100, wherein the polymer obtained in (2) has a total carbon emission as determined according to automotive norm VDA277 of less than 100 pg C / g, preferably in the range of from 1 to 95 pg C / g, more preferably in the range of from 5 to 85 pg C / g, more preferably in the range of from 20 to 80 pg C / g, more preferably in the range of from 50 to 80 pg C / g.The method of any one of embodiments 97 to 101, wherein the polymer obtained in (2) has a propylaldehyde emission as determined according to automotive norm VDA277 of less than 10 pg C / g, preferably less than 5 pg C / g, more preferably below the detection limit.A process, preferably according to any of embodiments 1 to 92, comprising the step of converting the purified polyol obtainable or obtained by the process of any of embodiments 1 to 92 to obtain a product Q.The process of embodiment 103, wherein the product Q is selected from:building block or monomer; orpolymer, preferably polymer A, polymer composition, preferably polymer composition A, or polymer product, preferably polymer product A; orcleaning polymer, cleaning surfactant, descaling compound, cleaning biocide or composition or formulation thereof; oragrochemical composition, agrochemical formulation auxiliary or agrochemically active ingredient; oractive pharmaceutical ingredient or intermediate thereof, pharmaceutical excipient, animal feed additive, human food additive, dietary supplements, aroma chemical or aroma composition; oraqueous polymer dispersion, preferably polyurethane or polyurethane -poly(meth)acrylate hybrid polymer dispersion, emulsion, binder for paper and fiber coat-ings, UV-curable acrylic polymer for hot melts and coatings polyisocyanates, hyperbranched polyester polyol, polymeric dispersant for inorganic binder composi-tions, unsaturated polyester polyol or 100% curable composition; orcosmetic 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 substrate105. The process of embodiment 103 or 104,wherein the content of the purified polyol obtainable or obtained by the process of any one of embodiments 1 to 92 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 / orwherein the content of the purified polyol obtainable or obtained by the process of any one of embodiments 1 to 92 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 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 examples and reference examples.EXPERIMENTAL SECTIONReference Example 1 : Determination of metal content via automated acid digestion and ICP-OESAn aliquot of the polyol sample between 400 mg and 450 mg was weighed into quartz glass digestion flasks and loaded into an automated acid digestion system. At the beginning of the digestion, the sample is cracked with sulfuric acid, caesium sulfate and nitric acid in boiling heat and subsequently completely oxidized by the further addition of the aforementioned acids as well as hydrogen peroxide and perchloric acid. Finally, all the acids were eliminated by evaporation to dryness. The resulting residue was dissolved in hydrochloric acid and water by heating tothe boiling point. After completion of the procedure, the digestion flask containing the thus obtained solution was weighed and the exact volume achieved was calculated via density determination.Each sample was prepared in duplicate. A blank sample was prepared in the same manner. The content of the metal was determined via inductively coupled plasma optical emission spectrometry (Agilent 5100 ICP-OES) using external calibrations with matrix matched standards, blank subtraction, and internal standard correction. The reported result was the mean of both duplicates. The detection limit of said method is preferably below 1 ppmw.Reference Example 2: Determination of the OH-numberThe pre-weight sample was dissolved in 10 ml of the acetylation mixture (10 wt% acetic anhydride in N-methyl-2-pyrrolidone) and 30 ml of the catalyst solution (1 wt% 4-pyrrolidino-pyridin in N-methyl-2-pyrrolidone) and reacted for one hour. The mixture was titrated potentiometrically against a KOH solution (0.5 mol / L in methanol).The titration was performed using a Dosimat with a 20 mL exchange unit (Metrohm, Dosimat 794) or an automatic titration unit with 50 mL exchange unit (Metrohm, Titrion 799), a sampler with a sample rack (Metrohm Sampler 815), an electronic evaluation unit (Tiamo Software) and a combined glass electrode.Alternatively, the determination of the OH-number was done according to DIN EN ISO 4629-2, but with 4-pyrrolidino-pyridin instead of DMAP.Reference Example 3: Determination of the acid numberThe pre-weight sample was dissolved in a mixture of iso-propanol / water 1:1. The mixture was titrated potentiometrically against a NaOH solution (0.01 mol / L in methanol). Samples with a higher expected acid number (> 5) are analyzed with KOH solution (0.1 mol / L in methanol).The titration was performed using the equipment as described in Reference Example 2.Alternatively, the determination of the acid number was performed according to DIN EN ISO 4629-2, with minor changes. A mixture of iso-propanol / water 1:1 was used as solvent mixture, instead of toluene / ethanol 2 / 1. Further, NaOH / KOH was dissolved in methanol instead of ethanol.Reference Example 4: Determination of the water content by Karl Fischer titrationAbout 15 ml of anhydrous methanol is added to a titration flask and the Karl Fischer reagent is added to the determined endpoint. The prescribed amount of sample substance is quickly added, stirred for one minute and titrated again with the Karl Fischer reagent to the end point.The titration was performed using the equipment as described in Reference Example 2.Reference Example 5: Preparation of a foam sample from a polyolA foam sample is prepared by manual mixing using a stand mixer or similar device. In the first step, a polyol is mixed with additives (without Kosmos T900LV) and premixed. In a final step, the Kosmos T900LV is added and mixed. Immediately afterwards, the TDI is added and the finished mixture is mixed and poured into an open box. After curing for about 24 hours, the foam sample is cut for analysis.The recipe for the preparation of the foam sample is depicted in Table 1.Table 1. Recipe for the preparation of a foam sample.Example 1: Preparation of a purified polyol according to the present invention2.5 kg of a polyol (Lupranol® 2074) was heated to 80 °C under a nitrogen atmosphere. Then, 2 wt.-% of water and 3 wt.-% of an acidic ion exchanger (Lewatit® K 2621) were added and the resulting mixture was stirred for 2 h. Subsequently, the mixture was placed under vacuum (20-50mbar(abs)) at 110 °C for about 2 h. Finally, the mixture was cooled and then filtered under nitrogen atmosphere to obtain a prepurified polyol.Subsequently, the prepurified polyol was subjected to the same procedure to obtain a purified polyol, wherein however instead of an acidic ion exchanger a basic ion exchanger (Lewatit® MP62) was used.Table 2. Comparison of polyol samplesAs may be taken from Table 2, subjecting the polyol to an acidic ion exchanger reduces the content of the heavy metals cobalt and zinc in the prepurified polyol from 12 ppm to 10 ppm and 27 ppm to 23 ppm, respectively. By subjecting the polyol to the process of the present invention even further reduces the content of the heavy metals cobalt and zinc in the purified polyol from 10 ppm to 8 ppm and 23 ppm to 18 ppm, respectively.Example 2: Odor of polyols according to automotive norm VDA270The VDA270 test serves for the evaluation of the odor characteristics under the influence of temperature and climate. The test is typically performed on materials and components of the motor vehicle trim and on parts in contact with the air introduced into the vehicle interior and is adapted to the measurement of polyol and foam samples.As may be deducted from Table 3, contacting the prepurified polyol with the basic ion exchanger, as according to the present invention, to obtain the purified polyol effectively improves the odor rating from a value of 4.0 to a value of 3.0 as determined with the automotive norm VDA270.Table 3. Odor of Polyols according VDA270Odor rating accordingPolyolVDA270Prepurified polyol (acidic ion exchanger) 4.0Purified polyol (acidic ion exchanger + basic ion ex3.0changer)Example 3: Total carbon emissions in g C / g according to automotive norm VDA277The VDA277 test serves for the evaluation of the total carbon emissions of a non-metallic motor vehicle material. The test is adapted to the measurement of polyol in particular by reducing the sample weight from 2 g to 0.2 g.As may be deducted from Table 4, contacting the prepurified polyol with the basic ion exchanger, as according to the present invention, to obtain the purified polyol effectively reduces the total carbon emissions from 974.0 pg C / g to 78.2 pg C / g as determined with the automotive norm VDA277.Table 4. Total carbon emissions of polyol samples in pg C / g according VDA277Polyol Total carbon emissionsPurified polyol (acidic ion exchanger + basic ion ex78.2 pg C / gchanger)Example 4: Single substance emission in pg C / g according to automotive norm VDA277As may be deducted from Table 5, contacting the prepurified polyol with the basic ion exchanger, as according to the present invention, to obtain the purified polyol effectively reduces the single substance emission of propylaldehyde from 16.5 pg C / g to below the detection limit as determined with the automotive norm VDA277.Table 5. Propylaldehyde emission of polyol samples in pg C / g according VDA277Polyol Propylaldehyde emissionsPurified polyol (acidic ion exchanger + basic ion exBelow detection limitchanger)Example 5: Odor of foams according to automotive norm VDA270-C3The respective foam samples were prepared according to Reference Example 5.As may be deducted from Table 6, a foam sample prepared from the prepurified polyol exhibits a significantly worse odor rating of 5.5 as determined according to VDA270-C3 as compared to a foam sample prepared from the reference polyol having an odor rating of 2.5 according to VDA270-C3. However, a foam sample prepared from 60% of the inventive purified polyol and 40% of the reference polyol exhibits a significantly improved odor rating of 3.0 according to VDA270-C3 as compared to foam sample prepared from the prepurified polyol.Table 6. Odor of Foams according VDA270-C3Odor rating accordingPolyol used for foam preparationVDA270-C360% Purified polyol (acidic ion exchanger + basic3.0ion exchanger) + 40% Reference PolyolExample 6: Aldehyde Emissions of foam samples according to DIN ISO 12219-4:2012-04The respective foam samples were prepared according to Reference Example 5.As may be deducted from Table 7, a foam sample prepared from the prepurified polyol exhibits significantly increased aldehyde emissions, in particular 705 pg / Nm3of propylaldehyde, as compared to a foam sample prepared from the reference polyol having a total aldehyde emission of less than 35 pg / Nm3and <5 pg / Nm3of propylaldehyde. However, a foam sample prepared from 60% of the inventive purified polyol and 40% of the reference polyol exhibits significantly less as compared to foam sample prepared from the prepurified polyol having a total aldehyde emission of less than 46 pg / Nm3and only 5 pg / Nm3of propylaldehyde.Table 7. Aldehyde Emissions of foam samples according DIN ISO 12219-4:2012-04Example 7: Removal efficiency of stabilizersThe macrosorb work-up was performed as follows:To the polyol, 5 wt% deionized water and 5wt% Macrosorb were added, followed by homogenization. The product and the required amount of water were weighed in, then heated to 90 °C over a period of 10 minutes. Afterwards the temperature was increased to 110 °C, and the mixture was maintained under these conditions for 60 minutes to allow the reaction to proceed. The vacuum was subsequently reduced to 10 mbar within 10 minutes. At full vacuum, the reaction mixture was dried for an additional 120 minutes. Finally, the polyol was filtered to remove the solid residues.The preparation of the prepurified polyol was carried out as described in Example 1, starting from a polyol (Lupranol® 2074) containing either 3000 ppmw of a phenolic stabilizer (Irganox® 1076) or 2000 ppmw of a diphenylamine-based stabilizer (Irganox® 5057).The determination of the content of the stabilizer amount was carried out by HPLC-UV.Table 8. Content of the stabilizer in the reference polyol prior to and after work-up via macrosorb or acidic ion exchange.As may be deducted from Table 8, a macrosorb work-up does neither remove a phenolic stabilizer nor a diphenylamine-based stabilizer. In contrast thereto, an acidic ion exchange according to the present invention effectively reduces the content of a diphenylamine-based stabilizer in the polyol.Cited literature- WO 2024 / 094788 A1 - US 4987271- US 4355188- WO 2023 / 241926 A1

Claims

Claims1. A process for the purification of a polyol, comprising(i) providing a polyol;(ii) subjecting the polyol to a basic purification procedure comprising contacting the polyol with a basic purification agent, obtaining a purified polyol having a lower odor rating according to the automotive norm VDA270 as compared to the odor rating according to the automotive norm VDA270 of the polyol provided in (i); wherein the basic purification agent comprises, preferably consists of, a basic ion exchanger.

2. The process claim 1, wherein providing the polyol in step (i) comprises, preferably consists of, preparing a polyol, wherein preparing a polyol comprises(i.a) providing a polymer;(i.b) depolymerizing the polymer provided in (i.a), obtaining a depolymerized mixture comprising a polyol;(i.c) separating the polyol from the depolymerized mixture obtained in (i.b), obtaining the polyol.

3. The process of claim 2, wherein the polymer provided in (i.a) is a polymer mixture comprising two or more polymers, wherein the two or more polymers comprised in the polymer mixture comprise one or more polyether-based polyurethane(s), wherein providing a polymer in (i.a) comprises(i.a.1 ) sorting the polymer mixture, obtaining a fraction comprising, preferably consisting of, 90 wt.-% or more of polyether-based polyurethane(s);(i.a.2) feeding the fraction obtained in (i.a.2) into step (i.b).

4. The process of any one of claims 1 to 3, wherein providing a polyol in (i) comprises (1.1) providing a polyol;(1.2) subjecting the polyol provided in (i.1 ) to an acidic purification procedure comprising contacting the polyol with an acidic purification agent, obtaining a prepurified polyol;(1.3) feeding the prepurified polyol obtained in (i.2) as the polyol into step (ii); wherein the acidic purification agent comprises, preferably consists of, an acidic ion exchanger.

5. The process of claim 4, wherein providing a polyol in (i.1 ) comprises, preferably consists of preparing a polyol.

6. The process of any one of claims 1 to 5, wherein the basic purification procedure in (ii) and / or, preferably and, the acidic purification procedure in (i.2) is performed under an inert gas atmosphere.

7. The process of any one of claims 1 to 6, wherein the basic and / or the acidic purification procedures in steps (ii) and (i.2) comprise(A) heating the polyol;(B) adding a solvent and the basic or acidic purification agent to thepolyol;(C) mixing the polyol containing the solvent and the respective purification agent;(D) separating the polyol obtained in (D) from the solvent and / or the purification agent, obtaining the purified polyol or the prepurified polyol.

8. The process of any one of claims 1 to 7, wherein the purified polyol has an odor rating of 3.5 or less according to the automotive norm VDA270, preferably of 3.0 or less.

9. The process of any one of claims 1 to 8, wherein the polyol provided in (i) and / or provided in (i.1) comprises an impurity, wherein the impurity comprises, preferably consists of, one or more of an amine, a volatile organic compound (VOC) and a metal M.

10. The process of claim 9, wherein the purified polyol comprises a reduced content of impurity as compared to the polyol provided in (i).

11. The process of any one of claims 1 to 10, wherein the ratio of the total carbon emission as determined according to automotive norm VDA277 of the polyol provided in (i) to that of the purified polyol is in the range of from 1:0.01 to 1:0.5.

12. A purified polyol obtainable and / or obtained by the process according to any one of claims 1 to 11.

13. Use of a basic ion exchanger for improving the odor as determined according to the automotive norm VDA270 and / or, preferably and, reducing impurities of a polyol.

14. Use of a purified polyol obtainable and / or obtained from the process according to any one of claims 1 to 11 to prepare a polymer or a polymer product A.

15. A method for preparing a polymer or a polymer product A, comprising(1) preparing a purified polyol according to any one of claims 1 to 11 ;(2) converting the purified polyol, obtaining a polymer or a polymer product A.

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