Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
REACTIVE POLYMERIC RESIN FOR REMOVAL OF ALDEHYDES
Document Type and Number:
WIPO Patent Application WO/2019/097407
Kind Code:
A1
Abstract:
Polymeric primary amine functionalized resins for the removal of aldehydes are disclosed herein. The resins are capable of removing aliphatic and aromatic aldehydes from a variety of feed streams. The resins form covalent imine bonds with aldehyde contaminants. The resulting imine-functional resins can be treated to release the aldehydes and regenerate the primary amine resins for further use.

Inventors:
THARPA KALSANG (IN)
SHARMA DEEPAK (IN)
DESHPANDE RAJ (IN)
KUMAR ARUN (IN)
Application Number:
PCT/IB2018/058936
Publication Date:
May 23, 2019
Filing Date:
November 13, 2018
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
SABIC GLOBAL TECHNOLOGIES BV (NL)
International Classes:
C08G12/46
Foreign References:
EP2552897A12013-02-06
RU2622395C12017-06-15
EP0814076A11997-12-29
US6187973B12001-02-13
CA1330350C1994-06-21
Download PDF:
Claims:
CLAIMS

1. A process for reducing the amount of an aldehyde contaminant from a liquid process stream comprising from greater than 0 to less than 10,000 ppm of at least one aldehyde, said process comprising: contacting the process stream with a crosslinked polymeric resin comprising

primary amine functional groups; allowing the crosslinked polymeric resin primary amine functional groups to

dehydratively couple with the aldehydes in the process stream to give a product stream comprising a treated resin; and separating the treated resin from the product stream; wherein the product stream has a greater than 10% reduction in the amount of

aldehyde compared to the process stream.

2. The process of claim 1, wherein the at least one aldehyde is selected from the group consisting of aliphatic and aromatic aldehydes having from 1 to 12 carbons.

3. The process of any of claims 1 or 2, wherein the resin is coated on an inorganic or polymeric support material selected from the group consisting of beads, films, fibers, pellets, and mesh.

4. The process of any of claims 1 or 2, wherein a color change is associated with the dehydrative coupling of aldehyde to primary amine.

5. The process of any of claims 1 or 2, further comprising processing the treated resin to regenerate the crosslinked polymeric resin comprising primary amine functional groups.

6. The process of any of claims 1 or 2, wherein the liquid process stream comprises a polymer, 2-ethyl hexanol, a glycol, monoethanolamine, diethanolamine, triethanolamine, a polyol, a polyether, acrylonitrile, a phenol, an epoxide, or any combination thereof.

7. The process of any of claims 1 or 2, wherein the resin is Lewait VP OC 1065, Purolite Al 10, or an equivalent resin.

8. A process for reducing the amount of aldehyde in a process stream comprising mono- ethylene glycol, diethylene glycol, triethylene glycol, or any combination thereof, and from greater than 0 to less than 10,000 ppm of at least one aldehyde, said process comprising: contacting the process stream with a crosslinked polymeric resin comprising

primary amine functional groups; allowing the crosslinked polymeric resin primary amine functional groups to

dehydratively couple with aldehydes in the process stream to give a product stream comprising a treated resin; and separating the treated resin from the product stream; wherein the product stream has a greater than 10% reduction in the amount of

aldehyde compared to the process stream.

9. The process of claim 8, wherein the at least one aldehyde is selected from the group consisting of aliphatic and aromatic aldehydes having from 1 to 12 carbons.

10. The process of claim 8 or 9, wherein the resin is based on an aliphatic, aromatic, alicyclic, or heterocyclic allyl amine monomer.

11. The process of either of claims 8 to 9, wherein the resin is Lewait VP OC 1065, Purolite Al 10, or an equivalent resin.

12. The process of either of claims 8 to 9, further comprising processing the treated resin to regenerate the polymeric resin comprising primary amine functional groups.

13. A process for an improvement in product quality of a process stream, measured as a function of transmittance in the UV-Visible region: contacting the process stream with a crosslinked polymeric resin comprising

primary amine functional groups; allowing the crosslinked polymeric resin primary amine functional groups to

dehydratively couple with the aldehydes in the process stream to give a product stream comprising a treated resin; and separating the treated resin from the product stream; wherein the product stream has a greater than 10% improvement in

transmittance in the UV-visible region as compared to the process stream.

14. The process of claim 13, wherein the resin is based on an aliphatic, aromatic, alicyclic, or heterocyclic allyl amine monomer.

15. The process of claim 13 or 14, wherein transmittance is measured at 220 nm, 275 nm, 350 nm, 635 nm, or any wavelength therebetween.

16. The process of either of claims 13 to 14, wherein the resin is coated on an inorganic or polymeric support material selected from the group consisting of beads, films, fibers, pellets, and mesh.

17. The process of either of claims 13 to 14, wherein a color change is associated with the dehydrative coupling of aldehyde to primary amine.

18. The process of claim 17, wherein the color change colorimetrically signals the degree to which imine formation has taken place.

19. The process of either of claims 13 to 14, further comprising processing the treated resin to regenerate the crosslinked polymeric resin comprising primary amine functional groups.

20. The process of either of claims 13 to 14, wherein the liquid process stream comprises water, an environmental sample, an alcoholic beverage, food packaging material, a polymer, 2-ethyl hexanol, a glycol, mono-, di- and triethanolamine, a polyol, a polyether, acrylonitrile, a phenol, an epoxide, or any combination thereof.

Description:
REACTIVE POLYMERIC RESIN FOR REMOVAL OF ALDEHYDES

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority of U.S. Provisional Patent Application No. 62/587,416, filed November 16, 2017, the entire contents of which are hereby incorporated by reference in their entirety.

BACKGROUND OF THE INVENTION

A. Field of the Invention

[0002] The invention generally concerns resinous compositions and methods for employing the resins for the removal of aldehydes from various process streams. B. Description of Related Art

[0003] Aldehydes such as formaldehyde and acetaldehyde are used as building blocks in a number of chemical processes. Formaldehyde is used for the production of various resins and is produced in quantities of over 6,000,000 tons per year. Aldehydes are also by- products from a number of chemical production processes, such as alkylene glycol production. Despite their ubiquity and utility, aldehydes like acetaldehyde and formaldehyde are highly toxic at ppm levels.

[0004] In some instances, aldehydes are unwanted impurities that may affect the quality of a product, or further downstream product or process. In these instances, it is useful to reduce aldehyde content to very low levels, for example, to low ppm levels. The removal of aldehydes has been conventionally performed using ion exchange resins. U.S. 6,187,973 discloses the use of a solid strong acid cation exchange resin for removal of aldehydes. CA1330350C discloses the use of anion exchange resins for the removal of aldehyde impurities from ethylene glycol.

[0005] The use of ion exchange resins for aldehyde removals is associated with a number of drawbacks. Adsorption onto conventional resins relies on relatively weak, non-covalent bonding between the aldehyde and the resin. The polarity of an aldehyde-containing stream may adversely affect favorable aldehyde-resin interactions, thereby hindering absorption. Slow kinetic adsorption onto resin may limit aldehyde removal in streams having low aldehyde concentrations.

SUMMARY OF THE INVENTION

[0006] A discovery has been made that provides a solution to some of the problems discussed above. The solution is premised on the use of a resin containing primary amine functional groups. The resin’s primary amine functional groups can react with aldehydes in a process stream to form imines. The imine-based aldehyde-resin conjugates may then be removed from the product stream with relative ease. The conjugation binding of aldehyde- based contaminants to the resins disclosed herein offers a novel method for removing aldehyde contaminants from a product stream.

[0007] Notably, the conjugation of an aldehyde to a resin primary amine is a reversible reaction. The treated aldehyde-conjugated resins can be subsequently processed to cleave the imine bonds thereby releasing the aldehydes and regenerating the primary amine resins. In some aspects, a resin regeneration protocol may involve treating the imine resins with either oxygen/peroxide under alkaline conditions, washing with a caustic wash, or washing with a solution having a pH of about 4. Regenerated primary amine resins can be re-used as aldehyde removal substrates.

[0008] In a particular aspect of the present invention, a process for reducing the amount of an aldehyde contaminant from a liquid process stream comprising from greater than 0 to less than 10,000 ppm of at least one aldehyde is presented. The process comprises contacting the process stream with a crosslinked polymeric resin comprising primary amine functional groups, allowing the crosslinked polymeric resin primary amine functional groups to dehydratively couple with the aldehydes in the process stream to give a product stream having a reduced concentration of aldehydes and a treated resin. The treated resin may then be separated from the product stream. In some aspects, the product stream has a greater than 10% reduction in the amount of aldehyde compared to the process stream. The reduction in aldehyde content may be determined using gas chromatography (GC).

[0009] Owing to the relatively high reactivity of resin primary amine functional groups, a variety of aldehydes can be removed using the resin. Aliphatic or aromatic aldehydes having 1 to 12 carbon atoms can be reacted with the primary amine resins disclosed herein. In some aspects, the resin may be coated on an inorganic or polymeric support material including but not limited to beads, films, fibers, pellets, and mesh.

[0010] The crosslinked polymeric primary amine resins may be based on an aliphatic, aromatic, alicyclic, or heterocyclic allyl amine monomer. That is, monomers comprising allyl amine functional groups may be polymerized to produce a primary amine resin. In some aspects, an aliphatic, aromatic, alicyclic, or heterocyclic di-allyl crosslinker is used to produce the primary amine resin. In particular aspects, the resin is a crosslinked poly-allyl amine ethylene glycol dimethacrylate resin. In some aspects, the resin is Lewait VP OC 1065, Purolite Al 10, or an equivalent resin. An equivalent resin is a resin that is capable of performing the same function, e.g., conjugation to aldehydes, through the same or related mechanism, e.g., formation of an imine conjugate between resin primary amine and aldehyde. The resins disclosed herein may fashioned or incorporated into various materials including but not limited to films, fibers, solid pellets, and mesh.

[0011] In some embodiments, a crosslinked polymeric primary amine resin changes color upon reaction of the primary amines with aldehyde molecules. The degree to which a color change occurs may act as a quantitative colorimetric indicator of conversion of primary amines to imines. An aldehyde-conjugated imine-functionalized resin may be further reacted to cleave the imine bonds, regenerate primary amine functional groups, and release bound aldehydes. In this way, crosslinked polymeric primary amine resins can be regenerated and subsequently be re-used for aldehyde de-contamination and removal. The crosslinked polymeric primary amine resins are economically attractive, in light of their ability to be continually used and regenerated. A color change may also be observed upon primary amine regeneration.

[0012] The crosslinked polymeric primary amine resins disclosed herein may be used to reduce the concentration of aldehydes in a variety of product streams that include greater than 0 ppm of an aldehyde contaminant. Non-limiting examples of aldehyde-containing product streams include water, environmental samples, alcoholic beverages, food packaging material, polymers, 2-ethyl hexanol, glycols, mono-, di-, or triethanolamine, polyols, polyethers, acrylonitriles, phenols, and epoxides.

[0013] In some embodiments, a process for reducing the amount of aldehyde from a process stream comprising mono-ethylene glycol (MEG), diethylene glycol (DEG), triethylene glycol (TEG), or any combination thereof, and from greater than 0 to less than 10,000 ppm of at least one aldehyde is presented. The process comprises the steps of contacting the process stream with a crosslinked polymeric resin comprising primary amine functional groups, allowing the crosslinked polymeric resin primary amine functional groups to dehydratively couple with aldehydes in the process stream to give a product stream having reduced aldehyde concentration and a treated resin. The treated resin may then be separated from the product stream. The crosslinked polymeric resins may be used to reduce aldehydes in the process stream by greater than 10%.

[0014] In further aspects, a process for preparing a composition comprising mono- ethylene glycol is disclosed. The process comprises the steps of obtaining a process stream comprising mono-ethylene glycol and from greater than 0 to less than 10,000 ppm of at least one aldehyde, contacting the process stream with a crosslinked polymeric resin comprising primary amine functional groups to yield a product stream, and separating the product stream from the treated resin. The process results in the production of a product stream having a reduced amount of aldehyde as compared to the process stream. In some aspects, the composition comprises greater than 50% mono-ethylene glycol.

[0015] In some aspects, a process for the improvement in product quality of a process stream is disclosed. In some aspects, a process for the improvement in product quality of a process stream involves interaction of the product stream with a solid material containing primary amine functional groups, allowing the crosslinked polymeric resin primary amine functional groups to dehydratively couple with the aldehydes in the process stream to give a product stream comprising a treated resin. The treated resin may then be separated from the product stream. The improvement in product quality may be measured as a function of transmittance or absorbance in the UV-visible region. In some aspects, the product stream has a greater than 10% change in transmittance or absorbance as compared to the process stream. In some embodiments, the transmittance is measured at a wavelength of from 200 to 800 nm. In specific embodiments, the transmittance or absorbance may be measured at 220, 275, 350, 635 nm, or any wavelength therebetween. The product may be, but is not limited to, an aldehyde-containing product stream, water, environmental samples, alcoholic beverages, food packaging material, polymers, 2-ethyl hexanol, glycols, mono-, di-, and triethanolamine, polyols, polyethers, acrylonitriles, phenols, epoxides, and mixtures thereof. In some aspects, the product stream is a mixture of glycols along with a solvent such that the solvent comprises less than or equal to 50% of the mass of the product stream. In some aspects, the product stream comprises amino alcohols and their mixtures. In further aspects, the product stream comprises terephthalic acid. In additional aspects, the product stream comprises linear and branched alcohols having a carbon number greater than or equal to 4. In some embodiments, the solid material is an organic polymer with free amine groups. In some aspects, the polymeric material contains predominantly free amino groups along with quaternized amine groups. In some aspects, the free amine constitutes at least 50% of total free and quaternized amine content in the solid.

[0016] The following includes definitions of various terms and phrases used throughout this specification. The terms“about” or“approximately” are defined as being close to as understood by one of ordinary skill in the art. In one non-limiting embodiment, the terms are defined to be within 10%, preferably within 5%, more preferably within 1%, and most preferably within 0.5%.

[0017] The terms“wt.%”,“vol.%”, or“mol.%” refers to a weight, volume, or molar percentage of a component, respectively, based on the total weight, the total volume, or total moles of a material, that includes the component. In a non-limiting example, 10 grams of component in 100 grams of the material is 10 wt.% of component. The term“substantially” and its variations are defined to include ranges within 10%, within 5%, within 1%, or within 0.5%. The terms“inhibiting” or“reducing” or“preventing” or“avoiding” or any variation of these terms, when used in the claims and/or the specification includes any measurable decrease or complete inhibition to achieve a desired result. The term“effective,” as that term is used in the specification and/or claims, means adequate to accomplish a desired, expected, or intended result. The use of the words“a” or“an” when used in conjunction with any of the terms “comprising,” “including,” “containing,” or “having” in the claims, or the specification, may mean“one,” but it is also consistent with the meaning of“one or more,” “at least one,” and“one or more than one.”

[0018] The words“comprising” (and any form of comprising, such as“comprise” and “comprises”),“having” (and any form of having, such as“have” and“has”),“including” (and any form of including, such as“includes” and“include”) or“containing” (and any form of containing, such as“contains” and“contain”) are inclusive or open-ended and do not exclude additional, unrecited elements or method steps. [0019] The methods of the present invention can“comprise,”“consist essentially of,” or “consist of’ particular ingredients, components, compositions, etc. disclosed throughout the specification. With respect to the transitional phase“consisting essentially of,” in one non limiting aspect, a basic and novel characteristic of the methods of the present invention are their abilities to bind to and remove aldehydes from product streams.

[0020] In the context of the present invention, twenty embodiments are now described. Embodiment l is a process for reducing the amount of an aldehyde contaminant from a liquid process stream comprising from greater than 0 to less than 10,000 ppm of at least one aldehyde. The process includes the steps of contacting the process stream with a crosslinked polymeric resin having primary amine functional groups; allowing the crosslinked polymeric resin primary amine functional groups to dehydratively couple with the aldehydes in the process stream to give a product stream containing a treated resin; and separating the treated resin from the product stream; wherein the product stream has a greater than 10% reduction in the amount of aldehyde compared to the process stream. Embodiment 2 is the process of embodiment 1, wherein the at least one aldehyde is selected from the group consisting of aliphatic and aromatic aldehydes having from 1 to 12 carbons. Embodiment 3 is the process of embodiment 1 or 2, wherein the resin is coated on an inorganic or polymeric support material selected from the group consisting of beads, films, fibers, pellets, and mesh. Embodiment 4 is the process of either of embodiments 1 to 3, wherein a color change is associated with the dehydrative coupling of aldehyde to primary amine. Embodiment 5 is the process of either of embodiments 1 to 4, further including the step of processing the treated resin to regenerate the crosslinked polymeric resin having primary amine functional groups. Embodiment 6 is the process of either of embodiments 1 to 5, wherein the liquid process stream contains a polymer, 2-ethyl hexanol, a glycol, monoethanolamine, diethanolamine, triethanolamine, a polyol, a polyether, acrylonitrile, a phenol, an epoxide, or any combination thereof. Embodiment 7 is the process of any of embodiments 1 to 6, wherein the resin is Lewait VP OC 1065, Purolite Al 10, or an equivalent resin.

[0021] Embodiment 8 is a process for reducing the amount of aldehyde in a process stream comprising mono-ethylene glycol, diethylene glycol, triethylene glycol, or any combination thereof, and from greater than 0 to less than 10,000 ppm of at least one aldehyde. The process includes the steps of contacting the process stream with a crosslinked polymeric resin having primary amine functional groups; allowing the crosslinked polymeric resin primary amine functional groups to dehydratively couple with aldehydes in the process stream to give a product stream containing a treated resin; and separating the treated resin from the product stream; wherein the product stream has a greater than 10% reduction in the amount of aldehyde compared to the process stream. Embodiment 9 is the process of embodiment 8, wherein the at least one aldehyde is selected from the group consisting of aliphatic and aromatic aldehydes having from 1 to 12 carbons. Embodiment 10 he process of embodiment 8 or 9, wherein the resin is based on an aliphatic, aromatic, alicyclic, or heterocyclic allyl amine monomer. Embodiment 11 is the process of either of embodiments 8 to 10, wherein the resin is Lewait VP OC 1065, Purolite A110, or an equivalent resin. Embodiment 12 is the process of either of embodiments 8 to 11, further including the step of processing the treated resin to regenerate the polymeric resin having primary amine functional groups.

[0022] Embodiment 13 is a process for an improvement in product quality of a process stream, measured as a function of transmittance in the ETV-Visible region. The process includes the steps of contacting the process stream with a crosslinked polymeric resin having primary amine functional groups; allowing the crosslinked polymeric resin primary amine functional groups to dehydratively couple with the aldehydes in the process stream to give a product stream containing a treated resin; and separating the treated resin from the product stream; wherein the product stream has a greater than 10% improvement in transmittance in the ETV-visible region as compared to the process stream. Embodiment 14 the process of embodiment 13, wherein the resin is based on an aliphatic, aromatic, alicyclic, or heterocyclic allyl amine monomer. Embodiment 15 is the process of embodiment 13 or 14, wherein transmittance is measured at 220 nm, 275 nm, 350 nm, 635 nm, or any wavelength therebetween. Embodiment 16 is the process of either of embodiments 13 to 15, wherein the resin is coated on an inorganic or polymeric support material selected from the group consisting of beads, films, fibers, pellets, and mesh. Embodiment 17 is the process of either of embodiments 13 to 16, wherein a color change is associated with the dehydrative coupling of aldehyde to primary amine. Embodiment 18 is the process of embodiment 17, wherein the color change colorimetrically signals the degree to which imine formation has taken place. Embodiment 19 is the process of either of embodiments 13 to 18, further including the step of processing the treated resin to regenerate the crosslinked polymeric resin having primary amine functional groups. Embodiment 20 is the process of either of embodiments 13 to 19, wherein the liquid process stream contains water, an environmental sample, an alcoholic beverage, food packaging material, a polymer, 2-ethyl hexanol, a glycol, mono-, di- and triethanolamine, a polyol, a polyether, acrylonitrile, a phenol, an epoxide, or any combination thereof.

[0023] Other objects, features and advantages of the present invention will become apparent from the following figures, detailed description, and examples. It should be understood, however, that the figures, detailed description, and examples, while indicating specific embodiments of the invention, are given by way of illustration only and are not meant to be limiting. Additionally, it is contemplated that changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. In further embodiments, features from specific embodiments may be combined with features from other embodiments. For example, features from one embodiment may be combined with features from any of the other embodiments. In further embodiments, additional features may be added to the specific embodiments described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] FIG. 1 depicts the reaction between an aldehyde, RCHO, and a resin having terminal primary amine functional groups. The aldehyde covalently binds to a resin primary amine functional group to give a resin having cleavable imine functional group.

[0025] FIG. 2 depicts the colorimetric change associated with resin deactivation. The deactivated resin in the upper region has a yellow tint as compared to the active resin in the lower region.

[0026] FIG. 3 is an illustration of a column into which reactive polymeric resin has been loaded. An aldehyde-containing sample may be fed into the inlet at the top of the column, through the reactive polymeric resin, and out the sample outlet with a reduced aldehyde concentration.

[0027] FIG. 4 is a GC chromatogram showing the reduction in both formaldehyde and acetaldehyde from a diethylene glycol sample.

[0028] FIG. 5 is a graph depicting acetaldehyde removal from MEG, DEG, and TEG samples having low initial acetaldehyde concentrations. [0029] FIG. 6 is a GC chromatogram showing the reduction of 2-ethyl hexanal in a 2- ethyl hexanol sample.

DETAILED DESCRIPTION OF THE INVENTION

[0030] The commonly-employed resins for removal of aldehydes include atributes that contribute to poor aldehyde-removal performance. Adsorption onto conventional resins relies on non-covalent bonding between the aldehyde and the resin. Non-covalent bonding is a relatively weak interaction in comparison to the covalent aldehyde conjugation activity of the resins disclosed herein. The polarity of an aldehyde-containing stream may obstruct favorable aldehyde-resin interactions and adversely affect the absorption of the aldehyde onto the resin. Therefore, adsorption of aldehydes onto conventional resins depends upon the stream medium matrix, and high or mildly alkali matrix streams result in poor aldehyde absorption. Finally, slow kinetic adsorption onto the resin limits aldehyde removal in streams having low aldehyde concentrations.

[0031] The presently claimed crosslinked polymeric primary amine resins circumvent many of the problems associated with commonly-employed resins by employing a covalent aldehyde-conjugation mechanism. This results in resins having features that are not realized by commonly-employed resins. The reaction between aldehyde and the primary amine on the resin surface is rapid, therefore, removal of aldehydes is nearly instantaneous. Because one aldehyde molecule reacts with one primary amine functional group, only a stoichiometric amount of resin primary amine is consumed by aldehydes (FIG. 1). The removal of aldehydes on the proposed resins is less dependent on the sample matrix, thereby allowing resins to be used in diverse matrix conditions. The presently disclosed resins can be regenerated after reacting with aldehydes. Regeneration may be accomplished by treatment with either oxygen/peroxide under alkaline conditions, with a caustic wash, or washing with a solution having a pH of about 4. Aldehyde conjugation onto the present resins may be associated with a color change that allows for colorimetric determination of aldehyde- conjugation and release (FIG. 2). The presently claimed resins may be coated on a support and/or may be incorporated into a variety of materials including, but not limited to films, fibers, pellets, and mesh. EXAMPLES

[0032] The present invention will be described in greater detail by way of specific examples. The following examples are offered for illustrative purposes only, and are not intended to limit the invention in any manner. Those of skill in the art will readily recognize a variety of noncritical parameters which can be changed or modified to yield essentially the same results.

Example 1: General Synthetic Route for Preparation of Resin

[0033] A primary amine monomer may be polymerized, optionally in the presence of a crosslinker to produce a resin having the general formula depicted below. The monomer may be an aliphatic, aromatic, alicyclic, or a heterocyclic monomer. The crosslinker may be an aliphatic, aromatic, alicyclic, or a heterocyclic crosslinker. Reaction between monomer and crosslinker may initiated using a radical initiator. A porogen may be optionally included to generate a porous resin construction.

Example 2: Synthesis of an Exemplary Resin [0034] Allyl amine and ethylene glycol dimethacrylate crosslinker were reacted under nitrogen by a thermal radical polymerization. The resulting AA-Co-EGDMA monolith was ground and unreacted monomers and catalyst were washed to give the representative AA-Co- EGDMA resin structure depicted below.

Example 3: Aldehyde Removal Using AA-Co-EGDMA [0035] AA-Co-EGDMA resin described above was loaded in a vertical column as depicted in FIG. 3, and aldehyde was passed through the resin.

[0036] Preliminary experiments indicated a reduction in stream aldehyde concentration. DEG containing aldehydes (formaldehyde 200 ppm and acetaldehyde 700 ppm) was passed through the column loaded with the resin described above with a flow rate of 3 beds volume per hour on 4 mL of resin (12 ml/hour). Treated samples were collected at the outlet of the column where the acetaldehyde concentration was reduced from 700 ppm to 12 ppm, and formaldehyde was reduced from 200 ppm to 30 ppm (FIG. 4). Example 4: Acetaldehyde Removal From MEG, DEG, and TEG

[0037] MEG, DEG, and TEG were spiked with low initial acetaldehyde concentrations in order to assess aldehyde removal at low concentrations (20 to 55 ppm). As depicted in FIG. 5, acetaldehyde removal was 94% in MEG, 88% in DEG, and 95% in TEG. [0038] The Examples demonstrate the effectiveness of the presently claimed resins at removing aldehydes, both aliphatic and aromatic, from a variety of streams. The resins were successful at removing aldehyde combinations (formaldehyde + acetaldehyde) and removed -90% of aldehydes present in samples having low initial aldehyde concentrations.

Example 5: Removal of Aromatic Aldehyde from Terephthalic Acid [0039] A solution of crude terephthalic acid in dichloromethane containing 1.66% of 4- carboxy benzaldehyde (4-CBA) was passed through the resin above. The resulting terephthalic acid contained 0.29% of 4-CBA, a reduction of 82%.

Example 6: Removal of 2-Ethyl Hexanal From 2-Ethyl Hexanol

[0040] 2-Ethyl hexanol containing 337 ppm of 2-ethyl hexanal (aldehyde) was passed once through the resin described above. The resulting 2-ethyl hexanol contained 148 ppm of 2-ethyl hexanal, a reduction of 44%. The product purity improved from 98.886% to 98.897%.