Methods of recovering catalysts from byproduct streams

Abstract

Methods of recovering one or more materials of interest from a byproduct stream, such as a byproduct stream of a process for producing a polymerizable monomer or precursor thereof, such as an acrylate or methacrylate monomer. The one or more materials of interest may include a catalyst, such as a transesterification catalyst, a polymerization inhibitor, etc. The methods may include subjecting a byproduct stream to a distillation at a temperature and a vacuum pressure effective to separate from the byproduct stream at least a portion of one or more volatile compounds, thereby forming a distillation residue, and contacting the distillation residue and an amount of a liquid effective to form a precipitate that includes one or more materials of interest.

Description

FI2353 PCT Attorney Docket No.92230-0372 METHODS OF RECOVERING CATALYSTS FROM BYPRODUCT STREAMS Cross-reference to Related Applications

[0001] This application claims priority to Finnish Patent Application No.20245990, filed August 8, 2024, and U.S. Provisional Patent Application No.63 / 655,625, filed June 4, 2024, which are incorporated by reference herein. Technical Field

[0002] The present disclosure generally relates to methods of recovering one or more materials, such as catalysts, from byproduct streams. Background

[0003] Byproduct streams from a number of manufacturing processes contain one or more valuable materials, such as catalysts, that are commonly discarded or destroyed by incineration or otherwise.

[0004] For example, byproduct streams from processes for producing (meth)acrylate monomers, such as processes for producing dimethylaminoethyl acrylate (ADAME), can include catalysts, polymerization inhibitors, etc. Attempts have been made to recover one or more materials from byproduct streams of ADAME-producing processes. The byproduct streams, for example, have been subjected to batch distillation, but this technique typically produces large amounts of high viscosity tar. The high viscosity tar is difficult to process, and typically includes a number of unknown compounds.

[0005] Attempts to recover catalysts, such as dibutyl tin oxide (DBTO), commonly lead to catalyst deactivation (see, e.g., U.S. Patent Application Publication No.2021 / 0114969). DBTO can be an advantageous catalyst because it is very active at relatively low dosages, and can be recycled multiple times. Nevertheless, DBTO typically is deactivated upon recycling, which makes it necessary to replace it regularly, which can be costly and inconvenient.

[0006] There remains a need for improved methods for recovering one or more valuable materials from byproduct streams. Brief Summary

[0007] Provided herein are methods of recovering one or more materials of interest, such as catalysts and polymerization inhibitors, from a byproduct stream. In someFI2353 PCT Attorney Docket No.92230-0372 embodiments, the recovered catalysts retain their activity, or their activity is not diminished to an undesirable extent.

[0008] In some embodiments, the methods include providing a byproduct stream; subjecting the byproduct stream to a distillation at a temperature and a vacuum pressure effective to separate from the byproduct stream at least a portion of one or more volatile compounds, thereby forming a distillation residue; and contacting the distillation residue and an amount of a liquid effective to form a precipitate, wherein the precipitate includes at least one material of interest. The at least one material of interest may include a catalyst, such as a transesterification catalyst, a polymerization inhibitor, or a combination thereof. The catalyst, for example, may include DBTO.

[0009] Additional aspects will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the aspects described herein. The advantages described herein may be realized and attained by means of the elements and combinations particularly pointed out in the listing of embodiments and the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive. Detailed Description

[0010] Provided herein are methods of recovering one or more materials of interest from a byproduct stream. In some embodiments, the methods include providing a byproduct stream.

[0011] Byproduct Stream

[0012] The byproduct stream generally may be from any chemical process. In some embodiments, the byproduct stream is from a process that produces a polymerizable monomer or a precursor thereof, such as an acrylate monomer or a methacrylate monomer.

[0013] As an example, the byproduct stream may be from a process for producing dimethylaminoethyl acrylate (ADAME). The byproduct stream may include methyl 3-(2- (dimethylamino)ethoxy)propanoate, ethyl 3-(2-(dimethylamino)ethoxy)propanoate, 2- (dimethylamino)ethyl 3-methoxypropanoate, 2-(dimethylamino)ethyl 3-ethoxypropanoate, 2- (dimethylamino)ethyl 3-(2-(dimethylamino)ethoxy)propanoate, 2-(dimethylamino)ethyl acrylate, 2-(dimethylamino)ethan-1-ol, methyl 3-methoxypropanoate, ethyl 3- ethoxypropanoate, or a combination thereof:FI2353 PCT Attorney Docket No.92230-0372.producing dimethylaminoethyl methacrylate. 2-ethoxy]- 1-ol, or aFI2353 PCT Attorney Docket No.92230-0372 a

[0016] In some embodiments, the distillation is performed at a temperature and a vacuum pressure effective to separate from the byproduct stream at least a portion of one or more volatile compounds, thereby forming a distillation residue.

[0017] Temperature

[0018] The temperature at which a distillation is performed may be selected to (i) avoid or minimize the formation of components, such as relatively high molecular weight components, that are difficult to separate from a material of interest, (ii) promote the removal of one or more volatile components, (iii) prevent or minimize the risk of negatively impacting a material of interest, such as the activity of a catalyst, or (iv) a combination thereof.

[0019] In some embodiments, the temperature is about 100 °C or less, about 95 °C or less, about 90 °C or less, about 85 °C or less, about 80 °C or less, about 75 °C or less, about 70 °C or less, about 65 °C or less, or about 60 °C or less. In some embodiments, the temperature is about 30 °C to about 100 °C, about 30 °C to about 95 °C, about 30 °C to about 90 °C, about 30 °C to about 85 °C, about 30 °C to about 80 °C, about 30 °C to about 75 °C, about 30 °C to about 70 °C, about 30 °C to about 65 °C, about 30 °C to about 60 °C, about 30 °C to about 55 °C, about 30 °C to about 50 °C.

[0020] Vacuum Pressure

[0021] The vacuum pressure at which a distillation is performed may be selected to increase the likelihood that one or more volatile components are separable via the distillation.FI2353 PCT Attorney Docket No.92230-0372

[0022] In some embodiments, the vacuum pressure is about 10 millibars or less, about 8 millibars or less, about 6 millibars or less, about 4 millibars or less, about 2 millibars or less, about 1 millibar or less, about 0.5 millibars or less, or about 0.1 millibars or less.

[0023] Precipitation

[0024] In some embodiments, the methods include contacting a distillation residue and an amount of a liquid effective to form a precipitate, wherein the precipitate includes at least one material of interest. The amount of the liquid may be a minimum amount needed to form a precipitate. The precipitate typically is in the form of particles, which may be separated from the amount of a liquid using any known technique, e.g., filtration, etc.

[0025] The liquid added to form a precipitate may include water, an organic liquid, or a combination thereof. The organic liquid may be miscible with water. The organic liquid may include an alcohol, such as an alcohol of formula ROH, wherein R is a C1-C6hydrocarbyl. In some embodiments, the organic liquid includes methanol, ethanol, propanol (e.g., n-propanol, isopropanol, or a combination thereof), butanol (e.g., n-butanol, isobutanol, tert-butanol, sec-butanol, or a combination thereof), or a combination thereof. The organic liquid, such as methanol, may be produced by a trans-esterification reaction, as described herein, thereby further reducing the environmental impact of some embodiments of the methods described herein.

[0026] The liquid generally may be at any pH. In some embodiments, the pH of the liquid is 7 or less, less than 7, or about 5 to about 7.

[0027] A distillation residue generally may be at any temperature when contacted with an amount of liquid. In some embodiments, a distillation residue is at an elevated temperature when contacted with an amount of liquid, such as an elevated temperature at or below the temperature at which the distillation was performed. For example, a distillation residue may be contacted with an amount of liquid after the distillation and before the distillation residue has cooled to ambient temperature.

[0028] The contacting of a distillation residue and an amount of liquid may include applying one or more forces, e.g., mixing forces, to the distillation residue and the amount of liquid. For example, the distillation residue and the amount of liquid may be subjected to stirring, shaking, sonication, centrifugation, etc.

[0029] After a precipitate has been separated from an amount of liquid, the liquid may be disposed of and / or recovered and optionally reused in any suitable manner. For example, if the liquid includes water, then the water may be subjected to a wastewater treatment process. As a further example, if the liquid includes an organic liquid, such as an alcohol, theFI2353 PCT Attorney Docket No.92230-0372 liquid may be (i) subjected to a distillation process, and optionally reused in the methods provided herein, or (ii) disposed of in any suitable manner.

[0030] Material of Interest

[0031] The at least one material of interest recovered by the methods provided herein generally may be any one or more components of a byproduct stream. The at least one material of interest may include a first material of interest, a second material of interest, a third material of interest, etc., or any combination thereof.

[0032] In some embodiments, the at least one material of interest includes a catalyst, such as a transesterification catalyst, a polymerization inhibitor, or a combination thereof. The catalyst may include a dialkyl metal oxide, such as DBTO. The polymerization inhibitor may include phenothiazine (PTZ).

[0033] Further Method Steps

[0034] When the at least one material of interest includes two or more materials of interest, such as a first material of interest and a second material of interest, then the two or more materials of interest may be used together, without separating the two or more materials of interest. Therefore, the methods provided herein may also include contacting the two or more materials of interest and one or more reactants. The one or more reactants may include those used in a process for producing a polymerizable monomer or a precursor thereof, such as an acrylate or methacrylate monomer, for example, a process for producing dimethylaminoethyl acrylate (ADAME), dimethylaminoethyl methacrylate, etc.

[0035] When the at least one material of interest includes two or more materials of interest, such as a first material of interest and a second material of interest, then the two or more materials of interest may be separated from each other. The separating may be achieved using any known technique and / or apparatuses. In some embodiments, the separating of two or more materials of interest, such as the first material of interest and the second material of interest, includes a liquid-solid extraction. For example, when a first material of interest includes DBTO, and a second material of interest includes PTZ, the separating of the first material of interest and the second material of interest may include contacting the first and the second material of interest with an organic liquid, preferably a polar organic liquid, such as acetone, in which the PTZ is soluble.

[0036] Recovered Materials of Interest

[0037] The one or more materials of interest recovered by the methods described herein may have a relatively high purity.FI2353 PCT Attorney Docket No.92230-0372

[0038] In some embodiments, a first material of interest (such as after the separating of two or more materials of interest) (e.g., DBTO) is at least 95 %, at least 99 %, or at least 99.99 % pure, by weight. In some embodiments, a second material of interest (such as after the separating of the first and the second material of interest) (e.g., PTZ) is at least 95 %, at least 99 %, or at least 99.99 % pure, by weight.

[0039] All referenced publications are incorporated herein by reference in their entirety. Furthermore, where a definition or use of a term in a reference, which is incorporated by reference herein, is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.

[0040] While certain aspects of conventional technologies have been discussed to facilitate disclosure of various embodiments, applicants in no way disclaim these technical aspects, and it is contemplated that the present disclosure may encompass one or more of the conventional technical aspects discussed herein.

[0041] The present disclosure may address one or more of the problems and deficiencies of known methods and processes. However, it is contemplated that various embodiments may prove useful in addressing other problems and deficiencies in a number of technical areas. Therefore, the present disclosure should not necessarily be construed as limited to addressing any of the particular problems or deficiencies discussed herein.

[0042] In this specification, where a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was at the priority date, publicly available, known to the public, part of common general knowledge, or otherwise constitutes prior art under the applicable statutory provisions; or is known to be relevant to an attempt to solve any problem with which this specification is concerned.

[0043] In the descriptions provided herein, the terms “includes,” “is,” “containing,” “having,” and “comprises” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to.” When compositions or methods are claimed or described in terms of “comprising” various steps or components, the compositions or methods can also “consist essentially of” or “consist of” the various steps or components, unless stated otherwise.

[0044] The terms “a,” “an,” and “the” are intended to include plural alternatives, e.g., at least one. For instance, the disclosure of “a byproduct stream”, “a material of interest”, andFI2353 PCT Attorney Docket No.92230-0372 the like, is meant to encompass one, or mixtures or combinations of more than one byproduct stream, material of interest, and the like, unless otherwise specified.

[0045] Various numerical ranges may be disclosed herein. When Applicant discloses or claims a range of any type, Applicant’s intent is to disclose or claim individually each possible number that such a range could reasonably encompass, including end points of the range as well as any sub-ranges and combinations of sub-ranges encompassed therein, unless otherwise specified. Moreover, all numerical end points of ranges disclosed herein are approximate. As a representative example, Applicant discloses, in some embodiments, a temperature of about 30 °C to about 50 °C. This range should be interpreted as encompassing a temperature of about 30 °C, a temperature of about 50 °C, and further encompasses temperatures of about 31 °C, about 32 °C, about 33 °C, about 34 °C, about 35 °C, about 36 °C, about 37 °C, about 38 °C, about 39 °C, about 40 °C, about 41 °C, about 42 °C, about 43 °C, about 44 °C, about 45 °C, about 46 °C, about 47 °C, about 48 °C, or about 49 °C, including any ranges and sub-ranges between any of these values.

[0046] As used herein, the term “about” means plus or minus 10 % of the numerical value of the number with which it is being used.

[0047] Throughout the application, including the examples, the following abbreviations are used. Abbreviation CompoundFI2353 PCT Attorney Docket No.92230-0372

[0048] Examples

[0049] The present disclosure is further illustrated by the following examples, which are not to be construed in any way as imposing limitations upon the scope thereof. On the contrary, it is to be clearly understood that resort may be had to various other aspects, embodiments, modifications, and equivalents thereof which, after reading the description herein, may suggest themselves to one of ordinary skill in the art without departing from the spirit of the present disclosure or the scope of the appended claims. Thus, other aspects of this disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the embodiments disclosed herein.

[0050] Example 1 – Comparative

[0051] A side stream from a process that produced dimethylaminoethylacrylate was distilled directly in vacuum in this example. The composition of the side stream prior to the distillation is shown in the following table.

[0052] Table 1. Composition of Side Stream Prior to Distillation Material Percentage (wt%)FI2353 PCT Attorney Docket No.92230-0372 DMETO-ADAME 32.7 Other 15.9bottomed flask, an electric heater, a thermometer, a cold condenser, a vacuum line, a cooled collection flask, and a cold trap. The temperature and vacuum were controlled and measured. The fractions collected into the collection flask and cold trap in different conditions were weighed and analyzed. The various conditions are depicted in the following table.

[0054] Table 2. Conditions of Distillations of Example 1 Fraction Temperature Pressure Duration of Amount (°C) (mBar) Collection collected (g)p p g e.

[0056] Table 3. Compositions of Fractions Fraction MeOH MA DMEA 3- ADAME MEPAME Anti- DMETO- (g) (g) (g) MMP (g) (g) MEPAME ADAME

[0057] The bottom fraction of the distillation included about 24 %, by weight, of the original material. The bottom fraction was a black hard “chunk” that did not dissolve in hot water, cold water, or a number of common laboratory solvents.

[0058] This example demonstrated that using a conventional direct distillation method separated about 76 %, by weight, of the volatile materials, but 24 %, by weight, of the non- volatile materials were essentially useless solid wastes that could not be easily subjected to further processing.FI2353 PCT Attorney Docket No.92230-0372

[0059] Example 2 – Embodiment of a Distillation

[0060] In this example, a side stream from a process that produces dimethylaminoethylacrylate was subjected to a short path distillation under high vacuum. The composition of the side stream prior to the distillation is shown in the following table.

[0061] Table 4. Composition of Side Stream Prior to Distillation Material Percentage (wt%) Methanol 0, c heater, a thermometer, a cold condenser, a vacuum line, a cooled collection flask, and cold trap. The temperature and vacuum were controlled and measured. The fractions collected into the collection flask and cold trap in different conditions were weighed and analyzed. The conditions of the fractions are shown in the following table.

[0063] Table 5. Conditions of Distillation of Example 2 boiling point analysis, wt.% range / pressure O- E

[0064] All fractions of the distillation of this example, including the bottom fraction, were homogeneous liquids.

[0065] The bottom fraction of this example was washed with water, and a white precipitate formed during the washing. The precipitate was recovered via filtration as a fine powder.

[0066] EmbodimentsFI2353 PCT Attorney Docket No.92230-0372

[0067] The following is a non-limiting listing of embodiments of the methods described herein.

[0068] Embodiment 1. A method of recovering a material, the method comprising, consisting essentially of, or consisting of –

[0069] providing a byproduct stream;

[0070] subjecting the byproduct stream to a distillation at a temperature and a vacuum pressure effective to separate from the byproduct stream at least a portion of one or more volatile compounds, thereby forming a distillation residue; and

[0071] contacting the distillation residue and an amount of a liquid effective to form a precipitate, wherein the precipitate comprises, consists essentially of, or consists of at least one material of interest.

[0072] Embodiment 2. The method of Embodiment 1, further comprising, consisting essentially of, or consisting of separating the precipitate from the amount of the liquid.

[0073] Embodiment 3. The method of any of the preceding embodiments, wherein the liquid comprises, consists essentially of, or consists of water, an organic liquid, or a combination thereof; wherein, optionally, the organic liquid is miscible with water; and / or wherein, optionally, the organic liquid comprises, consists essentially of, or consists of an alcohol, such as an alcohol of formula ROH, wherein R is a C1-C6 hydrocarbyl (e.g., methanol, ethanol, propanol (n-propanol and / or isopropanol), butanol (n-butanol, isobutanol, tert-butanol, and / or sec-butanol), or a combination thereof).

[0074] Embodiment 4. The method of Embodiment 3, wherein when the liquid comprises, consists essentially of, or consists of water, the method further comprises, consists essentially of, or consists of subjecting the amount of water to a wastewater treatment process.

[0075] Embodiment 5. The method of any of the preceding embodiments, wherein the pH of the amount of the liquid is 7 or less, less than 7, or about 5 to about 7.

[0076] Embodiment 6. The method of any of the preceding embodiments, wherein the amount of the liquid is at ambient temperature prior to the contacting of the distillation residue and the amount of water.

[0077] Embodiment 7. The method of any of the preceding embodiments, wherein the contacting of the distillation residue and the amount of the liquid occurs after the distillation and before the distillation residue has cooled to ambient temperature.

[0078] Embodiment 8. The method of any of the preceding embodiments, wherein the contacting of the distillation residue and the amount of the liquid comprises, consistsFI2353 PCT Attorney Docket No.92230-0372 essentially of, or consists of applying one or more forces, e.g., mixing forces, to the distillation residue and the amount of the liquid; wherein, optionally, the applying of the one or more forces comprises, consists essentially of, or consists of stirring, shaking, sonication, centrifugation, etc.

[0079] Material of Interest

[0080] Embodiment 9. The method of any of the preceding embodiments, wherein the at least one material of interest comprises, consists essentially of, or consists of a catalyst, such as a transesterification catalyst.

[0081] Embodiment 10. The method of any of the preceding embodiments, wherein the catalyst comprises, consists essentially of, or consists of a dialkyl metal oxide.

[0082] Embodiment 11. The method of any of the preceding embodiments, wherein the catalyst comprises, consists essentially of, or consists of dibutyl tin oxide (DBTO).

[0083] Embodiment 12. The method of any of the preceding embodiments, wherein the at least one material of interest comprises, consists essentially of, or consists of a polymerization inhibitor.

[0084] Embodiment 13. The method of any of the preceding embodiments, wherein the polymerization inhibitor comprises, consists essentially of, or consists of phenothiazine (PTZ).

[0085] Further Method Steps

[0086] Embodiment 14. The method of any of the preceding embodiments, wherein when the at least one material of interest comprises, consists essentially of, or consists of a first material of interest and a second material of interest, the method further comprises, consists essentially of, or consists of (i) contacting the first material of interest, the second material of interest, and one or more reactants, or (ii) contacting (a) the first material of interest or the second material of interest, and (b) one or more reactants.

[0087] Embodiment 15. The method of any of the preceding embodiments, wherein the one or more reactants are those used in a process for producing a polymerizable monomer or a precursor thereof, such as an acrylate or methacrylate monomer, for example, a process for producing dimethylaminoethyl acrylate (ADAME), dimethylaminoethyl methacrylate, etc.

[0088] Embodiment 16. The method of any of the preceding embodiments, wherein when the at least one material of interest comprises, consists essentially of, or consists of a first material of interest and a second material of interest, the method further comprises, consists essentially of, or consists of separating the first material of interest and the second material of interest.FI2353 PCT Attorney Docket No.92230-0372

[0089] Embodiment 17. The method of any of the preceding embodiments, wherein the separating of the first material of interest and the second material of interest comprises, consists essentially of, or consists of a liquid-solid extraction.

[0090] Embodiment 18. The method of any of the preceding embodiments, wherein when the first material of interest comprises, consists essentially of, or consists of DBTO, and the second material of interest comprises, consists essentially of, or consists of PTZ, the separating of the first material of interest and the second material of interest comprises, consists essentially of, or consists of contacting the first and the second material of interest with an organic liquid, preferably a polar organic liquid, such as acetone, in which the PTZ is soluble.

[0091] Embodiment 19. The method of any of the preceding embodiments, wherein the first material of interest (such as after the separating of the first and the second material of interest) (e.g., DBTO) is at least 95 %, at least 99 %, or at least 99.99 % pure, by weight.

[0092] Embodiment 20. The method of any of the preceding embodiments, wherein the second material of interest (such as after the separating of the first and the second material of interest) (e.g., PTZ) is at least 95 %, at least 99 %, or at least 99.99 % pure, by weight.

[0093] Temperature

[0094] Embodiment 21. The method of any of the preceding embodiments, wherein the temperature is about 100 °C or less, about 95 °C or less, about 90 °C or less, about 85 °C or less, about 80 °C or less, about 75 °C or less, about 70 °C or less, about 65 °C or less, or about 60 °C or less.

[0095] Embodiment 22. The method of any of the preceding embodiments, wherein the temperature is about 30 °C to about 100 °C, about 30 °C to about 95 °C, about 30 °C to about 90 °C, about 30 °C to about 85 °C, about 30 °C to about 80 °C, about 30 °C to about 75 °C, about 30 °C to about 70 °C, about 30 °C to about 65 °C, about 30 °C to about 60 °C, about 30 °C to about 55 °C, about 30 °C to about 50 °C.

[0096] Vacuum Pressure

[0097] Embodiment 23. The method of any of the preceding embodiments, wherein the vacuum pressure is about 100 millibars or less, 75 millibars or less, 50 millibars or less, 25 millibars or less, about 15 millibars or less, about 10 millibars or less, about 8 millibars or less, about 6 millibars or less, about 4 millibars or less, about 2 millibars or less, about 1 millibar or less, about 0.5 millibars or less, or about 0.1 millibars or less.

[0098] Byproduct StreamFI2353 PCT Attorney Docket No.92230-0372

[0099] Embodiment 24. The method of any of the preceding embodiments, wherein the byproduct stream is from a process that produces a polymerizable monomer or a precursor thereof, such as an acrylate monomer or a methacrylate monomer.

[0100] Embodiment 25. The method of any of the preceding embodiments, wherein the byproduct stream is from a process for producing dimethylaminoethyl acrylate (ADAME).

[0101] Embodiment 26. The method of any of the preceding embodiments, wherein the byproduct stream comprises, consists essentially of, or consists of methyl 3-(2- (dimethylamino)ethoxy)propanoate, ethyl 3-(2-(dimethylamino)ethoxy)propanoate, 2- (dimethylamino)ethyl 3-methoxypropanoate, 2-(dimethylamino)ethyl 3-ethoxypropanoate, 2- (dimethylamino)ethyl 3-(2-(dimethylamino)ethoxy)propanoate, 2-(dimethylamino)ethyl acrylate, 2-(dimethylamino)ethan-1-ol, methyl 3-methoxypropanoate, ethyl 3- ethoxypropanoate, or a combination thereof: . wherein the

[0103] Embodiment 28. The method of any of the preceding embodiments, wherein the byproduct stream comprises, consists essentially of or consists of 2-(dimethylamino)ethyl 3-FI2353 PCT Attorney Docket No.92230-0372 methoxy-2-methylpropanoate, methyl 3-[2-(dimethylamino)ethoxy]-2-methylpropanoate, 2- (dimethylamino)ethyl 3-[2-(dimethylamino)ethoxy]-2-methylpropanoate, 2- (dimethylamino)ethyl methacrylate, 2-(dimethylamino)ethan-1-ol, or a combination thereof:

Claims

FI2353 PCT Attorney Docket No.92230-0372 We claim - 1. A method of recovering a material, the method comprising – providing a byproduct stream; subjecting the byproduct stream to a distillation at a temperature and a vacuum pressure effective to separate from the byproduct stream at least a portion of one or more volatile compounds, thereby forming a distillation residue; and contacting the distillation residue and an amount of a liquid effective to form a precipitate, wherein the precipitate comprises at least one material of interest, wherein the at least one material of interest comprises a catalyst, a polymerization inhibitor, or a combination thereof.

2. The method of claim 1, wherein the at least one material of interest comprises the catalyst.

3. The method of claim 2, wherein the catalyst is a transesterification catalyst.

4. The method of claim 3, wherein the transesterification catalyst is a dialkyl metal oxide.

5. The method of claim 2, wherein the catalyst is dibutyl tin oxide (DBTO).

6. The method of claim 1, wherein the polymerization inhibitor is phenothiazine (PTZ).

7. The method of claim 1, wherein the at least one material of interest comprises a first material of interest and a second material of interest, and the method further comprises contacting the first material of interest, the second material of interest, and one or more reactants.

8. The method of claim 1, wherein the at least one material of interest comprises a first material of interest and a second material of interest, and the method further comprises separating the first material of interest and the second material of interest.FI2353 PCT Attorney Docket No.92230-0372 9. The method of claim 8, wherein the separating of the first material of interest and the second material of interest comprises a liquid-solid extraction.

10. The method of claim 8, wherein, after the separating of the first material of interest and the second material of interest, the first material of interest is at least 95 % pure, by weight.

11. The method of claim 10, wherein, after the separating of the first material of interest and the second material of interest, the second material of interest is at least 95 % pure, by weight.

12. The method of claim 1, wherein the temperature is about 100 °C or less, and the vacuum pressure is about 10 millibars or less.

13. The method of claim 1, wherein the temperature is about 30 °C to about 80 °C, and the vacuum pressure is about 1 millibar or less.

14. The method of claim 1, wherein the byproduct stream is from a process that produces a polymerizable monomer or a precursor thereof.

15. The method of claim 1, wherein the byproduct stream is from a process for producing dimethylaminoethyl acrylate (ADAME) or dimethylaminoethyl methacrylate.

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