Methods for reducing and preventing polymer fouling and agglomeration in processes for producing ethylenically unsaturated monomers and compositions related thereto

Abstract

This document relates to methods of reducing and preventing polymer fouling and agglomeration in processes for producing ethylenically unsaturated monomers and compositions related thereto. A method of reducing polymer fouling in a process fluid in contact with process equipment used to make ethylenically unsaturated monomers, and the like, is provided. The method includes contacting the polymer fouling in the process fluid with a water-soluble polymer having the structural formula I, wherein E is a repeat unit from a polymerizable ethylenically unsaturated monomer; R1 and R2 are independently H or C1-C4 alkyl; X is OR, OOR, OM, NH2, NH-R, or NH-O-R; Y is SO3M or OSO3M; Q is C1-C4 alkylene or carbonyl; P is O, NH, or NR; R3 is C1-C 100 alkyl, C2-C 100 alkylene, C1-C 100 hydroxy-substituted alkyl moiety, or C2-C 100 hydroxy-substituted alkylene moiety; M is hydrogen or a water-soluble cation; R is alkyl; a is 0-100; and the mole ratio of b:c is 30:1 to 1:20.

Description

Technical Field

[0001] A method for reducing polymer fouling in process fluids that come into contact with process equipment used to prepare olefinic unsaturated monomers, a method for preventing polymer deposition on process equipment that comes into contact with process fluids used to prepare olefinic unsaturated monomers, and a composition for reducing polymer fouling. Background Technology

[0002] This disclosure relates to methods and compositions for reducing polymer fouling and agglomeration in the preparation process of olefinic unsaturated monomers and for preventing polymer tar-like deposits in process and storage equipment used in the production of olefinic unsaturated monomers.

[0003] Numerous industrial methods are commonly used to prepare (meth)acrylates / salts, (meth)acrylic acid, (meth)acrylonitrile, and (meth)alkyl methacrylates / salts, such as methyl methacrylate / salt (MMA). Polymer formation, agglomeration, and fouling are typically concerns in methods for handling (meth)acrylates / salts, (meth)acrylic acid, or (meth)acrylonitrile. Fouling is caused by undesirable byproducts, which consist of a wide range of chemical compounds, including but not limited to oligomer and polymeric materials. These materials tend to agglomerate into large particles that can precipitate and deposit on process and storage equipment. These deposited materials are commonly referred to as “polymer tar” or simply “tar.” Ultimately, equipment shutdown and cleaning are required to remove the polymer fouling or tar.

[0004] Reducing or preventing polymer fouling and the operational problems caused by polymer fouling is challenging.

[0005] U.S. Patent No. 9,884,951 describes a method for using an organic solvent, such as dimethyl phthalate, to disperse or dissolve polymer tar in an MMA preparation process.

[0006] PCT Publication No. WO 2015 / 140549 describes a method for using alkoxyimidazoline as a tar dispersant in the MMA preparation process.

[0007] US Patent No. 7,005,087 describes a method for using alkylaminoimidazoline as a tar dispersant in the MMA preparation process. Summary of the Invention

[0008] This disclosure relates to a method for removing and preventing polymer fouling and tar accumulation and clogging in process equipment used to produce olefinic unsaturated monomers such as (meth)acrylates / salts, (meth)acrylic acid, or (meth)acrylonitrile.

[0009] In one aspect, a method is provided for reducing polymer fouling in process fluids that come into contact with process equipment used to prepare olefinically unsaturated monomers. The method involves contacting the polymer fouling in the process fluid with a water-soluble polymer having structural formula I:

[0010]

[0011] Where E is a repeating unit derived from a polymerizable olefinically unsaturated monomer, such as, but not limited to, acrylic acid;

[0012] R1 and R2 are independently H or C1-C4 alkyl;

[0013] X is OR, OOR, OM, NH2, NH-R, or NH-OR;

[0014] Y is SO3M or OSO3M;

[0015] Q is a C1-C4 alkylene or carbonyl group;

[0016] P is O, NH, or NR; R3 is Cl-C 100 Alkyl, C2-C 100 Alkylene, C1-C 100 hydroxyl-substituted alkyl moiety or C2-C 100 The hydroxyl-substituted alkylene moiety;

[0017] M is hydrogen or a water-soluble cation;

[0018] R is an alkyl group;

[0019] a is 0-100;

[0020] Furthermore, the molar ratio of b to c is between 30:1 and 1:20.

[0021] On the other hand, a method is provided to prevent polymer deposition on process equipment in contact with a process fluid used to prepare an olefinically unsaturated monomer. The method includes contacting polymer contaminants in the process fluid with a water-soluble polymer having structural formula I.

[0022]

[0023] Where E is a repeating unit derived from a polymerizable olefinically unsaturated monomer, such as, but not limited to, acrylic acid;

[0024] R1 and R2 are independently H or C1-C4 alkyl;

[0025] X is OR, OOR, OM, NH2, NH-R, or NH-OR;

[0026] Y is SO3M or OSO3M;

[0027] Q is a C1-C4 alkylene or carbonyl group;

[0028] P is O, NH, or NR; R3 is Cl-C 100 Alkyl, C2-C 100 Alkylene, C1-C 100 hydroxyl-substituted alkyl moiety or C2-C 100 The hydroxyl-substituted alkylene moiety;

[0029] M is hydrogen or a water-soluble cation;

[0030] R is an alkyl group;

[0031] a is 0-100;

[0032] Furthermore, the molar ratio of b to c is between 30:1 and 1:20.

[0033] On the other hand, a composition for reducing polymer fouling and preventing polymer deposition is provided. The composition comprises a water-soluble polymer having structural formula I:

[0034]

[0035] Where E is a repeating unit derived from a polymerizable olefinically unsaturated monomer, such as, but not limited to, acrylic acid;

[0036] R1 and R2 are independently H or C1-C4 alkyl;

[0037] X is OR, OOR, OM, NH2, NH-R, or NH-OR;

[0038] Y is SO3M or OSO3M;

[0039] Q is a C1-C4 alkylene or carbonyl group;

[0040] P is O, NH, or NR; R3 is Cl-C 100 Alkyl, C2-C 100 Alkylene, C1-C 100 hydroxyl-substituted alkyl moiety or C2-C 100 The hydroxyl-substituted alkylene moiety;

[0041] M is hydrogen or a water-soluble cation;

[0042] R is an alkyl group;

[0043] a is 0-100;

[0044] Furthermore, the molar ratio of b to c is between 30:1 and 1:20.

[0045] This technology describes methods and compositions for dispersing tar in the production of olefin saturated monomers, such as (meth)acrylic acid, (meth)acrylate / salt, and (meth)acrylonitrile. The disclosed methods disperse and dissolve hydrocarbon contaminants, prevent tar accumulation on processing and storage equipment, and remove polymer build-up and deposits from the manufacturing process. Attached Figure Description

[0046] The features and advantages of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings, wherein:

[0047] Figure 1 This is a schematic diagram of the process equipment used in a typical methyl methacrylate / salt process; and Figure 2 Images of sample AG from the examples are described. Detailed Implementation Plan

[0048] When describing elements of the invention or one or more embodiments thereof, the articles “a”, “an”, and “the” are intended to indicate the presence of one or more elements. Similarly, the adjective “another” when used to introduce an element is intended to indicate one or more elements. The terms “comprising” and “having” are intended to be inclusive, such that additional elements may be present in addition to those listed. The term “exemplary” should not be construed as a superlative example, but merely one of many possible examples.

[0049] The term “about” as used throughout this specification is used to describe and explain small fluctuations. For example, the term “about” can mean less than or equal to ±5%, such as less than or equal to ±2%, less than or equal to ±1%, less than or equal to ±0.5%, less than or equal to ±0.1%, or less than or equal to ±0.05%. All numerical values ​​herein are modified by the term “about”, whether explicitly stated or not. Values ​​modified by the term “about” naturally include specific values. For example, “about 5.0” must include 5.0.

[0050] "(Methacrylamide)" refers to acrylamide and methacrylamide.

[0051] "(Meth)acrylic acid" refers to methacrylic acid and acrylic acid.

[0052] "(Methacrylonitrile)" refers to both methacrylonitrile and acrylonitrile.

[0053] The production method for preparing (meth)acrylic acid, (meth)acrylamide, or (meth)acrylonitrile refers to the method for preparing (meth)acrylic acid, (meth)acrylamide, or (meth)acrylonitrile, and includes the amide stage, the thermal conversion stage, the waste acid stream formed during the thermal conversion stage, the recovery and purification process of the preparation method, and storage.

[0054] Unless otherwise stated herein, “acrylate / salt” means a salt or ester of acrylic acid.

[0055] Unless otherwise stated herein, “methacrylate / salt” means a salt or ester of methacrylic acid. Methacrylate / salt may include alkyl methacrylate / salts, such as methyl methacrylate / salt, ethyl methacrylate / salt, and butyl methacrylate / salt.

[0056] This disclosure provides polymer dispersants for use in methods for preparing (meth)acrylonitrile, (meth)acrylate / salts, or (meth)acrylic acid. The inventors have discovered a novel polymer for dispersing polymer fouling and oligomer fouling generated in methods for preparing olefinically unsaturated monomers such as (meth)acrylic acid, (meth)acrylate / salts, and / or (meth)acrylonitrile. Compared to other known dispersants, this novel polymer dispersant exhibits improved effectiveness in dispersing polymer tar and maintaining polymer fouling particles at a small size, thereby preventing or reducing the risk of polymer fouling or polymer tar deposition and equipment clogging.

[0057] In one aspect, a method is provided for reducing polymer fouling in process fluids that come into contact with process equipment used to prepare olefinically unsaturated monomers. This method involves contacting the polymer fouling with a water-soluble polymer having structural formula I:

[0058]

[0059] Where E is a repeating unit derived from a polymerizable olefinically unsaturated monomer, such as, but not limited to, acrylic acid;

[0060] R1 and R2 are independently H or C1-C4 alkyl;

[0061] X is OR, OOR, OM, NH2, NH-R, or NH-OR;

[0062] Y is SO3M or OSO3M;

[0063] Q is a C1-C4 alkylene or carbonyl group;

[0064] P is O, NH, or NR; R3 is Cl-C 100 Alkyl, C2-C 100 Alkylene, C1-C 100 hydroxyl-substituted alkyl moiety or C2-C 100 The hydroxyl-substituted alkylene moiety;

[0065] M is hydrogen or a water-soluble cation;

[0066] R is an alkyl group;

[0067] a is 0-100;

[0068] Furthermore, the molar ratio of b to c is between 30:1 and 1:20.

[0069] In some embodiments, the olefinic unsaturated monomer is (meth)acrylic acid, (meth)acrylate / salt, or (meth)acrylonitrile.

[0070] In some embodiments, the number-average molecular weight of the water-soluble polymer of Formula I falls within the range of 1,000 to 1,000,000. In another embodiment, the number-average molecular weight is in the range of about 10,000 to 500,000. In some embodiments, the number-average molecular weight is in the range of about 5,000 to 20,000. In other embodiments, the number-average molecular weight is in the range of about 20,000 to about 100,000.

[0071] E is an optional repeating monomer unit. In some embodiments, E is acrylic acid. In some embodiments, a is 0, and the water-soluble polymer having Formula I is a copolymer. In other embodiments, a is positive, and the water-soluble polymer is a terpolymer. In some embodiments, a is in the range of about 1 to 100. In other embodiments, a is in the range of about 1 to 50; and in other embodiments, a is about 1 to 25.

[0072] R is an alkyl group. In some embodiments, R is C1-C. 100 Alkyl group. In other embodiments, R is C1-C6. 50 Alkyl group. In other embodiments, R is C1-C6. 20 Alkyl group. In some embodiments, R is C1-C2. 10 Alkyl group, and in other embodiments, R is a C1-C5 alkyl group. In another embodiment, R is a C1-C4 alkyl group.

[0073] In some implementations, R3 is C1-C 50 Alkyl group. In other embodiments, R3 is C1-C6. 20 Alkyl group. In some embodiments, R3 is C1-C. 10 Alkyl group, and in other embodiments, R3 is a C1-C5 alkyl group. In another embodiment, R3 is a C1-C4 alkyl group.

[0074] In some implementations, R3 is C2-C 50 Alkylene. In other embodiments, R3 is C2-C. 20 Alkylene. In some embodiments, R3 is C2-C. 10 Alkylene, and in other embodiments, R3 is a C2-C4 alkylene.

[0075] In some implementations, R3 is C1-C 50 A hydroxyl-substituted alkyl moiety. In other embodiments, R3 is C1-C6. 20 Hydroxyl-substituted alkyl moiety. In some embodiments, R3 is C1-C. 10 The alkyl moiety is hydroxylated, and in other embodiments, R3 is a C1-C5 hydroxylated alkyl moiety. In another embodiment, R3 is a C1-C4 alkyl moiety.

[0076] In some implementations, R3 is C2-C 50 A hydroxyl-substituted alkylene moiety. In other embodiments, R3 is C2-C6. 20 Hydroxyl-substituted alkylene moiety. In some embodiments, R3 is C2-C. 10 The hydroxylated alkylene moiety, and in other embodiments, R3 is a C2-C4 hydroxylated alkylene moiety.

[0077] In one embodiment, M is a water-soluble cation, such as an alkali metal, ammonium, or a substituted ammonium cation. In one embodiment, the molar ratio b:c is from 30:1 to 1:20. In another embodiment, the molar ratio b:c is from about 10:1 to 1:5.

[0078] In one embodiment, the polymer having Formula I is an acrylic acid / allyl hydroxypropyl sulfonate / salt ether (AA / AHPSE) copolymer. The copolymer having Formula I can be prepared by reacting allyl alcohol with a tertiary alcohol at a temperature ranging from about 25°C to 150°C, followed by monomer sulfonation using known techniques.

[0079] The water-soluble polymer having Formula I is a dispersant polymer that reduces and removes hydrocarbon fouling formed in production methods for preparing olefinic unsaturated monomers such as (meth)acrylates / salts, (meth)acrylic acid, or (meth)acrylonitrile.

[0080] Many commercially known methods are used to prepare (meth)acrylates / salts, (meth)acrylic acid, and (meth)acrylonitrile. In one method, gas-phase catalytic oxidation is used with an alkane, olefin, alkanol, or enal containing 3 to 4 carbon atoms. (One such method is described in U.S. Patent No. 7,005,087.) The reaction products from the oxidation process are separated and methacrylic acid and acrylic acid are purified in a recovery and purification section, which includes extraction and distillation separation. The effluent from the oxidation process is cooled in an absorber to remove light components from the product effluent, and in an extraction column, methacrylic acid and / or acrylic acid are concentrated by removing water or acetic acid, or both, with a selected solvent. The crude methacrylic acid or acrylic acid stream or waste acid stream is then purified in a subsequent distillation column to remove residual extraction solvent and reaction byproducts.

[0081] Currently, the most widely practiced method for the continuous production of alkyl methacrylates / salts such as methyl methacrylate / salt (MMA) or methacrylic acid (MAA) is known as the "acetone cyanohydrin (ACH) route." Typically, in the ACH route, acetone cyanohydrin is added to an excess of concentrated sulfuric acid, which acts as both a reactant and a solvent. The reaction between ACH and sulfuric acid produces a mixture of sulfate isobutyramide (SIBAM) and hydroxyisobutyramide (HIBAM). This amide mixture is then thermally converted to methacrylamide (MAM) and a small amount of MAA, still in solution form in concentrated sulfuric acid. The process steps from the initial mixing of ACH with concentrated sulfuric acid to the thermal conversion of SIBAM and HIBAM to MAM can be referred to as the "amide stage" of the process. The temperature can be from about 90°C to about 150°C.

[0082] In one embodiment, methacrylic acid is prepared by mixing the product of the amide stage of the ACH process, a concentrated sulfuric acid solution of MAM, and water, thereby producing MAA via the hydrolysis of MAM. In another embodiment, MMA is prepared by mixing the product of the amide stage of the ACH process, a concentrated sulfuric acid solution of MAM, with water and methanol, thereby producing MMA via a combination of hydrolysis and esterification of MAM. In one embodiment, the reaction with the amide stage can be carried out in one or more reactors at a temperature of about 100°C to 150°C. In one embodiment, the reactor is a continuous reactor.

[0083] To facilitate the thermal conversion of SIBAM and HIBAM to MAM, heat and residence time are typically required. Unfortunately, undesirable byproducts are also formed, especially during the high-temperature thermal conversion phase. These undesirable byproducts consist of a wide range of chemical components, including many sulfonated compounds as well as hydrocarbon compounds, such as oligomers and polymers. Polymers and oligomers are carried out with the process along with an aqueous sulfuric acid stream known as “waste acid,” and agglomerate into large particles that precipitate from the waste acid or deposit on the equipment. The formation, agglomeration, and scaling of polymers are typically a concern in processes involving acrylate / salt, methacrylic acid, or methacrylate / salt materials. The deposited material is often referred to by those skilled in the art as “polymer tar” or simply “tar.” Therefore, reducing or preventing operational problems caused by polymers in waste acid is challenging.

[0084] In this technology, it has been determined that by adding the polymer of Formula I to a waste acid stream, the agglomeration and deposition of polymer tar during the preparation of (meth)acrylonitrile, (meth)acrylate / salt, or (meth)acrylic acid is reduced or prevented. When the polymer tar or hydrocarbon contaminant is small in size, the dispersant polymer of Formula I adsorbs onto the surface of the polymer tar, which makes the deposit or tar more dispersible in the acid stream and prevents further agglomeration.

[0085] In one embodiment, the waste acid comes into contact with process equipment. Process equipment may include, but is not limited to, conventional equipment used in the manufacture of acrylates / salts, methacrylates / salts, or methacrylic acid, including reactors, reaction vessels, piping systems, pipelines, storage facilities, storage tanks, and recovery equipment.

[0086] On the other hand, a method is provided to prevent polymer deposition on process equipment in contact with process fluids used to prepare olefinic unsaturated monomers. The method includes contacting polymer contaminants in the process fluid with a water-soluble polymer having the structural formula I as described above.

[0087] In some embodiments, the olefinic unsaturated monomer is (meth)acrylic acid, (meth)acrylate / salt, or (meth)acrylonitrile.

[0088] In another embodiment, the polymer having Formula I is an acrylic acid / allyl hydroxypropyl sulfonate / salt ether (AA / AHPSE) copolymer.

[0089] On the other hand, a composition for reducing polymer fouling and preventing polymer deposition is provided. The composition comprises a water-soluble polymer having the aforementioned structural formula I.

[0090] In some embodiments, the olefinic unsaturated monomer is (meth)acrylic acid, (meth)acrylate / salt, or (meth)acrylonitrile.

[0091] In one embodiment, the polymer having Formula I is an acrylic acid / allyl hydroxypropyl sulfonate / salt ether (AA / AHPSE) copolymer.

[0092] Figure 1 The process equipment and waste acid stream for a typical methacrylate / salt and / or methacrylic acid ACH manufacturing process 10 are shown. Waste acid stream 30 exits reactor 20. Waste acid stream 30 contains aqueous sulfuric acid and hydrocarbon fouling substances, such as oligomers and polymers. Waste acid stream 30 may flow to or be pumped to (1) storage tank 40 and / or (2) recovery unit 50 for further treatment.

[0093] In some embodiments, the water-soluble polymer of Formula I can be added to the waste acid stream 30 at various locations to treat the waste acid stream and prevent polymer tar deposition on the process equipment. In other embodiments, the water-soluble polymer of Formula I can be added to the waste acid stream at point A after leaving reactor 20 and before entering storage tank 40 or recovery unit 50; and in other embodiments, the water-soluble polymer of Formula I can be added to the waste acid stream in storage tank 40 (point B).

[0094] In some embodiments, the water-soluble polymer of Formula I can be fed intermittently or continuously. In some embodiments, the water-soluble polymer can be added to the waste acid stream in an amount from about 1 ppm to about 10,000 ppm. In another embodiment, the water-soluble polymer of Formula I can be added in an amount from about 100 ppm to about 5,000 ppm; and in other embodiments, from about 500 ppm to about 5,000 ppm. In yet another embodiment, the dosage of the water-soluble polymer of Formula I is from about 1,000 ppm to about 3,000 ppm.

[0095] Example

[0096] Example 1

[0097] Various dispersants were evaluated in a simulated waste acid solution. A polymer tar solution was prepared by dissolving 1 g of polymer tar in 100 mL of concentrated sulfuric acid. Waste acid was simulated using 20% ​​by weight sulfuric acid. The control dispersant and the dispersant of this invention were metered into the acid solution, thoroughly mixed, and preheated to 85°C. Then, the pre-prepared tar solution was added to the acid solution at a dosage of 50 ppm. The mixture was vigorously mixed and allowed to stand for observation. Polymer agglomeration was observed, and the effectiveness of each dispersant could be compared.

[0098] Comparative dispersants (AE) are shown in Table 1, and exemplary polymeric dispersant samples F and G are shown in Table 2. The number-average molecular weight of sample F is 5,000–20,000. The number-average molecular weight of sample G is 20,000–100,000.

[0099] Table 1. Comparison of dispersant samples

[0100] Comparison Samples dispersant A Dimethyl phthalate B Dimethyl alipate C Tall oil hydroxyethyl imidazoline D Copolymer of acrylic acid and 2-acrylamido-2-methylpropanesulfonic acid E Maleic anhydride / sodium diisobutylene polymer

[0101] Table 2. Dispersant compositions of the present invention

[0102] sample dispersant F Copolymer of acrylic acid and allyl hydroxypropyl sulfonate / salt G Copolymer of acrylic acid and allyl hydroxypropyl sulfonate / salt

[0103] For each sample, 2,000 ppm of dispersant sample AG was added. The agglomeration of polymer particles was observed for each sample, and the time for most particles to settle is recorded in Table 3.

[0104] (Timeout after 10 days)

[0105] Table 3: Results of MMA polymer tar dispersion study

[0106]

[0107]

[0108] Figure 2 The image shows the AG of the sample after a 6-hour settling time.

[0109] As the data show, dispersant samples F and G effectively controlled the agglomeration of polymer tar to maintain a very small particle size, thereby allowing the polymer tar to be dispersed in the test fluid for a longer period of time, compared to the control sample AE.

Claims

1. A method for reducing polymer fouling in a process fluid that comes into contact with process equipment used to prepare olefinic unsaturated monomers, the method comprising contacting polymer fouling in the process fluid with a water-soluble polymer having structural formula I: Where E is a repeating unit derived from polymerizable olefinic unsaturated monomers; R1 and R2 are independently H or C1-C4 alkyl; X is OR, OOR, OM, NH2, NH-R, or NH-OR; Y is SO3M or OSO3M; Q is a C1-C4 alkylene or carbonyl group; P is O, NH, or NR; R3 is Cl-C 100 Alkyl, C2-C 100 Alkylene, C1-C 100 hydroxyl-substituted alkyl moiety or C2-C 100 The hydroxyl-substituted alkylene moiety; M is hydrogen or a water-soluble cation; R is an alkyl group; a is 0-100; Furthermore, the molar ratio of b to c is between 30:1 and 1:

20.

2. The method according to claim 1, wherein the olefinic unsaturated monomer is at least one selected from acrylic acid, methacrylic acid, acrylate / salt, methacrylate / salt, acrylonitrile, and methacrylonitrile.

3. The method according to claim 2, wherein the methacrylate / salt is an alkyl methacrylate / salt.

4. The method according to claim 3, wherein the alkyl methacrylate / salt is methyl methacrylate / salt.

5. The method according to claim 1, wherein E is acrylic acid.

6. The method of claim 1, wherein a is 0.

7. The method according to claim 1, wherein the water-soluble polymer is an acrylate / salt / allyl hydroxypropyl sulfonate / salt ether copolymer.

8. The method according to claim 1, wherein the process fluid is a waste acid stream.

9. The method of claim 1, wherein the water-soluble polymer has a number average molecular weight of about 1,000 to about 1,000,000.

10. The method of claim 1, wherein the water-soluble polymer is added to the process fluid at a concentration of about 1 ppm to about 10,000 ppm.

11. A method for preventing polymer deposition on process equipment in contact with a process fluid used to prepare an olefinically unsaturated monomer, the method comprising contacting polymer contaminants in the process fluid with a water-soluble polymer having structural formula I: Where E is a repeating unit derived from polymerizable olefinic unsaturated monomers; R1 and R2 are independently H or C1-C4 alkyl; X is OR, OOR, OM, NH2, NH-R, or NH-OR; Y is SO3M or OSO3M; Q is a C1-C4 alkylene or carbonyl group; P is O, NH, or NR; R3 is Cl-C 100 Alkyl, C2-C 100 Alkylene, C1-C 100 hydroxyl-substituted alkyl moiety or C2-C 100 The hydroxyl-substituted alkylene moiety; M is hydrogen or a water-soluble cation; R is an alkyl group; a is 0-100; Furthermore, the molar ratio of b to c is between 30:1 and 1:

20.

12. The method according to claim 11, wherein the olefinic unsaturated monomer is at least one selected from acrylic acid, methacrylic acid, acrylate / salt, methacrylate / salt, acrylonitrile, and methacrylonitrile.

13. The method of claim 12, wherein the methacrylate / salt is an alkyl methacrylate / salt.

14. The method of claim 13, wherein the alkyl methacrylate / salt is methyl methacrylate / salt.

15. The method of claim 11, wherein E is acrylic acid.

16. The method of claim 11, wherein a is 0.

17. The method of claim 11, wherein the water-soluble polymer is an acrylate / salt / allyl hydroxypropyl sulfonate / salt ether copolymer.

18. The method according to claim 11, wherein the process fluid is a waste acid stream.

19. The method of claim 11, wherein the water-soluble polymer has a number-average molecular weight of about 1,000 to about 1,000,000.

20. The method of claim 11, wherein the water-soluble polymer is added to the process fluid at a concentration of about 1 ppm to about 10,000 ppm.

21. A composition for reducing polymer fouling, comprising a water-soluble polymer having structural formula I: Where E is a repeating unit derived from polymerizable olefinic unsaturated monomers; R1 and R2 are independently H or C1-C4 alkyl; X is OR, OOR, OM, NH2, NH-R, or NH-OR; Y is SO3M or OSO3M; Q is a C1-C4 alkylene or carbonyl group; P is O, NH, or NR; R3 is Cl-C 100 Alkyl, C2-C 100 Alkylene, C1-C 100 hydroxyl-substituted alkyl moiety or C2-C 100 The hydroxyl-substituted alkylene moiety; M is hydrogen or a water-soluble cation; R is an alkyl group; a is 0-100; Furthermore, the molar ratio of b to c is between 30:1 and 1:

20.

22. The composition according to claim 21, wherein E is acrylic acid.

23. The composition according to claim 21, wherein a is 0.

24. The composition of claim 21, wherein the water-soluble polymer is an acrylate / salt / allyl hydroxypropyl sulfonate / salt ether copolymer.

25. The composition of claim 21, wherein the number average molecular weight of the water-soluble polymer is about 1,000 to about 1,000,000.

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