Anti-freezing dispersant and process for producing the same

Abstract

The present disclosure provides methods of treating industrial processes with compositions, methods of making the compositions, and various anti-freeze compositions suitable for use in industrial processes. The anti-freeze dispersant compositions can include, for example, a sulfonated dispersant and a winterizing solvent. The anti-freeze dispersant compositions can prevent fouling in industrial processes.

Description

Background Technology

[0001] Dispersants and antifouling agents, used as colloidal stabilizers, can keep fouling in suspension and prevent it from depositing on equipment surfaces, and are widely used in various industrial applications. U.S. Patent No. 3,691,226 discloses an embodiment describing the use of lignin sulfonate metal salts to minimize fouling deposition on the heat transfer surfaces of heat exchangers in heaters used for cooling circulating water. Another embodiment is disclosed in U.S. Patent No. 5,650,072, which teaches the use of naphthalenesulfonic acid formaldehyde condensate polymers to prevent fouling in heat exchangers in acrylonitrile stripping towers. U.S. Patent No. 8,067,629 describes a process for the production of acrylonitrile, and more specifically, a process in which an antifouling dispersant comprising a polymer of styrene sulfonate is added to at least one step in the quenching, recovery, and wastewater treatment processes of the acrylonitrile manufacturing process.

[0002] Sulfonated dispersants are widely used in cement, textile and printing, pesticide, rubber, petroleum, and chemical production. Dispersants used in various manufacturing processes include sulfonated oils, sulfonated fatty acids, sulfated oils, sulfated fatty acids, naphthalenesulfonic acid formaldehyde, sulfonic acids, dodecylbenzenesulfonic acid, and lignin sulfates. However, dispersants are typically prepared as aqueous solutions, which solidify at approximately 0°C. This affects their transportation, storage, and application.

[0003] U.S. Patent No. 4,282,147 describes a method for forming a non-precipitated dispersion in an organic polyisocyanate using a finely divided solid aromatic isocyanate sulfonate diketone. Chinese Patent Application No. 201310733290.6 describes a method in which sodium isopropyl sulfonate is purified by removing sulfate using ethanol or glycerol. Chinese Patent Application No. 201510801942.4 describes a method for reducing sulfate content by adding hydrogen peroxide to sodium isopropyl sulfonate.

[0004] Embodiments of this disclosure relate to antifreeze dispersant compositions and manufacturing processes thereof to address solidification problems and thus allow the use of dispersants at low temperatures. Summary of the Invention

[0005] The compositions of some embodiments of this disclosure include a sulfonated dispersant and a solvent. The compositions may have a freezing point below about 0°C.

[0006] In some respects, the sulfonated dispersant is selected from the group consisting of: sulfonated oils, sulfonated fatty acids, naphthalenesulfonic acid formaldehyde condensates, styrene sulfonate polymers, and any combination thereof.

[0007] In some respects, the sulfonating dispersant is a sulfonic acid or a sulfonate.

[0008] In some aspects, the sulfonating dispersant is about 1 wt.% to about 60 wt.% of the composition.

[0009] In some respects, the solvent is selected from water, hydroxyl-functionalized compounds, and any combination thereof.

[0010] In some respects, the solvent is selected from the group consisting of water, ethylene glycol, glycerol, glycol ethers, and any combination thereof.

[0011] In some respects, the solvent comprises an amount ranging from about 1 wt.% to about 99 wt.% of alcohol.

[0012] In some respects, the solvent includes ethylene glycol.

[0013] In some respects, the sulfonating dispersant is a naphthalenesulfonic acid formaldehyde condensate.

[0014] In some respects, the naphthalenesulfonic acid formaldehyde condensate is 2-naphthalenesulfonic acid, a polymer with formaldehyde, or a salt thereof.

[0015] In some respects, the salt of the 2-naphthalenesulfonic acid, or the polymer with formaldehyde, is a sodium salt, potassium salt, ammonium salt, or a mixture thereof.

[0016] In some aspects, the composition comprises about 5 wt.% to about 20 wt.% of the sulfonated dispersant, and the solvent comprises about 40 wt.% to about 60 wt.% of ethylene glycol and about 20 wt.% to about 55 wt.% of water; or about 25 wt.% to about 45 wt.% of the sulfonated dispersant, and the solvent comprises about 10 wt.% to about 30 wt.% of ethylene glycol and about 25 wt.% to about 65 wt.% of water.

[0017] This disclosure also provides a method for preparing the compositions disclosed herein. The method may include dissolving the sulfonated dispersant in a solvent.

[0018] In some aspects, a method for preparing a composition includes: reacting naphthalene sulfonate with formaldehyde to form a sulfonated dispersant; purifying the sulfonated dispersant by adding a solvent to form a solution; separating a precipitate from the solution; drying the solution to form a powder; and dissolving the powder in a second solvent.

[0019] In some respects, the solvent is a poor solvent for sulfates.

[0020] In some respects, the solvent is methanol.

[0021] This disclosure also provides a method for reducing scaling during industrial processes. The method may include adding a composition comprising a sulfonating dispersant and a solvent to an aqueous medium during the industrial process.

[0022] In some respects, the industrial process is a chemical manufacturing process.

[0023] In some respects, the chemical manufacturing process is an acrolein manufacturing process, an acrylic acid and / or its ester manufacturing process, a substituted acrylic acid and / or its ester manufacturing process, an acrylate manufacturing process, a vinyl acetate manufacturing process, or a styrene manufacturing process.

[0024] The use of the compositions disclosed herein for reducing scaling during chemical manufacturing processes is also provided.

[0025] The features and technical advantages of this disclosure have been summarized quite broadly above in order to better understand the following detailed description. Further features and advantages of this disclosure that form the subject matter of the claims of this application will be described below. It will be understood by those skilled in the art that the disclosed concepts and specific embodiments can be readily utilized as a basis for modifications or the design of other embodiments in order to perform the same purpose of this disclosure. Those skilled in the art should also recognize that such equivalent embodiments do not depart from the spirit and scope of this disclosure as set forth in the appended claims. Detailed Implementation

[0026] While this disclosure provides reference to preferred embodiments, those skilled in the art will recognize that changes in form and detail may be made without departing from the spirit and scope of this disclosure. Furthermore, any embodiments set forth in this specification are not intended to be limiting and merely illustrate some of the many possible implementations described in the appended claims.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. In case of conflict, this document (including definitions) shall prevail. Methods and materials are described below, but similar or equivalent methods and materials may be used to practice or test the invention. All publications, patent applications, patents, and other references mentioned herein are incorporated herein by reference in their entirety.

[0028] As used herein, the terms “including,” “comprising,” “having,” “possessing,” “may,” “containing,” and their variations are intended to be open-ended transitional phrases, terms, or words that do not preclude the possibility of additional actions or structures. Unless the context explicitly indicates otherwise, the singular forms “a,” “and,” and “the” contain plural referents.

[0029] The transitional phrase “includes”, “contains”, or “characterized in” is inclusive or open-ended and does not exclude additional unreferenced elements, components, ingredients, and / or method steps.

[0030] The transitional phrase "composed of" excludes any element, component, ingredient, and / or method step not specified in the claims.

[0031] The transitional phrase “consistent essentially of…” limits the scope of the claim to the specified elements, components, ingredients and / or steps, as well as those elements, components, ingredients and / or steps that do not substantially affect the essential and novel features of the claimed invention.

[0032] As used herein, the terms “optional” or “optionally” mean that an event or situation described subsequently may but not necessarily occur, and that description includes instances where the event or situation occurs and instances where the event or situation does not occur.

[0033] As used herein, the term "about," used in describing embodiments of this disclosure, refers to variations in numerical quantities that may occur, for example, by typical measurement and processing procedures used to prepare compounds, compositions, concentrates, or formulations; by negligent errors in these procedures; by differences in the manufacture, origin, or purity of starting materials or ingredients used in the methods; and by similarly close considerations. The term "about" also covers amounts that differ from a particular starting concentration or mixture due to aging of the formulation, and amounts that differ from a particular starting concentration or mixture due to mixing or processing of the formulation. In cases modified by the term "about," the appended claims contain equivalents of these amounts. The term "about" means that the referenced value is within the error caused by the standard deviation found in their respective test measurements, and if those errors are undetermined, then "about" may refer to, for example, less than 5% of the referenced value.

[0034] Additionally, unless the context specifically restricts it, "about" is used to describe a range of values, such as "about 1 to 5" which means "1 to 5" and "about 1 to about 5" and "1 to about 5" and "about 1 to 5".

[0035] A solution “substantially free” of a specified compound or material may be free of the compound or material, or may be present in trace amounts as a result of undesirable contamination, side reactions, incomplete purification, or the test method used. “Trace amounts” can be a trace quantity, an unmeasurable quantity, an amount that does not interfere with a value or characteristic, or some other quantity as provided in the context. A composition having components from the list provided “substantially only” may consist of only those components, or have trace amounts of some other components present, or have one or more additional components that do not substantially affect the properties of the composition. Furthermore, the modification of “substantially” as used, for example, in describing embodiments of this disclosure, of the type or amount, nature, measurable amount, method, value, or range of an ingredient in a composition, means a variation that does not affect all of the composition, nature, amount, method, value, or range in a manner that invalidates the intended composition, nature, amount, method, value, or range. The appended claims modified by the term “substantially” include equivalents according to this definition.

[0036] As used herein, any range of values ​​encompasses all values ​​within that range and should be interpreted as supporting any subrange of claims having endpoints of real values ​​within that range. For example, the ranges 1 through 5 of the disclosure in this specification should be considered to support any of the following ranges: 1-5; 1-4; 1-3; 1-2; 2-5; 2-4; 2-3; 3-5; 3-4; and 4-5.

[0037] Unless otherwise specified, all molecular weights referred to herein are weight-average molecular weights, and all viscosities are measured at 25°C with pure (undiluted) polymers.

[0038] In some embodiments, methods to ensure that dispersants used in industrial processes do not solidify at or near 0°C include the use of antifreeze dispersant compositions. In some embodiments, the industrial processes in question may be in the production and transportation of oils, cement, rubber, pesticides, insecticides, textiles, and / or printed materials.

[0039] This document describes compositions and methods for keeping dispersants suspended and preventing them from solidifying at low temperatures. The antifreeze dispersant compositions may include dispersants and solvents.

[0040] Unpurified dispersants are dispersants produced prior to any purification process. Unless otherwise stated, unpurified dispersants are produced through one or more chemical processes involving one or more chemical reactants. Purified dispersants are obtained after undergoing one or more purification steps.

[0041] The dispersant may be a sulfonated compound. Antifreeze sulfonated dispersants may include a mixture of sulfonated compounds and solvents. Antifreeze sulfonated dispersants do not solidify or form precipitates in the composition at low temperatures ranging from about 0°C to about -25°C.

[0042] In some embodiments, the sulfonated compound is sulfonated oil, sulfonated fatty acid, sulfated oil, sulfated fatty acid, naphthalenesulfonate formaldehyde condensate, styrene sulfonate polymer and its related salts, as well as mixtures and combinations thereof. Examples of sulfonated compounds include, but are not limited to, naphthalenesulfonate formaldehyde condensate and styrene sulfonate polymer.

[0043] In some embodiments, the sulfonating compound may be in the form of a sulfonate or a salt thereof. In some embodiments, the sulfonating dispersant is present in the composition at a weight percentage ranging from about 1 wt.% to about 80 wt.%. In some embodiments, the sulfonating dispersant is present in the composition at a weight percentage of about 1 wt.% to about 60 wt.%. In some embodiments, the sulfonating dispersant is present in the composition at a weight percentage of about 5 wt.% to about 60 wt.%. In some embodiments, the sulfonating dispersant is present in the composition at a weight percentage of about 10 wt.% to about 50 wt.%. In some embodiments, the sulfonating dispersant is present in the composition at a weight percentage of about 15 wt.% to about 50 wt.%. In some embodiments, the sulfonating dispersant is present in the composition at a weight percentage of about 10 wt.%, about 15 wt.%, about 20 wt.%, about 30 wt.%, about 40 wt.%, about 50 wt.%, about 60 wt.%, or about 70 wt.%.

[0044] In some embodiments, the sulfonated compounds applicable herein have a general structure:

[0045] R-(SO3) n M

[0046] Where R is a hydrocarbon group selected from straight-chain or branched alkyl, aromatic, cycloalkyl, aryl or alkenyl groups.

[0047] As used herein, “alkyl” or “alkenyl” can have 1 to about 29 carbon atoms; it is partially or completely oxidized. The term “cycloalkyl” itself, or as part of another substituent, refers to a cyclic alkyl group having a specified number of carbon atoms and is a subset of the term “alkyl”. Other subsets of the term “alkyl” include “straight-chain” and “branched” alkyl groups, which refer to two different types of acyclic alkyl groups. Examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, isobutyl, sec-butyl, cyclohexyl, cyclopentyl, (cyclohexyl)methyl, cyclopropylmethyl, bicyclo[2.2.1]heptane, bicyclo[2.2.2]octane, etc. In this list of examples, examples of methyl, ethyl, n-propyl, and n-butyl alkyl are also examples of “straight-chain alkyl” groups. Similarly, isopropyl and tert-butyl are examples of “branched alkyl” groups. Cyclopentyl, cyclohexyl, (cyclohexyl)methyl, cyclopropylmethyl, bicyclo[2.2.1]heptane, and bicyclo[2.2.2]octane are examples of "cycloalkyl" groups.

[0048] "Aromatic group" refers to a polyunsaturated aromatic hydrocarbon group having a single ring (monocyclic) or multiple rings (bicyclic), which can be fused together or covalently linked. Aromatic groups having 6-10 carbon atoms are suitable, wherein this number of carbon atoms can, for example, be determined by C... 6-10 This indicates that aryl groups include phenyl and naphth-1-yl, naphth-2-yl, biphenyl, etc. Unless otherwise stated, aryl groups can be substituted or unsubstituted. A substituted aryl group can be substituted by one or more substituents. Suitable substituents for aryl groups include substituted or unsubstituted C-terminal groups. 1-8 Alkyl groups and those substituents discussed above regarding substituted alkyl groups.

[0049] The “M” group can be H, alkali metal, alkaline earth metal, alkali metal cation, alkaline earth metal cation, ammonium cation, or alkylammonium cation, and “n” ranges from 1 to about 10. In some aspects, n is 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10.

[0050] In some respects, sulfonated dispersants are compounds of formula I.

[0051] Formula I (CAS No. 36290-04-7)

[0052] The compounds of Formula I can be in the form of potassium salt (CAS No. 67828-14-22) or ammonium salt (CAS No. 9069-80-1).

[0053] In some embodiments, the sulfonated compound is a naphthalenesulfonic acid / formaldehyde condensation product (e.g., a compound of formula I) or a mixture of different salts thereof. For example, in some embodiments, a mixture of sodium naphthalenesulfonic acid / formaldehyde and potassium naphthalenesulfonic acid / formaldehyde is used as a dispersant.

[0054] Sulfonated compounds can be prepared using any method known to those skilled in the art. For example, sulfonated oils, sulfonated fatty acids, sulfated oils, sulfated fatty acids, naphthalenesulfonate formaldehyde, sulfonic acids, dodecylbenzenesulfonic acid, and metal salts of lignin sulfonate, as well as sulfonate polymers, are described in U.S. Patent Nos. 5,650,072, 5,746,924, and 8,067,629, the entire contents of which are incorporated herein by reference.

[0055] These sulfonated dispersants are mixed and / or dissolved in a solvent to form an antifreeze composition. Examples of solvents include, but are not limited to, water, hydroxyl-functionalized compounds, and mixtures thereof. In some respects, the solvent is an alcohol. In other respects, the solvent is a diol selected from ethylene glycol, glycerol, glycol ethers, and any combination thereof.

[0056] The amount of alcohol in the solvent can range from about 1 wt.% to about 99 wt.%. In some aspects, the amount of alcohol in the solvent ranges from about 5 wt.% to about 30 wt.%. In some aspects, the amount of alcohol in the solvent is about 5 wt.%, about 7 wt.%, about 9 wt.%, about 10 wt.%, about 12 wt.%, about 14 wt.%, about 16 wt.%, about 18 wt.%, about 20 wt.%, about 22 wt.%, about 24 wt.%, about 26 wt.%, about 28 wt.%, or about 30 wt.%.

[0057] In some embodiments, the alcohol, glycol ether, and / or mixture may comprise about 15 wt.% to about 25 wt.% of the antifreeze dispersant composition. In some embodiments, the alcohol, glycol ether, and / or mixture may comprise about 32 wt.% to about 42 wt.% of the antifreeze dispersant composition.

[0058] In some embodiments, the solvent includes, but is not limited to, water and alcohol. Alcohol can dissolve sulfonated compounds at low temperatures without leaving any precipitate.

[0059] In some embodiments, ethylene glycol is a preferred alcohol.

[0060] In some embodiments, the solvent may include ethylene glycol. Ethylene glycol may comprise about 20 wt.% to about 80 wt.% of the solvent mixture.

[0061] In some embodiments, ethylene glycol may comprise about 15 wt.% to about 25 wt.% of the antifreeze dispersant composition. In some embodiments, ethylene glycol comprises about 32 wt.% to about 42 wt.% of the antifreeze dispersant composition.

[0062] In some embodiments, the sulfonated dispersant may comprise about 15 wt.% to about 35 wt.% of the antifreeze dispersant composition. In some embodiments, the sulfonated dispersant may comprise about 55 wt.% to about 85 wt.% of the antifreeze dispersant composition.

[0063] In some embodiments, the sulfonated dispersant may comprise about 25 wt.% to about 35 wt.% of the antifreeze dispersant composition. In some embodiments, the sulfonated dispersant may comprise about 15 wt.% to about 25 wt.% of the antifreeze dispersant composition.

[0064] In some embodiments, the antifreeze dispersant composition may include about 31.5 wt.% of a sulfonated dispersant and about 19 wt.% of an alcohol.

[0065] In some embodiments, the antifreeze dispersant composition may consist of about 31.5 wt.% of a sulfonated dispersant, about 49.5 wt.% of water, and about 19 wt.% of an alcohol. The composition will not solidify at a temperature of about -15°C.

[0066] In some embodiments, the antifreeze dispersant composition may include about 18 wt.% of a sulfonated dispersant and about 37 wt.% of an alcohol.

[0067] In some embodiments, the antifreeze dispersant composition may consist of about 18 wt.% of a sulfonated dispersant, about 45 wt.% of water, and about 37 wt.% of an alcohol. The composition will not solidify at a temperature of about -25°C.

[0068] In some embodiments, the compound of Formula I may comprise about 15 wt.% to about 35 wt.% of the antifreeze dispersant composition. In some embodiments, the compound of Formula I may comprise about 55 wt.% to about 85 wt.% of the antifreeze dispersant composition.

[0069] In some embodiments, the ratio of ethylene glycol to water in the antifreeze dispersant composition is in the range of 0 to 5.0.

[0070] Antifreeze dispersant compositions can be prepared using any method known to those skilled in the art. In some embodiments, the antifreeze dispersant composition can be produced by a manufacturing process comprising: production of a sulfonated dispersant, purification of the sulfonated dispersant, drying of the pure sulfonated dispersant, and dissolution of the sulfonated dispersant in a solvent.

[0071] In some implementations, sulfonated dispersants can be produced using a sulfuric acid sulfonation process.

[0072] In some implementations, sulfonated dispersants can be produced using a formaldehyde condensation process.

[0073] In some embodiments, sulfonated dispersants can be produced by neutralizing with an alkali solution or a mixture of alkali solutions and drying into a powder.

[0074] In some embodiments, during the neutralization subprocess, an alkaline mixture of potassium hydroxide and sodium hydroxide is added to adjust the pH to a range of about 5 to about 11. In some embodiments, the pH range is about 6 to about 9. The molar ratio of potassium hydroxide to sodium hydroxide is in the range of 100:1 to 1:100, for example, 3:1 to 10:1.

[0075] In some embodiments, the crude sulfonated dispersant may be a mixture of sulfonates formed by any of the aforementioned methods.

[0076] In some embodiments, the crude sulfonated dispersant can be purified by adding a poor solvent such as sulfate (e.g., methanol) to the dispersant solution and mixing the mixture to form a precipitate. Other poor solvents include, but are not limited to, ethanol, propanol, and isopropanol.

[0077] In some implementations, the sulfate content in the dispersant can be reduced by adding calcium hydroxide or calcium oxide to form calcium sulfate. However, residual calcium ions can have negative effects in subsequent applications (e.g., scaling).

[0078] In some embodiments, methanol is used as a poor solvent. It can reduce the amount of inorganic impurities in the dispersant to about 5 wt.% or less. In some embodiments, the amount of methanol in the solvent can range from about 10 wt.% to about 90 wt.%, for example, from about 20 wt.% to about 50 wt.%.

[0079] In some embodiments, after separating the formed precipitate, the solution is dried to form a purified dispersant. In some embodiments, aqueous methanol can be recycled for use in the purification process.

[0080] In some embodiments, the purified dispersant is dissolved in a solvent mixture of water and polyol and mixed to the desired concentration.

[0081] In another embodiment, the antifreeze sulfonated dispersant can be produced by a different manufacturing process than described above.

[0082] The antifreeze dispersant compositions disclosed herein can be added to industrial processes to reduce fouling. The compositions can be added to chemical manufacturing processes, such as those involving acrolein, acrylic acid and / or its esters, substituted acrylic acid and / or its esters, acrylonitrile, vinyl acetate, styrene, etc. The dispersant can help remove fouling from systems and extend operating length.

[0083] The antifreeze dispersant composition can be injected via pump or flow meter at any location in the process where scaling or potential fouling occurs. Examples of locations where scaling or potential fouling occurs include, but are not limited to, recovery towers, quaternary evaporators, purification towers, or reboilers. The amount of composition added to the process can range from about 1 ppm to about 1000 ppm.

[0084] Example

[0085] Experiments were conducted to determine the parameter ranges that provide suitable antifreeze dispersant compositions. The freezing points of different compositions prepared with different wt.% sulfonated dispersants (e.g., compounds of Formula I) and different wt.% solvents (e.g., ethylene glycol) were determined. The freezing points of those compositions were determined after multiple freeze-thaw cycles. In some embodiments, they were determined after at least three freeze-thaw cycles.

[0086] The ideal antifreeze dispersant composition is determined after ensuring that the composition has a freezing point less than or equal to about -18°C, and that the composition can survive at its freezing point without any change after at least three freeze-thaw cycles at about -18°C. A composition is considered "surviving" if it can be restored to a liquid state at temperatures above its freezing point without deposits. It can then be refrozen when the temperature reaches its freezing point.

[0087] In one embodiment, the antifreeze dispersant composition may include about 31.5 wt.% of the purified composition of Formula I, about 49.5 wt.% of water, and about 19 wt.% of ethylene glycol. The composition does not solidify at a temperature of about -15°C.

[0088] In one embodiment, the antifreeze dispersant composition may include about 9 wt.% of the purified composition of Formula I, about 45.5 wt.% of water, and about 45.5 wt.% of ethylene glycol. The composition does not solidify at a temperature of about -25°C.

[0089] The sulfonate is produced by reacting naphthalene with sulfuric acid at about 120°C to form naphthalenesulfonic acid, followed by hydrolysis. Then, about 37 wt.% formaldehyde is added. Neutralization is achieved by adding an alkaline mixture of NaOH and KOH (K / Na molar ratio of about 3:1), and the pH is adjusted to about 7 to about 9. The reaction product is then dried and added to water to form a solution.

[0090] Approximately 10 wt.% methanol was added to the aqueous solution of the reaction product to promote the formation of the sulfate precipitate. The precipitate was filtered and dried to obtain a purified dispersant. The sulfate content in the solid was approximately 15 wt.% as calculated by Na₂SO₄.

[0091] The purified dispersant was dissolved in approximately 72.3 wt.% water and approximately 27.7 wt.% ethylene glycol to produce a solution of approximately 31.5 wt.% by mixing. The resulting dispersant solution did not solidify at approximately -15°C and no precipitate formed in the solution within approximately one month.

[0092] In another embodiment, the sulfonate compound is prepared by reacting naphthalene with about 98 wt.% sulfuric acid at about 120°C to form naphthalenesulfonic acid, followed by hydrolysis. Then, about 37 wt.% formaldehyde is added, followed by the addition of an alkaline mixture of NaOH and KOH (K / Na molar ratio of 7:1) for neutralization. The pH is adjusted to about 7 to about 9. The product is filtered and dried to form a dispersant powder. This powder is dissolved in a 45 wt.% aqueous solution.

[0093] Approximately 15 wt.% methanol was added to the aqueous solution to promote the formation of the sulfate precipitate. The precipitate was filtered, and the remaining solution was dried to obtain a purified solid dispersant. The sulfate content in the Na₂SO₄ solid was calculated to be approximately 18 wt.%.

[0094] The purified dispersant was dissolved in approximately 72.3 wt.% water and approximately 27.7 wt.% ethylene glycol to produce a solution of approximately 31.5 wt.%. The resulting dispersant solution did not solidify at approximately -10°C and no precipitate formed in the solution within approximately one month.

[0095] In another example, the sulfonated compound is prepared by reacting naphthalene with about 98 wt.% sulfuric acid at about 120°C to form naphthalenesulfonic acid, followed by hydrolysis. Then, about 37 wt.% formaldehyde is added, followed by the addition of an alkaline mixture of NaOH and KOH (K / Na molar ratio of 7:1) for neutralization. The pH is adjusted to about 7 to about 9. The product is filtered and dried to form a dispersant powder. This powder is dissolved in about 45 wt.% of an aqueous solution.

[0096] Approximately 15 wt.% methanol was added to the aqueous solution to promote the formation of the sulfate precipitate. The precipitate was filtered, and the remaining solution was dried to obtain a purified solid dispersant. The sulfate content in the Na₂SO₄ solid was calculated to be approximately 18 wt.%.

[0097] The purified dispersant was dissolved in approximately 78.1 wt.% water and 21.9 wt.% ethylene glycol to produce a solution of approximately 31.5 wt.%. The resulting dispersant solution did not solidify at approximately -12°C and no precipitate formed in the solution within approximately one month.

[0098] In another embodiment, the sulfonate compound is prepared by reacting naphthalene with about 98 wt.% sulfuric acid at about 120°C to form naphthalenesulfonic acid, followed by hydrolysis. Then, about 37 wt.% formaldehyde is added, followed by the addition of an alkaline mixture of NaOH and KOH (K / Na molar ratio of 7:1) for neutralization. The pH is adjusted to about 7 to about 9. The product is filtered and dried to form a dispersant powder. This powder is dissolved in about 45 wt.% of an aqueous solution.

[0099] Approximately 15 wt.% methanol was added to the aqueous solution to promote the formation of the sulfate precipitate. The precipitate was filtered, and the remaining solution was dried to obtain a purified solid dispersant. The sulfate content in the Na₂SO₄ solid was calculated to be approximately 18 wt.%.

[0100] The purified dispersant was dissolved in approximately 50 wt.% water and 50 wt.% ethylene glycol to produce a solution of approximately 9 wt.%. The resulting dispersant solution did not solidify at approximately -25°C and no precipitate formed in the solution within approximately one month.

[0101] All compositions and methods disclosed and claimed herein can be prepared and performed according to this disclosure without excessive experimentation. While the invention may be embodied in many different forms, specific preferred embodiments of the invention are described in detail herein. This disclosure is exemplary of the principles of the invention and is not intended to limit the invention to the specific embodiments illustrated. Furthermore, unless expressly stated to the contrary, the term "a" is intended to include "at least one" or "one or more". For example, "a solvent" is intended to include "at least one solvent" or "one or more solvents".

[0102] Furthermore, this invention covers any and all possible combinations of some or all of the various embodiments described herein. It should also be understood that various changes and modifications to the currently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the invention and without diminishing its intended advantages. Therefore, the appended claims are intended to cover such changes and modifications.

Claims

1. A composition comprising: Sulfonated dispersant, wherein the sulfonated dispersant is a naphthalenesulfonic acid formaldehyde condensate; and solvent, Wherein, the freezing point of the composition is below 0. o C, and The composition comprises 5 wt.% to 20 wt.% of the sulfonated dispersant and the solvent comprises 40 wt.% to 60 wt.% of ethylene glycol and 20 wt.% to 55 wt.% of water; or the composition comprises 25 wt.% to 45 wt.% of the sulfonated dispersant and the solvent comprises 10 wt.% to 30 wt.% of ethylene glycol and 25 wt.% to 65 wt.% of water.

2. The composition according to claim 1, wherein, The naphthalenesulfonic acid formaldehyde condensate is a polymer of 2-naphthalenesulfonic acid and formaldehyde or a salt thereof.

3. The composition according to claim 2, wherein, The salt of the polymer of 2-naphthalenesulfonic acid and formaldehyde is a sodium salt, potassium salt, ammonium salt, or a mixture thereof.

4. A method for preparing the composition according to any one of claims 1 to 3, comprising: The sulfonated dispersant is dissolved in a solvent.

5. A method for preparing the composition according to any one of claims 1 to 3, comprising: Naphthalene sulfonate reacts with formaldehyde to form a sulfonated dispersant; The sulfonated dispersant was purified by adding a solvent to form a solution. The precipitate was separated from the solution; Dry the solution to form a powder; and The powder is dissolved in a second solvent.

6. The method according to claim 5, wherein, The solvent is a poor solvent for sulfates.

7. The method according to claim 5 or claim 6, wherein, The solvent is methanol.

8. A method for reducing scaling in industrial processes, comprising: In the industrial process, the composition comprising a sulfonated dispersant and a solvent according to any one of claims 1 to 3 is added to an aqueous medium.

9. The method according to claim 8, wherein, The industrial process in question is a chemical manufacturing process.

10. The method according to claim 9, wherein, The chemical manufacturing process is an acrolein manufacturing process, an acrylic acid and / or its ester manufacturing process, a substituted acrylic acid and / or its ester manufacturing process, an acrylonitrile manufacturing process, a vinyl acetate manufacturing process, or a styrene manufacturing process.

11. Use of the composition according to any one of claims 1 to 3 for reducing scaling during chemical manufacturing processes.