Hydrophobicity removing agent for nonionic surfactant and preparation method and application thereof

Abstract

The application discloses a hydrophobic removing agent for nonionic surfactant and a preparation method and application thereof. The hydrophobic removing agent comprises porous polymer microspheres and sol coated on the surface of the porous polymer microspheres. The active component boric acid in the pore channel of the porous polymer microspheres can be complexed with the entering nonionic surfactant, and cannot be complexed with sulfolane, so that selective adsorption of the two is realized, deep removal of the nonionic surfactant in sulfolane is realized, and the loss rate of sulfolane is low; meanwhile, new impurities can be ensured not to be introduced after the nonionic surfactant in sulfolane is removed. Further, the sol is modified and coated to be hydrophobic, and has a repelling effect on water molecules. When the hydrophobic removing agent is applied to removal of the nonionic surfactant in a sulfoxane amine desulfurization solution, the contact probability of boric acid in the removing agent and water molecules in the desulfurization solution is greatly reduced, and the high organic molecule permeability of the colloid can ensure that nonionic surfactant molecules pass through the colloid to contact the boric acid and are removed.

Description

Technical Field

[0001] This invention relates to the field of functional polymer materials, specifically to a hydrophobic remover of nonionic surfactants, its preparation method, and its application. Background Technology

[0002] Many raw natural gas samples extracted from underground reservoirs contain impurities such as H2S and organic sulfur, and cannot be used directly. They must undergo desulfurization and purification to become usable commercial natural gas. Commercial natural gas has regulations specifying the sulfur content, with the current requirement for total sulfur being ≤20 mg / m³. 3 .

[0003] Organic sulfur removal technology must be used to control the organic sulfur content in the product natural gas to a very low level to achieve a total sulfur content of ≤20 mg / m³. 3 The requirements of the indicators are met. Therefore, the demand for organic sulfur removal technology and organic sulfur removal solutions in the natural gas purification field is rapidly increasing.

[0004] Sulfolane is an excellent solvent for organic sulfur compounds, exhibiting a high removal rate. It is considered the preferred solvent for removing organic sulfur compounds from natural gas. The number of purification plants using sulfolane and sulfolane-based physicochemical desulfurization solutions is rapidly increasing.

[0005] Desulfurization solutions are easily contaminated and deteriorated by residues from upstream mining operations during natural gas purification. Foaming due to contamination of the desulfurization solution is the most common and widespread problem in natural gas purification production, and a major factor restricting stable and increased production. Therefore, amine reactivation technology, which can remove foaming contaminants from desulfurization solutions and restore their performance, is a key technology for ensuring stable production in natural gas purification plants. However, existing amine reactivation technologies, when used with sulfolane and sulfolane-based physicochemical desulfurization solutions, cannot effectively separate the foaming agents. The resulting foaming of the desulfurization solution leads to substandard natural gas quality, unstable operation of the natural gas purification unit, and even production stoppages, seriously affecting normal production. Therefore, the need for foaming agent removal technology from sulfolane is extremely urgent in the natural gas purification field.

[0006] Various surfactants in the residues of natural gas extraction operations are the cause of foaming in desulfurization solutions. For example, nonionic surfactants are present in foam draining, demulsifying, corrosion inhibitors, drilling agents, and oil displacement agents. To solve the problem of foaming in desulfurization solutions, these surfactants must be removed.

[0007] Anionic and cationic surfactants can ionize in aqueous solutions, and their ionization properties differ significantly from those of sulfolane. Furthermore, the interaction between anionic / cationic surfactant molecules and sulfolane molecules weakens upon the addition of water. Therefore, the development of removal agents for anionic / cationic surfactants from sulfolane can find a technological breakthrough by addressing these differences in properties. However, nonionic surfactants possess adsorption characteristics extremely similar to sulfolane molecules, including polarity, magnetism, ionization, and organic / inorganic properties, exhibiting very strong affinity for sulfolane. Sulfolane is a suitable choice for extracting nonionic surfactants, but conversely, separating nonionic surfactants from sulfolane is extremely difficult. Existing adsorption materials lack selectivity for both sulfolane and nonionic surfactants. In the presence of high concentrations of sulfolane (50 times or more the concentration of nonionic surfactants in physicochemical desulfurization solutions), the removal rate of nonionic surfactants is extremely low (<10%), and even distillation methods yield only a low removal rate (<30%). Furthermore, because surfactants at concentrations of a few hundred ppm can cause severe foaming in desulfurization solutions, the required depth of surfactant removal from the desulfurization solution is very high. Separating sulfolane from surfactants is already difficult, and achieving deep removal is even more challenging. Therefore, despite its long-standing use in natural gas purification, the problem of how to revive sulfolane after it becomes contaminated and foams has remained unresolved. The only solution to restore production is replacement with a new solvent. The contaminated solution removed from the unit is treated as waste. A single desulfurization unit typically generates over 400 tons of waste due to contamination. Since sulfolane-based desulfurization solutions contain organic matter at a rate of 70% or higher, and also contain toxic components such as hydrogen sulfide, their disposal as hazardous waste is extremely difficult and costly, placing a significant economic burden and environmental pressure on purification plants.

[0008] Existing purification technologies for modified sulfolane include ion exchange separation, precipitation separation, activated carbon adsorption, and decomposition. 1) Ion exchange separation uses anion exchange resins to purify modified sulfolane, as illustrated in patents US5053137, CN1230545A, CN1644581A, CN1076726C, CN1125063C, CN111111306A, and CN1861594A. The anion exchange resins used are styrene-divinylbenzene polymers containing primary, secondary, or quaternary ammonium groups. Anion exchange resins can only remove ionic substances from the solution. Nonionic surfactants do not ionize in water or sulfolane and therefore cannot be removed by ion exchange resins. 2) Precipitation separation method, such as patent US4820849, involves adding polybasic acids or polybasic anhydrides to sulfolane solvent to form solid precipitates with acidic impurities; alkali adsorption separation method, such as Japanese patents JP7-278316, CN1634917A, and CN106957297A, uses oxides, hydroxides, and carbonates of alkali metals or alkaline earth metals to adsorb acidic impurities in sulfolane. Both of these methods can only remove acidic impurities from sulfolane. Nonionic surfactants are not acidic substances, so neither of these methods can remove nonionic surfactants. 3) Activated carbon adsorption method, as described in Japanese patent JP7-101953, uses activated carbon and microfibrous natural cellulose to remove suspended microparticles and dissolve ionic impurities. Activated carbon exhibits no selectivity for the adsorption of sulfolane and nonionic surfactants, with a selectivity ratio <2. In sulfolane desulfurization solutions, the concentration of sulfolane is much higher than that of nonionic surfactants. Due to this concentration advantage, sulfolane occupies the activated carbon adsorption surface before nonionic surfactants, causing it to quickly become saturated. This results in a nonionic surfactant removal rate of less than 10%. 4) Decomposition method: CN213885678U decomposes some of the acidic substances in sulfolane by adding monoethanolamine. Nonionic surfactants cannot be decomposed by monoethanolamine, so this method is also not applicable.

[0009] Existing purification technologies for desulfurization solutions include: ion exchange, electrodialysis, vacuum distillation, activated carbon adsorption separation, and foaming impurity removal technology. Among these technologies, ion exchange and electrodialysis can only remove salt impurities from the desulfurization solution, such as those listed in US6517700, US5162084, US5788864, CN1733355A, CN1230545A, and CN102189008A. Vacuum distillation suffers from high sulfolane loss and low removal rate of nonionic surfactants. Activated carbon adsorption separation and the foaming impurity removal technology independently developed by the Southwest Oil & Gas Field Company have a non-selective adsorption rate for sulfolane and nonionic surfactants, resulting in a nonionic surfactant removal rate of less than 10%.

[0010] Currently, the main methods for treating nonionic surfactant wastewater include foam separation, adsorption, biological methods, micro-electrolysis, and Fenton oxidation. Foam separation is a commonly used physical method that removes nonionic surfactants from foam by bubbling. This method is simple to operate and effectively separates nonionic surfactants. However, for heavily foamed sulfolane desulfurization solutions, the entire solution foams after bubbling, and even after foam separation, 80-90% of the sulfolane is lost. For example, patent CN107935236A uses adsorbent material particles to adsorb surfactants in wastewater, and then bubbling allows the adsorbent material particles to accumulate on the wastewater surface before removal. The adsorbent particles include silica, calcium carbonate, calcium sulfate, activated carbon particles, magnetite powder, hematite powder, titanium dioxide, clay minerals, fly ash or phosphate rock tailings powder, as well as nanoparticles of iron tetroxide, silica, titanium dioxide, and zinc oxide metal oxides synthesized through wet chemical processes; silica and titanium dioxide with amino or carboxyl groups modified on their surfaces; and polystyrene resin particles, phenolic resin particles, or melamine resin particles, including unmodified polystyrene resin particles, unmodified phenolic resin particles, or unmodified melamine resin particles. These adsorbents lack selectivity for sulfolane and nonionic surfactants, exhibiting not only low removal rates of nonionic surfactants from sulfolane but also significant sulfolane loss. The adsorption method, as described in the literature "Research on the Treatment of Nonionic Surfactant Wastewater with Modified Fly Ash," involves modifying fly ash with reagents such as hydrochloric acid and sulfuric acid to prepare a fly ash adsorbent coagulant. This modified fly ash adsorbent coagulant is then used to treat wastewater containing nonionic surfactants such as alkylphenol polyoxyethylene ether. The results show that the modified fly ash exhibits good adsorption performance for wastewater containing alkylphenol polyoxyethylene ether at concentrations of 300–1800 mg / L. However, the modification process requires the addition of hydrochloric acid and sulfuric acid, which can cause secondary pollution by flowing into the wastewater and increasing the difficulty of subsequent wastewater treatment. This method, which causes secondary pollution, is even less suitable for sulfolane. The introduction of hydrochloric acid and sulfuric acid into sulfolane not only causes corrosion but also leads to a decrease in its desulfurization performance or even complete failure, making it unsuitable. The biological method utilizes microorganisms to use nonionic surfactants as a carbon source to degrade them in wastewater. Sulfolane and similar substances are also organic matter and will be degraded simultaneously, making this method unsuitable. Micro-electrolysis is based on electrochemical principles. It involves forming electrode reactions in wastewater to cause nonionic surfactants to undergo catalytic oxidation, coagulation, adsorption, complexation, and displacement reactions, thereby rapidly removing pollutants. Fenton oxidation utilizes ferrous ions in Fenton's reagent as a catalytic initiator. Under its action, H2O2 generates a large number of free radicals, which further accelerates the initiation of free radical chains, thus enabling the rapid degradation and removal of nonionic surfactants in wastewater.These two methods are often used in combination, as described in patents CN110357357A, CN1508077A, CN104310665, and CN109626675A. These methods require first adding acid to adjust the pH to 0.5–5, then introducing ferric and ferrous ions. These methods are unsuitable for sulfolane because adding acid reduces its desulfurization performance or even causes complete failure, increases its corrosiveness, and the precipitation formed when ferric and ferrous ions come into contact with hydrogen sulfide can lead to blockage of the desulfurization equipment.

[0011] In summary, existing technologies have very low removal rates of nonionic surfactants from sulfolane (<30%), lack selectivity in the removal of sulfolane and nonionic surfactants (selectivity ratio <2), have high sulfolane loss rates, and some technologies may introduce new impurities into the solution, leading to poorer desulfurization performance and increased corrosivity. Summary of the Invention

[0012] One object of the present invention is to provide a hydrophobic remover for nonionic surfactants and a method for preparing the same. The hydrophobic remover of the present invention exhibits high selectivity for nonionic surfactants and sulfolane, and can achieve the removal of nonionic surfactants from solutions containing sulfoneamine.

[0013] Another object of the present invention is to provide an application of the hydrophobic remover of the aforementioned nonionic surfactant, particularly in the deep removal of nonionic surfactants in sulfoneamine solutions.

[0014] To achieve the above objectives, the present invention adopts the following technical solution:

[0015] This invention provides a method for preparing a hydrophobic remover of nonionic surfactants, wherein the preparation method includes the following steps:

[0016] A porous polymer microsphere is obtained by suspending and copolymerizing acrylate monomers, aliphatic diene crosslinking agents, and pore-forming agents in water; the porous polymer microspheres are then immersed in a boric acid solution to load boric acid, and then the microspheres are filtered out and dried.

[0017] The hydrophobic remover is obtained by coating the surface of porous polymer microspheres loaded with boric acid with a sol and then aging them.

[0018] The sol is prepared by a sol-gel method using silicate ester and alkoxysilane, wherein the structural formula of the alkoxysilane is as follows: Wherein, R1 is a C1-C10 alkyl group and R2 is a C5-C20 fluoroalkyl group.

[0019] Specifically, the active component boric acid within the porous polymer microspheres can complex with the introduced nonionic surfactant without complexing with sulfolane, thus achieving selective adsorption of both. This results in deep removal of the nonionic surfactant from sulfolane with a low sulfolane loss rate. Simultaneously, it ensures that no new impurities are introduced after the removal of the nonionic surfactant from sulfolane. Further sol-gel modification and coating to make it hydrophobic, repelling water molecules, significantly reduces the contact probability between boric acid and water molecules in the desulfurization solution when applied to the removal of nonionic surfactants in sulfoneamine desulfurization solutions. Furthermore, the high organic molecule permeability of the colloid ensures that nonionic surfactant molecules can pass through the colloid and contact with boric acid for removal.

[0020] In some embodiments of the present invention, preferably, the silicate ester is tetraethyl orthosilicate.

[0021] In some embodiments of the present invention, preferably, in the alkoxysilane, R1 is a C1-C5 alkyl group and R2 is a C9-C17 fluoroalkyl group.

[0022] In some embodiments of the present invention, more preferably, R1 is methyl, ethyl or propyl.

[0023] In some embodiments of the present invention, more preferably, R2 is nonafluorohexyl, tridecafluorooctyl or heptadecafluorodecyl.

[0024] In some embodiments of the present invention, most preferably, R2 is heptadecafluorodecyl.

[0025] In some embodiments of the present invention, preferably, the structural formula of the acrylate monomer is:

[0026]

[0027] Wherein R is a C1 to C5 alkyl group; preferably, the acrylate monomer is methyl acrylate or hexyl acrylate, more preferably hexyl acrylate.

[0028] Sulfolane has a weak affinity for alkanes but a strong affinity for aromatics. Therefore, this invention does not choose styrene, a commonly used monomer, but instead uses acrylate. While the ester groups in acrylate have some adsorption capacity for sulfolane, the alkyl groups exhibit a shielding effect on the adsorption of sulfolane by the ester groups. The more carbon atoms in the alkyl group, the greater the shielding effect. However, an excessively large number of alkyl groups may generate long polyacrylate segments and linear acrylate homopolymers during polymerization, causing the prepared remover to clump together during use. The number of alkyl groups in hexyl acrylate best balances these two issues, satisfying both a sufficiently strong shielding effect for extremely weak sulfolane adsorption and preventing clumping of the remover during use. Therefore, hexyl acrylate is the preferred acrylate monomer in this invention.

[0029] In some embodiments of the present invention, preferably, the aliphatic diene crosslinking agent is ethylene glycol dimethacrylate.

[0030] The polymer stripper of this invention selects an aliphatic diene as the crosslinking agent, rather than the conventional phenyl-containing divinylbenzene, because phenyl groups adsorb sulfolane. Preferred dimethacrylate (ethylene glycol dimethacrylate) increases the swelling degree of the copolymer, resulting in a higher interchain distance in the final polymer, which facilitates the penetration of larger molecular weight nonionic surfactants.

[0031] In some embodiments of the present invention, preferably, the pore-forming agent is selected from at least one of isooctyl alcohol, n-decane, decanol, and 2-ethyl-1-hexanoic acid.

[0032] The micropores prepared using isooctyl alcohol, n-decane, decanol, and 2-ethyl-1-hexanoic acid have a pore size that is suitable for the subsequent introduction of the active component boric acid, without being too large to weaken the potential energy superposition effect of each plane. Other porogens either result in a lower loading of the active component boric acid or weaker adsorption of nonionic surfactants, which may lead to the problem of a small amount of adsorbed nonionic surfactants being desorbed.

[0033] In some embodiments of the present invention, preferably, the molar ratio of the acrylate monomer, the aliphatic diene crosslinking agent, and the porogen is 1:(0.07-0.3):(0.1-0.8).

[0034] When the crosslinking agent dosage is higher than 0.3%, the internal structure of the resulting porous polymer microspheres will be too dense, increasing the shuttle resistance of nonionic surfactant molecules within the microspheres. This is detrimental to both adsorption and desorption during regeneration, resulting in a low removal rate. When the crosslinking agent dosage is lower than 0.07%, the resulting porous polymer microspheres will aggregate in sulfolane desulfurization solution. When the porogen dosage is lower than 0.1%, the pore capacity and specific surface area of ​​the resulting porous polymer microspheres are too low, with an adsorption capacity <10 mg / g, which does not meet the usage requirements. When the porogen dosage is higher than 0.8%, the porous polymer microspheres will exhibit poor strength and internal pore structure collapse.

[0035] In some embodiments of the present invention, more preferably, the molar ratio of the acrylate monomer, the aliphatic diene crosslinking agent, and the porogen is 1:(0.1-0.2):(0.5-0.6).

[0036] In some embodiments of the present invention, preferably, the porous polymer microspheres loaded with boric acid have a particle size distribution of 0.2 mm to 1.0 mm and a specific surface area of ​​300 m². 2 / g~400m 2 / g, wherein the average pore size of the porous polymer microspheres is 50nm to 110nm, and the pore volume is 1.5mL / g to 2.0mL / g.

[0037] In some embodiments of the present invention, preferably, the sol is prepared by the following steps:

[0038] The silicate ester was mixed with ethanol, then added to acidic water and mixed again. Alkoxysilane was then added and the mixture was continued for 8 to 12 hours. After standing for 20 to 40 hours, the sol was obtained.

[0039] Silicate esters and alkoxysilanes polymerize in water after hydrolysis to form a sol. Ethanol is added to make silicates and alkoxysilanes miscible with water. Adding acid to adjust the acidity of the water controls the gelation rate, resulting in a sol with a uniform particle size distribution. The molecular structure and size of alkoxysilanes are crucial in determining the pore size of the resulting colloid; colloids made with defined alkoxysilanes have pore sizes suitable for nonionic surfactant molecules.

[0040] In some embodiments of the present invention, preferably, the molar ratio of the silicate ester to ethanol is 1:(3-8).

[0041] Excessive ethanol content not only slows down the gelation process but also results in excessively small particle sizes. Hydrophobic removers made from such sols have low surface permeability, hindering the contact between nonionic surfactant molecules and boric acid. Conversely, insufficient ethanol content prevents the silicate ester, alkoxysilane, and water from becoming miscible. Therefore, the preferred molar ratio of silicate ester to ethanol in this invention is 1:(3-8).

[0042] In some embodiments of the present invention, preferably, the acidic water is adjusted to pH 1 to 6 by adding acid dropwise to the water, more preferably 2 to 3.

[0043] Under alkaline conditions, hydrolysis is too rapid, and the sol easily coagulates into lumps. If the acidity is too strong, the gelation is too slow, which also results in uneven particle size. Only 48% of the particles have the required particle size of 2nm to 3nm. When the pH value is 2 to 3, a sol with uniform particle size can be formed, and the proportion of particles with a particle size of 2nm to 3nm reaches more than 80%.

[0044] In some embodiments of the present invention, preferably, the molar ratio of the silicate ester to water is 1:(0.5 to 1.1).

[0045] Excessive water usage (a molar ratio of water to silicate ester greater than 1.2) not only results in slow gelation but also leads to excessively low viscosity of the formed sol. Hydrophobic removers made from such sols experience coating peeling during use. Insufficient water usage results in unevenly distributed colloidal particles. Therefore, the preferred molar ratio of silicate ester to water in this invention is 1:(0.5–1.1).

[0046] In some embodiments of the present invention, preferably, the molar ratio of the silicate ester to alkoxysilane is 1:(0.6 to 1.5).

[0047] When the molar ratio of alkoxysilane to silicate is less than 0.6, the resulting colloid is not hydrophobic enough; when it is greater than 1.5, the colloid will not meet the requirements for hydrophobicity due to the excessively large pores formed.

[0048] The preparation process of the porous polymer microspheres includes: suspending and copolymerizing acrylate monomers, aliphatic diene crosslinking agents and porogens in water to obtain porous polymer microspheres; immersing the porous polymer microspheres in a boric acid solution to load boric acid; and then filtering and drying the microspheres.

[0049] In some embodiments of the present invention, preferably, the boric acid solution is a saturated boric acid solution at 80-90°C.

[0050] High-concentration boric acid solutions are beneficial for boric acid loading, but boric acid has very low solubility in cold water. Increasing the temperature can increase its solubility; however, the solution tends to boil above 90°C, which is not conducive to the deposition of boric acid on microspheres. Therefore, the present invention preferably uses a saturated boric acid solution at 80–90°C.

[0051] In some embodiments of the present invention, preferably, the mass ratio of boric acid to porous polymer microspheres is >0.1. Too little boric acid will result in the adsorption capacity of the resulting remover for nonionic surfactants being <10 mg / g, which does not meet the usage requirements.

[0052] In some embodiments of the present invention, more preferably, the mass ratio of boric acid to porous polymer microspheres is 0.7:1.

[0053] In some embodiments of the present invention, preferably, the soaking time is >0.5h.

[0054] In some embodiments of the present invention, more preferably, the soaking time is 5h to 6h.

[0055] When the soaking time is less than 0.5 h, the adsorption capacity of the resulting remover for nonionic surfactants is <10 mg / g, which does not meet the usage requirements. After the soaking time exceeds 6 h, the adsorption capacity of the remover no longer increases.

[0056] In some embodiments of the present invention, preferably, the soaking temperature is 50-90°C. At this temperature, the solubility of boric acid is high. Above 90°C, the solution tends to boil, which is not conducive to the deposition of boric acid on the microspheres.

[0057] In some embodiments of the present invention, preferably, the drying temperature is 100–165°C.

[0058] In some embodiments of the present invention, more preferably, the drying temperature is 120–140°C.

[0059] When the drying temperature is above 165℃, boric acid tends to decompose into metaboric acid. A temperature of 120-140℃ can ensure drying without decomposing boric acid, and the drying time is short.

[0060] In some embodiments of the present invention, preferably, the specific process of the sol-gel coating includes:

[0061] The porous polymer microspheres are arranged in a single layer in a container filled with sol. The height of the sol in the container is 1 / 4 to 1 / 3 of the height of the remover particles. The porous polymer microspheres are rolled in the sol until the entire surface is covered with sol. The porous polymer microspheres are then removed.

[0062] Excessive sol coating is detrimental; otherwise, a thicker colloid layer on the surface of the remover will severely reduce the adsorption rate of nonionic surfactants, resulting in insufficient removal. The colloid covering the microsphere surface should be as thin as possible to improve the adsorption rate and removal rate of nonionic surfactants, while ensuring complete colloid coverage of the microsphere surface. The remover prepared using the above coating method can achieve a maximum flow rate of 8 BV / h when reactivating sulfoneamine solution.

[0063] In some embodiments of the present invention, preferably, the aging time is ≥7 days. Less than 7 days results in insufficient adhesion and stability of the colloid on the surface of the remover, manifesting as colloid shedding or fluctuating removal rates.

[0064] Another aspect of the present invention provides a hydrophobic remover for nonionic surfactants, which is obtained by any of the above preparation methods.

[0065] The hydrophobic removal agent includes porous polymer microspheres and a sol coated on the surface of the porous polymer microspheres; the porous polymer microspheres are loaded with boric acid in their pores; the porous polymer microspheres are prepared by suspension copolymerization of acrylate monomers and aliphatic diene crosslinking agents, and the pores are formed by adding a porogen during the polymerization process.

[0066] In another aspect, the present invention provides the application of the above-mentioned hydrophobic removal agents in the removal of nonionic surfactants in organic solutions.

[0067] In some embodiments of the present invention, preferably, the removing agent is used for the removal of nonionic surfactants from sulfolane.

[0068] In some embodiments of the present invention, more preferably, the removing agent is applied to the removal of nonionic surfactants from sulfoneamine solutions.

[0069] In some embodiments of the present invention, preferably, the removing agent is applied in the removal of nonionic surfactants from a sulfonamine solution to provide a method for removing nonionic surfactants from a sulfonamine solution, the method comprising:

[0070] The sulfoneamine solution is first separated by electrodialysis to remove part of the alcohol amine, and the remaining solution is separated by the hydrophobic removal agent to remove the nonionic surfactant;

[0071] The solution from which nonionic surfactants have been removed is mixed with the alcoholic amines separated by electrodialysis to obtain a sulfoneamine solution from which nonionic surfactants have been removed.

[0072] In some embodiments of the present invention, preferably, the percentage of alkanolamines separated by electrodialysis is ≥80%.

[0073] Alkylamines are weakly basic, and their effect on the ionization of boric acid (the active component of nonionic surfactants that complex and adsorbs it) in water increases with increasing concentration and decreases with decreasing concentration. When the concentration of alkylamines in the desulfurization solution is reduced to below 10%, their promoting effect on the ionization of boric acid becomes relatively small. To reduce the concentration of alkylamines in the desulfurization solution to below 10%, 78% or more of the alkylamines need to be separated.

[0074] In some embodiments of the present invention, preferably, when separating alcoholic amines by electrodialysis, sulfonic acid cation exchange membranes and quaternary ammonium anion exchange membranes are used.

[0075] Electrodialysis is more effective at separating substances with stronger ionization capabilities. Alkylamines are weak electrolytes. The quaternary ammonium groups of the quaternary ammonium anion exchange membrane have strong electron-withdrawing properties, while the sulfonic acid groups of the sulfonic acid cation exchange membrane have strong electron-donating properties. These properties can generate a strong "attraction" on the anions and cations ionized from alkylamines, thereby promoting their ionization and achieving a removal rate of over 85%.

[0076] In some embodiments of the present invention, nonionic surfactants in organic solutions are preferably removed by immersion or rinsing.

[0077] In some embodiments of the present invention, more preferably, nonionic surfactants in the organic solution are removed by rinsing. Compared with soaking, rinsing can create a larger concentration gradient, i.e., the difference between the concentration of nonionic surfactants in the solution and the concentration of nonionic surfactants on the removing agent, thus resulting in a higher removal rate.

[0078] In some embodiments of the present invention, preferably, the operating parameters for removing nonionic surfactants from sulfonamide solution by rinsing include: ambient temperature and pressure, and a flow rate of <9 BV / h for rinsing the hydrophobic desiccant with sulfonamide solution.

[0079] In some embodiments of the present invention, more preferably, the flow rate of the sulfonamide solution rinsing the hydrophobic desiccant is 2 BV / h to 3 BV / h.

[0080] The volume of resin loaded in a resin column is called the bed volume (BV). If the flow rate of the solution through the resin column is 2 BV / h to 4 BV / h, the volume of solution passing through per hour is 2 to 4 times the resin bed volume. It takes time for nonionic surfactants in the solution to be adsorbed onto the remover. When using an adsorbent without sol coating, if the flow rate is too high (reaching 20 BV / h or higher), the removal rate is <60%. After the surface of the nonionic surfactant remover is covered with a colloid, the rate at which it adsorbs nonionic surfactants in the desulfurization solution decreases. Therefore, the contact time between the solution and the remover must be increased. If the flow rate reaches 9 BV / h or higher, the removal rate is <60%, and 2 BV / h to 3 BV / h is preferred.

[0081] In some embodiments of the present invention, preferably, after the hydrophobic desiccant is saturated with adsorbed nonionic surfactant, it is regenerated with a weakly polar or moderately polar organic solvent.

[0082] Nonionic surfactant molecules interact more strongly with weakly or moderately polar organic solvent molecules than they interact with boric acid, allowing them to be separated from boric acid and thus desorbed, thereby regenerating hydrophobic desorbents.

[0083] In some embodiments of the present invention, more preferably, the weakly polar or moderately polar organic solvent is dichloromethane and / or ethyl acetate.

[0084] The beneficial effects of this invention include:

[0085] 1) The hydrophobic desorbent of the present invention has high selectivity for the adsorption of nonionic surfactants and sulfolane. The active component boric acid in the porous polymer microspheres can complex with the nonionic surfactants that enter, but will not complex with sulfolane, thereby achieving selective adsorption of both and achieving deep removal of nonionic surfactants from sulfolane with low sulfolane loss rate; at the same time, it can ensure that no new impurities are introduced after the removal of nonionic surfactants from sulfolane.

[0086] 2) When the desorbent of this invention is not sol-coated, it achieves a removal rate of over 98% for nonionic surfactants in sulfolane and exhibits good stability. Even after more than 100 saturated regeneration cycles, its adsorption capacity remains above 98% of its initial capacity. However, when used in sulfoneamine solutions, its adsorption capacity decreases to below 90% of its initial capacity after 39 saturated and regeneration cycles, resulting in poor stability and low economic efficiency. The hydrophobic desorbent obtained after sol-coating modification demonstrates excellent stability and removal rate when applied to sulfoneamine solutions, achieving a removal rate of ≥98% for nonionic surfactants. Furthermore, even after more than 100 saturated regeneration cycles, the hydrophobic desorbent maintains a removal rate above 98% of its initial removal rate, demonstrating excellent economic efficiency and high practical value. Detailed Implementation

[0087] To more clearly illustrate the present invention, the following description, in conjunction with preferred embodiments, further clarifies the invention. Those skilled in the art should understand that the specific descriptions below are illustrative rather than restrictive, and should not be construed as limiting the scope of protection of the present invention.

[0088] The key to this invention lies in the design and preparation of a hydrophobic remover for nonionic surfactants. The hydrophobic remover comprises porous polymer microspheres and a sol coated on the surface of the porous polymer microspheres. Boric acid is loaded within the pores of the porous polymer microspheres. The porous polymer microspheres are prepared by suspension copolymerization of acrylate monomers and aliphatic diene crosslinking agents, with the pores formed during polymerization by adding a pore-forming agent. The sol is prepared from silicate esters and alkoxysilanes via a sol-gel method, wherein the alkoxysilane has the following structural formula: Wherein, R1 is a C1-C10 alkyl group, preferably a C1-C5 alkyl group, more preferably methyl, ethyl, or propyl; R2 is a C5-C20 fluoroalkyl group, preferably a C9-C17 fluoroalkyl group, more preferably nonafluorohexyl, tridecafluorooctyl, or heptadecafluorodecyl, and most preferably heptadecafluorodecyl. The silicate ester is preferably tetraethyl orthosilicate.

[0089] The remover of this invention exhibits high selectivity for nonionic surfactants and sulfolane, enabling the removal of nonionic surfactants from desulfurization solutions containing sulfolane. Specifically, the active component boric acid within the porous polymer microspheres can complex with the introduced nonionic surfactants without complexing with sulfolane, thus achieving selective adsorption of both and deep removal of nonionic surfactants from sulfolane with a low sulfolane loss rate. Simultaneously, it ensures that no new impurities are introduced after the removal of nonionic surfactants from sulfolane. Furthermore, the sol-gel modification coating makes it hydrophobic, repelling water molecules. When applied to the removal of nonionic surfactants from sulfoneamine desulfurization solutions, it significantly reduces the contact probability between boric acid and water molecules in the desulfurization solution. The high organic molecule permeability of the colloid ensures that nonionic surfactant molecules can pass through the colloid and contact with boric acid for removal.

[0090] This invention also specifically utilizes the hydrophobic removal agent to develop a corresponding method for removing nonionic surfactants from sulfonylamine solutions. The method involves designing a process route to reduce the concentration of alkanolamines in the desulfurization solution: first, a portion of the alkanolamines in the sulfonylamine solution is separated using electrodialysis; the remaining solution is then treated with the aforementioned hydrophobic removal agent to remove the nonionic surfactants. The solution from which the nonionic surfactants have been removed is then mixed with the alkanolamines separated by electrodialysis to obtain a sulfonylamine solution free of nonionic surfactants.

[0091] Conventional polymer adsorbents are polymers formed using styrene as a monomer and divinylbenzene as a crosslinking agent. Because sulfolane has a strong affinity for phenyl groups, these adsorbents exhibit strong adsorption of sulfolane. The porous polymer microspheres in the remover of this invention are polymers prepared using acrylate as a monomer and aliphatic dienes as crosslinking agents; neither the monomer nor the crosslinking agent contains phenyl groups.

[0092] Sulfolane has a weak affinity for alkanes but a strong affinity for aromatics. Therefore, this invention does not choose styrene, a commonly used monomer, but instead uses acrylate. While the ester groups in acrylate have some adsorption capacity for sulfolane, the alkyl groups exhibit a shielding effect on the adsorption of sulfolane by the ester groups. The more carbon atoms in the alkyl group, the greater the shielding effect. However, an excessively large number of alkyl groups may generate long polyacrylate segments and linear acrylate homopolymers during polymerization, causing the prepared remover to clump together during use. The number of alkyl groups in hexyl acrylate best balances these two issues, satisfying both a sufficiently strong shielding effect for extremely weak sulfolane adsorption and preventing clumping of the remover during use. Therefore, hexyl acrylate is the most preferred acrylate monomer in this invention.

[0093] The polymer stripper of this invention selects an aliphatic diene as the crosslinking agent, rather than the conventional phenyl-containing divinylbenzene, because phenyl groups adsorb sulfolane. Preferred dimethacrylate (ethylene glycol dimethacrylate) increases the swelling degree of the copolymer, resulting in a higher interchain distance in the final polymer, which facilitates the penetration of larger molecular weight nonionic surfactants.

[0094] The micropores prepared by the preferred porogens n-decane, decyl alcohol, and 2-ethyl-1-hexanoic acid in this invention have a pore size that is suitable for the subsequent introduction of the active component boric acid, without being too large to weaken the potential energy superposition effect of each plane. Other porogens will either result in a lower loading of the active component boric acid or a weaker adsorption of nonionic surfactants, which may lead to the problem of a small amount of adsorbed nonionic surfactants being desorbed.

[0095] In preparing the porous polymer microspheres, the preferred molar ratio of the acrylate monomer, aliphatic diene crosslinking agent, and porogen is 1:(0.07-0.3):(0.1-0.8). When the amount of crosslinking agent is higher than 0.3, the internal structure of the resulting porous polymer microspheres will be too dense, increasing the shuttle resistance of nonionic surfactant molecules within the microspheres, which is detrimental to both adsorption and desorption during regeneration, resulting in a low removal rate. When the amount of crosslinking agent is lower than 0.07, the resulting porous polymer microspheres will aggregate in the sulfolane desulfurization solution. When the amount of porogen is lower than 0.1, the pore capacity and specific surface area of ​​the resulting porous polymer microspheres are too low, with an adsorption capacity <10 mg / g, which does not meet the usage requirements. When the amount of porogen is higher than 0.8, the porous polymer microspheres will exhibit poor strength and internal pore structure collapse. More preferably, the molar ratio of the acrylate monomer, the aliphatic diene crosslinking agent, and the porogen is 1:(0.1-0.2):(0.5-0.6).

[0096] The preferred particle size distribution of the porous polymer microspheres loaded with boric acid in this invention is 0.2 mm to 1.0 mm; the preferred specific surface area is 300 m². 2 / g~400m 2 / g; the average pore size is preferably 50nm~110nm; the pore volume is preferably 1.5mL / g~2.0mL / g.

[0097] The specific method for preparing the hydrophobic removal agent includes the following steps:

[0098] A porous polymer microsphere is obtained by suspending and copolymerizing acrylate monomers, aliphatic diene crosslinking agents, and pore-forming agents in water; the porous polymer microspheres are then immersed in a boric acid solution to load boric acid, and then the microspheres are filtered out and dried.

[0099] The surface of porous polymer microspheres loaded with boric acid is coated with the sol, and then aged to obtain the hydrophobic remover.

[0100] In some specific embodiments, the sol is prepared by the following steps:

[0101] The silicate ester was mixed with ethanol, then added to acidic water and mixed again. Alkoxysilane was then added and the mixture was continued for 8 to 12 hours. After standing for 20 to 40 hours, the sol was obtained.

[0102] Silicate esters and alkoxysilanes polymerize in water after hydrolysis to form a sol. Ethanol is added to make silicates and alkoxysilanes miscible with water. Adding acid to adjust the acidity of the water controls the gelation rate, resulting in a sol with a uniform particle size distribution. The molecular structure and size of alkoxysilanes are crucial in determining the pore size of the resulting colloid; colloids made with defined alkoxysilanes have pore sizes suitable for nonionic surfactant molecules.

[0103] In some specific embodiments, the molar ratio of the silicate ester to ethanol is 1:(3-8). Excessive ethanol not only slows down the gelation process but also results in excessively small particle sizes. Hydrophobic removers made from such sols have low surface permeability, hindering the contact between nonionic surfactant molecules and boric acid. Insufficient ethanol prevents the silicate ester, alkoxysilane, and water from becoming miscible. Therefore, the preferred molar ratio of silicate ester to ethanol in this invention is 1:(3-8).

[0104] In some specific embodiments, the acidic water is adjusted to a pH of 1 to 6, preferably 2 to 3, by adding acid dropwise to the water.

[0105] Under alkaline conditions, hydrolysis is too rapid, and the sol easily coagulates into lumps. If the acidity is too strong, the gelation is too slow, which also results in uneven particle size. Only 48% of the particles have the required particle size of 2nm to 3nm. When the pH value is 2 to 3, a sol with uniform particle size can be formed, and the proportion of particles with a particle size of 2nm to 3nm reaches more than 80%.

[0106] In some specific embodiments, the molar ratio of the silicate ester to water is 1:(0.5 to 1.1).

[0107] Excessive water usage (a molar ratio of water to silicate ester greater than 1.2) not only results in slow gelation but also leads to excessively low viscosity of the formed sol. Hydrophobic removers made from such sols experience coating peeling during use. Insufficient water usage results in unevenly distributed colloidal particles. Therefore, the preferred molar ratio of silicate ester to water in this invention is 1:(0.5–1.1).

[0108] In some specific embodiments, the molar ratio of the silicate ester to alkoxysilane is 1:(0.6 to 1.5).

[0109] When the molar ratio of alkoxysilane to silicate is less than 0.6, the resulting colloid is not hydrophobic enough; when it is greater than 1.5, the colloid will not meet the requirements for hydrophobicity due to the excessively large pores formed.

[0110] In some specific embodiments, the boric acid solution is preferably a saturated boric acid solution at 80–90°C. A high concentration of boric acid solution is beneficial for boric acid loading, but boric acid has very low solubility in cold water; increasing the temperature can increase its solubility. However, at temperatures above 90°C, the solution tends to boil, which is not conducive to the deposition of boric acid on the microspheres. Therefore, the present invention preferably uses a saturated boric acid solution at 80–90°C.

[0111] In some specific embodiments, the mass ratio of boric acid to porous polymer microspheres is >0.1. Too little boric acid will result in the adsorption capacity of the resulting remover for nonionic surfactants being <10 mg / g, which does not meet the usage requirements. More preferably, the mass ratio of boric acid to porous polymer microspheres is 0.7.

[0112] In some specific embodiments, the soaking time is >0.5 h. More preferably, the soaking time is 5 h to 6 h. When the soaking time is less than 0.5 h, the adsorption capacity of the resulting remover for nonionic surfactants is <10 mg / g, which does not meet the usage requirements. After the soaking time exceeds 6 h, the adsorption capacity of the remover no longer increases.

[0113] In some specific embodiments, the soaking temperature is 50-90°C. At this temperature, the solubility of boric acid is high. Above 90°C, the solution tends to boil, which is not conducive to the deposition of boric acid on the microspheres.

[0114] In some specific embodiments, the drying temperature is 100–165°C, more preferably 120–140°C. At drying temperatures above 165°C, boric acid tends to decompose into metaboric acid. A temperature of 120–140°C ensures drying without decomposing boric acid, and also results in a shorter drying time.

[0115] In some specific embodiments, the sol-gel coating process includes:

[0116] The porous polymer microspheres are arranged in a single layer in a container filled with sol. The height of the sol in the container is 1 / 4 to 1 / 3 of the height of the remover particles. The porous polymer microspheres are rolled in the sol until the entire surface is covered with sol. The porous polymer microspheres are then removed.

[0117] The amount of sol applied should not be excessive; otherwise, a thicker colloid layer on the surface of the remover will severely reduce the adsorption rate of nonionic surfactants, resulting in insufficient removal efficiency. The colloid covering the microsphere surface should be as thin as possible to improve the adsorption rate and removal efficiency of nonionic surfactants, while ensuring that the entire surface of the microspheres is covered by the colloid. The remover prepared using the above coating method can achieve a maximum flow rate of 8 BV / h when reactivating sulfoneamine solution.

[0118] In some specific embodiments, the aging time is ≥7 days. If it is less than 7 days, the adhesion and stability of the colloid on the surface of the remover are insufficient, resulting in colloid shedding or fluctuating removal rates.

[0119] The hydrophobic descaling agent of the present invention can be specifically applied to the removal of nonionic surfactants from organic solutions, especially to the removal of nonionic surfactants from sulfolane. More specifically, it can be applied to the removal of nonionic surfactants from sulfoneamine solutions.

[0120] In some specific embodiments, the removing agent is applied to the removal of nonionic surfactants from a sulfonamide solution to provide a method for removing nonionic surfactants from a sulfonamide solution, the method comprising:

[0121] The sulfoneamine solution is first separated by electrodialysis to remove part of the alcohol amine, and the remaining solution is separated by the hydrophobic removal agent to remove the nonionic surfactant;

[0122] The solution from which nonionic surfactants have been removed is mixed with the alcoholic amines separated by electrodialysis to obtain a sulfoneamine solution from which nonionic surfactants have been removed.

[0123] In some specific embodiments, the percentage of alkanolamines separated by electrodialysis is ≥80%.

[0124] Alkylamines are weakly basic, and their effect on the ionization of boric acid (the active component of nonionic surfactants that complex and adsorbs it) in water increases with increasing concentration and decreases with decreasing concentration. When the concentration of alkylamines in the desulfurization solution is reduced to below 10%, their promoting effect on the ionization of boric acid becomes relatively small. To reduce the concentration of alkylamines in the desulfurization solution to below 10%, 78% or more of the alkylamines need to be separated.

[0125] In some specific embodiments, when separating alcoholic amines by electrodialysis, sulfonic acid cation exchange membranes and quaternary ammonium anion exchange membranes are used.

[0126] Electrodialysis is more effective at separating substances with stronger ionization capabilities. Alkylamines are weak electrolytes. The quaternary ammonium groups of the quaternary ammonium anion exchange membrane have strong electron-withdrawing properties, while the sulfonic acid groups of the sulfonic acid cation exchange membrane have strong electron-donating properties. These properties can generate a strong "attraction" on the anions and cations ionized from alkylamines, thereby promoting their ionization and achieving a removal rate of over 85%.

[0127] In some specific embodiments, nonionic surfactants in organic solutions are removed by immersion or rinsing. More preferably, nonionic surfactants in organic solutions are removed by rinsing. Compared with immersion, rinsing can create a larger concentration gradient, i.e., the difference between the concentration of nonionic surfactants in the solution and the concentration of nonionic surfactants on the removing agent, thus resulting in a higher removal rate.

[0128] In some specific embodiments, the operating parameters for removing nonionic surfactants from sulfonamide solutions by rinsing include: ambient temperature and pressure, and a flow rate of <9 BV / h for rinsing the hydrophobic desiccant with the sulfonamide solution, preferably 2 BV / h to 3 BV / h.

[0129] The volume of resin loaded in a resin column is called the bed volume (BV). If the flow rate of the solution through the resin column is 2 BV / h to 4 BV / h, the volume of solution passing through per hour is 2 to 4 times the resin bed volume. It takes time for nonionic surfactants in the solution to be adsorbed onto the remover. When using an adsorbent without sol coating, if the flow rate is too high (reaching 20 BV / h or higher), the removal rate is <60%. After the surface of the nonionic surfactant remover is covered with a colloid, the rate at which it adsorbs nonionic surfactants in the desulfurization solution decreases. Therefore, the contact time between the solution and the remover must be increased. If the flow rate reaches 9 BV / h or higher, the removal rate is <60%, and 2 BV / h to 3 BV / h is preferred.

[0130] Furthermore, after the hydrophobic desiccant becomes saturated with adsorbed nonionic surfactants, it can be regenerated using a nonpolar or moderately polar organic solvent. The interaction between nonionic surfactant molecules and nonpolar or moderately polar organic solvent molecules is stronger than their interaction with boric acid, allowing them to be separated from boric acid and thus desorbed, achieving regeneration of the desiccant. Preferably, the nonpolar or moderately polar organic solvent is selected from at least one of dichloromethane and ethyl acetate.

[0131] In a preferred embodiment of the present invention, the acrylate monomer is hexyl acrylate, the aliphatic diene crosslinking agent is ethylene glycol dimethacrylate, and the pore-forming agent is decane, decanol, or 2-ethyl-1-hexanoic acid; the silicate ester is tetraethyl orthosilicate, and the alkoxysilane is heptadecafluorodecyltrimeth(or ethoxy)silane.

[0132] Conventional polymer adsorbents are polymers formed using styrene as a monomer and divinylbenzene as a crosslinking agent. Because sulfolane has a strong affinity for phenyl groups, these adsorbents exhibit strong adsorption of sulfolane. The remover of this invention is a polymer prepared using acrylate as a monomer and an aliphatic diene as a crosslinking agent; neither the monomer nor the crosslinking agent contains phenyl groups. While the ester groups in acrylate have some adsorption capacity for sulfolane, the alkyl groups exhibit a shielding effect on the adsorption of sulfolane by the ester groups, and the greater the number of carbon atoms in the alkyl group, the stronger the shielding effect. However, an excessively large number of alkyl groups may generate long polyacrylate segments and linear acrylate homopolymers during the polymerization reaction, causing the prepared remover to agglomerate during use. The number of alkyl groups in the hexyl acrylate molecule can address both of these issues, satisfying the requirement of a sufficiently large shielding effect for weak sulfolane adsorption while preventing the remover from agglomerating during use. Ethylene glycol dimethacrylate, a preferred crosslinking agent, increases the swelling degree of the copolymer, resulting in a larger interchain distance in the final polymer. This not only facilitates the penetration of large molecular weight organic compounds such as surfactants, but also further weakens the polymer's affinity for sulfolane and enhances its affinity for nonionic surfactants due to the long-chain hydrocarbon groups. Using a porogen to create a porous structure allows surfactant molecules to reside within the pores, where the planes interact simultaneously, resulting in a superposition of potential energy and enhancing the interaction between the surfactant and the removal agent. Decane, decanol, and 2-ethyl-1-hexanoic acid are chosen as porogens to ensure the pore size of the prepared porous polymer is suitable for subsequent introduction of the active component without excessively weakening the superposition of potential energy across the planes. Introducing boric acid onto the inner pore surface of the prepared porous polymer allows the oxygen on the polyoxyethylene nonionic surfactant to donate electrons and complex with the boron atoms on the boric acid, while sulfolane cannot complex with it. This achieves selective adsorption of nonionic surfactants from sulfolane.

[0133] This invention further utilizes a sol to coat and modify the desorbent to be hydrophobic. In a preferred embodiment, tetraethyl orthosilicate and heptadecafluorodecyltrimeth(eth / propoxy)silane are hydrolyzed and polymerized to form a colloid with high drainage capacity and high organic molecule permeability, which covers the surface of the desorbent to obtain a hydrophobic desorbent. The desorbent modified in this way has a repulsive effect on water molecules. When it is used to remove nonionic surfactants in sulfoneamine solution, it significantly reduces the probability of contact between boric acid in the desorbent and water molecules in the desulfurization solution. Furthermore, the high organic molecule permeability of the colloid ensures that nonionic surfactant molecules can pass through the colloid and contact with boric acid for removal.

[0134] The present invention is illustrated below with specific embodiments, wherein all numerical specifications (e.g., temperature, time, concentration, and weight, including ranges for each) are generally approximate values ​​that may be changed in increments of 0.1 or 1.0 (+) or (-). All numerical specifications are to be understood as being preceded by the term "about".

[0135] Example 1

[0136] The unmodified removers 1-13 were prepared according to the following steps, and their performance was tested.

[0137] I. Preparation of the Removal Agent

[0138] 1) Mix the monomer, crosslinking agent and porogen in a molar ratio of 1:0.1:0.5 to obtain mixture 1;

[0139] 2) Mix mixture 1 with benzoyl peroxide at a mass ratio of 100:1 to obtain mixture 2;

[0140] 3) Hydroxyethyl cellulose, sodium chloride, and water are mixed in a mass ratio of 0.6:10:100 to obtain mixture 3;

[0141] 4) Mix mixture 2 and mixture 3 at a ratio of 1:3, turn on the stirrer, heat to 60-90℃ and react for 12 hours, filter out the microspheres, wash with anhydrous ethanol and deionized water 4 times respectively, and finally dry under vacuum at 60℃ for 18 hours.

[0142] 5) Transfer the microspheres to a 70℃ saturated boric acid solution (the mass ratio of boric acid solution to microspheres is 4.2:1, and the boric acid concentration of the 70℃ saturated boric acid solution is 16.7%, which is equivalent to a boric acid to microsphere mass ratio of 0.7:1) and soak for 5 hours. Filter the microspheres and dry them at 130℃ for 5 hours to obtain the removal agent.

[0143] Obtain by following the steps above:

[0144] Remover 1: The monomer, crosslinking agent and porogen used are, in order, hexyl acrylate, ethylene glycol dimethacrylate and 2-ethyl-1-hexanoic acid.

[0145] Remover 2: The monomer, crosslinking agent and porogen used are methyl acrylate, ethylene glycol dimethacrylate and 2-ethyl-1-hexanoic acid, respectively.

[0146] Remover 3: The monomer, crosslinking agent and porogen used are styrene, ethylene glycol dimethacrylate and 2-ethyl-1-hexanoic acid, respectively.

[0147] Remover 4: The monomer, crosslinking agent and porogen used are, in order, hexyl acrylate, divinylbenzene and 2-ethyl-1-hexanoic acid.

[0148] Remover 5: The monomers, crosslinking agents and porogens used are the same as those used in remover 1, namely hexyl acrylate, ethylene glycol dimethacrylate and 2-ethyl-1-hexanoic acid, but the molar ratio is changed to 1:0.35:0.5.

[0149] Remover 6: The monomer, crosslinking agent and porogen used are, in order, hexyl acrylate, ethylene glycol dimethacrylate and isooctanol.

[0150] Remover 7: The monomers, crosslinking agents and porogens used are the same as those used in remover 1, namely hexyl acrylate, ethylene glycol dimethacrylate and 2-ethyl-1-hexanoic acid, but the molar ratio is changed to 1:0.1:0.05.

[0151] Remover 8: Step 5) Change the mass ratio of boric acid to microspheres to 0.05:1.

[0152] Remover 9: In step 5), the soaking time of the microspheres in the 70°C boric acid solution was changed to 0.4 hours.

[0153] Remover 10: Step 5) Change the drying temperature of the microspheres to 166℃.

[0154] Remover 11: The monomer, crosslinking agent and porogen used are, in order, hexyl acrylate, ethylene glycol dimethacrylate and n-decane.

[0155] Remover 12: The monomer, crosslinking agent and porogen used are, in order, hexyl acrylate, ethylene glycol dimethacrylate and decyl alcohol.

[0156] Remover 13: The monomers and crosslinking agents used are hexyl acrylate and ethylene glycol dimethacrylate, respectively, without porogens.

[0157] II. Preparation of sulfolane solution

[0158] The most common nonionic surfactant in natural gas desulfurization solutions is polyoxyethylene alkyl alcohol ether-20. Polyoxyethylene alkyl alcohol ether-20 is added to sulfolane to prepare a sulfolane solution containing 0.4% (mass fraction) of polyoxyethylene alkyl alcohol ether-20.

[0159] III. De-icing Agent Performance Testing

[0160] Remover agents 1-13 and activated carbon were respectively packed into 14 glass columns with an inner diameter of 25 mm, each with a loading amount of 25 g. More than 500 g of the prepared sulfolane solution was injected into the top of each of the 14 glass columns, allowing the solution to flow from top to bottom through the activated carbon or each remover agent at a rate of 4 BV / h. Finally, nitrogen gas was used to blow the activated carbon and remover agents from the top of the glass columns. The sulfolane solution flowing out of the bottom of each glass column was collected and weighed (m). The mass fraction (w) of polyoxyethylene alkyl alcohol ether-20 in the sulfolane solution was determined. The removal rate and selectivity of the nonionic surfactant by the activated carbon and each remover agent were calculated using the following method:

[0161] Removal rate of nonionic surfactant = (0.4% × 500 – w × m) ÷ (0.4% × 500)

[0162] The activated carbon and each stripping agent were washed from top to bottom with 100 mL of ethyl acetate to elute the polyoxyethylene alkyl alcohol ether-20 and sulfolane adsorbed on the activated carbon and each stripping agent. The mass of each of these two substances was determined by multiplying the mass of the eluent by the content of each of these two substances in the eluent.

[0163] Selective absorption ratio = Amount of polyoxyethylene alkyl alcohol ether-20 eluted / Amount of sulfolane eluted

[0164] The results of the removal rate and selective adsorption ratio of nonionic surfactants by activated carbon and various removal agents are shown in Table 1.

[0165] Table 1. Removal rate and selectivity of each remover for nonionic surfactants

[0166] Removal rate Select the absorption ratio Activated carbon 6.6％ 0.1 Remover 1 98.3％ 56.1 Remover 2 92％ 18.5 Remover 3 51％ 1.1 Remover 4 53％ 1.2 Remover 5 57％ 33.5 Remover 6 81％ 47.6 Remover 7 6.3％ 4.2 Remover 8 7.5％ 5 Remover 9 10％ 6.1 Remover 10 38％ 22.4 Remover 11 96.5％ 55.4 Remover 12 95.1％ 55.9 Remover 13 6.1％ 4.3

[0167] The experimental results shown in Table 1 indicate that removers 3 and 4, prepared using monomers or crosslinking agents containing phenyl groups, not only have a selectivity ratio lower than 2, but also a removal rate of less than 60% for nonionic surfactants. Remover 5, prepared with a molar ratio of crosslinking agent to monomer greater than 0.3, exhibits selective adsorption of nonionic surfactants in sulfolane, with a selectivity ratio of 33.5, much greater than 2, but a removal rate of less than 60%. Removers 7, 8, and 9, prepared with a porogen to monomer mass ratio lower than 0.1, a boric acid to microsphere mass ratio lower than 0.1, and a boric acid soaking time of less than 0.5 hours, all have very low removal rates of less than 20% due to their adsorption capacity of less than 10 mg / g. Remover 10, prepared by changing the microsphere drying temperature to 166℃, also has a low removal rate of less than 40% because boric acid decomposes into metaboric acid.

[0168] Desorbent 2, prepared using methyl acrylate as a monomer, also achieves a removal rate of over 90% and a selectivity greater than 10 (sulfolane loss rate <1%), meeting the requirements for practical production use. However, it does not have the selectivity greater than 50 of the desorbent prepared using the optimal monomer hexyl acrylate. Desorbent 6, prepared using isooctanol as a porogen, has a selectivity of 47.5 and a relatively high removal rate of over 80%, meeting the requirements for practical production use. However, it does not have the removal rate greater than 95% of the desorbent prepared using the optimal porogens n-decane, decanol, and 2-ethyl-1-hexanoic acid. Desorbent 1, prepared under the optimal conditions, exhibits outstanding performance, with a removal rate exceeding 98% and a selectivity greater than 56.

[0169] The particle size, specific surface area, average pore size, and pore volume of the removal agents 1, 2, 6, 11, and 12, which meet the requirements of actual production use, were determined by sieving, BET method, and the results are shown in Table 2.

[0170] Table 2

[0171]

[0172] The results shown in Table 2 indicate that the particle size distribution of the remover prepared under the optimal conditions is (0.2–1.0) mm; and the specific surface area is (300–400) m². 2 / g; average pore size is (15~27)nm, and pore volume is in the range of (1.5~2.0)mL / g.

[0173] Example 2

[0174] This embodiment explores the removal effect of remover 1 on nonionic surfactants at different flow rates.

[0175] The removing agent 1 was filled into six glass columns with an inner diameter of 25 mm, with a filling amount of 25 g in each column. The six glass columns were numbered sequentially as 1. # ~6 # 500g of a sulfolane solution containing 0.4% (mass fraction) polyoxyethylene alkyl alcohol ether-20 was injected into the top of each of the six glass columns. The solution was then allowed to flow from top to bottom through each glass column at a certain flow rate. # ~6 # The flow rates were successively 0.1 BV / h, 2 BV / h, 4 BV / h, 6 BV / h, 7 BV / h, and 20 BV / h. Finally, nitrogen gas was used to blow activated carbon and the removing agent from the top of the glass column. The sulfolane solution flowing out from the bottom of each glass column was collected and weighed (m). The mass fraction (w) of polyoxyethylene alkyl alcohol ether-20 in the sulfolane solution was determined. The removal rate and selectivity of the removing agent for the nonionic surfactant were calculated using the following method:

[0176] Removal rate of nonionic surfactant = (0.4% × 500 – w × m) ÷ (0.4% × 500)

[0177] The removal rates of nonionic surfactants by the remover 1 at different flow rates are shown in Table 3.

[0178] Table 3. Removal rate of nonionic surfactant by remover 1 at different flow rates.

[0179] <![CDATA[1 # Pillar]]> <![CDATA[2 # Pillar]]> <![CDATA[3 # Pillar]]> <![CDATA[4 # Pillar]]> <![CDATA[5 # Pillar]]> <![CDATA[6 # Pillar]]> Solution flow rate 0.1 BV / h 2BV / h 4BV / h 6BV / h 7BV / h 20BV / h Removal rate 83.7％ 98.5％ 98.5％ 98.3％ 93.2％ 59.4％

[0180] The experimental results shown in Table 3 indicate that the removal rates at flow rates of 4 BV / h to 6 BV / h and 2 BV / h are essentially the same, both exceeding 98%. A faster flow rate is preferable as it saves solution treatment time. However, excessively fast flow rates reduce the removal rate due to insufficient contact time; the removal rate drops to 93.2% at 7 BV / h and falls below 60% at 20 BV / h. Conversely, a flow rate as low as 0.1 BV / h, approaching immersion, also results in insufficient removal rates, below 85%. Therefore, a rinsing method with a flow rate of 4 BV / h to 6 BV / h is preferred for treating the solution.

[0181] Example 3

[0182] In this embodiment, different regeneration solutions were used to regenerate the remover, and the removal effect of the regenerated remover on nonionic surfactants was verified.

[0183] 1) Take 2 from Example 2 # Column, 3 # Column, 4 # The columns were regenerated by rinsing with 100 mL of ethanol, dichloromethane, and ethyl acetate, respectively. Then, 500 g of sulfolane solution containing 0.4% (mass fraction) of polyoxyethylene alkyl alcohol ether-20 was injected into the top of each glass column. The flow rate of the solution was 4 BV / h. The removal rate of nonionic surfactant by the remover 1 after regeneration with ethanol, dichloromethane, and ethyl acetate was tested. The results are shown in Table 4.

[0184] Table 4 shows the removal rates of nonionic surfactants by agent 1 after regeneration with different regenerable solutions.

[0185] <![CDATA[2 # Pillar]]> <![CDATA[3 # Pillar]]> <![CDATA[4 # Pillar]]> regenerated liquid ethanol dichloromethane Ethyl acetate Removal rate 56.8％ 98.3％ 98.2％

[0186] The experimental results shown in Table 4 indicate that the removal rate dropped significantly to below 60% after using ethanol regeneration agent 1; however, the removal rate remained above 98% when using dichloromethane and ethyl acetate regeneration agent 1.

[0187] 2) Continue to regenerate columns #3 and #4 by rinsing with 100 mL of dichloromethane and ethyl acetate, respectively. Then, inject 500 g of a sulfolane solution containing 0.4% (mass fraction) polyoxyethylene alkyl alcohol ether-20 into the top of each glass column, at a flow rate of 4 BV / h. Repeat the above operation to test the removal rate of remover 1 after multiple regenerations. The results are shown in Table 5.

[0188] Table 5. Removal rate of nonionic surfactants after multiple regenerations of the removal agent 1.

[0189]

[0190] The experimental results shown in Table 5 indicate that when using remover 1 to remove nonionic surfactants from sulfolane solution, the removal rate can be maintained at over 98% of the initial removal rate after more than 100 saturation and regeneration cycles, demonstrating good stability.

[0191] Example 4

[0192] Prepare hydrophobic removal agents 1-7 according to the following steps and perform performance tests.

[0193] I. Preparation of hydrophobic removal agents 1-7

[0194] 1) Mix tetraethyl orthosilicate with ethanol, then add water adjusted to pH 3 (using hydrochloric acid to adjust the pH of the water), stir and mix. Add fluorosilane and continue stirring for 8 hours. After standing for 20 hours, a sol is obtained. The molar ratio of tetraethyl orthosilicate:ethanol:water:fluorosilane is 1:3:0.5:0.6.

[0195] 2) Arrange the nonionic surfactant removal agent particles (removing agent 1) in a single layer in a container containing the sol prepared in step 1). The height of the sol in the container is 1 / 4 of the height of the removal agent particles. Let the removal agent roll in the sol until the surface of the removal agent is completely covered with the sol, and then remove the removal agent.

[0196] 3) Allow the remover applied in the second step to age for 7 days.

[0197] Obtain by following the steps above:

[0198] Hydrophobic removal agent 1: The fluorosilane used in step 1) is heptadecafluorodecyltrimethoxysilane;

[0199] Hydrophobic removal agent 2: The fluorosilane used in step 1) is tridecafluorooctyltrimethoxysilane;

[0200] Hydrophobic removal agent 3: The fluorosilane used in step 1) is nonafluorohexyltriethoxysilane;

[0201] Hydrophobic remover 4: In step 1), the fluorosilane used is heptadecafluorodecyltrimethoxysilane, but the molar ratio of tetraethyl orthosilicate and ethanol is changed to 1:9, that is, the molar ratio of tetraethyl orthosilicate:ethanol:water:fluorosilane is 1:9:0.5:0.6.

[0202] Hydrophobic removal agent 5: In step 1), the fluorosilane used is heptadecafluorodecyltrimethoxysilane, but the pH of the water is adjusted to a concentration of hydrochloric acid of 0.2 mol / L, at which point the pH is <1, approximately 0.7.

[0203] Hydrophobic removal agent 6: In step 1), the fluorosilane used is heptadecafluorodecyltrimethoxysilane, but the pH of the water is adjusted to 1.

[0204] Hydrophobic Removal Agent 7: In step 1), the fluorosilane used is heptadecafluorodecyltrimethoxysilane, but the molar ratio of tetraethyl orthosilicate to water is changed to 1:0.4, that is, the molar ratio of tetraethyl orthosilicate: ethanol: water: fluorosilane is 1:3:0.4:0.6.

[0205] II. Preparation of sulfoneamine solution

[0206] Polyoxyethylene alkyl alcohol ether-20 was added to a sulfonamine solution (sulfolane: N-methyldiethanolamine: water mass ratio = 25:45:30) to prepare a sulfonamine solution containing 0.4% (mass fraction) of polyoxyethylene alkyl alcohol ether-20.

[0207] III. Performance Testing of Hydrophobic Removing Agents

[0208] 1) Fill 7 of the hydrophobic removal agents 1-7 into 7 glass columns with an inner diameter of 25 mm, and fill each column with 25 g.

[0209] 2) Divide 3500g of the above-mentioned sulfonamine solution containing 0.4% (mass fraction) of polyoxyethylene alkyl alcohol ether-20 into 7 equal portions. Separate 80% N-methyldiethanolamine from each portion of the solution by electrodialysis. Then inject the solutions into the above 7 glass columns (inject from the top of the glass column). Let the solution flow from top to bottom through each stripping agent at a rate of 4 BV / h. Use nitrogen gas to blow off the stripping agent from the top of the glass column. Collect the solution flowing out of the bottom of each glass column in seven beakers. Add the N-methyldiethanolamine separated by the electrodialysis instrument to the solution in each beaker and weigh it. Measure the mass fraction w of polyoxyethylene alkyl alcohol ether-20 in the solution.

[0210] The electrodialysis method specifically includes the following steps: Quaternary ammonium anion exchange membrane and sulfonic acid cation exchange membrane are selected as the anion and cation exchange membranes, respectively. The solution is added to the electrodialysis instrument, the power is turned on, the voltage is adjusted to 220V, and after running for 5 minutes, the solution in the concentration chamber is taken out, which is the separated alkanolamine. The solution in the desalination chamber is injected into a glass column for further nonionic surfactant removal.

[0211] 3) Calculate the removal rate of nonionic surfactants by each hydrophobic removal agent. The calculation method is as follows:

[0212] Removal rate of nonionic surfactant = (0.4% × 400 - w × m) ÷ (0.4% × 400)

[0213] The removal rates of nonionic surfactants by various hydrophobic removal agents are shown in Table 6.

[0214] Table 6. Removal rates of nonionic surfactants by various hydrophobic removers

[0215]

[0216] The experimental results shown in Table 6 indicate that the sol coatings prepared with tridecafluorooctyltrimethoxysilane and nonafluorohexyltriethoxysilane, respectively, for hydrophobic removers 2 and 3 resulted in a low nonionic surfactant removal rate (<60%). The use of excessive ethanol in the sol coating for hydrophobic remover 4, and the excessively high acidity during sol preparation for hydrophobic remover 5, all contributed to a low nonionic surfactant removal rate (<60%). While the pH of hydrophobic remover 6 was pH=1 during sol preparation, achieving a removal rate above 60%, it was not optimal. Under the preferred conditions, hydrophobic remover 1 exhibited a very high nonionic surfactant removal rate (>98%).

[0217] Example 5

[0218] I. Preparation of hydrophobic removal agents 8-10

[0219] The preparation of the hydrophobic removal agent is the same as in Example 4.

[0220] Remover 8: In step 1), the fluorosilane used is heptadecafluorodecyltrimethoxysilane, but the molar ratio of tetraethyl orthosilicate to heptadecafluorodecyltrimethoxysilane is changed to 1:0.5, that is, the molar ratio of tetraethyl orthosilicate: ethanol: water: fluorosilane is 1:3:0.4:0.5.

[0221] Remover 9: In step 1), the fluorosilane used is heptadecafluorodecyltrimethoxysilane, but the molar ratio of tetraethyl orthosilicate to heptadecafluorodecyltrimethoxysilane is changed to 1:1.6, that is, the molar ratio of tetraethyl orthosilicate: ethanol: water: fluorosilane is 1:3:0.4:1.6.

[0222] Remover 10: In step 1), the fluorosilane used is heptadecafluorodecyltrimethoxysilane, but the molar ratio of tetraethyl orthosilicate to heptadecafluorodecyltrimethoxysilane is changed to 1:1.5, that is, the molar ratio of tetraethyl orthosilicate: ethanol: water: fluorosilane is 1:3:0.4:0.5.

[0223] II. Preparation of sulfoneamine solution

[0224] A sulfoneamine solution without nonionic surfactants was prepared by mixing sulfolane, N-methyldiethanolamine, and water in a mass ratio of 25:45:30.

[0225] III. Performance Testing of Hydrophobic Removing Agents

[0226] Take 25g each of hydrophobic removal agent 1 and hydrophobic removal agents 8-10 and place them in 200g of sulfonamide solution without nonionic surfactant. Shake at 150rpm for 40 days, then separate the removal agents and test their performance according to the method described in Section 3 of Example 1. The test results are shown in Table 7.

[0227] Table 7. Removal rates of nonionic surfactants by various removers

[0228] Hydrophobic Removal Agent 1 Hydrophobic Removal Agent 8 Hydrophobic Removal Agent 9 Hydrophobic removal agent 10 Removal rate 98.0％ 92.0％ 92.9％ 98.1％

[0229] The experimental results shown in Table 7 indicate that the hydrophobic removal agents prepared with molar ratios of heptadecafluorodecyltrimethoxysilane and tetraethyl orthosilicate of 0.6 and 1.5 exhibit good stability, maintaining a removal rate of approximately 98% after immersion in sulfonamide solution for 40 days. However, the hydrophobic removal agents prepared with molar ratios of heptadecafluorodecyltrimethoxysilane and tetraethyl orthosilicate of 0.5 and 1.6 show poor stability, with their removal rate falling below the initial 95% after immersion in sulfonamide solution for 40 days.

[0230] Example 6

[0231] I. Preparation of hydrophobic removal agent 11

[0232] The preparation of the hydrophobic removal agent is the same as in Example 4.

[0233] Remover 11: The fluorosilane used in step 1) is heptadecafluorodecyltrimethoxysilane, but in step 2) the remover is applied by immersion.

[0234] II. Performance Testing of Hydrophobic Removing Agents

[0235] Hydrophobic removal agent 1 was packed into nine glass columns with an inner diameter of 25 mm, with a loading amount of 25 g in each column. The nine glass columns were numbered sequentially as 1. # -9 # The performance of the desiccant was tested according to the method described in Section 3 of Example 4, except that the flow rates of the sulfonamine solution containing the nonionic surfactant through each desiccant from top to bottom were 0.1, 1, 2, 3, 4, 6, 7, 8, and 9 BV / h, respectively. The test results are shown in Table 8.

[0236] Table 8. Removal rate of nonionic surfactant by hydrophobic remover 1 at different flow rates

[0237]

[0238] The hydrophobic removal agent 11 was filled into nine glass columns with an inner diameter of 25 mm, with a filling amount of 25 g in each column. The nine glass columns were numbered 10 sequentially. # -17 # The performance of the desiccant was tested according to the method described in Section 3 of Example 4, except that the flow rates of the sulfonamine solution containing the nonionic surfactant through each desiccant from top to bottom were 0.1, 1, 2, 3, 4, 6, 7, and 8 BV / h, respectively. The test results are shown in Table 9.

[0239] Table 9. Removal rate of nonionic surfactant by hydrophobic desiccant 11 at different flow rates.

[0240]

[0241]

[0242] The experimental results shown in Table 8 indicate that the optimal flow rate for rinsing the hydrophobic desiccant with sulfonamide solution is 2 BV / h to 3 BV / h. Compared with the results in Table 2, after the surface of the nonionic surfactant desiccant is covered with colloid, its adsorption rate of nonionic surfactants in the desulfurization solution decreases. Therefore, the contact time between the solution and the desiccant must be increased. When the flow rate reaches 9 BV / h or higher, the removal rate is <60%, with 2 BV / h to 3 BV / h being the preferred values.

[0243] Comparing the experimental results shown in Tables 8 and 9, it can be seen that the hydrophobic remover prepared by immersion coating has a lower removal rate than the hydrophobic remover prepared by the preferred coating method at the same flow rate.

[0244] Example 7

[0245] I. Preparation of hydrophobic removal agent 12

[0246] The preparation of the hydrophobic removal agent is the same as in Example 4.

[0247] Remover 12: The fluorosilane used in step 1) is heptadecafluorodecyltrimethoxysilane, but the aging time after applying the remover sol in step 3) is changed to 6 days.

[0248] II. Performance Testing of Hydrophobic Removing Agents

[0249] The performance of hydrophobic remover 1 and hydrophobic remover 12 was tested according to the method described in Section 3 of Example 4. The difference was that after treating 500g of sulfoneamine solution containing 0.4% (mass fraction) of polyoxyethylene alkyl alcohol ether-20, the hydrophobic remover was regenerated with ethyl acetate, and then the performance of the regenerated hydrophobic remover was tested. The test results are shown in Table 10.

[0250] Table 10 Removal rates after regeneration of hydrophobic removal agent 1 and hydrophobic removal agent 12

[0251]

[0252] The experimental results shown in Table 10 indicate that the hydrophobic remover 1 prepared with a sol-forming time of 7 days has good stability after regeneration, but the hydrophobic remover 12 prepared with a sol-forming time of less than 6 days has poor stability after regeneration.

[0253] Example 8

[0254] 1) Pack 25g of activated carbon into glass column #18 with an inner diameter of 25mm; pack 25g of activated carbon into glass column #19. # and 22 # 25g of uncoated solvent-based remover 1 was packed into a glass column with an inner diameter of 25mm; hydrophobic remover 1 was then packed into two glass columns (numbered 20) with an inner diameter of 25mm respectively. # ,twenty one # In each of the following, the filling amount is 25g.

[0255] 2) Inject 500g of a sulfoneamine solution containing 0.4% (mass fraction) of polyoxyethylene alkyl alcohol ether-20 into the above 18 # A glass column (injected from the top of the glass column) was used to allow the solution to flow from top to bottom through activated carbon at a rate of 4 BV / h, and the removal rate of the activator for polyoxyethylene alkyl alcohol ether-20 was tested.

[0256] 3) Inject 500g of a sulfonamine solution containing 0.4% (mass fraction) of polyoxyethylene alkyl alcohol ether-20 into the above 19 # A glass column (injected from the top of the glass column) was used to allow the solution to flow from top to bottom through the unhydrophobically modified remover 1 at a rate of 4 BV / h. The remover was then regenerated with ethyl acetate. The above operation was repeated after regeneration to test the removal rate of remover 1 after regeneration.

[0257] 4) First, separate 75% N-methyldiethanolamine from 500g of a sulfoneamine solution containing 0.4% (mass fraction) of polyoxyethylene alkyl alcohol ether-20 using electrodialysis, and then inject the solution into the above-mentioned 20... # A glass column (injected from the top of the glass column) was used to allow the solution to flow from top to bottom through the hydrophobic removal agent 1 at a rate of 4 BV / h. The hydrophobic removal agent 1 was then regenerated with ethyl acetate. The above operation was repeated after regeneration to test the removal rate of the hydrophobic removal agent 1 after regeneration.

[0258] 5) First, separate 80% N-methyldiethanolamine from 500g of a sulfoneamine solution containing 0.4% (mass fraction) of polyoxyethylene alkyl alcohol ether-20 using electrodialysis, and then inject the solution into the above-mentioned 21 #A glass column (injected from the top of the glass column) was used to allow the solution to flow from top to bottom through the hydrophobic removal agent 1 at a rate of 4 BV / h. The hydrophobic removal agent 1 was then regenerated with ethyl acetate. The above operation was repeated after regeneration to test the removal rate of the hydrophobic removal agent 1 after regeneration.

[0259] 6) First, separate 80% N-methyldiethanolamine from 500g of a sulfoneamine solution containing 0.4% (mass fraction) of polyoxyethylene alkyl alcohol ether-20 using electrodialysis, and then inject the solution into the above-mentioned 22 # A glass column (injected from the top of the glass column) was used to allow the solution to flow from top to bottom through the unhydrophobically modified remover 1 at a rate of 4 BV / h. The remover 1 was then regenerated with ethyl acetate. The above operation was repeated after regeneration to test the removal rate of the removedr 1 after regeneration.

[0260] The test results are shown in Table 11.

[0261] Table 11

[0262]

[0263]

[0264] The experimental results shown in Table 11 are as follows:

[0265] ① Using existing technology, activated carbon is used to separate polyoxyethylene alkyl alcohol ether-20 from sulfoneamine solution. The separation effect is very poor, with a removal rate of only 6.5%.

[0266] ② When a nonionic surfactant without hydrophobic modification is used to directly treat a sulfonamine solution containing 0.4% (mass fraction) of polyoxyethylene alkyl alcohol ether-20, the removal rate decreases to 86.3% (<90%) of the initial removal rate after 40 regenerations of the remover, indicating poor stability. Even if 80% of the sulfonamine is separated by electrodialysis before treatment, the removal rate decreases to 83.5% (<85%) of the initial removal rate after 80 regenerations of the remover, indicating poor stability.

[0267] ③ A hydrophobic removal agent was used to treat a sulfonamine solution containing 0.4% (mass fraction) of polyoxyethylene alkyl alcohol ether-20. Before treatment, 75% of the sulfonamine was separated by electrodialysis. After the removal agent was regenerated 40 times, the removal rate was close to the initial removal rate. After 101 regenerations, the removal rate was 96.0% (>95%) of the initial removal rate, showing good stability.

[0268] ④ A hydrophobic removal agent was used to treat a sulfonamine solution containing 0.4% (mass fraction) of polyoxyethylene alkyl alcohol ether-20. Before treatment, 80% of the sulfonamine was separated by electrodialysis. After the removal agent was regenerated 101 times, the removal rate could still reach 98.9% (>98%) of the initial removal rate, showing excellent stability.

[0269] Combining points ② and ③ with the data in Table 5, it can be seen that the nonionic surfactant remover without hydrophobic modification in this invention achieves a removal rate of over 98% for nonionic surfactants in sulfolane. Even after more than 100 saturation and regeneration cycles, the removal rate remains above 98% of the initial removal rate. However, when used in a sulfoneamine desulfurization solution composed of sulfolane and alkanolamine, there is a problem of slow loss of the active component boric acid, leading to a gradual decrease in the removal rate. After 80 saturation and regeneration cycles, the removal rate drops to below 84% of the initial removal rate, resulting in poor stability and low economic efficiency. This invention has found that the slow loss of the active component boric acid is due to the alkanolamine promoting the dissolution of boric acid. Boric acid is not easily soluble in cold water. Alkanolamine is weakly alkaline, and the hydroxide ions ionized in water promote the partial ionization of boric acid in water, increasing its solubility in the desulfurization solution. The higher the concentration of alkanolamine, the greater the promoting effect. The sulfonamide solution was treated with a hydrophobic removal agent, and 80% of the amines were separated by electrodialysis before treatment. After the removal agent was regenerated 101 times, the removal rate could still reach 98.9% of the initial removal rate, which showed excellent stability.

[0270] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all the implementation methods here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A method for preparing a hydrophobic remover of a nonionic surfactant, wherein, The preparation method includes the following steps: A porous polymer microsphere is obtained by suspending and copolymerizing acrylate monomers, aliphatic diene crosslinking agents, and pore-forming agents in water; the porous polymer microspheres are then immersed in a boric acid solution to load boric acid, and then the microspheres are filtered out and dried. The hydrophobic remover is obtained by coating the surface of porous polymer microspheres loaded with boric acid with a sol and then aging them. The sol is prepared by a sol-gel method using silicate ester and alkoxysilane, wherein the structural formula of the alkoxysilane is as follows: Wherein, R1 is a C1-C10 alkyl group, and R2 is a C5-C20 fluoroalkyl group; The structural formula of the acrylate monomer is: Wherein R is a C1-C5 alkyl group; or the acrylate monomer is hexyl acrylate; The pore-forming agent is selected from at least one of isooctyl alcohol, n-decane, decanol, and 2-ethyl-1-hexanoic acid; The molar ratio of the acrylate monomer, aliphatic diene crosslinking agent, and porogen is 1: (0.07~0.3): (0.1~0.8).

2. The preparation method according to claim 1, wherein, The silicate ester is tetraethyl orthosilicate.

3. The preparation method according to claim 1, wherein, In the alkoxysilane, R1 is a C1-C5 alkyl group, and R2 is nonafluorohexyl, tridecafluorooctyl, or heptadecafluorodecyl.

4. The preparation method according to claim 1, wherein, The aliphatic diene crosslinking agent is ethylene glycol dimethacrylate.

5. The preparation method according to claim 1, wherein, The porous polymer microspheres have a particle size distribution of 0.2 mm to 1.0 mm; The porous polymer microspheres loaded with boric acid have a specific surface area of ​​300 m². 2 / g ~ 400 m 2 / g, with an average pore size of 50nm ~ 110nm and a pore volume of 1.5 mL / g ~ 2.0mL / g.

6. The preparation method according to claim 1, wherein, The sol is prepared by the following steps: The silicate ester was mixed with ethanol, then added to acidic water and mixed again. Alkoxysilane was then added and the mixture was continued for 8 h to 12 h. After standing for 20 h to 40 h, the sol was obtained. The molar ratio of silicate ester to ethanol was 1: (3 to 8); the molar ratio of silicate ester to alkoxysilane was 1: (0.6 to 1.5).

7. The preparation method according to claim 6, wherein, The acidic water is adjusted to a pH of 2-3 by adding acid dropwise.

8. The preparation method according to claim 6, wherein, The molar ratio of the silicate ester to water is 1:(0.5~1.1).

9. The preparation method according to claim 1, wherein, The boric acid solution is a saturated boric acid solution at 80~90℃.

10. The preparation method according to claim 1, wherein, The mass ratio of boric acid to porous polymer microspheres is >0.

1.

11. The preparation method according to claim 1, wherein, The soaking time is >0.5 h, and the soaking temperature is 50~90℃.

12. The preparation method according to claim 1, wherein, The drying temperature is 100~165℃.

13. A hydrophobic remover for nonionic surfactants, obtained by the preparation method according to any one of claims 1-12.

14. The use of the remover of claim 13 in the removal of nonionic surfactants in organic solutions.

15. A method for removing nonionic surfactants from a sulfoneamine solution, wherein, The method includes: The sulfoneamine solution is first separated by electrodialysis to remove part of the alcohol amine, and the remaining solution is separated by the hydrophobic removal agent described in claim 13 to remove the nonionic surfactant; The solution from which nonionic surfactants have been removed is mixed with the alcoholic amines separated by electrodialysis to obtain a sulfoneamine solution from which nonionic surfactants have been removed.

16. The method according to claim 15, wherein, The percentage of alcoholic amines separated by electrodialysis is ≥80%; When separating alcoholic amines by electrodialysis, sulfonic acid cation exchange membranes and quaternary ammonium anion exchange membranes are used.

17. The method according to claim 15, wherein, Nonionic surfactants in sulfoneamine solutions are removed by soaking or rinsing. The operating parameters for removing nonionic surfactants from sulfonamide solutions by rinsing include: ambient temperature and pressure, and a flow rate of <9 BV / h for rinsing the hydrophobic surfactant with the sulfonamide solution.

18. The method according to claim 17, wherein, The flow rate of the sulfonamide solution used to rinse the hydrophobic removing agent was 2 BV / h to 3 BV / h.

19. The method according to claim 17, wherein, After the remover becomes saturated with adsorbed nonionic surfactants, it is regenerated using a weakly polar or moderately polar organic solvent.

20. The method according to claim 19, wherein, The weakly polar or moderately polar organic solvent is selected from dichloromethane and / or ethyl acetate.

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