Non-ionic surface active agent removing agent and preparation method and application thereof

Abstract

The invention discloses a nonionic surfactant removing agent as well as a preparation method and application thereof. The removal agent is porous polymer microspheres loaded with boric acid in pore channels, the porous polymer microspheres are obtained through suspension copolymerization of an acrylate monomer, an aliphatic diene cross-linking agent and a pore-foaming agent in water, and then the porous polymer microspheres are added into a boric acid solution to be soaked and loaded with the boric acid, so that the removal agent is obtained. The removal agent disclosed by the invention has high selectivity on the nonionic surfactant and the sulfolane, and the removal of the nonionic surfactant in a desulfurization solution containing the sulfolane can be realized. Specifically, the active component boric acid in pores of the porous polymer microspheres can be complexed with the entering nonionic surfactant and cannot be complexed with the sulfolane, so that selective adsorption of the active component boric acid and the entering nonionic surfactant is realized, deep removal of the nonionic surfactant in the sulfolane is realized, and the loss rate of the sulfolane is low; meanwhile, new impurities are not introduced after the non-ionic surface active agent in the sulfolane is removed.

Description

Technical Field

[0001] The invention relates to the field of polymer functional materials, and in particular to a non-ionic surfactant remover and a preparation method and application thereof. Background Art

[0002] Many raw natural gases extracted from underground reservoirs contain impurities such as H2S and organic sulfur and cannot be used directly. They must be desulfurized and purified before they can become commercial natural gas. Commercial natural gas specifies the sulfur content, and the total sulfur index is currently required to be ≤20mg / m 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 ≤20mg / m 3 Therefore, the demand for organic sulfur removal technology and organic sulfur removal solution in the field of natural gas purification is rapidly increasing.

[0004] Sulfolane is an excellent solvent for organic sulfur, with a high organic sulfur removal rate. Sulfolane is used as the preferred solvent for removing organic sulfur from natural gas. The number of purification plants using sulfolane and physical and chemical desulfurization solutions based on sulfolane is increasing rapidly.

[0005] During the natural gas purification process, the desulfurization solution is easily contaminated and deteriorated by the residues of upstream mining operations. The contaminated and foamed desulfurization solution is the most common and widespread problem in the natural gas purification production process, and is the main factor restricting the stable production and increase of the natural gas purification process. Therefore, the amine liquid resurrection technology that can remove the foaming pollutants in the desulfurization solution and restore the performance of the desulfurization solution is a key technology to ensure the stable production of the natural gas purification plant. However, when the existing amine liquid resurrection technology is used for cyclopentane sulfone and cyclopentane-based physical and chemical desulfurization solutions, it cannot effectively separate the foaming substances therein. The contaminated and foamed desulfurization solution leads to unqualified product natural gas quality, unstable operation of the natural gas purification device, and shutdown. These problems cannot be solved, which seriously affects normal production. Therefore, the demand for the removal technology of foaming substances in cyclopentane sulfone in the field of natural gas purification is very urgent.

[0006] Various surfactants in the residues of natural gas extraction operations are the cause of the foaming of the desulfurization solution. For example, non-ionic surfactants are used in foaming, demulsification, corrosion inhibition, drilling, and oil displacement agents. To solve the problem of foaming in the desulfurization solution, these surfactants must be removed.

[0007] Anionic and cationic surfactants can be ionized in aqueous solution, and their ionization is very different from that of sulfolane. After adding water to sulfolane, the interaction between anionic and cationic surfactant molecules and sulfolane molecules becomes weak, so the development of anionic and cationic surfactant removers in sulfolane can find a technical breakthrough from these property differences; however, the polarity, magnetism, ionization, organicity and inorganicity of non-ionic surfactants are extremely similar to those of sulfolane molecules, and the affinity between them and sulfolane molecules is very strong. It is very suitable to select sulfolane for extracting non-ionic surfactants, but it is very difficult to separate non-ionic surfactants from sulfolane. Various existing adsorbent materials have no selectivity for the adsorption of sulfolane and non-ionic surfactants. In the presence of high-concentration sulfolane (the concentration of sulfolane in the physical and chemical desulfurization solution is 50 times or more than the concentration of non-ionic surfactants), the removal rate of non-ionic surfactants is extremely low, less than 10%, and the removal rate by distillation is also very low, less than 30%. Because a few hundred ppm of surfactant can cause severe foaming in the desulfurization solution, the depth of surfactant removal in the desulfurization solution is very high. The separation of sulfolane and surfactant is difficult to achieve, and deep removal is even more difficult. Therefore, sulfolane has been used in the field of natural gas purification for many years, and the problem of how to revive it after being contaminated and foamed has not been solved. The only way to restore production is to replace the new solvent, and the contaminated solution replaced out of the device is treated as waste liquid. The waste liquid generated by a single desulfurization device due to contamination is usually as high as more than 400 tons. Because the organic content of sulfolane desulfurization solution is as high as 70% or more, and it also contains toxic components such as hydrogen sulfide, it is a hazardous waste that is very difficult and expensive to dispose of, which has caused a great economic burden and environmental pressure on the purification plant.

[0008] Existing purification technologies for deteriorated sulfolane include ion exchange separation, precipitation separation, activated carbon adsorption, and decomposition. 1) Ion exchange separation, using anion exchange resin to purify deteriorated sulfolane, such as patents US5053137, CN1230545A, CN1644581A, CN1076726C, CN1125063C, CN111111306A, CN1861594A, etc. The anion exchange resin used is a styrene-divinylbenzene polymer containing primary, secondary amine or quaternary ammonium groups. The anion exchange resin can only remove substances in ionic state in the solution. Nonionic surfactants are not ionized in water and sulfolane, so they cannot be removed by ion exchange resins. 2) Precipitation separation method, such as patent US4820849, adding polyacid or polyacid anhydride to sulfolane solvent to form solid precipitation with acidic impurities; alkali adsorption separation method, such as Japanese patents 7-278316, CN1634917A, CN106957297A, using alkali metal or alkaline earth metal oxides, hydroxides, carbonates to adsorb acidic impurities in sulfolane. These two methods can only remove acidic impurities in sulfolane, and non-ionic surfactants are not acidic substances, so these two methods cannot remove non-ionic surfactants. 3) Activated carbon adsorption method, Japanese patent 7-101953 uses activated carbon and tiny fibrous natural cellulose to remove suspended particles and dissolved ionic impurities. Activated carbon has no selectivity for the adsorption of sulfolane and non-ionic surfactants, and the selectivity ratio is less than 2. The concentration of sulfolane in the sulfolane desulfurization solution is much higher than that of non-ionic surfactants. Due to the concentration advantage, it will occupy the activated carbon adsorption surface before the non-ionic surfactants, making it quickly saturated, resulting in a non-ionic surfactant removal rate of less than 10%. 4) Decomposition method, CN213885678U decomposes part of the acidic substances of sulfolane by adding monoethanolamine. Non-ionic surfactants cannot be decomposed by monoethanolamine, so it is not applicable.

[0009] The existing purification technologies for deteriorated 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 in desulfurization solutions, such as US6517700, US5162084, US5788864, CN1733355A, CN1230545A, CN102189008A; vacuum distillation has a high sulfolane loss rate and a low removal rate of non-ionic surfactants; activated carbon adsorption separation and the foaming impurity removal technology independently developed by Southwest Oil and Gas Field Branch have no selectivity for the adsorption of sulfolane and non-ionic surfactants, and the removal rate of non-ionic surfactants is less than <10%.

[0010] At present, the treatment methods of non-ionic surfactant wastewater mainly include foam separation method, adsorption method, biological method, micro-electrolysis method, Fenton oxidation method, etc. Foam separation method is a more commonly used physical method, which separates the foam by bubbling to remove the non-ionic surfactant in the foam. This method has the advantages of easy operation and can also achieve the purpose of separating non-ionic surfactants. However, for the sulfolane desulfurization solution with severe foaming, the whole solution foams after bubbling, and after the foam separation is removed, sulfolane also loses 80 to 90 percent. For example, patent CN107935236A uses adsorbent material particles to adsorb the surfactant in the wastewater, and then bubbling allows the adsorbent material particles of the adsorbent to be enriched on the wastewater liquid surface and then removed. Adsorbent material particles include silicon dioxide, calcium carbonate, calcium sulfate, activated carbon particles, magnetite powder, hematite powder, titanium dioxide, clay ore, fly ash or phosphate tailings powder, and iron tetroxide, silicon dioxide, titanium oxide, zinc oxide metal oxide nanoparticles synthesized by wet chemistry, silicon dioxide and titanium dioxide with amino or carboxyl modified surfaces, polystyrene resin particles, phenolic resin particles or melamine resin particles, unmodified polystyrene resin particles, unmodified phenolic resin particles or unmodified melamine resin particles. These adsorbent materials have no selective absorption for sulfolane and non-ionic surfactants, and not only have a low removal rate for non-ionic surfactants in sulfolane, but also a large loss of sulfolane. Adsorption method, "Research on the Treatment of Non-ionic Surfactant Wastewater with Modified Fly Ash" introduces that fly ash is modified with hydrochloric acid, sulfuric acid and other reagents to obtain fly ash adsorption coagulant, and then the modified fly ash adsorption coagulant is used to treat wastewater containing non-ionic surfactant alkylphenol polyoxyethylene ether. The results show that the modified fly ash has good adsorption performance for wastewater containing alkylphenol polyoxyethylene ether with a concentration of 300-1800 mg / L; however, the modification process requires the addition of hydrochloric acid, sulfuric acid and other reagents, which will cause hydrochloric acid and sulfuric acid to flow into the wastewater during wastewater treatment, causing secondary pollution and increasing the difficulty of subsequent wastewater treatment. This method that causes secondary pollution is even worse for sulfolane. The introduction of hydrochloric acid and sulfuric acid into sulfolane will not only cause corrosion problems, but also cause its desulfurization performance to deteriorate or even completely fail, so it is not applicable. The biological method is a method of using microorganisms to use non-ionic surfactants as carbon sources to degrade non-ionic surfactants in wastewater. Sulfolane and other organic substances are also organic matter and will be degraded at the same time, so it is not applicable. The micro-electrolysis method is based on the principle of electrochemistry. It forms an electrode reaction in the wastewater to cause non-ionic surfactants to undergo catalytic oxidation decomposition, coagulation, adsorption, complexation and replacement reactions, thereby quickly removing pollutants. The Fenton oxidation method uses the ferrous ions in the Fenton reagent as a catalytic initiator. Under its action, H2O2 produces a large number of free radicals, which further accelerates the initiation reaction of the free radical chain, thereby quickly degrading and removing the non-ionic surfactants in the wastewater.These two methods are usually used in combination, such as patents CN110357357A, CN1508077A, CN104310665, and CN109626675A. These methods require the addition of acid to adjust the pH to 0.5-5, and then introduce iron ions and ferrous ions, which are not suitable for sulfolane because the addition of acid will reduce its desulfurization performance or even completely fail, increase its corrosiveness, and the precipitation of iron ions and ferrous ions after contact with hydrogen sulfide will cause the desulfurization device to be blocked.

[0011] In summary, the removal rate of nonionic surfactants in sulfolane by the existing technologies is very low, less than 30%, there is no selectivity for the removal of sulfolane and nonionic surfactants (selection ratio <2), the loss rate of sulfolane is high, and some technologies may introduce new impurities into the solution, causing the desulfurization performance to deteriorate and the corrosiveness to increase. Summary of the invention

[0012] An object of the present invention is to provide a nonionic surfactant removing agent and a preparation method thereof.

[0013] Another object of the present invention is to provide an application of the nonionic surfactant remover, especially in the deep removal of nonionic surfactants in sulfolane, so as to solve the problems of poor selectivity and low removal rate of nonionic surfactants in sulfolane in the prior art.

[0014] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0015] One aspect of the present invention provides a method for preparing a nonionic surfactant removing agent, wherein the preparation method comprises the following steps:

[0016] The acrylate monomer, the aliphatic diene crosslinking agent and the porogen are suspended and copolymerized in water to obtain porous polymer microspheres;

[0017] The porous polymer microspheres are added into a boric acid solution and soaked, and then the microspheres are filtered out and dried to obtain the removal agent.

[0018] The remover prepared by the present invention has high selectivity for nonionic surfactants and sulfolane, and can achieve the removal of nonionic surfactants in a desulfurization solution containing sulfolane. Specifically, the active component boric acid in the pores of the porous polymer microspheres can be complexed with the nonionic surfactant entering, but not with sulfolane, thereby achieving selective adsorption of the two, achieving deep removal of the nonionic surfactant in sulfolane, and low sulfolane loss rate; at the same time, it can be ensured that no new impurities are introduced after the nonionic surfactant in sulfolane is removed.

[0019] In some embodiments of the present invention, the structural formula of the acrylate monomer is Wherein R is a C1-C5 alkyl group, preferably, the acrylate monomer is methyl acrylate or hexyl acrylate, more preferably hexyl acrylate.

[0020] Sulfolane has a weak affinity for chain alkane molecules and a strong affinity for aromatic molecules. Therefore, the present invention does not select commonly used styrene as a monomer, but uses acrylate as a monomer. At the same time, the ester group in acrylate has a certain adsorption effect on sulfolane, but the alkyl group has a shielding effect on the effect of the ester group adsorbing sulfolane. The more carbon atoms in the alkyl group, the greater the shielding effect. However, if the number of alkyl groups is too large, a longer polyacrylate segment and a linear acrylate homopolymer may be generated during the polymerization reaction, causing the prepared remover to agglomerate during use. Among them, the number of alkyl groups in the hexyl acrylate molecule can best take into account the solution of the above two problems, satisfying that the shielding effect is large enough to have a very weak adsorption effect on sulfolane, and the remover will not agglomerate during use. Therefore, the acrylate monomer of the present invention is preferably hexyl acrylate.

[0021] In some embodiments of the present invention, preferably, the aliphatic diene crosslinking agent is ethylene glycol dimethacrylate.

[0022] The polymer stripping agent of the present invention selects aliphatic diene as a crosslinking agent, and does not select conventional phenyl-containing divinylbenzene as a crosslinking agent because phenyl can adsorb cyclopentane. The preferred ethylene glycol dimethacrylate can increase the swelling degree of the copolymer, and the interchain distance of the finally obtained polymer is conducive to the penetration of nonionic surfactants with larger molecular weight.

[0023] In some embodiments of the present invention, preferably, the porogen is selected from at least one of isooctyl alcohol, n-decane, decanol, and 2-ethyl-1-hexanoic acid.

[0024] The pore size of the micropores prepared by using isooctyl alcohol, n-decane, decanol, and 2-ethyl-1-hexanoic acid is suitable for the subsequent introduction of the active component boric acid, but the pore size is not too large to weaken the potential energy superposition effect of each plane. Other porogens will either result in a low loading amount of the active component boric acid, or lead to weak adsorption of non-ionic surfactants, resulting in a small amount of adsorbed non-ionic surfactants being resolved.

[0025] In some embodiments of the present invention, preferably, the porogen is selected from at least one of n-decane, decanol, and 2-ethyl-1-hexanoic acid.

[0026] 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).

[0027] When the amount of cross-linking agent is higher than 0.3, the internal structure of the porous polymer microspheres will be too tight, which will increase the shuttling resistance of non-ionic surfactant molecules inside the porous polymer microspheres, which is not conducive to adsorption or desorption during regeneration, and the removal rate is low. When the amount of cross-linking agent is lower than 0.07, the porous polymer microspheres will aggregate in the cyclopentane sulfone desulfurization solution. When the amount of porogen is lower than 0.1, the pore capacity and specific surface area of ​​the porous polymer microspheres are too low, and the adsorption capacity of <10 mg / g does not meet the use requirements. When the amount of porogen is higher than 0.8, the porous polymer microspheres will have problems of poor strength and collapse of the internal pore structure.

[0028] 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).

[0029] In some embodiments of the present invention, preferably, the boric acid solution is a saturated boric acid solution at 80-90°C.

[0030] High concentration boric acid solution is conducive to the loading of boric acid, but the solubility of boric acid in cold water is very low. Increasing the temperature can increase its solubility; but when the temperature reaches above 90°C, the solution has a tendency to boil, which is not conducive to the deposition of boric acid on the microspheres. Therefore, the preferred boric acid solution of the present invention is a saturated boric acid solution at 80-90°C.

[0031] In some embodiments of the present invention, preferably, the mass ratio of the boric acid to the porous polymer microspheres is greater than 0.1. Too small an amount of boric acid will result in the adsorption capacity of the obtained stripping agent for nonionic surfactants being less than 10 mg / g, which does not meet the use requirements.

[0032] In some embodiments of the present invention, more preferably, the mass ratio of the boric acid to the porous polymer microspheres is 0.7:1.

[0033] In some embodiments of the present invention, preferably, the soaking time is >0.5 h.

[0034] In some embodiments of the present invention, more preferably, the soaking time is 5 h to 6 h.

[0035] When the immersion time is less than 0.5 h, the adsorption capacity of the obtained remover for nonionic surfactant is less than 10 mg / g and does not meet the use requirements. When the immersion time exceeds 6 h, the adsorption capacity of the remover no longer continues to increase.

[0036] In some embodiments of the present invention, preferably, the immersion temperature is 50-90° C., at which 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.

[0037] In some embodiments of the present invention, preferably, the drying temperature is 100-165°C.

[0038] In some embodiments of the present invention, more preferably, the drying temperature is 120-140°C.

[0039] When the drying temperature is higher than 165°C, boric acid tends to decompose into metaboric acid. 120-140°C can ensure drying without decomposing boric acid and shorten the drying time.

[0040] Another aspect of the present invention provides a nonionic surfactant removing agent, which is obtained by any of the above preparation methods.

[0041] The stripping agent is a porous polymer microsphere with boric acid loaded in the pores; the porous polymer microsphere is polymerized by an acrylate monomer and an aliphatic diene crosslinking agent, and the pores are formed by adding a porogen during the polymerization process.

[0042] In some embodiments of the present invention, preferably, the particle size distribution of the stripping agent is 0.2 mm to 1.0 mm.

[0043] In some embodiments of the present invention, preferably, the specific surface area of ​​the stripping agent is 300m 2 / g~400m 2 / g.

[0044] In some embodiments of the present invention, preferably, the average pore size of the stripping agent is 15 nm to 27 nm.

[0045] In some embodiments of the present invention, preferably, the pore volume of the removing agent is 1.5 mL / g to 2.0 mL / g.

[0046] In another aspect, the present invention provides a use of any one of the above removing agents in removing nonionic surfactants in an organic solution.

[0047] In some embodiments of the present invention, preferably, the stripping agent is used in the removal of nonionic surfactants in sulfolane.

[0048] In some embodiments of the present invention, more preferably, the stripping agent is used in the removal of nonionic surfactants in sulfolane desulfurization solution.

[0049] In some embodiments of the present invention, preferably, the selective adsorption ratio of the stripping agent to the nonionic surfactant and sulfolane is >10, preferably >50.

[0050] In some embodiments of the present invention, the nonionic surfactant in the organic solution is preferably removed by soaking or rinsing.

[0051] In some embodiments of the present invention, it is more preferred to remove the nonionic surfactant in the organic solution by elution. Compared with the immersion method, the elution method can form a larger concentration difference, that is, the difference between the concentration of the nonionic surfactant in the solution and the concentration of the nonionic surfactant on the stripping agent, so the removal rate is higher.

[0052] In some embodiments of the present invention, preferably, the operating parameters for removing the nonionic surfactant from the organic solution by elution include: normal temperature and pressure, and the flow rate of the organic solution elution removal agent is less than 20 BV / h.

[0053] In some embodiments of the present invention, more preferably, the flow rate of the organic solution eluting the stripping agent is 4 BV / h to 6 BV / h.

[0054] The volume of resin loaded in the resin column is called bed volume, abbreviated as BV. If the flow rate of the solution through the resin column is 2BV / h~4BV / h, the volume of the solution passing through the resin column per hour is 2~4 times the volume of the resin bed. It takes a certain amount of time for the non-ionic surfactant in the solution to be adsorbed onto the stripping agent. If the flow rate is too fast, that is, when it reaches 20BV / h or above, the removal rate is less than 60%.

[0055] In some embodiments of the present invention, preferably, after the stripping agent is saturated with the nonionic surfactant, it is regenerated with a weakly polar or medium-polar organic solvent.

[0056] The interaction force between the nonionic surfactant molecules and the weakly polar or medium-polar organic solvent molecules is stronger than the interaction force between the nonionic surfactant molecules and the boric acid. The nonionic surfactant molecules can be separated from the boric acid to desorb and regenerate the removal agent.

[0057] In some embodiments of the present invention, more preferably, the weakly polar or medium-polar organic solvent is dichloromethane and / or ethyl acetate.

[0058] The beneficial effects of the present invention include:

[0059] 1) The desorbent of the present invention has high selectivity for the adsorption of nonionic surfactants and sulfolane, and the selectivity ratio of nonionic surfactants and sulfolane can reach >50, while the selectivity ratio of the prior art is <2;

[0060] 2) The removal rate of the desorbent of the present invention for the nonionic surfactant in the sulfolane solution is ≥98%, while the removal rate of the prior art is <30%;

[0061] 3) When the desorbent of the present invention is used to remove the nonionic surfactant in the sulfolane solution, the sulfolane loss rate is less than 1%;

[0062] 4) When the desorbent of the present invention is used to purify the deteriorated sulfolane desulfurization solution, no other reagents need to be added and impurities will not be introduced into the desulfurization solution.

[0063] The desorbent of the present invention can efficiently remove the foaming substances in the sulfolane desulfurization solution, and avoid the problems of unqualified product natural gas quality, unstable device operation, and shutdown caused by the contamination and foaming of the desulfurization solution in the natural gas purification plant. In addition, before the successful development of the technical solution of the present invention, due to the lack of technology that can effectively remove the foaming substances in the sulfolane desulfurization solution, the sulfolane desulfurization solution of the purification plant could not be used after being contaminated, and could only be replaced with a new solvent. The contaminated solution replaced out of the device was treated as waste liquid. The waste liquid generated by only one set of desulfurization equipment due to contamination is usually as high as more than 400 tons. Because the organic content of the sulfolane desulfurization solution is as high as 70% or more, and it also contains toxic components such as hydrogen sulfide, the difficulty and cost of disposal are very large, which has caused great economic burden and environmental pressure on the purification plant. The results of the present invention restore the performance of the deteriorated sulfolane that could only be used as waste liquid in the past, and continue to use it, which not only ensures normal production, but also solves the problems of solvent consumption and waste liquid disposal, significantly reduces the production cost and environmental pressure of the purification plant, and has excellent economic and social benefits. DETAILED DESCRIPTION

[0064] In order to explain the present invention more clearly, the present invention is further described below in conjunction with preferred embodiments. It should be understood by those skilled in the art that the following specific description is illustrative rather than restrictive, and should not be used to limit the scope of protection of the present invention.

[0065] The key to the technical solution of the present invention lies in the design and preparation of a non-ionic surfactant removing agent, wherein the removing agent is a porous polymer microsphere with boric acid loaded in the pores; the porous polymer microsphere is prepared by suspension copolymerization of an acrylate monomer and an aliphatic diene crosslinking agent, and a porogen is also added during the polymerization process to form the pores.

[0066] The remover of the present invention has high selectivity for nonionic surfactants and sulfolane, and can achieve the removal of nonionic surfactants in a desulfurization solution containing sulfolane. Specifically, the active component boric acid in the pores of the porous polymer microspheres can be complexed with the nonionic surfactant entering, but not with sulfolane, thereby achieving selective adsorption of the two, achieving deep removal of the nonionic surfactant in sulfolane, and low sulfolane loss rate; at the same time, it can be ensured that no new impurities are introduced after the nonionic surfactant in sulfolane is removed.

[0067] Conventional polymer adsorbents are polymers formed by using styrene as a monomer and divinylbenzene as a crosslinking agent. Since sulfolane has a strong affinity for phenyl, this type of adsorbent has a strong adsorption effect on sulfolane. The stripping agent of the present invention is a polymer prepared by using acrylate as a monomer and aliphatic diene as a crosslinking agent, and neither the monomer nor the crosslinking agent contains phenyl.

[0068] Sulfolane has a weak affinity for chain alkane molecules and a strong affinity for aromatic molecules. Therefore, the present invention does not select commonly used styrene as a monomer, but uses acrylate as a monomer. At the same time, the ester group in the acrylate has a certain adsorption effect on sulfolane, but the alkyl group has a shielding effect on the effect of the ester group adsorbing sulfolane. The more carbon atoms in the alkyl group, the greater the shielding effect. However, if the number of alkyl groups is too large, a longer polyacrylate segment and a linear acrylate homopolymer may be generated during the polymerization reaction, causing the prepared remover to agglomerate during use. The present invention preferably uses acrylates of C1-C5 alcohols, such as methyl acrylate and hexyl acrylate. Among them, the number of alkyl groups in the hexyl acrylate molecule can best take into account the solution of the above two problems, satisfying that the shielding effect is large enough to have a very weak adsorption effect on sulfolane, and the remover will not agglomerate during use. Therefore, the acrylate monomer of the present invention is most preferably hexyl acrylate.

[0069] The polymer stripping agent of the present invention selects aliphatic diene as a crosslinking agent, and does not select conventional phenyl-containing divinylbenzene as a crosslinking agent because phenyl can adsorb cyclopentane. The preferred ethylene glycol dimethacrylate can increase the swelling degree of the copolymer, and the interchain distance of the finally obtained polymer is conducive to the penetration of nonionic surfactants with larger molecular weight.

[0070] The micropores prepared by the porogens preferably used in the present invention, such as isooctyl alcohol, n-decane, decanol, and 2-ethyl-1-hexanoic acid, have a pore size suitable for the subsequent introduction of the active component boric acid, while not making the pores too large to weaken the potential energy superposition effect of each plane. Other porogens either result in a lower loading amount of the active component boric acid or lead to weak adsorption of the non-ionic surfactant, resulting in the problem of a small amount of adsorbed non-ionic surfactant being resolved.

[0071] When preparing the porous polymer microspheres, the molar ratio of the acrylate monomer, the aliphatic diene crosslinker, and the porogen is preferably 1: (0.07-0.3): (0.1-0.8). When the amount of the crosslinker is higher than 0.3, the internal structure of the porous polymer microspheres obtained will be too tight, which will increase the resistance of the non-ionic surfactant molecules to shuttle inside the porous polymer microspheres, which is not conducive to adsorption or desorption during regeneration, and the removal rate is low. When the amount of the crosslinker is lower than 0.07, the porous polymer microspheres obtained will aggregate in the cyclopentane sulfone desulfurization solution. When the amount of the porogen is lower than 0.1, the pore capacity and specific surface area of ​​the porous polymer microspheres obtained are too low, and the adsorption capacity <10 mg / g does not meet the use requirements. When the amount of the porogen is higher than 0.8, the porous polymer microspheres will have problems of poor strength and collapse of the internal pore structure. More preferably, the molar ratio of the acrylic acid ester monomer, the aliphatic diene crosslinking agent, and the porogen is preferably 1:(0.1-0.2):(0.5-0.6).

[0072] The particle size distribution of the desorbent prepared by the present invention is preferably 0.2 mm to 1.0 mm; the specific surface area is preferably 300 m 2 / g~400m 2 / g; the average pore diameter is preferably 15nm~27nm; the pore volume is preferably 1.5mL / g~2.0mL / g.

[0073] The specific preparation method of the removing agent comprises the following steps:

[0074] The acrylate monomer, the aliphatic diene crosslinking agent and the porogen are suspended and copolymerized in water to obtain porous polymer microspheres;

[0075] The porous polymer microspheres are added into a boric acid solution and soaked, and then the microspheres are filtered out and dried to obtain the removal agent.

[0076] In some specific embodiments, the boric acid solution is preferably a saturated boric acid solution at 80-90°C. High-concentration boric acid solution is conducive to the loading of boric acid, but the solubility of boric acid in cold water is very low. Increasing the temperature can increase its solubility; but when the temperature reaches above 90°C, the solution has a tendency to boil, which is not conducive to the deposition of boric acid on the microspheres. Therefore, the preferred boric acid solution of the present invention is a saturated boric acid solution at 80-90°C.

[0077] In some specific embodiments, the mass ratio of the boric acid to the porous polymer microspheres is greater than 0.1. Too little boric acid will result in the adsorption capacity of the obtained stripping agent for nonionic surfactants being less than 10 mg / g, which does not meet the use requirements. More preferably, the mass ratio of the boric acid to the porous polymer microspheres is 0.7.

[0078] In some specific embodiments, the soaking time is greater than 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 obtained remover for nonionic surfactant is less than 10 mg / g, which does not meet the use requirements. After the soaking time exceeds 6 h, the adsorption capacity of the remover no longer increases.

[0079] In some specific embodiments, the immersion temperature is 50-90° C. At this temperature, the solubility of boric acid is high. When the temperature is higher than 90° C., the solution tends to boil, which is not conducive to the deposition of boric acid on the microspheres.

[0080] In some specific embodiments, the drying temperature is 100-165° C., more preferably 120-140° C. When the drying temperature is higher than 165° C., boric acid tends to decompose into metaboric acid. 120-140° C. can ensure drying without decomposing boric acid and shorten the drying time.

[0081] In some specific embodiments, initiators, dispersants, etc. are usually added during the suspension copolymerization process, such as benzoyl peroxide and hydroxyethyl cellulose in the embodiments, and the added amount is sufficient to initiate polymerization and disperse the agent, which is not limited in the present invention.

[0082] The above-mentioned removal agent of the present invention can be specifically applied to the removal of nonionic surfactants in organic solutions; in particular, the removal of nonionic surfactants in sulfolane. More specifically, it can be applied to the removal of nonionic surfactants in sulfolane desulfurization solutions. The removal agent can achieve a selective absorption ratio of nonionic surfactants and sulfolane greater than 50.

[0083] In some specific embodiments, the nonionic surfactant in the organic solution is removed by soaking or rinsing. More preferably, the nonionic surfactant in the organic solution is removed by rinsing. Compared with the soaking method, the rinsing method can form a larger concentration difference, that is, the difference between the concentration of the nonionic surfactant in the solution and the concentration of the nonionic surfactant on the stripping agent, so the removal rate is higher.

[0084] In some specific embodiments, the operating parameters for removing the nonionic surfactant from the organic solution by elution include: normal temperature and pressure, and the flow rate of the organic solution elution removal agent is less than 20 BV / h. More preferably, the flow rate of the organic solution elution removal agent is 4 BV / h to 6 BV / h.

[0085] The volume of resin loaded in the resin column is called bed volume, abbreviated as BV. If the flow rate of the solution through the resin column is 2BV / h~4BV / h, the volume of the solution passing through the resin column per hour is 2~4 times the volume of the resin bed. It takes a certain amount of time for the non-ionic surfactant in the solution to be adsorbed onto the stripping agent. If the flow rate is too fast, that is, when it reaches 20BV / h or above, the removal rate is less than 60%.

[0086] In addition, after the removal agent is saturated with the nonionic surfactant, it can also be regenerated with a weak polar or medium polar organic solvent. The interaction force between the nonionic surfactant molecules and the weak polar or medium polar organic solvent molecules is stronger than the interaction force between the nonionic surfactant molecules and the boric acid, so the nonionic surfactant molecules can be separated from the boric acid to desorb and regenerate the removal agent. Preferably, the weak polar or medium polar organic solvent is dichloromethane and / or ethyl acetate.

[0087] In a preferred embodiment of the present invention, the acrylic acid ester monomer is hexyl acrylate, the aliphatic diene crosslinking agent is ethylene glycol dimethacrylate, and the porogen is decane, decanol or 2-ethyl-1-hexanoic acid.

[0088] Conventional polymer adsorbents are polymers formed with styrene as a monomer and divinylbenzene as a crosslinking agent. Since sulfolane has a strong affinity for phenyl, this type of adsorbent has a strong adsorption effect on sulfolane. The stripping agent of the present invention is a polymer prepared with acrylate as a monomer and aliphatic diene as a crosslinking agent, and neither the monomer nor the crosslinking agent contains phenyl. The ester group in acrylate has a certain adsorption effect on sulfolane, but the alkyl group has a shielding effect on the adsorption of sulfolane by the ester group, and the more carbon atoms in the alkyl group, the greater the shielding effect; however, if the number of alkyl groups is too large, a longer polyacrylate chain segment and a linear acrylate homopolymer may be generated during the polymerization reaction, causing the prepared stripping agent to clump during use. The number of alkyl groups in the hexyl acrylate molecule can solve the above two problems at the same time, satisfying that the shielding effect is large enough to have a weak adsorption effect on sulfolane, and the stripping agent will not clump during use. The preferred ethylene glycol dimethacrylate of cross-linking agent can increase the swelling degree of copolymer, and the interchain distance of the polymer obtained at last is large, which is not only conducive to the infiltration of organic substances with larger molecular weight of surfactant, but also the long-chain hydrocarbon group can further weaken the affinity of polymer to sulfolane and strengthen the affinity of polymer to non-ionic surfactant.Porosity-forming agent is used to make polymer into porous structure, so that surfactant molecule is located in pore, each plane in the gap acts simultaneously, potential energy produces superposition, and can strengthen the force between surfactant and stripping agent.Porosity-forming agent selects decane, decanol, 2-ethyl-1-hexanoic acid, so that the pore size of prepared porous polymer is suitable for subsequent active component introduction into pore, and the potential energy superposition effect of each plane is not too large to weaken.Boric acid is introduced and loaded on the surface of the inner hole of prepared porous polymer, because boric acid is an electron-deficient compound, and the oxygen on the polyoxyethylene of non-ionic surfactant can provide electrons to be complexed with the boron atom on boric acid, and sulfolane cannot be complexed with it, so the selective adsorption of non-ionic surfactant in sulfolane is realized.

[0089] The present invention provides some specific examples below to illustrate the present invention in more detail, wherein all numerical values ​​specified (such as temperature, time, concentration and weight, etc., including the range of each thereof) are usually appropriately changed by (+) or (-) approximate values ​​in increments of 0.1 or 1.0. All numerical values ​​specified can be understood as being preceded by the term "about".

[0090] Examples 1-13

[0091] Examples 1-13: Removers 1 to 13 were prepared according to the following steps and their performance was tested.

[0092] 1. Preparation of the remover

[0093] 1) mixing a monomer, a cross-linking agent and a porogen in a molar ratio of 1:0.1:0.5 to obtain a mixture 1;

[0094] 2) mixing mixture 1 with benzoyl peroxide in a mass ratio of 100:1 to obtain mixture 2;

[0095] 3) mixing hydroxyethyl cellulose, sodium chloride and water in a mass ratio of 0.6:10:100 to obtain a mixture 3;

[0096] 4) Mix mixture 2 and mixture 3 at a ratio of 1:3, start the stirrer, heat to 60-90°C for 12 hours, filter out the microspheres, wash with anhydrous ethanol and deionized water for 4 times, and finally dry under vacuum at 60°C for 18 hours;

[0097] 5) Transfer the microspheres to a saturated boric acid solution at 70°C (the mass ratio of the boric acid solution to the microspheres is 4.2:1, the boric acid concentration of the saturated boric acid solution at 70°C is 16.7%, and the mass ratio of boric acid to the microspheres is 0.7:1) and soak for 5 hours. Filter the microspheres and bake at 130°C for 5 hours to obtain a remover.

[0098] Follow the above steps to obtain:

[0099] Remover 1: The monomer, cross-linking agent and porogen used are hexyl acrylate, ethylene glycol dimethacrylate and 2-ethyl-1-hexanoic acid, respectively.

[0100] Remover 2: The monomer, cross-linking agent and porogen used are methyl acrylate, ethylene glycol dimethacrylate and 2-ethyl-1-hexanoic acid, respectively.

[0101] Remover 3: The monomer, cross-linking agent and porogen used are styrene, ethylene glycol dimethacrylate and 2-ethyl-1-hexanoic acid, respectively.

[0102] Remover 4: The monomer, cross-linking agent and porogen used are hexyl acrylate, divinylbenzene and 2-ethyl-1-hexanoic acid, respectively.

[0103] Stripper 5: The monomers, crosslinking agent and porogen used are the same as those of Stripper 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.

[0104] Remover 6: The monomer, cross-linking agent and porogen used are hexyl acrylate, ethylene glycol dimethacrylate and isooctyl alcohol, respectively.

[0105] Remover 7: The monomer, crosslinker and porogen used are the same as those of 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.

[0106] Remover 8: Step 5) The mass ratio of boric acid to microspheres was changed to 0.05:1.

[0107] Remover 9: Step 5) The immersion time of the microspheres in the 70°C boric acid solution was changed to 0.4 hours.

[0108] Remover 10: Step 5) Change the drying temperature of the microspheres to 166°C.

[0109] Remover 11: The monomer, cross-linking agent and porogen used are hexyl acrylate, ethylene glycol dimethacrylate and n-decane, respectively.

[0110] Remover 12: The monomer, cross-linking agent and porogen used are hexyl acrylate, ethylene glycol dimethacrylate and decanol, respectively.

[0111] Remover 13: The monomer and cross-linking agent used are hexyl acrylate and ethylene glycol dimethacrylate, respectively, and there is no porogen.

[0112] 2. Preparation of Sulfolane Solution

[0113] The most common nonionic surfactant in the natural gas desulfurization solution 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.

[0114] 3. Remover performance test

[0115] The removers 1 to 13 and activated carbon were loaded into 14 glass columns with an inner diameter of 25 mm, and the loading amount was 25 g. More than 500 g of the prepared sulfolane solution was injected into the top of each of the 14 glass columns, and the solution was allowed to flow through the activated carbon or each remover from top to bottom at a speed of 4 BV / h. Finally, nitrogen was used to blow the activated carbon and the remover from the upper end of the glass column, and the sulfolane solution flowing out of the lower end of each glass column was collected and weighed m, and the mass fraction w of polyoxyethylene alkyl alcohol ether-20 in the sulfolane solution was determined. The removal rate and selective absorption ratio of activated carbon and each remover to non-ionic surfactants were calculated as follows:

[0116] Removal rate of nonionic surfactant = (0.4% × 500 – w × m) ÷ (0.4% × 500)

[0117] Use 100 mL of ethyl acetate to elute the activated carbon and each removing agent from top to bottom, respectively elute the polyoxyethylene alkyl alcohol ether-20 and cyclopentane sulfone adsorbed on the activated carbon and each removing agent, and determine the respective masses of the two substances (the mass of the eluent multiplied by the respective contents of the two substances in the eluent).

[0118] Selective absorption ratio = the amount of polyoxyethylene alkyl alcohol ether-20 eluted / the amount of sulfolane eluted

[0119] The removal rates and selective adsorption ratios of activated carbon and various removal agents for nonionic surfactants are shown in Table 1.

[0120] Table 1 Removal rate and selective absorption ratio of each remover for nonionic surfactant

[0121]

[0122]

[0123] The experimental results shown in Table 1 show that the removers 3 and 4 made of phenyl-containing monomers or cross-linking agents not only have a selective adsorption ratio lower than 2, but also have a non-ionic surfactant removal rate of <60%; the remover 5 made with a molar ratio of cross-linking agent to monomer greater than 0.3 has selective adsorption for non-ionic surfactants in sulfolane, with a selective adsorption ratio of 33.5, much greater than 2, but a removal rate of <60%; the removers 7, 8, and 9 made with a mass ratio of porogen to monomer lower than 0.1, a mass ratio of boric acid to microspheres lower than 0.1, and a boric acid soaking time of less than 0.5 hours have very low removal rates of <20% because of their adsorption capacity <10 mg / g; the remover 10 made with the microsphere drying temperature changed to 166°C has a low removal rate of <40% because boric acid decomposes into metaboric acid.

[0124] The removal rate of the stripper 2 prepared by using methyl acrylate as the monomer can reach more than 90%, and the selective absorption ratio is greater than 10 (the loss rate of cyclopentane is less than 1%), which meets the requirements of actual production and use, but the selective absorption ratio of the stripper prepared by the most preferred monomer hexyl acrylate is higher than 50. The stripper 6 prepared by using isooctyl alcohol as the porogen has a selective absorption ratio of 47.5 and a relatively high removal rate of more than 80%, which meets the requirements of actual production and use, but the removal rate of the stripper prepared by the preferred porogens n-decane, decanol, and 2-ethyl-1-hexanoic acid is higher than 95%. The stripper 1 prepared by the most preferred conditions has very outstanding performance, with a removal rate higher than 98% and a selective absorption ratio of more than 56.

[0125] The particle size, specific surface area, average pore size and pore volume of the removers 1, 2, 6, 11 and 12 that meet the actual production requirements were measured by sieving method, respectively. The measurement results are shown in Table 2.

[0126] Table 2

[0127]

[0128] The test results shown in Table 2 show that the particle size distribution of the remover prepared under the optimal conditions is (0.2-1.0) mm; the specific surface area is (300-400) m 2 / g; the average pore diameter is (15~27)nm, and the pore volume is in the range of (1.5~2.0)mL / g.

[0129] Embodiment 14

[0130] This example explores the removal effect of the remover 1 on the non-ionic surfactant at different flow rates.

[0131] The remover 1 was loaded into 6 glass columns with an inner diameter of 25 mm, and the loading amount was 25 g. The 6 glass columns were numbered 1 # ~6 # 500 g of sulfolane solution containing 0.4% (mass fraction) of polyoxyethylene alkyl alcohol ether-20 was injected into the top of each of the six glass columns, and the solution was allowed to flow through each glass column from top to bottom at a certain flow rate. # ~6 # The flow rates are 0.1BV / h, 2BV / h, 4BV / h, 6BV / h, 7BV / h, and 20BV / h, and finally, nitrogen is used to blow activated carbon and the remover from the upper end of the glass column. The sulfolane solution flowing out of the lower end of each glass column is collected and weighed m, and the mass fraction w of polyoxyethylene alkyl alcohol ether-20 in the sulfolane solution is determined. The removal rate and selective absorption ratio of the remover to the non-ionic surfactant are calculated as follows:

[0132] Removal rate of nonionic surfactant = (0.4% × 500 – w × m) ÷ (0.4% × 500)

[0133] The removal rate of nonionic surfactant by remover 1 at different flow rates is shown in Table 3.

[0134] Table 3 Removal rate of nonionic surfactant by remover 1 at different flow rates

[0135] <![CDATA[1 # Pillar]]> <![CDATA[2 # Pillar]]> <![CDATA[3 # Pillar]]> <![CDATA[4 # Pillar]]> <![CDATA[5 # Pillar]]> <![CDATA[6 # Pillar]]> Solution flow rate 0.1BV / 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％

[0136] The experimental results shown in Table 3 show that the removal rate when the solution flow rate is 4BV / h to 6BV / h is basically the same as that when the flow rate is 2BV / h, both of which can reach more than 98%. A faster flow rate is beneficial to saving solution treatment time, so it is better; but when the flow rate is too fast, the removal rate will be reduced due to insufficient contact time. When the solution increases to 7BV / h, the removal rate decreases to 93.2%. When it increases to 20BV / h, the removal rate is less than 60%. When the flow rate is too low at 0.1BV / h, which is close to the immersion method, the removal rate is not high enough, less than 85%, so it is preferred to treat the solution by 4BV / h to 6BV / h elution removal agent.

[0137] Embodiment 15

[0138] This example uses different regeneration liquids to regenerate the stripping agent, and verifies the removal effect of the stripping agent on the non-ionic surfactant after regeneration.

[0139] 1) 2 in Example 14 # Column, 3 #Column, 4 # After the columns were regenerated by eluting with 100 ml of ethanol, dichloromethane and ethyl acetate respectively, 500 g of sulfolane solution containing 0.4% (mass fraction) of polyoxyethylene alkyl alcohol ether-20 was injected into the top of the two glass columns respectively. The solution flow rate was 4 BV / h. The removal rate of the non-ionic surfactant by the remover 1 after regeneration with ethanol, dichloromethane and ethyl acetate was tested. The test results are shown in Table 4.

[0140] Table 4 Removal rate of nonionic surfactant by remover 1 after regeneration with different regeneration solutions

[0141] <![CDATA[2 # Pillar]]> <![CDATA[3 # Pillar]]> <![CDATA[4 # Pillar]]> Regeneration fluid Ethanol Dichloromethane Ethyl acetate Removal rate 56.8％ 98.3％ 98.2％

[0142] The experimental results shown in Table 4 show that after using ethanol to regenerate the removal agent 1, its removal rate dropped significantly to below 60%; using dichloromethane and ethyl acetate to regenerate the removal agent 1, its removal rate can be maintained above 98%.

[0143] 2) Continue to elute and regenerate column 3# and column 4# with 100 ml of dichloromethane and ethyl acetate respectively, then inject 500 g of sulfolane solution containing 0.4% (mass fraction) of polyoxyethylene alkyl alcohol ether-20 at the top of the two glass columns respectively, and the solution flow rate is 4 BV / h. Repeat the above operation to test the removal rate of the remover 1 after multiple regenerations, and the measurement results are shown in Table 5.

[0144] Table 5 Removal rate of nonionic surfactant after multiple regeneration of remover 1

[0145]

[0146] The experimental results shown in Table 5 show that when the remover 1 is used to remove nonionic surfactants in sulfolane solution, the removal rate can be maintained at more than 98% of the initial removal rate after more than 100 saturation and regeneration cycles, and the stability is good.

[0147] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the protection scope of the present invention.

Claims

1. A method for preparing a nonionic surfactant removing agent, wherein: The preparation method comprises the following steps: The acrylate monomer, the aliphatic diene crosslinking agent and the porogen are suspended and copolymerized in water to obtain porous polymer microspheres; The porous polymer microspheres are added into a boric acid solution and soaked, and then the microspheres are filtered out and dried to obtain the removal agent.

2. The preparation method according to claim 1, wherein The structural formula of the acrylate monomer is: Wherein R is a C1-C5 alkyl group.

3. The preparation method according to claim 1, wherein The acrylic acid ester monomer is methyl acrylate or hexyl acrylate.

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 porogen is selected from at least one of isooctyl alcohol, n-decane, decanol, and 2-ethyl-1-hexanoic acid.

6. The preparation method according to claim 1, wherein The molar ratio of the acrylic acid ester monomer, the aliphatic diene crosslinking agent and the porogen is 1:(0.07-0.3):(0.1-0.8).

7. The preparation method according to claim 1, wherein The boric acid solution is a saturated boric acid solution at 80-90°C.

8. The preparation method according to claim 1, wherein The mass ratio of the boric acid to the porous polymer microspheres is greater than 0.

1.

9. The preparation method according to claim 1, wherein The soaking time is greater than 0.5 h, and the soaking temperature is 50-90° C.

10. The preparation method according to claim 1, wherein: The drying temperature is 100-165°C.

11. A nonionic surfactant removing agent obtained by the preparation method according to any one of claims 1 to 10.

12. The removing agent according to claim 11, wherein The particle size distribution of the remover is 0.2 mm to 1.0 mm.

13. The nonionic surfactant removing agent according to claim 11, wherein The specific surface area of ​​the descavenger is 300m 2 / g~400m 2 / g.

14. The nonionic surfactant removing agent according to claim 11, wherein The average pore size of the remover is 15nm to 27nm.

15. The nonionic surfactant removing agent according to claim 11, wherein The pore volume of the removing agent is 1.5 mL / g to 2.0 mL / g.

16. Use of the removing agent according to any one of claims 11 to 15 in removing nonionic surfactants in organic solutions.

17. The use according to claim 16, wherein: Removing nonionic surfactants from organic solutions by soaking or leaching; The operating parameters for removing the nonionic surfactant from the organic solution by elution include: normal temperature and pressure, and the flow rate of the organic solution elution removal agent is less than 20 BV / h.

18. The use according to claim 17, wherein: The flow rate of the organic solution eluting remover is 4BV / h to 6BV / h.

19. The use according to claim 17, wherein: After the stripping agent is saturated with the nonionic surfactant, it is regenerated with a weak polar or medium polar organic solvent.

20. The use according to claim 19, wherein: The weakly polar or medium polar organic solvent is dichloromethane and / or ethyl acetate.

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