Phenolic resin microspheres as well as preparation method and application thereof
By controlling the molar ratio of phenolic compounds and aldehyde compounds, phenolic resin microspheres were prepared, solving the problem of poor selective adsorption of aluminum ions by phenolic resin and achieving efficient and low-loss aluminum ion recovery.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-13
- Publication Date
- 2026-03-10
AI Technical Summary
In existing technologies, phenolic resins have poor selective adsorption of aluminum ions when recycling waste lithium-ion batteries, and are prone to introducing new impurities, resulting in high metal loss rates, complex processes, and high costs.
Phenolic resin microspheres were prepared by controlling the molar ratio of phenolic compounds and aldehyde compounds through polycondensation and curing reactions. Combined with an oil phase and an emulsifier, phenolic resin microspheres with selective adsorption properties were prepared.
This method achieves highly efficient and selective adsorption of aluminum ions in lithium iron phosphate leaching solution, reduces the adsorption rate of iron ions, minimizes metal loss, and simplifies the process.
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Abstract
Description
Technical Field
[0001] This application relates to the field of resin materials technology, and in particular to a phenolic resin microsphere, its preparation method, and its application. Background Technology
[0002] Aluminum removal is a crucial step in the industrial and chemical processes of recycling spent lithium-ion batteries. Currently, aluminum removal methods typically employ chemical precipitation (such as pH-adjusted hydrolysis precipitation), where the pH of the solution is adjusted to the precipitation range for aluminum (pH 4-6, forming Al(OH)3 precipitate) by adding alkali (such as NaOH, Ca(OH)2, NH4OH). However, chemical precipitation methods suffer from poor selectivity, the introduction of new impurities, the risk of loss of recyclable metals, and the high cost and complexity of solvent extraction methods. Therefore, there is an urgent need to develop an aluminum removal method that offers high selectivity, low loss of recyclable metals, simple processing, and avoids the introduction of new impurities.
[0003] Phenolic resin, as an adsorbent material with strong acid and alkali resistance, can avoid introducing new impurities when used in the recycling of waste lithium-ion batteries. However, its adsorption selectivity varies greatly, and it cannot selectively adsorb aluminum ions in lithium iron phosphate acid leaching solutions. Therefore, how to provide a phenolic resin that can selectively adsorb aluminum ions has become an urgent technical problem to be solved. Summary of the Invention
[0004] Therefore, the main objective of this application is to provide a phenolic resin microsphere, its preparation method, and its application, so as to achieve selective adsorption of aluminum ions and iron ions.
[0005] The first aspect of this application provides a method for preparing phenolic resin microspheres, comprising the following steps:
[0006] A prepolymer is prepared by mixing phenolic compounds, aldehyde compounds, and acid catalysts and carrying out a polycondensation reaction.
[0007] The prepolymer was mixed with an oil phase and an emulsifier, and a curing reaction was carried out to prepare phenolic resin microspheres.
[0008] The phenolic compounds include phenol and other phenolic compounds in a molar ratio of 0.5-2:1.
[0009] In some embodiments, the other phenolic compounds include at least one of salicylic acid, aminosalicylic acid, sulfosalicylic acid, catechol, pyrogallol, and 8-hydroxyquinoline.
[0010] In some embodiments, the aldehyde compounds include formaldehyde and other aldehyde compounds;
[0011] The other aldehyde compounds include at least one of acetaldehyde, hydroxyacetaldehyde, acrolein, and glyceraldehyde.
[0012] In some embodiments, the molar ratio of formaldehyde to the other aldehyde compounds is 1-3:1.
[0013] In some embodiments, the acid catalyst includes hydrochloric acid and / or sulfuric acid.
[0014] In some embodiments, the molar ratio of the acid catalyst to the phenolic compound is 0.1-1:100; the molar ratio of the phenolic compound to the aldehyde compound is 1-4:1.
[0015] In some embodiments, the conditions for the polycondensation reaction include: a temperature of 60-90°C and a time of 1-3 hours;
[0016] The curing reaction conditions include a temperature of 70-100°C. In some embodiments, the oil phase includes at least one of liquid paraffin, cyclohexane, and toluene.
[0017] The emulsifier includes Span 80;
[0018] The mass ratio of the emulsifier to the oil phase is 1-10:100.
[0019] In a second aspect of this application, phenolic resin microspheres prepared by the preparation method described in the first aspect are provided.
[0020] In a third aspect of this application, the application of phenolic resin microspheres prepared by the preparation method described in the first aspect or the phenolic resin microspheres described in the second aspect in the adsorption of aluminum ions is provided.
[0021] Compared with traditional technologies, this application has at least the following beneficial effects:
[0022] This application describes a process for preparing phenolic resin microspheres by performing a polycondensation reaction on a mixture of phenol, other phenolic compounds, aldehydes, and an acid catalyst. The prepolymer is then mixed with an oil phase and an emulsifier, followed by a curing reaction. The preparation process is simple and pollution-free. Furthermore, by controlling the molar ratio of phenol to other phenolic compounds, the prepared phenolic resin microspheres exhibit excellent selective adsorption properties, enabling specific adsorption of aluminum ions from aluminum-iron wastewater, particularly in lithium iron phosphate leaching solutions with a high iron-to-aluminum ratio, thus reducing the adsorption rate of iron ions. Detailed Implementation
[0023] The present application will be further described in detail below with reference to the embodiments and examples. These embodiments and examples are only for illustrating the present application and are not intended to limit the scope of the present application. The purpose of providing these embodiments and examples is to make the disclosure of the present application more thorough and comprehensive. It should also be understood that the present application can be implemented in many different forms and is not limited to the embodiments and examples described herein. Those skilled in the art can make various modifications or alterations without departing from the spirit of the present application, and the equivalent forms obtained also fall within the protection scope of the present application. In addition, numerous specific details are set forth in the following description to provide a fuller understanding of the present application. It should be understood that the present application can be implemented without one or more of these details.
[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.
[0025] As used herein, the term "and / or" includes any and all combinations of one or more of the related listed items.
[0026] The "range" disclosed in this application can be defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of the specific range. Ranges defined in this way can include or exclude endpoints. Any endpoint can be independently included or excluded, and they can be combined arbitrarily; that is, any lower limit can be combined with any upper limit to form a range. For example, if a range of 0.5-2:1 is listed for a specific parameter, it is expected that ranges of 0.5-1:1 and 1-2:1 are also included. In this application, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0.5-2:1" means that all real numbers between "0.5-2:1" have been listed herein; "0.5-2:1" is merely a shortened representation of these numerical combinations.
[0027] To address the problem that current phenolic resins have low adsorption capacity and significant differences in adsorption selectivity, making it impossible to selectively adsorb aluminum ions from lithium iron phosphate leaching solutions, this application proposes a method to prepare a prepolymer by mixing phenol, other phenolic compounds, aldehydes, and an acid catalyst and subjecting them to a condensation reaction. The prepolymer is then mixed with an oil phase and an emulsifier, followed by a curing reaction to prepare phenolic resin microspheres. Furthermore, by controlling the molar ratio of phenol to other phenolic compounds, the prepared phenolic resin microspheres can achieve specific adsorption of aluminum ions from lithium iron phosphate leaching solutions with a high adsorption rate, while exhibiting a low adsorption rate for iron ions, thus reducing iron ion loss.
[0028] The first aspect of this application provides a method for preparing phenolic resin microspheres, comprising the following steps:
[0029] A prepolymer is prepared by mixing phenolic compounds, aldehyde compounds, and acid catalysts and carrying out a polycondensation reaction.
[0030] The prepolymer was mixed with an oil phase and an emulsifier, and a curing reaction was carried out to prepare phenolic resin microspheres.
[0031] The phenolic compounds include phenol and other phenolic compounds in a molar ratio of 0.5-2:1. In some embodiments, the other phenolic compounds include at least one selected from salicylic acid, aminosalicylic acid, sulfosalicylic acid, catechol, pyrogallol, and 8-hydroxyquinoline.
[0032] This application uses phenol and other phenolic compounds as phenolic compounds to prepare phenolic resin microspheres. The phenolic resin microspheres can achieve specific adsorption of aluminum ions, improve the adsorption rate of aluminum ions, and at the same time reduce the risk of loss of recyclable iron ions.
[0033] In some embodiments, the molar ratio of phenol to the other phenolic compounds is 0.5-2:1, which can be 0.5:1, 1:1, 3:2 or 2:1.
[0034] In some embodiments, the molar ratio of the acid catalyst to the phenolic compound is 0.1-1:100, and can be 0.1:100, 0.2:100, 0.3:100, 0.4:100, 0.5:100, 0.6:100, 0.7:100, 0.8:100, 0.9:100, or 1:100;
[0035] The molar ratio of the phenolic compound and the aldehyde compound is 1-4:1, and can be 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.3:1 or 4:1.
[0036] In some embodiments, the aldehyde compounds include formaldehyde and other aldehyde compounds;
[0037] The other aldehyde compounds include at least one of acetaldehyde, hydroxyacetaldehyde, acrolein, and glyceraldehyde.
[0038] In some embodiments, the molar ratio of formaldehyde to the other aldehyde compounds is 1-3:1, which can be 1:1, 3:2, 2:1, 5:2 or 3:1.
[0039] In some embodiments, the acid catalyst includes hydrochloric acid and / or sulfuric acid.
[0040] In some embodiments, the conditions for the polycondensation reaction include: a temperature of 60-90°C, which can be 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, or 90°C; and a time of 1-3 hours, which can be 1 hour, 1.5 hours, 2 hours, 2.5 hours, or 3 hours. The conditions for the curing reaction include: a temperature of 70-100°C, which can be 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, or 100°C.
[0041] In some embodiments, the oil phase comprises at least one of liquid paraffin, cyclohexane, and toluene;
[0042] The emulsifier includes Span 80;
[0043] The mass ratio of the emulsifier to the oil phase is 1-10:100, which can be 1:100, 2:100, 3:100, 4:100, 5:100, 6:100, 7:100, 8:100, 9:100 or 10:100.
[0044] In a second aspect of this application, phenolic resin microspheres prepared by the preparation method described in the first aspect are provided.
[0045] The phenolic resin microspheres have a high adsorption capacity for aluminum ions and a low adsorption rate for iron ions, enabling selective adsorption of aluminum-iron solutions (including solutions with a high aluminum-iron ratio).
[0046] In a third aspect of this application, the application of phenolic resin microspheres prepared by the preparation method described in the first aspect or the phenolic resin microspheres described in the second aspect in the adsorption of aluminum ions is provided.
[0047] The phenolic resin microspheres have excellent selective adsorption properties, enabling selective adsorption of aluminum ions in a liquid system containing aluminum and iron.
[0048] Recycling spent lithium iron phosphate batteries mainly involves stripping and enriching the positive electrode material (primarily a mixture of LiFePO4, conductive agents, and binders), followed by acid leaching (commonly using inorganic acids such as sulfuric acid (H2SO4), hydrochloric acid (HCl), or phosphoric acid (H3PO4)). The lithium, iron, and phosphorus in the LiFePO4 are efficiently dissolved into the leachate (mainly containing Li...).+ Fe 2+ / Fe 3+ PO4 3- This forms a "lithium iron phosphate electrode acid leaching solution," but this leaching solution inevitably contains various impurity ions, including aluminum ions (Al). 3 ⁺) is one of the most important and harmful impurities.
[0049] The phenolic resin microspheres described in this application can be used for the selective adsorption of aluminum ions in lithium iron phosphate leaching solution systems, thereby removing impurities from the leaching solution and avoiding the introduction of other impurities. At the same time, the low adsorption rate for iron ions can reduce the risk of iron ion loss and reduce the loss of recyclable metals, achieving efficient impurity removal.
[0050] The embodiments of this application will be described in detail below with reference to examples. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of this application. For experimental methods in the following embodiments where specific conditions are not specified, please refer to the guidelines given in this application, or follow experimental manuals or conventional conditions in the art, or follow the conditions recommended by the manufacturer, or refer to experimental methods known in the art.
[0051] The raw materials used in the embodiments of this application are as follows:
[0052] Liquid paraffin: Manufacturer: Aladdin, Model: 8042-47-5.
[0053] Example 1
[0054] The steps for preparing phenolic resin microspheres are as follows:
[0055] Polycondensation reaction: Weigh 4.7g phenol (50mmol) and 11g catechol (100mmol) and add them to the reaction vessel. Then add 0.1g hydrochloric acid aqueous solution (hydrochloric acid mass fraction of 37%, containing 1mmol hydrochloric acid), 6.08g formaldehyde solution (formaldehyde mass fraction of 37%, containing 75mmol formaldehyde) and 1.5g hydroxyacetaldehyde (25mmol). Stir and heat to 60℃ to carry out polycondensation reaction for 2h to prepare prepolymer.
[0056] Curing reaction: Add 50g of liquid paraffin and 5.8g of Span80 to the prepolymer and stir thoroughly to form a uniform solution. Maintain a stirring speed of 2000rpm, heat to 100℃, and keep warm for 6h until the phenolic resin microspheres are completely cured. Then, cool, separate, wash, and dry to prepare phenolic resin microspheres.
[0057] Example 2
[0058] The steps for preparing phenolic resin microspheres are as follows:
[0059] Polycondensation reaction: Weigh 100 mmol of phenol and 100 mmol of sulfosalicylic acid and add them to the reaction vessel. Then add 1 mmol of sulfuric acid aqueous solution (5 mL, 0.2 M), 6.08 g of formaldehyde solution (formaldehyde mass fraction of 37%, containing 75 mmol of formaldehyde) and 2.25 g of glyceraldehyde (25 mmol). Stir and heat to 80 °C to carry out polycondensation reaction for 2 h to prepare prepolymer.
[0060] Curing reaction: Add 100g cyclohexane and 5.8g Span80 to the prepolymer and stir to form a uniform solution. Maintain a stirring speed of 2000rpm, heat to 85℃, and keep warm for 8h until the phenolic resin microspheres are completely cured. Then, cool, separate, wash, and dry to prepare phenolic resin microspheres.
[0061] Example 3
[0062] The steps for preparing phenolic resin microspheres are as follows:
[0063] Polycondensation reaction: Weigh 150 mmol of phenol and 100 mmol of 8-hydroxyquinoline and add them to the reaction vessel. Then add 0.1 g of hydrochloric acid (hydrochloric acid mass fraction of 37%, containing 1 mmol of hydrochloric acid), 6.08 g of formaldehyde solution (formaldehyde mass fraction of 37%, containing 75 mmol of formaldehyde), and 25 mmol of acetaldehyde. Stir and heat to 90 °C to carry out the polycondensation reaction for 2 h to prepare the prepolymer.
[0064] Curing reaction: Add 130g toluene and 5.8g Span80 to the prepolymer, stir to form a uniform solution, maintain a stirring speed of 2000rpm, heat to 75℃, keep warm for 6h until the phenolic resin microspheres are completely cured, and then cool, separate, wash and dry to prepare phenolic resin microspheres.
[0065] Example 4
[0066] The steps for preparing phenolic resin microspheres are as follows:
[0067] Polycondensation reaction: Weigh 50 mmol of phenol and 100 mmol of catechol and add them to the reaction vessel. Then add 0.1 g of hydrochloric acid (hydrochloric acid mass fraction of 37%, containing 1 mmol of hydrochloric acid), 4.06 g of formaldehyde solution (formaldehyde mass fraction of 37%, containing 50 mmol of formaldehyde) and 3 g of hydroxyacetaldehyde (50 mmol). Stir and heat to 60 °C to carry out polycondensation reaction for 2 h to prepare prepolymer.
[0068] Curing reaction: Add 50g of liquid paraffin and 5.8g of Span80 to the prepolymer and stir thoroughly to form a uniform solution. Maintain a stirring speed of 2000rpm, heat to 100℃ and keep at that temperature for 6h until the phenolic resin microspheres are completely cured. Then, cool, separate, wash and dry to prepare phenolic resin microspheres.
[0069] Example 5
[0070] The steps for preparing phenolic resin microspheres are as follows:
[0071] Polycondensation reaction: Weigh 100 mmol of phenol and 100 mmol of sulfosalicylic acid and add them to the reaction vessel. Then add 1 mmol of sulfuric acid solution (5 mL, 0.2 M), 4.05 g of formaldehyde solution (formaldehyde mass fraction of 37%, containing 50 mmol of formaldehyde) and 4.5 g of glyceraldehyde (50 mmol). Stir and heat to 80 °C to carry out polycondensation reaction for 2 h to prepare prepolymer.
[0072] Curing reaction: Add 100g cyclohexane and 5.8g Span80 to the prepolymer and stir to form a uniform solution. Maintain a stirring speed of 2000rpm, heat to 85℃, and keep at this temperature for 8h until the phenolic resin microspheres are completely cured. Then, cool, separate, wash, and dry to prepare phenolic resin microspheres.
[0073] Example 6
[0074] The steps for preparing phenolic resin microspheres are as follows:
[0075] Polycondensation reaction: Weigh 150 mmol of phenol and 100 mmol of 8-hydroxyquinoline and add them to the reaction vessel. Then add 0.1 g of hydrochloric acid (hydrochloric acid mass fraction of 37%, containing 1 mmol of hydrochloric acid), 4.06 g of formaldehyde solution (formaldehyde mass fraction of 37%, containing 50 mmol of formaldehyde) and 2.2 g of acetaldehyde (50 mmol). Stir and heat to 90 °C to carry out polycondensation reaction for 2 h to prepare prepolymer.
[0076] Curing reaction: Add 130g toluene and 5.8g Span80 to the prepolymer, stir to form a uniform solution, maintain a stirring speed of 2000rpm, heat to 75℃, and keep at this temperature for 6h until the phenolic resin microspheres are completely cured; then cool, separate, wash, and dry to prepare phenolic resin microspheres.
[0077] Example 7
[0078] The process for producing condensed phenolic resin microspheres is as follows:
[0079] Polymerization reaction: Weigh 50 mmol of phenol and 100 mmol of catechol and add them to the reaction vessel. Then add 0.1 g of hydrochloric acid solution (hydrochloric acid mass fraction of 37%, containing 1 mmol of hydrochloric acid), 4.06 g of formaldehyde solution (formaldehyde mass fraction of 37%, containing 50 mmol of formaldehyde) and 1.5 g of hydroxyacetaldehyde (25 mmol). Stir and heat to 60 °C to carry out polycondensation reaction for 2 h to prepare prepolymer.
[0080] Curing reaction: Add 50g of liquid paraffin and 5.8g of Span80 to the prepolymer and stir thoroughly to form a uniform solution. Maintain a stirring speed of 2000rpm, heat to 100℃, and keep warm for 6h until the phenolic resin microspheres are completely cured. Then, cool, separate, wash, and dry to prepare phenolic resin microspheres.
[0081] Example 8
[0082] The steps for preparing phenolic resin microspheres are as follows:
[0083] Polycondensation reaction: Weigh 100 mmol of phenol and 100 mmol of sulfosalicylic acid and add them to the reaction vessel. Then add 1 mmol of sulfuric acid solution (5 mL, 0.2 M), 4.05 g of formaldehyde solution (formaldehyde mass fraction of 37%, containing 50 mmol of formaldehyde) and 2.25 g of glyceraldehyde (25 mmol). Stir and heat to 80 °C to carry out polycondensation reaction for 2 h to prepare prepolymer.
[0084] Curing reaction: Add 100g cyclohexane and 5.8g Span80 to the prepolymer and stir to form a uniform solution. Maintain a stirring speed of 2000rpm, heat to 85℃, and keep at this temperature for 8h until the phenolic resin microspheres are completely cured. Then, cool, separate, wash, and dry to prepare phenolic resin microspheres.
[0085] Example 9
[0086] The steps for preparing phenolic resin microspheres are as follows:
[0087] Polycondensation reaction: Weigh 150 mmol of phenol and 100 mmol of 8-hydroxyquinoline and add them to the reaction vessel. Then add 0.1 g of hydrochloric acid (hydrochloric acid mass fraction of 37%, containing 1 mmol of hydrochloric acid), 4.05 g of formaldehyde solution (formaldehyde mass fraction of 37%, containing 50 mmol of formaldehyde), and 1.1 g of acetaldehyde (25 mmol). Stir and heat to 90 °C to carry out the polycondensation reaction for 2 h to prepare the prepolymer.
[0088] Curing reaction: Add 100g toluene and 5.8g Span80 to the prepolymer, stir to form a uniform solution, maintain a stirring speed of 2000rpm, heat to 75℃, and keep at this temperature for 6h until the phenolic resin microspheres are completely cured; then cool, separate, wash, and dry to prepare phenolic resin microspheres.
[0089] Example 10
[0090] The process for producing condensed phenolic resin microspheres is as follows:
[0091] Polymerization reaction: Weigh 50 mmol of phenol and 100 mmol of catechol and add them to the reaction vessel. Then add 0.1 g of hydrochloric acid solution (hydrochloric acid mass fraction of 37%, containing 1 mmol of hydrochloric acid), 6.08 g of formaldehyde solution (formaldehyde mass fraction of 37%, containing 75 mmol of formaldehyde) and 2.25 g of glyceraldehyde (25 mmol). Stir and heat to 80 °C to carry out polycondensation reaction for 2 h to prepare prepolymer.
[0092] Curing reaction: Add 130g toluene and 5.8g Span80 to the prepolymer and stir thoroughly to form a uniform solution. Maintain a stirring speed of 2000rpm, heat to 100℃, and keep warm for 6h until the phenolic resin microspheres are completely cured. Then, cool, separate, wash, and dry to prepare phenolic resin microspheres.
[0093] Example 11
[0094] The process for producing condensed phenolic resin microspheres is as follows:
[0095] Polymerization reaction: Weigh 150 mmol of phenol and 100 mmol of catechol and add them to the reaction vessel. Then add 0.1 g of hydrochloric acid solution (hydrochloric acid mass fraction of 37%, containing 1 mmol of hydrochloric acid), 6.08 g of formaldehyde solution (formaldehyde mass fraction of 37%, containing 75 mmol of formaldehyde) and 2.25 g of glyceraldehyde (25 mmol). Stir and heat to 80 °C to carry out polycondensation reaction for 2 h to prepare prepolymer.
[0096] Curing reaction: Add 130g toluene and 5.8g Span80 to the prepolymer and stir thoroughly to form a uniform solution. Maintain a stirring speed of 2000rpm, heat to 100℃, and keep warm for 6h until the phenolic resin microspheres are completely cured. Then, cool, separate, wash, and dry to prepare phenolic resin microspheres.
[0097] Example 12
[0098] The process for producing condensed phenolic resin microspheres is as follows:
[0099] Polymerization reaction: Weigh 200 mmol of phenol and 100 mmol of catechol and add them to the reaction vessel. Then add 0.1 g of hydrochloric acid solution (hydrochloric acid mass fraction of 37%, containing 1 mmol of hydrochloric acid), 6.08 g of formaldehyde solution (formaldehyde mass fraction of 37%, containing 75 mmol of formaldehyde) and 2.25 g of glyceraldehyde (25 mmol). Stir and heat to 80 °C to carry out polycondensation reaction for 2 h to prepare prepolymer.
[0100] Curing reaction: Add 130g toluene and 5.8g Span80 to the prepolymer and stir thoroughly to form a uniform solution. Maintain a stirring speed of 2000rpm, heat to 100℃, and keep warm for 6h until the phenolic resin microspheres are completely cured. Then, cool, separate, wash, and dry to prepare phenolic resin microspheres.
[0101] Comparative Example 1
[0102] The process for producing condensed phenolic resin microspheres is as follows:
[0103] Polymerization reaction: Weigh 10 mmol of phenol and 100 mmol of catechol and add them to the reaction vessel. Then add 0.1 g of hydrochloric acid solution (hydrochloric acid mass fraction of 37%, containing 1 mmol of hydrochloric acid), 6.08 g of formaldehyde solution (formaldehyde mass fraction of 37%, containing 75 mmol of formaldehyde) and 2.25 g of glyceraldehyde (25 mmol). Stir and heat to 80 °C to carry out polycondensation reaction for 2 h to prepare prepolymer.
[0104] Curing reaction: Add 130g toluene and 5.8g Span80 to the prepolymer and stir thoroughly to form a uniform solution. Maintain a stirring speed of 2000rpm, heat to 100℃, and keep warm for 6h until the phenolic resin microspheres are completely cured. Then, cool, separate, wash, and dry to prepare phenolic resin microspheres.
[0105] Comparative Example 2
[0106] The process for producing condensed phenolic resin microspheres is as follows:
[0107] Polymerization reaction: Weigh 250 mmol of phenol and 100 mmol of catechol and add them to the reaction vessel. Then add 0.1 g of hydrochloric acid solution (hydrochloric acid mass fraction of 37%, containing 1 mmol of hydrochloric acid), 6.08 g of formaldehyde solution (formaldehyde mass fraction of 37%, containing 75 mmol of formaldehyde) and 2.25 g of glyceraldehyde (25 mmol). Stir and heat to 80 °C to carry out polycondensation reaction for 2 h to prepare prepolymer.
[0108] Curing reaction: Add 130g toluene and 5.8g Span80 to the prepolymer and stir thoroughly to form a uniform solution. Maintain a stirring speed of 2000rpm, heat to 100℃, and keep warm for 6h until the phenolic resin microspheres are completely cured. Then, cool, separate, wash, and dry to prepare phenolic resin microspheres.
[0109] Comparative Example 3
[0110] The process for producing condensed phenolic resin microspheres is as follows:
[0111] Polymerization reaction: Weigh 300 mmol of phenol and 100 mmol of catechol and add them to the reaction vessel. Then add 0.1 g of hydrochloric acid solution (hydrochloric acid mass fraction of 37%, containing 1 mmol of hydrochloric acid), 6.08 g of formaldehyde solution (formaldehyde mass fraction of 37%, containing 75 mmol of formaldehyde) and 2.25 g of glyceraldehyde (25 mmol). Stir and heat to 80 °C to carry out polycondensation reaction for 2 h to prepare prepolymer.
[0112] Curing reaction: Add 130g toluene and 5.8g Span80 to the prepolymer and stir thoroughly to form a uniform solution. Maintain a stirring speed of 2000rpm, heat to 100℃, and keep warm for 6h until the phenolic resin microspheres are completely cured. Then, cool, separate, wash, and dry to prepare phenolic resin microspheres.
[0113] Experimental Example 1
[0114] Adsorption performance study
[0115] The phenolic resin microspheres prepared in Examples 1-12 and Comparative Examples 1-3 were subjected to adsorption experiments on simulated solutions. Specifically, 5g of the phenolic resin microspheres prepared in Examples 1-12 and Comparative Examples 1-3 were added to 100mL of lithium iron phosphate acid leaching solution at pH=1.5 (where Fe... 3+ The content is approximately 20,000 mg / L, Al 3+ (Content approximately 200 mg / L), water bath at 25°C, adsorption with shaking for 6 hours, and analysis of Fe in the simulated feed solution before and after adsorption using ICP-AES. 3+ And Al 3+ The Fe was measured and calculated. 3+ And Al 3+ The adsorption rate.
[0116] The results are shown in Table 1. Table 1 shows that the phenolic resin microspheres prepared in Examples 1-12 of this application have a positive effect on Al 3+ The adsorption rate is 88.3%-93.69%, for Fe 3+ The adsorption rate is no more than 7%, indicating that the phenolic resin microspheres prepared in this application can selectively and efficiently adsorb Al from lithium iron phosphate leaching solution.3+ At the same time, for Fe 3+ The adsorption rate is low, not exceeding 7%, achieving efficient and selective adsorption of aluminum ions.
[0117] Comparing Examples 10-12 and Comparative Examples 1-3, it can be seen that, compared with Comparative Examples 1-3 using phenol and other phenolic compounds such as catechol in a molar ratio of 0.1:1, 2.5:1, or 3:1, Examples 10-12 using phenol and other phenolic compounds such as catechol in a molar ratio of 0.5-2:1, the phenolic resin microspheres have a better effect on Fe 3+ The adsorption rate decreased from 22.41%-56.19% to 1.16%-6.63%, for Al 3+ The adsorption rate increased from 57.79%-77.73% to 92.20%-92.93%, significantly improving the adsorption rate of aluminum ions by phenolic resin microspheres, while significantly reducing the adsorption rate of Fe by phenolic resin microspheres. 3+ The adsorption rate.
[0118] Comparing Examples 1 and 4, it can be seen that, compared with Example 1 which used a molar ratio of 3:1 for formaldehyde and hydroxyacetaldehyde, Example 4 used a molar ratio of 1:1 for formaldehyde and hydroxyacetaldehyde, and its phenolic resin microspheres had a better effect on Fe. 3+ The adsorption rate decreased by 60%, for Al 3+ The adsorption rate increased from 91.51% to 92.31%.
[0119] Comparing Examples 2 and 5, it can be seen that, compared with Example 2 which used a molar ratio of 3:1 for formaldehyde and glyceraldehyde, Example 5 used a 1:1 ratio for formaldehyde and glyceraldehyde, and its phenolic resin microspheres had a better effect on Fe. 3+ The adsorption rate decreased by 40%, for Al 3+ The adsorption rate increased from 89.60% to 93.69%.
[0120] Comparing Examples 3 and 6, it can be seen that, compared to Example 3 which used a molar ratio of 3:1 for formaldehyde and acetaldehyde, Example 6 used a 1:1 ratio for formaldehyde and acetaldehyde, and its phenolic resin microspheres had a better effect on Fe... 3+ The adsorption rate decreased by 19%, for Al 3+ The adsorption rate increased from 88.35% to 90.82%.
[0121] Table 1. Adsorption properties of phenolic resin microspheres in Examples 1-12 and Comparative Examples 1-3
[0122]
[0123]
[0124] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0125] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.
Claims
1. A method for producing a phenol-formaldehyde resin microsphere, characterized by comprising the steps of: The method comprises the following steps: mixing phenolic compounds, aldehyde compounds and acid catalysts to prepare a prepolymer through polycondensation reaction; mixing the prepolymer with an oil phase and an emulsifier to prepare phenolic resin microspheres through curing reaction; the phenolic compounds comprise phenol and other phenolic compounds in a molar ratio of 0.5-2:
1.
2. The production method according to claim 1, characterized by, the other phenolic compounds comprise at least one of salicylic acid, amino salicylic acid, sulfosalicylic acid, catechol, pyrogallol and 8-hydroxyquinoline.
3. The production method according to claim 1, characterized by, the aldehyde compounds comprise formaldehyde and other aldehyde compounds; the other aldehyde compounds comprise at least one of acetaldehyde, hydroxyacetaldehyde, propyl aldehyde and glycerol aldehyde.
4. The production method according to claim 3, characterized by, the molar ratio of the formaldehyde and the other aldehyde compounds is 1-3:
1.
5. The method of any one of claims 1-4, wherein, the acid catalysts comprise hydrochloric acid and / or sulfuric acid.
6. The method of any one of claims 1-4, wherein, the molar ratio of the acid catalysts and the phenolic compounds is 0.1-1:100; the molar ratio of the phenolic compounds and the aldehyde compounds is 1-4:
1.
7. The method of any one of claims 1-4, wherein, the polycondensation reaction is carried out at a temperature of 60-90℃ for 1-3h; the curing reaction is carried out at a temperature of 70-100℃.
8. The method of any one of claims 1-4, wherein, the oil phase comprises at least one of liquid paraffin, cyclohexane and toluene; the emulsifier comprises Span 80; the mass ratio of the emulsifier and the oil phase is 1-10:
100.
9. The phenolic resin microspheres prepared by the preparation method of any one of claims 1-8.
10. The phenolic resin microspheres prepared by the preparation method of any one of claims 1-8 or the phenolic resin microspheres of claim 9 for use in adsorbing aluminum ions.