Preparation method and application of a biomass-based super-crosslinked polymer

Abstract

The application relates to a preparation method and application of a biomass-based hypercrosslinked polymer and a porous adsorbent preparation technology field, and is characterized in that after coffee grounds SCGs are defatted, an extract is obtained through ultrasonic-assisted solvent extraction, 4,4-dichloromethyl biphenyl is used as a crosslinking agent, and iron chloride is used as a catalyst to catalyze crosslinking to form a hypercrosslinked polymer. 2 The hypercrosslinked polymer prepared by using the coffee grounds as a biomass raw material and through a specific extraction process has excellent specific surface area, the BET specific surface area reaches 1575 m 2 / g, the polymer structure stability is excellent, the adsorption performance on triazole substances is excellent, the maximum adsorption capacity of triadimefon and tebuconazole is 262.16 mg / g and 264.04 mg / g respectively, the adsorption performance of the material is kept above 90% under different pH, which indicates that the material has good chemical stability, in addition, the polymer also has excellent cycle stability, and the adsorption efficiency on triadimefon and other triazole substances is kept above 90% after repeated adsorption and desorption for 5 times.

Description

Technical Field

[0001] This invention relates to the field of adsorbent preparation technology, specifically to a method for preparing and applying a biomass-based hypercrosslinked polymer. Background Technology

[0002] Triazole pesticides, as an important class of fungicides, are widely used in global agriculture, playing a crucial role in ensuring food security and increasing crop yields. However, with the increasing popularity of the concept of integrated health and safety, the negative impacts of these pesticides on non-target organisms and the ecological environment are becoming increasingly prominent. In particular, the issue of residues in aquatic ecosystems has attracted much attention. Reports have indicated that triazole pesticides in environmental water bodies can accumulate in aquatic organisms and eventually accumulate in humans through drinking water supplies or the food chain. Even low concentrations can pose threats to human health, such as interfering with the endocrine system, inhibiting enzyme activity, causing liver toxicity, and potential carcinogenic risks. Therefore, effectively removing triazole pesticide residues from water is crucial for maintaining ecological security and human health.

[0003] Given the residues and potential risks of triazole pesticides in aquatic environments, adsorption technology plays a crucial role in water pollution control due to its ease of operation and lack of byproduct generation. However, the production of existing adsorbents often relies on high-cost and energy-intensive raw materials, limiting their large-scale application. To address this issue, converting biomass waste into adsorbent materials is considered a low-cost and environmentally friendly approach.

[0004] Coffee, the world's second-largest commercially available beverage, generates a significant amount of solid waste during its processing, primarily coffee grounds. Statistics show that every kilogram of coffee beans produces two kilograms of wet coffee grounds, most of which are discarded directly. The phenols, caffeine, and tannins contained in these grounds may pose a threat to the environment. Recent research has focused on the recycling of coffee grounds, particularly their potential role as a source of polyphenolic compounds such as chlorogenic acid, caffeic acid, p-coumaric acid, gallic acid, and ferulic acid. These compounds are rich in functional groups such as hydroxyl, carboxyl, and ester groups, making them ideal precursors for developing high-performance adsorbent materials.

[0005] Hypercrosslinked polymers, as an emerging porous polymer, are amorphous microporous three-dimensional network materials formed by covalent bonds. They have attracted considerable attention in the adsorption field due to their excellent stability, high specific surface area, and porous structure. The synthesis of hypercrosslinked polymers mainly relies on three process routes: post-crosslinking, one-step self-condensation, and external crosslinking. Among these, external crosslinking, by using crosslinking agents of different chain lengths, not only endows the material with diversity and controllability of pore structure but also broadens the selection range of monomers, facilitating the introduction of various functional groups to obtain adsorbents with different properties. The deeply crosslinked aromatic skeleton gives hypercrosslinked polymers high rigidity and well-developed hierarchical channels, effectively preventing the dense stacking of polymer chains and thus forming stable permanent pores within them. This promotes the diffusion and retention of adsorbates into the material's interior, rather than being limited to surface adsorption, thus showing great application prospects and development potential in the field of water pollution treatment. Summary of the Invention

[0006] The purpose of this invention is to provide a biomass-based hypercrosslinked polymer. This polymer material enables the recycling of waste biomass resources, reduces biomass pollution to the environment, and effectively removes triazole fungicides from water.

[0007] Another objective of this invention is to provide a method for preparing the aforementioned biomass-based hypercrosslinked polymer. This method significantly increases the specific surface area of ​​the polymer, and the prepared hypercrosslinked polymer exhibits excellent thermal stability. Through the chemical interaction between the polar groups on its surface and the target adsorbate, it demonstrates excellent adsorption performance for triazole fungicides, as well as excellent stability and reusability.

[0008] A third objective of this invention is to provide applications of the aforementioned bio-based hypercrosslinked polymer.

[0009] The objective of this invention is achieved through the following technical solution:

[0010] A biomass-based hypercrosslinked polymer is characterized by: using coffee grounds (SCGs) as biomass raw material, obtaining an extract through ultrasonic-assisted solvent extraction, and using 4,4-dichloromethylbiphenyl and ferric chloride as catalysts to catalyze crosslinking to form a hypercrosslinked polymer.

[0011] Furthermore, the ultrasound-assisted solvent extraction involves dispersing defatted SCGs in a mixed solution of ethanol and water, performing ultrasound-assisted extraction, collecting the supernatant by centrifugation, and finally, rotary evaporation to obtain coffee grounds extract.

[0012] Furthermore, the defatted SCGs are dispersed in the mixed solution at a solid-liquid ratio of 1:50, in g / mL, and the volume ratio of ethanol to water in the mixed solution is 1:1.

[0013] Furthermore, the ultrasonic power is 500~600W, the extraction temperature is 55~65℃, and the extraction time is 30~40min.

[0014] Furthermore, the catalytic crosslinking involves dissolving the SCG extract and crosslinking agent 4,4-dichloromethylbiphenyl in dichloroethane, adding anhydrous FeCl3 as a catalyst, heating the reaction system to 40-50°C and stirring for 4-5 h, then raising the temperature to 75-85°C and continuing the reaction for 18-20 h to complete the polymerization. After the reaction system cools to room temperature, the precipitate is collected by centrifugation and washed with methanol until the filtrate is colorless. The product is then vacuum dried at 60°C to obtain the biomass-based hypercrosslinked polymer.

[0015] Furthermore, the ratio of the SCG extract, crosslinking agent, and catalyst is 0.44~0.46: 2.8~3.0: 4.4~4.6.

[0016] A method for preparing a biomass-based hypercrosslinked polymer is characterized by: defatting coffee grounds (SCGs), extracting the extract by ultrasonic-assisted solvent extraction, and using 4,4-dichloromethylbiphenyl and ferric chloride as catalysts to catalyze crosslinking to form a hypercrosslinked polymer.

[0017] Furthermore, the ultrasound-assisted solvent extraction involves dispersing defatted SCGs in a mixed solution of ethanol and water, performing ultrasound-assisted extraction, collecting the supernatant by centrifugation, and finally, rotary evaporation to obtain coffee grounds extract.

[0018] Furthermore, the defatted SCGs are dispersed in the mixed solution at a solid-liquid ratio of 1:50, in g / mL, and the volume ratio of ethanol to water in the mixed solution is 1:1.

[0019] Furthermore, the ultrasonic power is 500~600W, the extraction temperature is 55~65℃, and the extraction time is 30~40min.

[0020] Furthermore, the catalytic crosslinking involves dissolving the SCG extract and crosslinking agent 4,4-dichloromethylbiphenyl in dichloroethane, adding anhydrous FeCl3 as a catalyst, heating the reaction system to 40-50°C and stirring for 4-5 h, then raising the temperature to 75-85°C and continuing the reaction for 18-20 h to complete the polymerization. After the reaction system cools to room temperature, the precipitate is collected by centrifugation and washed with methanol until the filtrate is colorless. The product is then vacuum dried at 60°C to obtain the biomass-based hypercrosslinked polymer.

[0021] Furthermore, the ratio of the SCG extract, crosslinking agent, and catalyst is 0.44~0.46: 2.8~3.0: 4.4~4.6.

[0022] Most specifically, a method for preparing a biomass-based hypercrosslinked polymer is characterized by comprising the following steps:

[0023] Step 1:

[0024] Coffee grounds (SCGs) were repeatedly rinsed with deionized water. The washed SCGs were dried at 70°C and ground into fine powder. The dried SCGs powder was dispersed in a hexane-ethanol mixture and stirred at 300-500 rpm and 30-35°C for 1.5-2 hours. The mixture was then centrifuged, and the lower solid layer was collected and dried to obtain defatted SCGs. The solid-liquid ratio of the SCGs to the mixture was 1:8-10 (in g / mL), and the volume ratio of hexane to ethanol in the mixture was 3:0.8-1.

[0025] Step Two:

[0026] The defatted SCGs prepared in step one were dispersed in a mixed solution of ethanol and water, and after ultrasonic-assisted extraction, centrifuged at 5500~6500 r / min, and the supernatant was collected. Finally, the supernatant was rotary evaporated at 45℃ and vacuum dried to obtain waste coffee grounds extract. The extract was stored in the dark for later use. The solid-liquid ratio of the defatted SCGs dispersed in the mixed solution was 1:50, and the volume ratio of ethanol to water in the mixed solution was 1:1. The ultrasonic power was 500~600W, the extraction temperature was 55~65℃, and the extraction time was 30~40min.

[0027] Step 3:

[0028] The SCGs extract and crosslinking agent 4,4-dichloromethylbiphenyl prepared in step two were dissolved in dichloroethane, and anhydrous FeCl3 catalyst was added. The reaction system was heated to 40-50°C and stirred for 4-5 h, then heated to 75-85°C and reacted for another 18-20 h to complete the polymerization. After the reaction system cooled to room temperature, the precipitate was collected by centrifugation and washed with methanol until the filtrate was colorless. The product was vacuum dried at 60°C to obtain the biomass-based hypercrosslinked polymer. The ratio of SCGs extract, crosslinking agent and catalyst was 0.44-0.46: 2.8-3.0: 4.4-4.6.

[0029] The porous network structure of hypercrosslinked polymers provides abundant diffusion channels and adsorption sites for target substances. Its high specific surface area and large pore volume facilitate rapid molecular penetration into the material's interior, effectively increasing the contact area between the adsorbent per unit mass and the target analyte. Through adsorption mechanisms such as π-π stacking, hydrogen bonding, hydrophobic interactions, electrostatic interactions, and pore-filling effects, the adsorption capacity and rate are further enhanced.

[0030] This hypercrosslinked polymer is a hypercrosslinked monolithic structure formed by randomly crosslinking phenolic substances such as chlorogenic acid and coumaric acid through a crosslinking agent. Different monomers have different effects on triazole substances, thereby synergistically improving the efficient and broad-spectrum adsorption of triazole substances.

[0031] The application of the above-mentioned hypercrosslinked polymers in the adsorption and separation of triazole substances.

[0032] Furthermore, the triazole substance is tebuconazole or triazole.

[0033] The present invention has the following technical effects:

[0034] In this invention, coffee grounds are used as a biomass raw material. The extract obtained through a specific extraction process produces a hypercrosslinked polymer with an excellent specific surface area, reaching a BET specific surface area of ​​1575 m². 2 The polymer exhibits excellent structural stability and superior adsorption performance for triazoles. The maximum adsorption capacities for triazole alcohol and tebuconazole are 262.16 mg / g and 264.04 mg / g, respectively. The adsorption performance remains above 90% at different pH levels, indicating good chemical stability. Furthermore, the polymer demonstrates excellent cyclic stability; after five repeated adsorption-desorption cycles, the adsorption efficiency for triazoles such as triazole alcohol remains above 90%. Attached Figure Description

[0035] Figure 1 Infrared spectrum of the SCGs extract prepared in Example 1.

[0036] Figure 2 Infrared spectra of the biomass-based hypercrosslinked polymer prepared in Example 1 before and after adsorption.

[0037] Figure 3 X-ray photoelectron spectroscopy of the biomass-based hypercrosslinked polymer prepared in Example 1.

[0038] Figure 4 Example 1 shows the adsorption capacity curves of the biomass-based hypercrosslinked polymer for different concentrations of triazole and tebuconazole.

[0039] Figure 5 Example 1: Langmuir fitted adsorption isotherms of the biomass-based hypercrosslinked polymers prepared for the adsorption of triazole and tebuconazole.

[0040] Figure 6 Adsorption kinetics fitting curve of the biomass-based hypercrosslinked polymer prepared in Example 1.

[0041] Figure 7 Example 1: Adsorption-desorption cycle curve of biomass-based hypercrosslinked polymer prepared.

[0042] Figure 8 Example 1 shows the adsorption performance curves of the biomass-based hypercrosslinked polymer at different pH values.

[0043] Figure 9 Example 1, Comparative Example 1 and Comparative Example 2: Comparison of the adsorption efficiency of biomass-based hypercrosslinked polymers for triazole and tebuconazole.

[0044] Figure 10 Thermogravimetric analysis curves of biomass-based hypercrosslinked polymers prepared in Examples 1, 1, and 2. Detailed Implementation

[0045] The present invention will be specifically described below through embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Those skilled in the art can make some non-essential improvements and adjustments to the present invention based on the above description.

[0046] Example 1

[0047] A method for preparing a biomass-based hypercrosslinked polymer includes the following steps:

[0048] Step 1:

[0049] Coffee grounds (SCGs) were repeatedly rinsed with deionized water, dried at 70°C, and ground into a fine powder. The dried SCG powder was dispersed in a hexane-ethanol mixture and stirred at 400 rpm at 35°C for 1.5 h. The mixture was then centrifuged, and the lower solid layer was collected and dried to obtain defatted SCGs. The solid-liquid ratio of the SCGs to the mixture was 1:9 (in g / mL), and the volume ratio of hexane to ethanol in the mixture was 3:0.9.

[0050] Step Two:

[0051] The defatted SCGs prepared in step one were dispersed in a mixed solution of ethanol and water. After ultrasonic-assisted extraction, the mixture was centrifuged at 6000 r / min, and the supernatant was collected. Finally, the supernatant was rotary evaporated at 45℃ until traces of liquid adhered to the bottle wall, after which the rotary evaporation was stopped. The residue was then vacuum dried to obtain the waste coffee grounds extract. The extract was stored in the dark for later use. The solid-liquid ratio of the defatted SCGs dispersed in the mixed solution was 1:50 (in g / mL), the volume ratio of ethanol to water in the mixed solution was 1:1, the ultrasonic power was 550W, the extraction temperature was 60℃, and the extraction time was 35 min.

[0052] Step 3:

[0053] The SCGs extract and crosslinking agent 4,4-dichloromethylbiphenyl prepared in step two were dissolved in dichloroethane, and anhydrous FeCl3 catalyst was added. The reaction system was heated to 45°C and stirred for 5 h, then heated to 80°C and reacted for another 19 h to complete the polymerization. After the reaction system cooled to room temperature, the precipitate was collected by centrifugation and washed with methanol until the filtrate was colorless. The product was dried under vacuum at 60°C to obtain biomass-based hypercrosslinked polymers (SHCPs). The ratio of SCGs extract, crosslinking agent and catalyst was 0.46:2.93:4.52.

[0054] Based on specific surface area testing, the BET specific surface area of ​​the hypercrosslinked polymer prepared in Example 1 was 1575.0590 m². 2 / g.

[0055] The infrared spectrum of the coffee grounds extract in Example 1 is as follows: Figure 1 As shown, the infrared analysis of the prepared hypercrosslinked polymer before and after adsorption of triazole and tebuconazole is as follows. Figure 2 As shown, at 1400-1600 cm -1 The reduced intensity of characteristic peaks attributable to aromatic C=C bonds confirms the role of π-π conjugation in the adsorption process. Furthermore, a decrease in the intensity of characteristic peaks at 3425 cm⁻¹ was observed. -1 and 1710 cm -1 The characteristic peaks at the analyte are significantly weakened, which is attributed to the formation of hydrogen bonds between the polar groups (hydroxyl and carbonyl) on the SHCP surface and the target analyte.

[0056] The X-ray photoelectron spectroscopy (XPS) full spectrum of the prepared hypercrosslinked polymer is shown below. Figure 3 As shown, the polymer is mainly composed of C and O elements, indicating that the oxygen-containing functional groups in the waste coffee grounds extract are retained after cross-linking, further proving the successful synthesis of the material.

[0057] Adsorption capacity test of the above-prepared biomass hypercrosslinked polymer:

[0058] Five mg of biomass-based hypercrosslinked polymer material and 10 mL of aqueous solutions of triazole fungicides (triazole or tebuconazole) with initial concentrations of (10, 20, 50, 150, 300 mg / L) were placed in an Erlenmeyer flask and mixed thoroughly. The flask was then sealed and placed in a constant-temperature shaker at 200 rpm. After adsorption, a portion of the solution was extracted with a syringe, filtered through a 0.45 μm filter membrane, and the concentration of the remaining analyte in the solution was determined using high-performance liquid chromatography (HPLC). The adsorption isotherms were fitted using the Langmuir, Freundlich, and Henry equations. The adsorption curves for triazole and tebuconazole at concentrations of (10, 20, 50, 100, 300 mg / L) are shown below. Figure 4 As shown, the maximum adsorption capacities of triazole and tebuconazole are 262.16 mg / g and 264.04 mg / g, respectively. The calculation results show that the fitting results using the Langmuir model are as follows... Figure 5 As shown, the R² values ​​for triazole and tebuconazole are 0.998 and 0.993, respectively, which are much higher than those of other models, indicating that the adsorption process of triazole fungicides by SHCPs conforms to the characteristics of monolayer adsorption.

[0059] An adsorption experiment was conducted on 5 mg of biomass-based hypercrosslinked polymer material and 10 mL of a 300 mg / L aqueous solution of triazole fungicide (triazole alcohol). The concentration of the remaining analyte in the solution was measured at different predetermined time points (1, 5, 10, 20, and 60 min). The experimental results were then used to investigate the adsorption kinetics using pseudo-first-order and pseudo-second-order kinetic models.

[0060] The results are as follows Figure 6 As shown, (a) is the adsorption kinetic curve of the biomass-based hypercrosslinked polymer, and (b) is the pseudo-second-order kinetic model, with the calculated pseudo-second-order model R0. 2 The value of 0.999 indicates a significantly higher goodness of fit than the pseudo-first-order model, and its R-value is [value missing]. 2 A higher value indicates that it more accurately reflects the adsorption process. The characteristics of this model suggest that the adsorption process is mainly chemisorption, with physisorption playing a secondary role.

[0061] Adsorption-desorption cycle stability test:

[0062] 5 mg of biomass-based hypercrosslinked polymer material and 10 mL of a 250 mg / L aqueous solution of triazole fungicide (triazole alcohol) were placed in an Erlenmeyer flask and mixed thoroughly. The flask was then sealed and placed in a constant-temperature shaker at 200 rpm. After adsorption, a portion of the solution was drawn off with a syringe, filtered through a 0.45 μm filter membrane, and the concentration of the remaining analyte in the solution was determined using high-performance liquid chromatography (HPLC). After centrifugation, the adsorbed material was collected, washed 2-3 times with anhydrous methanol, and then dried. The above steps were repeated 5 times.

[0063] Adsorption-desorption cycle curves are shown below Figure 7 As shown in the figure, after five adsorption-desorption cycles, the adsorption efficiency of the biomass-based hypercrosslinked polymer for triazole alcohol remains above 90%, indicating that the prepared biomass-based hypercrosslinked polymer has excellent stability and reusability.

[0064] Test on the effect of pH on adsorption performance:

[0065] The pH of the triazole solution was adjusted to the range of 4-11 using 0.1 mL of HCl or NaOH solution. 5 mg of biomass-based hypercrosslinked polymer material and 10 mL of an aqueous solution of triazole fungicide (triazole) were placed in an Erlenmeyer flask and mixed thoroughly. The flask was then sealed and placed in a constant-temperature shaker at 200 rpm. After adsorption, a portion of the solution was drawn off with a syringe, filtered through a 0.45 μm filter membrane, and the concentration of the remaining analyte was determined using high-performance liquid chromatography (HPLC). Adsorption results within the pH range of 3-12 are shown below. Figure 8 As shown, the adsorption efficiency of the material varies slightly within the pH range of 4-11, with a slight increasing trend observed when the pH increases from 4 to 7. Under acidic conditions, the oxygen-containing groups on the adsorbent surface become positively charged due to protonation, leading to electrostatic repulsion with the similarly positively charged triazole, thus reducing adsorption capacity. At pH values ​​below 10.59, the positive charge on the triazole surface electrostatically attracts the negatively charged adsorbent surface. When the pH value approaches 10.59, the triazole becomes neutral, eliminating this electrostatic attraction and further reducing adsorption efficiency. This result indicates that electrostatic interactions exist on the surface during adsorption, and the material's adsorption performance remains above 90% at different pH levels, demonstrating good chemical stability.

[0066] Comparative Example 1

[0067] The difference from Example 1 is that the crosslinking agent is replaced with benzyl dichloroisocyanurate, while the rest of the formulation steps are the same as in Example 1.

[0068] Based on specific surface area testing, the BET specific surface area of ​​the hypercrosslinked polymer prepared in Comparative Example 1 was 1015.8075 m². 2 / g.

[0069] Comparative Example 2

[0070] The difference from Example 1 is that the crosslinking agent is replaced with dimethoxymethane, while the rest of the formulation steps are the same as in Example 1.

[0071] Based on specific surface area testing, the BET specific surface area of ​​the hypercrosslinked polymer prepared in Comparative Example 2 was 48.9163 m². 2 / g.

[0072] The adsorption capacity of 5 mg and 10 mL of a 50 mg / L triazole fungicide (triazole / tebuconazole) prepared in Examples 1, 1, and 2 were tested. The adsorption results are as follows: Figure 9 As shown in the figure, the biomass-based hypercrosslinked polymer prepared in Example 1 achieved an adsorption efficiency of over 97% for both triazole and tebuconazole. In contrast, the adsorption efficiency of the biomass-based hypercrosslinked polymer prepared in Comparative Example 1 for both triazole and tebuconazole decreased significantly to below 90%, and the adsorption efficiency of the hypercrosslinked polymer prepared in Comparative Example 2 for tebuconazole further decreased to below 80%.

[0073] Thermal stability test:

[0074] The thermal stability of the biomass-based hypercrosslinked polymers prepared in Example 1, Comparative Example 1, and Comparative Example 2 was determined by thermogravimetric analysis. Figure 10 As shown. (a) For Example 1, the heat loss below 200°C comes from the evaporation of adsorbed water, while the heat loss above 200°C mainly comes from the decomposition of the polymer network. At 400°C, the biomass-based hypercrosslinked polymer can still retain more than 90% of its mass, showing excellent thermal stability. (b) For the thermal stability of the hypercrosslinked polymer prepared in Comparative Example 1, it can be seen that the heat loss below 200°C comes from the evaporation of adsorbed water, while the heat loss above 200°C mainly comes from the decomposition of the polymer network. At 400°C, the material can still retain more than 90% of its mass, showing excellent thermal stability, but overall slightly lower than that of Example 1. (c) For the thermal stability of the hypercrosslinked polymer prepared in Comparative Example 2, it can be found that the material begins to decompose at 200°C, and the thermal stability is significantly lower than that of Example 1. This may be because the degree of crosslinking is low when dimethoxymethane is used as a crosslinking agent in this experiment, resulting in poor polymer stability and easy decomposition of the polymer structure.

[0075] Comparative Example 3

[0076] The difference between Example 1 and Example 2 lies in the preparation process of the SCGs extract (step two). The remaining steps are the same as in Example 1, and the specific steps are as follows:

[0077] Solvent extraction: Compared with Example 1 (ultrasound-assisted solvent), no ultrasound assistance was used, but all other parameters were the same.

[0078] Ultrasonic extraction: Compared with Example 1 (ultrasonic-assisted solvent), the dispersion solvent was water, and all other parameters were the same.

[0079] Enzymatic extraction: Defatted SCGs were dispersed in water, pectinase and cellulase were added, the pH was adjusted to 5, and enzymatic hydrolysis was carried out at 55°C for 2 hours. After enzymatic hydrolysis, the extract was collected according to the remaining operations in step two of Example 1.

[0080] Ultrasound-assisted enzyme extraction: During the extraction process, the same ultrasonic treatment as in Example 1 was added for 35 min.

[0081] The content of several major phenolic acid components in the extracts obtained by different extraction methods varies. The performance of the hypercrosslinked polymer prepared by the same step three operation in Example 1 also varies. The changes of each major component, the specific surface area of ​​the hypercrosslinked polymer and the maximum adsorption capacity for tebuconazole are shown in Table 1.

[0082] Table 1:

[0083]

[0084] It can be seen that the content of the main components extracted by different extraction methods is significantly different, which will have a significant impact on the structure and properties of the polymer obtained after the final hypercrosslinking polymerization, resulting in significant differences in the adsorption of triazole substances.

[0085] Example 2

[0086] A method for preparing a biomass-based hypercrosslinked polymer includes the following steps:

[0087] Step 1:

[0088] Coffee grounds (SCGs) were repeatedly rinsed with deionized water, dried at 70°C, and ground into a fine powder. The dried SCG powder was dispersed in a hexane-ethanol mixture and stirred at 300 rpm and 30°C for 2 hours. The mixture was then centrifuged, and the lower solid layer was collected and dried to obtain defatted SCGs. The solid-liquid ratio of the SCGs to the mixture was 1:10 (in g / mL), and the volume ratio of hexane to ethanol in the mixture was 3:0.8.

[0089] Step Two:

[0090] The defatted SCGs prepared in step one were dispersed in a mixed solution of ethanol and water. After ultrasonic-assisted extraction, the mixture was centrifuged at 5500 r / min, and the supernatant was collected. Finally, the supernatant was rotary evaporated at 45℃ until traces of liquid adhered to the bottle wall, after which the rotary evaporation was stopped. The residue was then vacuum dried to obtain the waste coffee grounds extract. The extract was stored in the dark for later use. The solid-liquid ratio of the defatted SCGs dispersed in the mixed solution was 1:50 (in g / mL), the volume ratio of ethanol to water in the mixed solution was 1:1, the ultrasonic power was 500W, the extraction temperature was 65℃, and the extraction time was 30 min.

[0091] Step 3:

[0092] The SCGs extract and crosslinking agent 4,4-dichloromethylbiphenyl prepared in step two were dissolved in dichloroethane, and anhydrous FeCl3 catalyst was added. The reaction system was heated to 45°C and stirred for 5 h, then heated to 80°C and reacted for another 19 h to complete the polymerization. After the reaction system cooled to room temperature, the precipitate was collected by centrifugation and washed with methanol until the filtrate was colorless. The product was dried under vacuum at 60°C to obtain biomass-based hypercrosslinked polymers (SHCPs). The ratio of SCGs extract, crosslinking agent and catalyst was 0.44:3.0:4.6.

[0093] Example 3

[0094] A method for preparing a biomass-based hypercrosslinked polymer includes the following steps:

[0095] Step 1:

[0096] Coffee grounds (SCGs) were repeatedly rinsed with deionized water, dried at 70°C, and ground into fine powder. The dried SCG powder was dispersed in a hexane-ethanol mixture and stirred at 500 rpm at 30-35°C for 1.5-2 hours. The mixture was then centrifuged, and the lower solid layer was collected and dried to obtain defatted SCGs. The solid-liquid ratio of the SCGs to the mixture was 1:8 (in g / mL), and the volume ratio of hexane to ethanol in the mixture was 3:1.

[0097] Step Two:

[0098] The defatted SCGs prepared in step one were dispersed in a mixed solution of ethanol and water. After ultrasonic-assisted extraction, the mixture was centrifuged at 6500 r / min, and the supernatant was collected. Finally, the supernatant was rotary evaporated at 45℃ until traces of liquid adhered to the bottle wall, after which the rotary evaporation was stopped. The residue was then vacuum dried to obtain the waste coffee grounds extract. The extract was stored in the dark for later use. The solid-liquid ratio of the defatted SCGs dispersed in the mixed solution was 1:50 (in g / mL), the volume ratio of ethanol to water in the mixed solution was 1:1, the ultrasonic power was 600W, the extraction temperature was 55℃, and the extraction time was 40 min.

[0099] Step 3:

[0100] The SCGs extract and crosslinking agent 4,4-dichloromethylbiphenyl prepared in step two were dissolved in dichloroethane, and anhydrous FeCl3 catalyst was added. The reaction system was heated to 45°C and stirred for 5 h, then heated to 80°C and reacted for another 19 h to complete the polymerization. After the reaction system cooled to room temperature, the precipitate was collected by centrifugation and washed with methanol until the filtrate was colorless. The product was dried under vacuum at 60°C to obtain biomass-based hypercrosslinked polymers (SHCPs). The ratio of SCGs extract, crosslinking agent and catalyst was 0.46:2.8:4.4.

Claims

1. A process for the preparation of biomass based hypercrosslinked polymer, characterized by: The extract is obtained by defatting coffee grounds (SCGs) and then using ultrasonic-assisted solvent extraction. 4,4-Dichloromethylbiphenyl is used as a crosslinking agent and ferric chloride is used as a catalyst to catalyze crosslinking to form a hypercrosslinked polymer. The ultrasonic-assisted solvent extraction involves dispersing the defatted SCGs in a mixed solution of ethanol and water, performing ultrasonic-assisted extraction, collecting the supernatant by centrifugation, and finally, rotary evaporation to obtain the coffee grounds extract.

2. The method for preparing a biomass-based hypercrosslinked polymer as described in claim 1, characterized in that: The defatted SCGs were dispersed in the mixed solution at a solid-liquid ratio of 1:50, with units of g / mL, and the volume ratio of ethanol to water in the mixed solution was 1:

1.

3. The method for preparing a biomass-based hypercrosslinked polymer as described in claim 2, characterized in that: The ultrasonic power is 500~600W, the extraction temperature is 55~65℃, and the extraction time is 30~40min.

4. The method for preparing a biomass-based hypercrosslinked polymer as described in claim 3, characterized in that: The catalytic crosslinking process involves dissolving SCG extracts and crosslinking agent 4,4-dichloromethylbiphenyl in dichloroethane, adding anhydrous FeCl3 as a catalyst, heating the reaction system to 40-50°C and stirring for 4-5 h, then raising the temperature to 75-85°C and continuing the reaction for 18-20 h to complete the polymerization. After the reaction system cools to room temperature, the precipitate is collected by centrifugation and washed with methanol until the filtrate is colorless. The product is then vacuum dried at 60°C to obtain the biomass-based hypercrosslinked polymer.

5. The method for preparing a biomass-based hypercrosslinked polymer as described in claim 4, characterized in that: The ratio of the SCG extract, crosslinking agent, and catalyst is 0.44~0.46: 2.8~3.0: 4.4~4.

6.

6. A method for preparing a biomass-based hypercrosslinked polymer, characterized in that, Includes the following steps: Step 1: Coffee grounds (SCGs) were repeatedly rinsed with deionized water. The washed SCGs were dried at 70°C and ground into fine powder. The dried SCG powder was dispersed in a hexane-ethanol mixture and stirred at 300-500 rpm and 30-35°C for 1.5-2 hours. The mixture was then centrifuged, and the lower solid layer was collected and dried to obtain defatted SCGs. The solid-liquid ratio of the SCGs to the mixture was 1:8-10 (in g / mL), and the volume ratio of hexane to ethanol in the mixture was 3:0.8-1. Step Two: The defatted SCGs prepared in step one were dispersed in a mixed solution of ethanol and water, and after ultrasonic-assisted extraction, centrifuged at 5500~6500 r / min, and the supernatant was collected. Finally, the supernatant was rotary evaporated at 45℃ and vacuum dried to obtain waste coffee grounds extract. The extract was stored in the dark for later use. The solid-liquid ratio of the defatted SCGs dispersed in the mixed solution was 1:50, and the volume ratio of ethanol to water in the mixed solution was 1:

1. The ultrasonic power was 500~600W, the extraction temperature was 55~65℃, and the extraction time was 30~40min. Step 3: The SCGs extract and crosslinking agent 4,4-dichloromethylbiphenyl prepared in step two were dissolved in dichloroethane, and anhydrous FeCl3 catalyst was added. The reaction system was heated to 40-50℃ and stirred for 4-5 h, then heated to 75-85℃ and reacted for another 18-20 h to complete the polymerization. After the reaction system cooled to room temperature, the precipitate was collected by centrifugation and washed with methanol until the filtrate was colorless. The product was vacuum dried at 60℃ to obtain the biomass-based hypercrosslinked polymer. The ratio of SCGs extract, crosslinking agent and catalyst was 0.44-0.46: 2.8-3.0: 4.4-4.

6.

7. The application of the hypercrosslinked polymer prepared by the method described in claim 6 in the adsorption and separation of triazole substances.

8. The application as described in claim 7, characterized in that: The triazole substance is tebuconazole or triazole.

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