A selective adsorbent material, its preparation and use
The selective adsorption material prepared solves the problem of HMF separation in fructose production, achieving efficient and low-cost separation of HMF and fructose, and is suitable for fructose purification.
Patent Information
- Application Number
- CN202610384005.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-03-26
- Publication Date
- 2026-06-16
AI Technical Summary
Existing adsorption materials are difficult to efficiently separate fructose and 5-hydroxymethylfurfural (HMF), leading to equipment scaling, low production efficiency, and deterioration of fructose quality in fructose industrial production. Existing technologies such as distillation have high energy consumption, membrane separation has high cost, and chemical reduction is prone to introducing impurities.
Selective adsorbent material was prepared by reflux reaction using sodium 2,5-thiophene dicarboxylate, aluminum chloride, and sodium aluminate as raw materials. The material has a large specific surface area and suitable pore size, and strongly adsorbs HMF by utilizing intermolecular forces and π-π interactions, while having a weak effect on fructose.
It achieves highly selective and rapid sieving separation of HMF and fructose, with low-cost adsorption materials suitable for large-scale industrial production. It has high HMF adsorption capacity and low fructose adsorption capacity, and the separation effect is significant.
Smart Images
Figure CN122209351A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the fields of MOF materials and fructose purification technology, specifically to a selective adsorption material, its preparation method, and its application. Background Technology
[0002] Fructose is a natural functional monosaccharide widely used in food, medicine, and other fields. Industrial fructose production primarily utilizes hydrolysis and isomerization of biomass such as corn cobs. However, during hydrolysis and isomerization, the monosaccharide is susceptible to reaction under acid and high temperatures, producing toxic 5-hydroxymethylfurfural (HMF). The presence of HMF not only degrades fructose quality, exacerbates equipment scaling, and reduces production efficiency, but also interferes with fructose crystallization and purification. Therefore, efficient HMF removal is crucial for the industrial production of high-quality fructose.
[0003] Currently, the main methods for removing HMF from fructose include distillation, membrane separation, chemical reduction, and adsorption. Distillation is energy-intensive and has low separation efficiency; membrane separation is prone to membrane fouling, costly, and difficult to scale up; chemical reduction easily introduces impurities and is cumbersome; while adsorption is simple to operate, energy-efficient, and produces no secondary pollution, making it the most promising method. The core of adsorption is the development of high-performance adsorption materials, but most existing adsorption materials are poorly adapted to the fructose system, have low compatibility with industrial needs, and fail to meet practical application requirements.
[0004] Therefore, it is of great significance to develop an adsorbent material that can achieve highly selective and rapid sieving separation of target components in a mixed solution of HMF and fructose. Summary of the Invention
[0005] The purpose of this invention is to provide a selective adsorption material, its preparation method, and its application.
[0006] The technical solution adopted in this invention is: A method for preparing a selective adsorption material includes the following steps: Sodium 2,5-thiophene dicarboxylate (Na2TDC), aluminum chloride (AlCl3), and sodium aluminate (NaAlO2) were dissolved in water and subjected to reflux reaction. The products were then separated, purified, and dried to obtain a selective adsorption material.
[0007] Preferably, the molar ratio of sodium 2,5-thiophene dicarboxylate, aluminum chloride, and sodium aluminate is 1:0.6-0.9:0.2-0.3.
[0008] Preferably, the sodium 2,5-thiophene dicarboxylate is prepared by a method comprising the following steps: dissolving 2,5-thiophene dicarboxylate (H2TDC) and sodium hydroxide (NaOH) in water and reacting them to obtain sodium 2,5-thiophene dicarboxylate.
[0009] Preferably, the molar ratio of 2,5-thiophene dicarboxylic acid to sodium hydroxide is 1:0.5 to 2.2.
[0010] More preferably, the molar ratio of 2,5-thiophene dicarboxylic acid to sodium hydroxide is 1:2.0 to 2.2.
[0011] Preferably, the ratio of 2,5-thiophene dicarboxylic acid to water is 1 mol: 3000 mL to 6000 mL.
[0012] Preferably, the reflux reaction time is 6h to 10h.
[0013] Preferably, the product separation, purification and drying includes the following steps: centrifuging the reaction solution, washing the solid with water, and then drying.
[0014] Preferably, the drying is carried out at a temperature of 50℃ to 70℃ for a drying time of 20h to 30h.
[0015] A selective adsorbent material prepared by the above-described method.
[0016] Preferably, the selective adsorbent material is spherical with a particle size of 80 nm to 600 nm.
[0017] Preferably, the BET specific surface area of the selective adsorption material is 400 m². 2 / g~650m 2 / g, pore volume 0.35cm 3 / g~0.50cm 3 / g, with a pore size of 6Å to 15Å.
[0018] An application of a selective adsorbent material as described above for adsorbing 5-hydroxymethylfurfural in sugar solutions.
[0019] A method for removing 5-hydroxymethylfurfural from sugar solutions includes the following steps: The above-mentioned selective adsorption material was added to the sugar solution to adsorb 5-hydroxymethylfurfural, and then the solids were removed by filtration to obtain a purified sugar solution.
[0020] Preferably, the concentration of p-5-hydroxymethylfurfural in the sugar solution is 1 g / L to 20 g / L.
[0021] Preferably, the adsorption is carried out at a temperature of 25°C to 65°C.
[0022] Preferably, the adsorption time is 15 min to 60 min.
[0023] The working principle of the selective adsorption material of the present invention: The selective adsorption material of the present invention can strongly adsorb HMF through intermolecular forces and π-π interactions. Due to its large specific surface area and large pore volume, it has a high HMF adsorption capacity. At the same time, since its pore size is slightly smaller than that of fructose, its force on fructose is weaker, thereby achieving the effect of sieving and separating fructose and HMF.
[0024] The beneficial effects of this invention are: the selective adsorption material of this invention has the characteristics of large specific surface area, large pore volume, low surface polarity, and low cost. It can achieve highly selective and rapid sieving and separation of target components in HMF and fructose mixed solutions, and has a very broad application prospect in the field of fructose purification.
[0025] Specifically: 1) The selective adsorption material of this invention has a large specific surface area (BET specific surface area is 400 m²). 2 / g~650m 2 / g), large pore volume (pore volume is 0.35cm) 3 / g~0.50cm 3 ( / g), which can selectively separate HMF and fructose; 2) The selective adsorption material of the present invention has a significant separation effect on the HMF and fructose mixture system. In the mixed solution, its maximum adsorption capacity for HMF can reach 532.5 mg / g, while it has almost no adsorption effect on fructose, thus achieving efficient separation of HMF and fructose. 3) The selective adsorption material of the present invention has a simple preparation method, a wide range of raw material sources, and low production cost, making it suitable for large-scale industrial production and application. Attached Figure Description
[0026] Figure 1 This is a SEM image of the selective adsorption material of Example 1.
[0027] Figure 2 The image shows the XRD pattern of the selective adsorption material in Example 1.
[0028] Figure 3 The nitrogen adsorption-desorption isotherm curve of the selective adsorption material of Example 1 at 77 K.
[0029] Figure 4 This is a pore size distribution diagram of the selective adsorption material in Example 1.
[0030] Figure 5 The HMF-fructose bicomponent competitive adsorption curve is shown for the selective adsorption material of Example 1.
[0031] Figure 6The adsorption time-kinetic curve of the HMF-fructose bicomponent selective adsorption material in Example 1 is shown.
[0032] Figure 7 The HMF-fructose bicomponent adsorption isotherm of the selective adsorption material in Example 1 is shown.
[0033] Figure 8 The breakthrough curve of the HMF-fructose bicomponent fixed bed for the selective adsorption material of Example 1 is shown. Detailed Implementation
[0034] The present invention will be further explained and described below with reference to specific embodiments.
[0035] Example 1: A selective adsorbent material, the preparation method of which is as follows: 1) Add 4.31 g (0.0237 mol) of 2,5-thiophene dicarboxylic acid (H2TDC) and 2.00 g (0.05 mol) of sodium hydroxide (NaOH) to 100 mL of deionized water and stir until completely dissolved to obtain a clear aqueous solution of sodium 2,5-thiophene dicarboxylic acid. 2) Add 18.75 mL of 1 mol / L aluminum chloride (AlCl3) aqueous solution and 12.5 mL of 0.5 mol / L sodium aluminate (NaAlO2) aqueous solution to sodium 2,5-thiophene dicarboxylate aqueous solution, stir and reflux for 6 h, cool to room temperature, centrifuge, take the solid (white) and wash it several times with deionized water, and then dry it in an oven at 60 °C for 24 h to obtain the selective adsorbent material (denoted as CAU-23(Al)).
[0036] Performance testing: 1) The scanning electron microscope (SEM) image of the selective adsorption material (CAU-23(Al)) in this embodiment is shown below. Figure 1 As shown.
[0037] Depend on Figure 1 It can be seen that CAU-23(Al) is in the form of regular spheres with a particle size of about 500 nm.
[0038] 2) The X-ray diffraction (XRD) pattern of the selective adsorption material (CAU-23(Al)) in this embodiment is shown below. Figure 2 As shown.
[0039] Depend on Figure 2 It can be seen that CAU-23(Al) exhibits characteristic diffraction peaks at 2θ of 8.5°, 12.1° and 16.3°, indicating that CAU-23(Al) porous material with good crystallinity was successfully prepared.
[0040] 3) The nitrogen adsorption-desorption isotherm curve of the selective adsorbent material (CAU-23(Al)) in this embodiment at 77 K is shown below. Figure 3 As shown, the aperture distribution diagram is as follows: Figure 4 As shown.
[0041] Depend on Figure 3 and Figure 4 It can be seen that the BET specific surface area of CAU-23(Al) is 400 m². 2 / g~650m 2 / g, pore volume 0.35cm 3 / g~0.50cm 3 / g, with a pore size of 6Å to 15Å.
[0042] 4) Static batch adsorption experiment of HMF-fructose two-component system: Take five 5 mL transparent sample vials, add 30 mg of the selective adsorbent material (CAU-23(Al)) of this embodiment to each vial, and then add 3 mL of HMF-fructose mixed aqueous solution with concentrations of 1 g / L (HMF and fructose are both 1 g / L), 2 g / L, 5 g / L, 10 g / L, and 20 g / L respectively. Place the vials at 25 °C and stir for 120 min (to reach adsorption equilibrium) at a stirring rate of 300 r / min. Centrifuge the vials, and filter the liquid using a syringe fitted with a 0.22 μm aqueous filter. Quantitatively analyze the filtered clear liquid using high-performance liquid chromatography (HPLC). The resulting HMF-fructose two-component competitive adsorption curves are shown below. Figure 5 As shown.
[0043] Depend on Figure 5 It can be seen that when CAU-23(Al) treats a 1 g / L HMF-fructose mixed aqueous solution, the maximum selectivity factor for HMF reaches 60. When CAU-23(Al) treats a 20 g / L HMF-fructose mixed aqueous solution, the maximum adsorption capacity of HMF reaches 521.7 mg / g, and the adsorption capacity of fructose is 15.1 mg / g. The selectivity factor for HMF is greater than 35, indicating that the selective adsorption material of the present invention has a high HMF adsorption capacity and can selectively separate HMF and fructose.
[0044] 5) HMF-fructose two-component adsorption time kinetics experiment: 5 mg of the selective adsorbent material (CAU-23(Al)) of this embodiment was added to a 5 mL transparent sample vial, followed by 3 mL of a 20 g / L HMF-fructose mixed aqueous solution. The vial was then stirred at 25 °C at a stirring rate of 300 r / min. After stirring for 2 min, 4 min, 6 min, 8 min, 10 min, 15 min, 20 min, 30 min, and 60 min, the adsorbate was collected and centrifuged. The liquid was filtered through a syringe fitted with a 0.22 μm aqueous filter. The filtered supernatant was quantitatively analyzed by high performance liquid chromatography. The resulting HMF-fructose two-component adsorption time-kinetic curve is shown below. Figure 6 As shown.
[0045] Depend on Figure 6 It can be seen that HMF is rapidly adsorbed by CAU-23(Al) in the first 5 minutes and reaches adsorption equilibrium in about 15 minutes. The adsorption amount of HMF is 483.0 mg / g and the adsorption amount of fructose is 64.4 mg / g. Subsequently, the adsorption amounts of HMF and fructose remain almost unchanged with the extension of time, indicating that the selective adsorption material of the present invention can selectively separate HMF and fructose.
[0046] 6) HMF-fructose two-component adsorption isotherm experiment: Take three 5 mL transparent sample vials, add 30 mg of the selective adsorbent material (CAU-23(Al)) of this embodiment and 3 mL of a 20 g / L HMF-fructose mixed aqueous solution to each, and then place them at 25 °C, 45 °C, and 65 °C respectively for 120 min (to reach adsorption equilibrium) at a stirring rate of 300 r / min. Centrifuge, collect the liquid and filter it through a syringe equipped with a 0.22 μm aqueous filter. Quantitatively analyze the filtered clear liquid using high performance liquid chromatography. The obtained HMF-fructose two-component adsorption isotherm is shown below. Figure 7 As shown.
[0047] Depend on Figure 7 It can be seen that within the temperature range of 25℃ to 65℃, the adsorption capacity of CAU-23(Al) for the target analyte increases with increasing equilibrium concentration; at the same equilibrium concentration, the adsorption capacity decreases with increasing temperature, which is consistent with the characteristics of the Langmuir monolayer adsorption model.
[0048] 7) HMF-fructose two-component fixed-bed breakthrough experiment: 600 mg of the selective adsorbent material (CAU-23(Al)) of this embodiment was packed into a fixed bed column with a diameter of 1.2 cm and a length of 20 cm (bed height 0.5 cm, density 0.379 g / cm³). 3The sample was fixed in a bed of quartz wool with a thickness of 1.2 cm and 0.6 cm, respectively. A 1 g / L HMF-fructose mixed aqueous solution was then passed through the bed at a flow rate of 0.5 mL / min. The eluent was collected every 2-6 minutes for a total of 160 minutes. After centrifugation, the liquid sample was analyzed quantitatively by high-performance liquid chromatography (HPLC). The breakthrough curve of the HMF-fructose two-component fixed bed is shown below. Figure 8 As shown.
[0049] Depend on Figure 8 It can be seen that HMF begins to penetrate at 48 minutes, and the fructose purity at the penetration point is 92.64%.
[0050] Example 2: A selective adsorbent material, the preparation method of which is as follows: 1) Add 3.23 g (0.0178 mol) of 2,5-thiophene dicarboxylic acid (H2TDC) and 1.50 g (0.0375 mol) of sodium hydroxide (NaOH) to 100 mL of deionized water and stir until completely dissolved to obtain a clear aqueous solution of sodium 2,5-thiophene dicarboxylic acid. 2) Add 14.06 mL of 1 mol / L aluminum chloride (AlCl3) aqueous solution and 9.38 mL of 0.5 mol / L sodium aluminate (NaAlO2) aqueous solution to sodium 2,5-thiophene dicarboxylate aqueous solution, stir and reflux for 6 h, cool to room temperature, centrifuge, take the solid (white) and wash it several times with deionized water, and then dry it in an oven at 60 °C for 24 h to obtain the selective adsorbent material (denoted as CAU-23(Al)).
[0051] According to the test (test method is the same as in Example 1), the maximum adsorption capacity of the selective adsorbent material in this example for HMF is 508.2 mg / g, the adsorption capacity for fructose is 18.5 mg / g, and the HMF selectivity factor is greater than 38. In the range of 25℃ to 65℃, the adsorption capacity of the selective adsorbent material for HMF decreases with increasing temperature, which is consistent with the characteristics of the Langmuir monolayer adsorption model.
[0052] Example 3: A selective adsorbent material, the preparation method of which is as follows: 1) Add 5.39 g (0.0296 mol) of 2,5-thiophene dicarboxylic acid (H2TDC) and 2.50 g (0.0625 mol) of sodium hydroxide (NaOH) to 100 mL of deionized water and stir until completely dissolved to obtain a clear aqueous solution of sodium 2,5-thiophene dicarboxylic acid. 2) Add 23.44 mL of 1 mol / L aluminum chloride (AlCl3) aqueous solution and 15.63 mL of 0.5 mol / L sodium aluminate (NaAlO2) aqueous solution to sodium 2,5-thiophene dicarboxylate aqueous solution, stir and reflux for 6 h, cool to room temperature, centrifuge, take the solid (white) and wash it several times with deionized water, and then dry it in an oven at 60 °C for 24 h to obtain the selective adsorbent material (denoted as CAU-23(Al)).
[0053] According to the test (test method is the same as in Example 1), the maximum adsorption capacity of the selective adsorbent material in this example for HMF is 532.5 mg / g, the adsorption capacity for fructose is 14.2 mg / g, and the HMF selectivity factor is greater than 42. In the range of 25℃ to 65℃, the adsorption capacity of the selective adsorbent material for HMF decreases with increasing temperature, which is consistent with the characteristics of the Langmuir monolayer adsorption model.
[0054] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.
Claims
1. A method for preparing a selective adsorption material, characterized in that, Includes the following steps: Sodium 2,5-thiophene dicarboxylate, aluminum chloride, and sodium aluminate were dissolved in water and subjected to reflux reaction. The products were then separated, purified, and dried to obtain the selective adsorption material.
2. The method for preparing the selective adsorption material according to claim 1, characterized in that: The molar ratio of sodium 2,5-thiophene dicarboxylate, aluminum chloride, and sodium aluminate is 1:0.6-0.9:0.2-0.
3.
3. The method for preparing the selective adsorption material according to claim 1, characterized in that: The sodium 2,5-thiophene dicarboxylate is prepared by a method comprising the following steps: dissolving 2,5-thiophene dicarboxylate and sodium hydroxide in water and reacting to obtain sodium 2,5-thiophene dicarboxylate.
4. The method for preparing the selective adsorption material according to claim 3, characterized in that: The molar ratio of 2,5-thiophene dicarboxylic acid to sodium hydroxide is 1:0.5 to 2.
2.
5. The method for preparing the selective adsorption material according to any one of claims 1 to 4, characterized in that: The reflux reaction time is 6h to 10h.
6. A selective adsorption material, characterized in that, It is prepared by the preparation method described in any one of claims 1 to 5.
7. The selective adsorption material according to claim 6, characterized in that: The selective adsorption material is spherical with a particle size of 80 nm to 600 nm.
8. The selective adsorption material according to claim 6 or 7, characterized in that: The selective adsorption material has a BET specific surface area of 400 m². 2 / g~650m 2 / g, pore volume 0.35cm 3 / g~0.50cm 3 / g, with a pore size of 6Å to 15Å.
9. The application of a selective adsorbent material as described in any one of claims 6 to 8 for adsorbing 5-hydroxymethylfurfural in sugar solutions.
10. A method for removing 5-hydroxymethylfurfural from a sugar solution, characterized in that, The process includes the following steps: adding the selective adsorption material according to any one of claims 6 to 8 to adsorb 5-hydroxymethylfurfural into a sugar solution, then filtering to remove the solids to obtain a purified sugar solution.