A starch-based composite aerogel preparation method and heavy metal adsorption application thereof
Patent Information
- Application Number
- CN202611184113.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-08-06
- Publication Date
- 2026-09-15
Smart Images
Figure CN122745802A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of biocomposite aerogels, and specifically relates to a starch-based aerogel, its preparation method and uses, which belongs to the field of aerogels. Background Technology
[0002] Aerogels exhibit significant advantages in the adsorption of heavy metal ions (HMIs) due to their unique three-dimensional porous structure and large specific surface area. Common HMI adsorption aerogels include silica aerogels (adsorption capacity 50-200 mg g / g). -1 ), carbon aerogel (200-300 mg g) -1 ) and biomass aerogels (200-500 mg g) -1 Among them, natural biomass materials exhibit excellent adsorption performance for HMI, possessing advantages such as large adsorption capacity, strong selective adsorption capacity for different HMIs, and easy regeneration after acid desorption. Therefore, the development of bio-based composite aerogels with both high adsorption capacity and selectivity is of great significance for the practical treatment of HMI pollution.
[0003] Based on this, this invention starts with molecular structure design, using starch (HPS) and k-carrageenan (k-CA) as the gel matrix, and introduces EDTA-Ca as the adsorption functional unit to prepare a starch-based composite hydrogel (SKE hydrogel). Further, its aerogel (SKE aerogel) is prepared using a freeze-drying method to achieve efficient HMI adsorption. By controlling the EDTA-Ca content (10-50 wt.%), the crosslinking density and HMI binding sites are effectively controlled, thereby improving the structural stability and adsorption capacity of the aerogel. The adsorption of Cu by SKE aerogel is demonstrated. 2+ Taking an example, by fitting a kinetic model and an adsorption isotherm model, the main adsorption mechanism of SKE aerogel was confirmed. This invention aims to provide experimental basis for designing starch-based materials with high HMI adsorption performance. Summary of the Invention
[0004] The main objective of this invention is to provide a method for preparing starch-based composite aerogels and their application in heavy metal adsorption. This invention provides some assistance for the adsorption of HMI content in traditional Chinese medicine and seafood in the future, expands the application potential of biomass materials, and provides some reference for the design of similar functional materials.
[0005] This invention includes the following steps: (1) Preparation of starch gelatinization solution Add HPS to distilled water and stir for a period of time to make a gelatinized solution. After the gelatinization is complete, store it at high temperature for later use. (2) Preparation of starch-based composite hydrogel Add disodium calcium ethylenediaminetetraacetate (EDTA-Ca) and k-CA to the gelatinization solution and stir until the film-forming solution is completely defoamed; cast the composite solution onto a culture dish and let it stand at room temperature to obtain the composite hydrogel.
[0006] Preparation of starch-based composite aerogel Starch-based composite hydrogels were dried to obtain starch-based composite aerogels; In step (1), the starch is one or more of potato starch, corn starch, pea starch, purple sweet potato starch, and rice starch, and its mass is 2 to 20 g. In step (1), the gelatinization temperature during the heating process is 60-120℃, the heating rate is 0.1-10 K / min, the stirring rate is 100-800 rpm, and the gelatinization time is 10-300 min. In step (2), the mass of EDTA-Ca is 0.2–20 g, the mass of k-CA is 2–20 g, and the solid content is 5–90%. In step (2), the reaction temperature is 60-200℃, the heating rate is 1-10 K / min, the stirring rate is 100-800 rpm, and the reaction time is 10-500 min. In step (3), the drying method is freeze drying or supercritical drying, followed by freezing in liquid nitrogen for 1 to 10 minutes, and finally freeze drying at -80 to -20°C for 1 to 10 hours.
[0007] This invention provides a starch-based composite aerogel, prepared according to the above method.
[0008] This invention also provides the application of the above-mentioned starch-based composite film in heavy metal adsorption. Specifically, CuSO4 is accurately dissolved in distilled water to prepare 0.5–5 g / L of the film. -1 Ionic solutions of CuSO4 were prepared in concentrations ranging from 1 to 1000 ppm by dilution. The absorbance of CuSO4 solutions of different concentrations at a wavelength of λ = 559 nm was measured using a UV-Vis spectrophotometer. A reference curve for the UV absorption spectrum of the CuSO4 solution was plotted by data fitting, with the fitting equation being Abs = 0.00583C + 0.0223. SKE aerogel was added to the prepared CuSO4 solutions as an adsorbent and oscillated at 100 rpm. The adsorption capacity of the SKE aerogel was calculated by measuring the absorbance of the remaining CuSO4 solution at the same wavelength and comparing it with the reference curve of the CuSO4 solution. All adsorption experiments were repeated three times, and the average value was taken.
[0009] The beneficial effects of this invention are reflected in the fact that the starch-based composite aerogel prepared by this invention is obtained from biodegradable materials HPS and k-CA. Specifically, the synergistic effect of HPS and EDTA-Ca on HMI enables the composite membrane to possess high sensitivity, achieving high sensitivity for Cu. 2+ The highly efficient adsorption provides a new approach for the adsorption of heavy metal ions in traditional Chinese medicine and seafood.
[0010] The present invention does not involve high-energy-consuming processing methods in the preparation of composite aerogels, and the process is simple and easy to industrialize.
[0011] This invention utilizes the complexation effect between HPS and EDTA-Ca to make the matrix more tightly connected, without chemical crosslinking, and has good thermodynamic properties and low cost.
[0012] This invention realizes the full-chain application of starch-based gel materials in the field of HMI management, namely "detection before removal".
[0013] This invention incorporates the traditional detoxifying drug EDTA-Ca, expanding its future market applications. Attached Figure Description
[0014] Figure 1 The Fourier transform infrared spectrum of the starch-based composite aerogel corresponds to Example 1; Figure 2 The flowchart shows the preparation process of starch-based composite aerogel, corresponding to Example 2; Figure 3 The X-ray diffraction pattern of the starch-based composite aerogel corresponds to Example 3; Figure 4 The image shows the scanning electron microscope results of the starch-based composite aerogel, corresponding to Example 4; Figure 5 The N2 adsorption / desorption curves for the starch-based composite aerogel correspond to Example 5. Figure 6 The water contact angle and water absorption rate of the starch-based composite aerogel are shown in Example 6; Figure 7 , 8 Adsorption of Cu by starch-based composite aerogel 2+ The PFO, PSO, Langmuir, and Freundlich models correspond to Example 7. Detailed Implementation
[0015] The present invention will be further described below with reference to embodiments: Unless otherwise specified, all raw materials and equipment used in the following embodiments are commercially available products known in the art. Example 1
[0016] A method for preparing starch / carrageenan composite aerogel includes the following steps: (1) Preparation of starch gelatinization solution Take 10 g of HPS and add it to 50 mL of distilled water. Stir at 150 rpm and react for 2 h to prepare a gelatinized solution. After the reaction is complete, store it at high temperature for later use. (2) Preparation of starch-based composite hydrogel Add 5 g of k-CA to the gelatinization solution, stir at 350 rad / min for 2 h, then stir at 100 rpm for 6 h until the above film-forming solution is completely defoamed. Cast the solution onto a culture dish, then cast the composite solution onto a culture dish, and let it stand at room temperature to obtain the composite hydrogel.
[0017] (3) Preparation of starch-based composite aerogel The starch-based composite hydrogel was dried to obtain a starch-based composite aerogel. The experiment was completed, and the sample was labeled SK.
[0018] like Figure 1 The Fourier transform infrared spectrum of the starch-based composite aerogel is shown. Example 2
[0019] A method for preparing starch / carrageenan / disodium calcium EDTA composite aerogel includes the following steps: (1) Preparation of starch gelatinization solution Take 10 g of HPS and add it to 50 mL of distilled water. Stir at 150 rpm and react for 2 h to prepare a gelatinized solution. After the reaction is complete, store it at high temperature for later use. (2) Preparation of starch-based composite film Add 5 g of k-CA and 2%wt of EDTA-Ca to the gelatinization solution, stir at 350 rad / min for 2 h, stir at 100 rpm for 6 h until the above film-forming solution is completely defoamed, and then cast it onto a culture dish. Cast the composite solution onto the culture dish and let it stand at room temperature to obtain the composite hydrogel.
[0020] (3) Preparation of starch-based composite aerogel The starch-based composite hydrogel was dried to obtain a starch-based composite aerogel. The experiment was completed, and the sample was labeled SKE-1.
[0021] like Figure 2 The preparation process of starch-based composite aerogels was demonstrated. Example 3
[0022] A method for preparing starch / carrageenan / disodium calcium EDTA composite aerogel includes the following steps: (1) Preparation of starch gelatinization solution Take 10 g of HPS and add it to 50 mL of distilled water. Stir at 150 rpm and react for 2 h to prepare a gelatinized solution. After the reaction is complete, store it at high temperature for later use. (2) Preparation of starch-based composite film Add 5 g of k-CA and 4%wt of EDTA-Ca to the gelatinization solution, stir at 350 rad / min for 2 h, stir at 100 rpm for 6 h until the above film-forming solution is completely defoamed, and cast it onto a culture dish. Cast the composite solution onto the culture dish and let it stand at room temperature to obtain the composite hydrogel.
[0023] (3) Preparation of starch-based composite aerogel The starch-based composite hydrogel was dried to obtain a starch-based composite aerogel. The experiment was completed, and the sample was labeled SKE-2.
[0024] like Figure 3 The X-ray diffraction pattern of the starch-based composite aerogel is shown. Example 4
[0025] A method for preparing starch / carrageenan / disodium calcium EDTA composite aerogel includes the following steps: (1) Preparation of starch gelatinization solution Take 10 g of HPS and add it to 50 mL of distilled water. Stir at 150 rpm and react for 2 h to prepare a gelatinized solution. After the reaction is complete, store it at high temperature for later use. (2) Preparation of starch-based composite film Add 5 g of k-CA and 6%wt of EDTA-Ca to the gelatinization solution, stir at 350 rad / min for 2 h, stir at 100 rpm for 6 h until the above film-forming solution is completely defoamed, and then cast it onto a culture dish. Cast the composite solution onto the culture dish and let it stand at room temperature to obtain the composite hydrogel.
[0026] (3) Preparation of starch-based composite aerogel The starch-based composite hydrogel was dried to obtain a starch-based composite aerogel. The experiment was completed, and the sample was labeled SKE-3.
[0027] like Figure 4 The scanning electron microscope (SEM) results of the starch-based composite aerogel are shown. Example 5
[0028] A method for preparing starch / carrageenan / disodium calcium EDTA composite aerogel includes the following steps: (1) Preparation of starch gelatinization solution Take 10 g of HPS and add it to 50 mL of distilled water. Stir at 150 rpm and react for 2 h to prepare a gelatinized solution. After the reaction is complete, store it at high temperature for later use. (2) Preparation of starch-based composite film Add 5 g of k-CA and 8%wt of EDTA-Ca to the gelatinization solution, stir at 350 rad / min for 2 h, stir at 100 rpm for 6 h until the above film-forming solution is completely defoamed, and then cast it onto a culture dish. Cast the composite solution onto the culture dish and let it stand at room temperature to obtain the composite hydrogel.
[0029] (3) Preparation of starch-based composite aerogel The starch-based composite hydrogel was dried to obtain a starch-based composite aerogel. The experiment was completed, and the sample was labeled SKE-4.
[0030] like Figure 5 The N2 adsorption / desorption curves of starch-based composite aerogels are shown. Example 6
[0031] A method for preparing starch / carrageenan / disodium calcium EDTA composite aerogel includes the following steps: (1) Preparation of starch gelatinization solution Take 10 g of HPS and add it to 50 mL of distilled water. Stir at 150 rpm and react for 2 h to prepare a gelatinized solution. After the reaction is complete, store it at high temperature for later use. (2) Preparation of starch-based composite film Add 5 g of k-CA and 10% wt of EDTA-Ca to the gelatinization solution, stir at 350 rad / min for 2 h, stir at 100 rpm for 6 h until the above film-forming solution is completely defoamed, and then cast it onto a culture dish. Cast the composite solution onto the culture dish and let it stand at room temperature to obtain the composite hydrogel.
[0032] (3) Preparation of starch-based composite aerogel The starch-based composite hydrogel was dried to obtain a starch-based composite aerogel. The experiment was completed, and the sample was labeled SKE-5.
[0033] like Figure 6 The water contact angle and water absorption rate of starch-based composite aerogels were demonstrated. Example 7
[0034] A method for heavy metal adsorption using starch / carrageenan / disodium calcium EDTA composite aerogel includes the following steps: CuSO4 was accurately dissolved in distilled water to prepare a solution of 0.5–5 g / L. -1Ionic solutions of CuSO4 were prepared in concentrations ranging from 1 to 1000 ppm by dilution. The absorbance of CuSO4 solutions of different concentrations at a wavelength of λ = 559 nm was measured using a UV-Vis spectrophotometer. A reference curve for the UV absorption spectrum of the CuSO4 solution was plotted by data fitting, with the fitting equation being Abs = 0.00583C + 0.0223. SKE aerogel was added to the prepared CuSO4 solutions as an adsorbent and oscillated at 100 rpm. The adsorption capacity of the SKE aerogel was calculated by measuring the absorbance of the remaining CuSO4 solution at the same wavelength and comparing it with the reference curve of the CuSO4 solution. All adsorption experiments were repeated three times, and the average value was taken.
[0035] like Figure 7 and Figure 8 Demonstrates the adsorption of Cu by starch-based composite aerogel 2+ The PFO, PSO, Langmuir and Freundlich models.
[0036] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A method for preparing a starch-based composite aerogel, characterized in that, Includes the following steps: (1) Preparation of starch (HPS) gelatinized solution HPS was subjected to a gelatinization reaction to prepare a gelatinized solution, which was then stored at high temperature for later use. (2) Preparation of starch-based composite hydrogel EDTA-Ca and k-carrageenan (k-CA) were added to a gelatinization solution, stirred to defoam, and allowed to stand to obtain a composite hydrogel. Preparation of starch-based composite aerogel The hydrogel was dried to obtain a starch-based composite aerogel.
2. The method for preparing starch-based composite aerogel as described in claim 1, characterized in that, In step (1), the starch is one or more of potato starch, corn starch, pea starch, purple sweet potato starch, and rice starch, and its mass is 2 to 20 g.
3. The method for preparing starch-based composite aerogel as described in claim 1, characterized in that, In step (1), the gelatinization temperature during the heating process is 60-120℃, the heating rate is 0.1-10 K / min, the stirring rate is 100-800 rpm, and the gelatinization time is 10-300 min.
4. The method for preparing starch-based composite aerogel as described in claim 1, characterized in that, In step (2), the mass of EDTA-Ca is 0.2–20 g, the mass of k-CA is 2–20 g, and the solid content is 5–90%.
5. The method for preparing starch-based composite aerogel as described in claim 1, characterized in that, In step (2), the reaction temperature is 60-200℃, the heating rate is 1-10 K / min, the stirring rate is 100-800 rpm, and the reaction time is 10-500 min.
6. The method for preparing starch-based composite aerogel as described in claim 1, characterized in that, In step (3), the composite hydrogel is freeze-dried or supercritically dried, then placed in liquid nitrogen for 1 to 10 min, and finally freeze-dried at -80 to -20℃ for 1 to 10 h.
7. A starch-based composite film, characterized in that, Prepared according to the method of any one of claims 1 to 6.
8. The application of the starch-based composite membrane as described in claim 7 in the adsorption of heavy metals.