Preparation method and application of valine porous silicon modified graphene composite material
By preparing valine porous silicon modified graphene composite materials, the problem of instability of cypermethrin in alkaline and high temperature environments was solved, the adsorption capacity of pesticides was enhanced, and efficient pesticide loading effect was achieved.
Patent Information
- Application Number
- CN202311233283.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-09-22
- Publication Date
- 2025-09-16
- Estimated Expiration
- 2043-09-22
AI Technical Summary
In the existing technology, cypermethrin is unstable in alkaline and high-temperature environments, resulting in low utilization rate. Graphene is easily stacked and agglomerated, reducing the surface area. The porous silicon material has few active sites, which affects the adsorption capacity of pesticides.
Valine porous silicon modified graphene composite material was prepared by co-condensing valine organic disilicon precursor with graphene to increase active sites and improve the adsorption capacity of bifenthrin.
The loading capacity of the pesticide bifenthrin is increased, the adsorption performance is enhanced, an efficient nanopesticide preparation carrier is provided, and the utilization rate of the pesticide is improved.
Smart Images
Figure CN117482911B_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of graphene composite materials and nanopesticide preparation carriers, and particularly relates to a preparation method and application of a valine porous silicon modified graphene composite material. Background Art
[0002] Pyrethroids are a class of synthetic insecticides with key properties such as high efficacy, broad spectrum, low toxicity, and biodegradability. Bifenthrin, a new synthetic pyrethroid insecticide, boasts high pest control efficacy, a wide insecticide range, rapid action, and relative safety for the environment and humans. It is primarily used on crops such as cotton, fruits, and vegetables. However, bifenthrin is unstable and easily decomposes in alkaline and high-temperature environments, resulting in low actual utilization. Nanopesticide formulations, using nanomaterials as carriers to load pesticides, can prevent premature volatilization and improve pesticide utilization.
[0003] Graphene is a new type of material with a two-dimensional single-layer carbon atom structure. It has a large surface area, high loading capacity, easy surface modification and high chemical stability. However, in the actual preparation process, graphene is prone to stacking and agglomeration, which greatly reduces the surface area. Porous silicon material is an inorganic material synthesized from sodium silicate or tetraethyl orthosilicate. It has the advantages of high specific surface area, regular and orderly pores, high temperature resistance and acid and alkali resistance. However, simple porous silicon materials have few active sites and poor drug adsorption capacity. Usually, modification methods such as co-condensation, grafting and skeleton functionalization are used to introduce some active groups into the pores to enhance the adsorption capacity of target molecules. The composite of porous silicon material and graphene material can address the problem of easy aggregation of graphene. By selecting valine to modify the porous silicon material, the active sites in the composite material are increased, and the adsorption loading capacity of the target substance is improved.
[0004] Therefore, the preparation of valine porous silicon modified graphene composites for adsorbing bifenthrin has certain research significance and is expected to be developed into nanopesticide preparations with high loading capacity. Summary of the Invention
[0005] The present invention provides a preparation method for a valine porous silicon-modified graphene composite material for adsorbing bifenthrin, so as to solve the defects of the existing technical problems.
[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions.
[0007] On the one hand, the present application provides a method for preparing a valine porous silicon modified graphene composite material, comprising the following steps:
[0008] First, the synthesis of valine organic disilicon precursor:
[0009] Valine is used as the raw material, which is protected by di-tert-butyl dicarbonate and then amidated with N-tert-butyloxycarbonyl-ethylenediamine. The di-tert-butyl dicarbonate protection is removed under acidic conditions, and the product is reacted with 3-isocyanatepropyltriethoxysilane under inert gas to obtain a valine organic disilicone precursor.
[0010] The structural formula of the obtained valine organic disilicyl precursor is:
[0011]
[0012] Then the synthesis of valine porous silicon modified graphene composite material:
[0013] Graphene was dispersed in a mixed solution of ethanol and deionized water containing the template and sonicated for 2 hours to fully disperse it. Concentrated ammonia was then added, and a methanol solution of the valine organodisilic precursor was added dropwise to the system in a ratio determined by the graphene ratio. The reaction was stirred at room temperature for 24 hours. The resulting product was allowed to stand overnight, centrifuged, and washed multiple times with distilled water and ethanol before drying at room temperature. The product was then extracted with a mixed solution of anhydrous ethanol and hydrochloric acid for 48 hours and dried at room temperature to obtain porous silicon-modified graphene composites with varying proportions of valine.
[0014] Furthermore, the template agent is cetyltrimethylammonium bromide (CTAB).
[0015] Furthermore, the ratio of graphene to the valine organic disilicone precursor is 1:0.25 to 1:2 by mass.
[0016] Finally, the present application also provides an application of the adsorption performance of the above-mentioned valine porous silicon modified graphene composite material on bifenthrin.
[0017] The valine porous silicon modified graphene composite material obtained by the present invention exhibits high adsorption efficiency in the adsorption of bifenthrin, thereby increasing the loading amount of the pesticide.
[0018] Since the valine porous silicon modified graphene composite material obtained by the method of the present invention can efficiently adsorb bifenthrin, it provides an ideal approach for pesticide nanoformulation carrier technology. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments.
[0020] Figure 1 This is the result of the H NMR spectrum of the valine organic disilicyl precursor;
[0021] Figure 2 This is the X-ray diffraction (XRD) pattern of valine porous silicon modified graphene composite material (G@Val-PMO-1:1);
[0022] Figure 3 The nitrogen adsorption-desorption curve and pore size distribution of valine porous silicon modified graphene composite material (G@Val-PMO-1:1);
[0023] Figure 4 This is the X-ray diffraction (XRD) pattern of valine porous silicon modified graphene composite material (G@Val-PMO-1:1.2);
[0024] Figure 5 The nitrogen adsorption-desorption curve and pore size distribution of valine porous silicon modified graphene composite material (G@Val-PMO-1:1.2);
[0025] Figure 6 This is the X-ray diffraction (XRD) pattern of valine porous silicon modified graphene composite material (G@Val-PMO-1:1.4);
[0026] Figure 7 The nitrogen adsorption-desorption curve and pore size distribution of valine porous silicon modified graphene composite material (G@Val-PMO-1:1.4);
[0027] Figure 8 This is the X-ray diffraction (XRD) pattern of valine porous silicon modified graphene composite material (G@Val-PMO-1:1.6);
[0028] Figure 9 The nitrogen adsorption-desorption curve and pore size distribution of the valine porous silicon modified graphene composite material (G@Val-PMO-1:1.6); the X-ray diffraction (XRD) pattern of the methionine-tyrosine bifunctional porous material containing 25% methionine;
[0029] Figure 10 Schematic diagram of the preparation process flow of valine porous silicon modified graphene composite materials. DETAILED DESCRIPTION
[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.
[0031] Example 1: Preparation of valine organic disiloxane.
[0032] (1) Synthesis of N-tert-Butoxycarbonylvaline ethylenediamine: 5.84 g of valine was dissolved in 50 mL of 1 M sodium hydroxide solution. 50 mL of a tetrahydrofuran solution of 11.87 g of di-tert-butyl dicarbonate was slowly added to the solution under ice bath. After stirring at room temperature overnight, the solution was evaporated under reduced pressure and the solvent was evaporated to dryness. The pH value was adjusted to 2 with 1 M hydrochloric acid. The solution was extracted with ethyl acetate and the organic phase was dried over anhydrous sodium sulfate to obtain N-tert-Butoxycarbonylvaline. 10.21 g of N-tert-Butoxycarbonylvaline was dissolved in 100 mL of anhydrous tetrahydrofuran, 9.66 g of dicyclohexylcarbodiimide and 7.5 g of N-tert-Butoxycarbonyl-ethylenediamine were added, and the solution was stirred at room temperature under argon protection for 24 h. After completion, the solution was evaporated under reduced pressure at 60 ° C and purified by silica gel column chromatography to obtain white solid N-tert-Butoxycarbonylvaline ethylenediamine. (2) 10.71g of N-tert-butyloxycarbonyl valine ethylenediamine was dissolved in 50mL of anhydrous methanol, 3ml of acetyl chloride solution was added, and the mixture was reacted at room temperature for 3h. After the reaction was completed, the solvent and acetyl chloride were removed by distillation under reduced pressure. The above product was dissolved in 50mL of anhydrous tetrahydrofuran, 4mL of triethylamine was added, and 6.38g of 3-isocyanate propyltriethoxysilane (IPTES) was slowly added dropwise. Under argon protection, the mixture was stirred at room temperature and reacted for 24h. The mixture was distilled under reduced pressure, washed with n-hexane, filtered, and dried to obtain a white solid as a valine organic disilicone precursor. Figure 1 , NMR spectrum determination results: 1H NMR (400MHz, DMSO-d6) δ7.98 (s, 1H), 6.12 (t, J = 5.7Hz, 1H), 5.99–5.90 (m, 2H), 5.82 (d, J = 4.8Hz, 1H), 3.95 (dd, J = 8.9, 5.9Hz, 1H), 3.75 (q, J = 7.0Hz, 12H), 3.02 (d, J = 2 0.0Hz, 4H), 2.95 (q, J=6.7Hz, 4H), 1.86 (dq, J=13.4, 6.7Hz, 1H), 1.41 (dd, J=9.9, 6 .6Hz, 4H), 1.16 (t, J=7.0Hz, 18H), 0.81 (dd, J=13.6, 6.7Hz, 6H), 0.57–0.49 (m, 4H).
[0033] Example 2: Preparation of 1:1 valine porous silicon modified graphene composite material (G@Val-PMO-1:1).
[0034] Step (1) Dissolve 0.3 g of the template agent hexadecyltrimethylammonium bromide (CTAB) in 50 ml of deionized water and 30 ml of anhydrous ethanol at room temperature.
[0035] Step (2) Graphene is ultrasonically dispersed in a template ethanol-deionized water solution, 2 mL of concentrated ammonia is added, and according to the mass ratio of graphene to valine organic disilazane precursor of 1:1, 0.2 g of valine organic disilazane precursor dissolved in methanol is slowly added to the system under vigorous stirring, and the reaction is carried out at room temperature for 24 hours, and the mixture is allowed to stand overnight, centrifuged, and washed with distilled water and ethanol several times, and dried at room temperature. The obtained material is placed in a Soxhlet extractor, 300 mL of anhydrous ethanol and 6 mL of a mixed solution of hydrochloric acid are added, extracted for 48 hours, and dried at room temperature to obtain a 1:1 valine porous silicon modified graphene composite material (G@Val-PMO-1:1).
[0036] Step (3) 0.1 g of a 1:1 valine porous silicon modified graphene composite material (G@Val-PMO-1:1) was dispersed in 20 mL of a 1 mg / mL bifenthrin solution and shaken in a shaker at 30° C. in the dark for 24 hours. Subsequently, the mixture was filtered, and the solid was dried in the dark at room temperature. The concentration of bifenthrin in the filtrate was measured by ultraviolet spectrophotometry using the absorbance at the maximum absorption wavelength of 210 nm. The adsorption capacity of the composite material for bifenthrin was calculated using a standard curve equation to be 37.7 mg / g.
[0037] Figure 2 The XRD pattern of the 1:1 valine porous silicon modified graphene composite material (G@Val-PMO-1:1) obtained by the present embodiment is as follows: Figure 2 It can be seen that there are three strong diffraction peaks at diffraction angles of 2.3, 20.78, and 42.6, which are the (d100) crystal plane diffraction peak, the graphene stacking (d101), and the (d103) peaks, indicating that the composite material obtained by the co-condensation method of graphene and valine organic disilicon precursor contains mesoporous and graphene structural units.
[0038] Figure 3 The nitrogen adsorption-desorption curve and pore size distribution of the valine porous silicon modified graphene composite material (G@Val-PMO-1:1) obtained by the present embodiment are as follows: Figure 3 As can be seen from the figure, the composite material belongs to type IV. Capillary condensation occurs in the range of P / P0 from 0.45 to 0.99, showing an H4-type hysteresis loop. As can be seen from the pore size distribution diagram, the mesopore diameter is around 3.5 nm.
[0039] Example 3: Preparation of 1:1.2 valine porous silicon modified graphene composite material (G@Val-PMO-1:1.2).
[0040] The implementation step (1) is the same as the step (1) of Example 2.
[0041] Step (2) is substantially the same as step (2) of Example 2, except that the mass ratio of graphene to the added valine organic disilicone precursor is 1:1.2.
[0042] Step (3) is basically the same as step (3) of Example 2, except that the adsorption capacity of 1:1.2 valine porous silicon modified graphene composite material for bifenthrin is 42.2 mg / g.
[0043] Figure 4 The XRD pattern of the 1:1.2 valine porous silicon modified graphene composite material (G@Val-PMO-1:1.2) obtained by this embodiment method is as follows: Figure 4 It can be seen that there are three strong diffraction peaks at diffraction angles of 2.3, 20.78, and 42.6, which are the (d100) crystal plane diffraction peak, the graphene stacking (d101), and the (d103) peaks, indicating that the composite material obtained by the co-condensation method of graphene and valine organic disilicon precursor contains mesoporous and graphene structural units.
[0044] Figure 5 The nitrogen adsorption-desorption curve and pore size distribution of the valine porous silicon modified graphene composite material (G@Val-PMO-1:1.2) obtained by this embodiment method are as follows: Figure 5 As can be seen from the figure, the composite material belongs to type IV, and capillary condensation occurs in the range of P / P0 of 0.45-0.99, showing an H4-type hysteresis loop. As can be seen from the pore size distribution diagram, the mesopore diameter is around 3.6nm.
[0045] Example 4: Preparation of 1:1.4 valine porous silicon modified graphene composite material (G@Val-PMO-1:1.4).
[0046] Steps (1) and (2) are the same as step (1) of Example 2.
[0047] Step (2) is substantially the same as step (2) of Example 2, except that the mass ratio of graphene to the added valine organic disilicone precursor is 1:1.4.
[0048] Step (3) is basically the same as step (3) of Example 2, except that the adsorption capacity of 1:1.2 valine porous silicon modified graphene composite material for bifenthrin is 43.6 mg / g.
[0049] Figure 6 The XRD pattern of the 1:1.4 valine porous silicon modified graphene composite material (G@Val-PMO-1:1.4) obtained by this embodiment method is as follows: Figure 6It can be seen that there are three strong diffraction peaks at diffraction angles of 2.3, 20.78, and 42.6, which are the (d100) crystal plane diffraction peak, the graphene stacking (d101), and the (d103) peaks, indicating that the composite material obtained by the co-condensation method of graphene and valine organic disilicon precursor contains mesoporous and graphene structural units.
[0050] Figure 7 The nitrogen adsorption-desorption curve and pore size distribution of the valine porous silicon modified graphene composite material (G@Val-PMO-1:1.4) obtained by this embodiment method are as follows: Figure 7 As can be seen from the figure, the composite material belongs to type IV, and capillary condensation occurs in the range of P / P0 of 0.45-0.99, showing an H4-type hysteresis loop. As can be seen from the pore size distribution diagram, the mesopore diameter is around 3.6nm.
[0051] Example 5: Preparation of 1:1.6 valine porous silicon modified graphene composite material (G@Val-PMO-1:1.6).
[0052] Steps (1) and (2) are the same as step (1) of Example 2.
[0053] Step (2) is substantially the same as step (2) of Example 2, except that the mass ratio of graphene to the added valine organic disilicone precursor is 1:1.6.
[0054] Step (3) is basically the same as step (3) of Example 2, except that the adsorption capacity of 1:1.6 valine porous silicon modified graphene composite material for bifenthrin is 36.8 mg / g.
[0055] Figure 8 The XRD pattern of the 1:1.6 valine porous silicon modified graphene composite material (G@Val-PMO-1:1.6) obtained by the present embodiment is as follows: Figure 8 It can be seen that there are two strong diffraction peaks at diffraction angles of 2.3 and 20.78, which are the (d100) crystal plane diffraction peak and the graphene stacking (d101) peak, indicating that the composite material obtained by the co-condensation method of graphene and valine organic disilicon precursor contains mesoporous and graphene structural units.
[0056] Figure 9 The nitrogen adsorption-desorption curve and pore size distribution of the valine porous silicon modified graphene composite material (G@Val-PMO-1:1.6) obtained by this embodiment method are as follows: Figure 9As can be seen from the figure, the composite material belongs to type IV. Capillary condensation occurs in the range of P / P0 from 0.45 to 0.99, showing an H4-type hysteresis loop. As can be seen from the pore size distribution diagram, the mesopore diameter is around 3.5 nm.
[0057] In summary, increasing the valine organodisilic precursor content reduces the ordered structure and orderliness of the material, and the adsorption of bifenthrin also decreases slightly. However, the material still retains the mesoporous pore structure characteristics and has good adsorption performance.
[0058] Figure 10 Schematic diagram of the preparation process flow of valine porous silicon modified graphene composite materials.
[0059] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.
Claims
1. Application of a valine porous silicon modified graphene composite material in adsorption of bifenthrin, characterized in that: The preparation method of the composite material comprises the following steps: 1) Valine was protected with di-tert-butyl dicarbonate and amidated with N-tert-butyloxycarbonylethylenediamine. Under acidic conditions and inert gas atmosphere, it reacted with 3-isocyanatopropyltriethoxysilane to obtain the valine organodisilic precursor. 2) Graphene and a template solution of ethanol-deionized water were mixed and ultrasonically dispersed. After adding concentrated ammonia, the valine organic disilicyl precursor was added dropwise according to the ratio of valine to graphene. The mixture was reacted in a water bath at room temperature for 24 hours, allowed to stand overnight, and then centrifuged, washed, filtered, and dried. 3) extracting the product in anhydrous ethanol and hydrochloric acid solution using a Soxhlet extractor and drying at room temperature to obtain a valine porous silicon-modified graphene composite material; The ratio of graphene to valine organic disilicon precursor is 1:0.25 to 1:2 by mass; The structural formula of the valine organic disilicone precursor is as follows: 。 2. The use according to claim 1, characterized in that The template agent is hexadecyltrimethylammonium bromide.