Oxygen / nitrogen-enriched organic molecule functionalized graphene oxide composite material as well as preparation and application thereof

Abstract

The invention discloses an oxygen / nitrogen-rich organic molecule functionalized graphene oxide composite material as well as preparation and application thereof, and relates to the field of nano composite materials. The composite material comprises a substrate and oxygen / nitrogen-rich organic molecules which are connected through a grafting reaction. The preparation method comprises the following steps: S1, uniformly dispersing graphene oxide in anhydrous N, N-dimethylformamide (DMF) to obtain a graphene oxide dispersion liquid; and S2, uniformly mixing the obtained graphene oxide dispersion liquid with D-galactosamine hydrochloride, and carrying out amidation reaction under a catalytic condition to obtain the oxygen / nitrogen-rich organic molecule functionalized graphene oxide composite material. The composite material can be used as an adsorbent for adsorbing phenolic pollutants, shows excellent adsorption selectivity to 1-naphthol, can efficiently enrich and separate low-concentration 1-naphthol, has good reusability, and has wide application prospects in the adsorption separation process of wastewater treatment.

Description

Technical Field

[0001] This invention relates to the field of nanocomposite materials, specifically to an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material, its preparation, and its application. Background Technology

[0002] 1-Naphthol (1-NP) is a typical polycyclic aromatic hydrocarbon (PAH) derivative with a hydroxyl substituent in its chemical structure. It has wide applications in industrial production, including dyes, pesticides, plastics, and pharmaceuticals. 1-NP easily enters the environment through industrial wastewater discharge or accidental leaks, posing a threat to ecosystems. Due to its potential environmental and health risks, 1-NP has been listed as a priority pollutant by the U.S. Environmental Protection Agency (EPA) and the European Union. As a typical persistent organic pollutant, 1-NP is difficult to eliminate naturally from the environment through biodegradation. Therefore, effective removal of 1-NP from wastewater is particularly important. There are many conventional technologies for removing phenolic pollutants from wastewater, such as extraction, membrane filtration, photocatalysis, and adsorption. Among these technologies, adsorption has been extensively studied and widely applied in practice due to its advantages such as simple operation, easy adjustment, high efficiency, low cost, and time and labor savings.

[0003] Graphene oxide (GO) and its derivatives, as novel sheet-like carbon nanomaterials, are considered potential adsorbents for removing phenolic pollutants from water due to their unique layered structure, abundant oxygen-containing functional groups, and easily tunable surface functionalization properties. However, GO's excellent dispersibility makes it difficult to separate after adsorption, limiting its further application in wastewater treatment. GO possesses numerous hydroxyl, epoxy, and carbonyl groups, allowing for chemical modification with appropriate functional groups to improve its chemical and physical properties. Utilizing specific molecules to chemically modify graphene oxide can not only increase the adsorption sites but also improve its separation and recovery performance, demonstrating broad application prospects in the field of adsorption separation. Summary of the Invention

[0004] Therefore, this invention proposes an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material, its preparation, and its application. Through the amidation reaction of ammonium ions on D-galactosamine hydrochloride molecules with carboxyl groups on the surface of graphene oxide, a structurally stable graphene oxide-based composite material is formed, thus solving the problem in existing technologies where the graphene oxide is difficult to separate after adsorption, limiting its further application in wastewater treatment.

[0005] To achieve the above objectives, the present invention provides the following technical solution: According to a first aspect of the present invention, an oxygen-rich / nitrogen-rich organic molecule functionalized graphene oxide composite material is provided, comprising a substrate and oxygen-rich / nitrogen-rich organic molecules, which are formed into a functionalized composite material through a grafting reaction.

[0006] Preferably, the substrate is graphene oxide, and the oxygen-rich / nitrogen-rich organic molecule is D-galactosamine hydrochloride.

[0007] According to a second aspect of the present invention, a method for preparing an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material is provided, wherein the method comprises the following steps: S1: Graphene oxide is uniformly dispersed in anhydrous N,N-dimethylformamide to obtain a graphene oxide dispersion. S2: The graphene oxide dispersion obtained in step S1 is uniformly mixed with D-galactosamine hydrochloride to obtain a reactant. An amidation reaction is carried out under anhydrous catalytic conditions. The resulting product is repeatedly washed with ethanol and ultrapure water and then freeze-dried to obtain a composite material.

[0008] Furthermore, the graphene oxide is a dry powder solid, and the D-galactosamine hydrochloride has a purity higher than 95%.

[0009] Further, 0.8~1.2g of graphene oxide, 70~160mL of anhydrous N,N-dimethylformamide and 0.9~3g of D-galactosamine hydrochloride were ultrasonically dispersed and mixed evenly.

[0010] Further, in step S2, the anhydrous catalytic conditions use 0.9~2.5g of O-(7-azabenzotriazol-1-yl)-N,N,N',N'-tetramethylurea hexafluorophosphate (HATU) and 2.0~4.0mL of N,N-diisopropylethylamine as catalysts, and the catalysts and reactants are ultrasonically stirred until they are uniformly mixed.

[0011] Furthermore, in step S2, the anhydrous catalytic conditions are achieved by a moisture-proof reflux device, and the reaction is carried out by heating and reflux at 120℃~180℃ for 15~38h.

[0012] Further, in step S2, the amidation reaction is carried out under continuous stirring. After the reaction is completed, the reaction system is allowed to cool naturally to room temperature. The product is separated by vacuum filtration. The filter cake is washed repeatedly with 80-180 mL of ethanol and ultrapure water, and the washing is repeated at least three times. The solids remaining on the filter membrane are collected.

[0013] According to a third aspect of the present invention, an application is provided for the selective adsorption and separation of dyes and phenolic compounds in aqueous solutions using an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material.

[0014] Furthermore, the dyes include methylene blue (MB) and alizarin yellow (AYR), and the phenolic compounds include 1-naphthol (1-NP), p-nitrophenol (PNP), m-nitrophenol (MNP), tert-butylhydroquinone (TBHQ), and hydroquinone (HQ), with an adsorption concentration of 30~60 mg / L.

[0015] The above-described solution of the present invention has the following advantages: In this invention, graphene oxide and D-galactosamine hydrochloride are synthesized into a structurally stable composite material via an amidation reaction under catalytic conditions. This material is easily separated and, due to the differences in interaction forces with different adsorbates, can selectively adsorb phenolic pollutants. Experimental results show that the composite material has a significant adsorption effect on 1-naphthol, while its adsorption capacity for dyes is weak, thus achieving the adsorption and removal of 1-naphthol from aqueous solutions. Furthermore, the composite material exhibits stable physicochemical properties and good reusability, reducing the cost of the adsorption process and providing an efficient and economical solution for related fields. Attached Figure Description

[0016] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0017] The structures, proportions, sizes, etc. illustrated in this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0018] Figure 1 A comparison of the adsorption capacities of different dyes and phenolic compounds in an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material provided by this invention; Figure 2 The effect of an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material on the adsorption effect of 1-naphthol at different adsorption times is shown in the figure provided by this invention. Figure 3 The figure shows the effect of an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material on the adsorption effect of 1-naphthol under different conditions, provided by this invention. Figure 3 Figure A shows the effect of an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material provided by this invention on the adsorption effect of 1-naphthol under different pH conditions. Figure 3 B is a graph showing the effect of an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material provided by this invention on the adsorption effect of 1-naphthol under different adsorption-desorption cycles; Figure 4 Fourier transform infrared spectra of different materials in an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material provided by this invention; wherein Figure 4 A shows the Fourier transform infrared spectra of graphene oxide and the oxygen-rich / nitrogen-functionalized graphene oxide composite material before and after adsorption of 1-naphthol. Figure 4 B is the Fourier transform infrared spectrum of D-galactosamine hydrochloride molecule; Figure 5 Scanning electron microscope (SEM) images of graphene oxide and oxygen-rich / nitrogen-enriched organic molecule-functionalized graphene oxide composite materials before and after adsorption of 1-naphthol provided by this invention; wherein Figure 5 A is a SEM image of graphene oxide. Figure 5 B is a SEM image (scale bar 50 μm) of the oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material. Figure 5 C is a SEM image of the oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material after adsorption of 1-naphthol; Figure 6 This is a scanning electron microscope image (scale bar 90 μm) of an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material provided for this invention. Figure 7 This is an elemental mapping diagram of an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material provided by the present invention, wherein... Figure 7 B Figure 7 C and Figure 7 D represents the element mapping diagrams for C, O, and N, respectively; Figure 8 This is an EDS energy level spectrum of an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material provided for this invention. Detailed Implementation

[0019] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] The usage process of this invention embodiment is as follows: According to a first aspect of the present invention, an oxygen-rich / nitrogen-rich organic molecule functionalized graphene oxide composite material is provided, comprising a substrate and oxygen-rich / nitrogen-rich organic molecules, which are formed into a functionalized composite material through a grafting reaction.

[0021] The substrate is graphene oxide, and the oxygen- and nitrogen-rich organic molecule is D-galactosamine hydrochloride.

[0022] According to a second aspect of the present invention, a method for preparing an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material is provided, comprising the following steps: S1: Graphene oxide is uniformly dispersed in anhydrous N,N-dimethylformamide to obtain a graphene oxide dispersion. S2: The graphene oxide dispersion obtained in step S1 is uniformly mixed with D-galactosamine hydrochloride to obtain a reactant. An amidation reaction is carried out under anhydrous catalytic conditions. The resulting product is repeatedly washed with ethanol and ultrapure water and then freeze-dried to obtain a composite material.

[0023] Among them, graphene oxide is a dry powder solid, and D-galactosamine hydrochloride has a purity of over 95%.

[0024] In this process, 0.8-1.2g of graphene oxide, 70-160mL of anhydrous N,N-dimethylformamide, and 0.9-3g of D-galactosamine hydrochloride are ultrasonically dispersed and mixed evenly.

[0025] In step S2, the anhydrous catalytic conditions use 0.9-2.5 g of O-(7-azabenzotriazol-1-yl)-N,N,N',N'-tetramethylurea hexafluorophosphate (HATU) and 2.0-4.0 mL of N,N-diisopropylethylamine as catalysts, and the catalysts and reactants are ultrasonically stirred until they are uniformly mixed.

[0026] In step S2, the anhydrous catalytic conditions are achieved by a moisture-proof reflux device, and the reaction is carried out by heating and reflux at 120℃~180℃ for 15~38h.

[0027] In step S2, the amidation reaction is carried out under continuous stirring. After the reaction is completed, the reaction system is allowed to cool naturally to room temperature. The product is separated by vacuum filtration. The filter cake is washed repeatedly with 80-180 mL of ethanol and ultrapure water, and the washing is repeated at least three times. The solid remaining on the filter membrane is collected.

[0028] Example 1 The preparation of an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material in this example is as follows: Weigh 1.0 g of graphene oxide into a 250 mL round-bottom flask, add 120 mL of DMF solution, and sonicate for 30 min to ensure that the graphene oxide is uniformly dispersed in anhydrous N,N-dimethylformamide solution.

[0029] Add 1.9236 g of HATU, 3.705 mL of N,N-diisopropylethylamine, and 2.0 g of D-galactosamine hydrochloride sequentially to the graphene oxide dispersion, and stir continuously until the organic molecules no longer agglomerate. Seal the mixture and set aside for later use.

[0030] Place the round-bottom flask in a thermostatic magnetic stirrer and stir continuously at 130°C for 36 hours.

[0031] After the reaction was completed, the reaction solution was naturally cooled to room temperature, and the obtained product was filtered. The filter residue was washed repeatedly with 150 mL of ethanol and ultrapure water at least three times. The solid remaining on the filter membrane was collected and freeze-dried to obtain oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material.

[0032] Example 2 The application of an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material in this example is as follows: Weigh 5 mg of oxygen-enriched / nitrogen-enriched organic functionalized graphene oxide composite material into a 100 mL Erlenmeyer flask, add 20 mL of adsorbate solution, and incubate at 25 °C with constant shaking for 120 min. Collect the adsorbate solution after adsorption. The adsorbate is a dye or phenolic compound.

[0033] After diluting the adsorbate solution to a certain factor, the absorbance was measured using a UV-Vis spectrophotometer. The corresponding concentration was calculated using a standard curve, thereby calculating the adsorption capacity of the oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material for each adsorbate.

[0034] The oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material provided by this invention can effectively adsorb dye or phenolic compound solutions with a concentration range of 30-60 mg / L, i.e., an adsorption concentration of 30-60 mg / L. For example... Figure 1 The figure shown is a comparison of the adsorption capacities of an oxygen-rich / nitrogen-enriched organic molecular functionalized graphene oxide composite material provided by the present invention for different dyes (including MB: methylene blue and AYR: alizarin yellow) and phenolic compounds (including 1-NP: 1-naphthol, PNP: p-nitrophenol, MNP: m-nitrophenol, TBHQ: tert-butylhydroquinone and HQ: hydroquinone), where q e and q tThe figures represent the amount of substance and mass of dye or phenolic compound adsorbed per unit mass of the composite material. It can be seen that the oxygen-enriched / nitrogen-functionalized graphene oxide composite material exhibits certain adsorption effects on both dyes and phenolic compounds, with a significantly better adsorption effect on 1-naphthol than on dyes. Therefore, this composite material can be used to separate 1-naphthol from aqueous solutions for industrial wastewater treatment and environmental protection.

[0035] Example 3 The application of an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material in this example is as follows: Weigh 5 mg of oxygen-enriched / nitrogen-enriched organic molecular functionalized graphene oxide composite material into a 100 mL conical flask, add 20 mL of 1-naphthol solution, and conduct experiments at different time points (2, 5, 10, 15, 30, 60, 90, 120 and 150 min) at 25 °C, and collect the adsorbed 1-naphthol solution.

[0036] The adsorbed 1-naphthol solution obtained above was diluted to a certain factor, and the absorbance was measured using a UV-Vis spectrophotometer. The corresponding concentration was calculated using a standard curve to calculate the adsorption capacity of the composite material for the 1-naphthol solution.

[0037] like Figure 2 As shown, the amount of 1-naphthol solution adsorbed per unit mass of oxygen-enriched / nitrogen-enriched organic molecule functionalized graphene oxide composite material at different times indicates that the adsorption process of 1-naphthol by this composite material exhibits a high adsorption rate in the first 30 minutes. During this stage, 1-naphthol molecules can rapidly interact with the oxygen-enriched / nitrogen-enriched organic molecule functionalized graphene oxide composite material, and the adsorption process is extremely efficient. With the extension of adsorption time, the adsorption rate gradually slows down, indicating that the adsorption process has entered a slow adsorption stage and reaches dynamic equilibrium at 120 minutes.

[0038] Example 4 The application of an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material in this example is as follows: Adjust the pH of the 1-naphthol solution to (2-8) using 0.1 mol / L NaOH and 0.1 mol / L HCl solutions. Weigh 5 mg of oxygen-enriched / nitrogen-enriched organic molecular functionalized graphene oxide composite material into a 100 mL Erlenmeyer flask, and add 20 mL of 1-naphthol solution with different pH values ​​(3.14, 4.06, 5.09, 6.06, 7.09, 8.14, and 9.06). Incubate at 25 °C with constant temperature shaking for 120 min, and collect the adsorbed 1-naphthol solution.

[0039] The adsorbed 1-naphthol solution obtained above was diluted to a certain factor, and the absorbance was measured using a UV-Vis spectrophotometer. The corresponding concentration was calculated using a standard curve to calculate the adsorption capacity of the composite material for the 1-naphthol solution.

[0040] from Figure 3 As can be seen from the results, the oxygen-enriched / nitrogen-functionalized graphene oxide composite material exhibits good adsorption performance for 1-naphthol within the pH range of 3.14-9.06. However, at pH < 6.06, due to the abundance of -NH and -OH groups on the surface of this composite material, it is easily protonated under acidic conditions, resulting in a positive surface charge. This leads to electrostatic repulsion between the positively charged 1-naphthol and the similarly protonated 1-NP, resulting in a lower adsorption capacity. At pH 6.06, the surface protonation of the composite material is moderate, and 1-naphthol mainly exists in the form of neutral molecules. The two molecules are mainly bound by non-electrostatic forces such as hydrophobicity, hydrogen bonding, and π-π stacking interactions, thus exhibiting the highest adsorption capacity. Under higher pH conditions, the surface of the oxygen-enriched / nitrogen-functionalized graphene oxide composite material gradually undergoes deprotonation, becoming negatively charged. At this point, a small amount of 1-naphthol is also deprotonated, leading to electrostatic repulsion between the two molecules, thus slightly decreasing the adsorption capacity.

[0041] Example 5 The application of an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material in this example is as follows: Weigh 50 mg of oxygen-enriched / nitrogen-enriched organic molecular functionalized graphene oxide composite material into a 100 mL Erlenmeyer flask, add 20 mL of 10 mg / L 1-naphthol solution, and shake at 25 °C for 120 min to ensure that the adsorption process reaches equilibrium.

[0042] After adsorption, the adsorbed composite material was collected and repeatedly washed with ultrapure water. After washing, it was separated by vacuum filtration, followed by desorption experiments. During desorption, 40 mL of anhydrous ethanol was used as the desorbent, and the desorption time was consistent with the adsorption equilibrium time, both being 120 min, to ensure sufficient desorption of 1-naphthol from the surface of the oxygen-rich / nitrogen-functionalized organic molecule graphene oxide composite material. After desorption, the oxygen-rich / nitrogen-functionalized organic molecule graphene oxide composite material was washed again with ultrapure water and separated by vacuum filtration. The filtered composite material was directly used for the next adsorption-desorption cycle. The entire adsorption-desorption process was repeated 10 times.

[0043] The 1-naphthol solution after being adsorbed by the oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material during each adsorption process was collected, diluted to a certain factor, and the absorbance was measured using a UV-Vis spectrophotometer. The corresponding concentration was calculated through a standard curve to calculate the adsorption capacity of the composite material for the 1-naphthol solution.

[0044] from Figure 3 As can be seen from B, the oxygen-enriched / nitrogen-enriched organic molecule functionalized graphene oxide composite material exhibits excellent reusability. Even after 10 adsorption-desorption cycles, its removal rate of 1-NP can still reach 97.5%.

[0045] This invention employs Fourier transform infrared spectroscopy to analyze the chemical composition and bonding mechanisms of oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composites, and uses scanning electron microscopy (SEM) to observe the morphological changes of the graphene oxide raw material and composite material before and after adsorption. The adsorption results and material characterization are as follows: like Figure 4 The image shows Fourier transform infrared spectra of different materials in an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material provided by the present invention. Figure 4 A shows the Fourier transform infrared spectra of graphene oxide (GO), oxygen-enriched / nitrogen-functionalized graphene oxide composite material (GO-DGA), and oxygen-enriched / nitrogen-functionalized graphene oxide composite material after adsorption of 1-naphthol (GO-DGA-1-NP). Figure 4 B is the Fourier transform infrared spectrum of D-galactosamine hydrochloride molecule. It can be seen that the amidation of the oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material is successful. Compared with the original graphene oxide, the composite material exhibits a higher optical density at 1670.36 cm⁻¹. -1 A distinct amide bond characteristic absorption peak appeared at 1447.49 cm⁻¹. -1 A new CN bond stretching vibration peak was observed, indicating that D-galactosamine hydrochloride molecules were successfully grafted onto the graphene oxide surface via an amidation reaction. Furthermore, after adsorption of 1-naphthol (1-NP), the characteristic peaks of the OH / NH and C=C bonds in the composite material showed significant shifts, indicating the presence of hydrogen bonds and π-π stacking interactions between the composite material and the 1-NP molecules.

[0046] Figure 5 Scanning electron microscope (SEM) images of graphene oxide and oxygen-rich / nitrogen-enriched organic molecule-functionalized graphene oxide composite materials before and after adsorption of 1-naphthol provided by this invention; wherein Figure 5 A is a SEM image of graphene oxide. Figure 5 B is a SEM image (scale bar 50 μm) of the oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material. Figure 5 C is a SEM image of the oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material after adsorption of 1-naphthol; Figure 6 This is a scanning electron microscope (SEM) image (scale bar 90 μm) of an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material provided by this invention. Figure 5 and Figure 6As shown, the synthesis of oxygen-enriched / nitrogen-enriched organic molecule functionalized graphene oxide composite material was successful. This composite material retains the sheet structure of graphene oxide, and due to the covalent coupling of D-galactosamine hydrochloride molecules on the surface of GO, this special effect makes the surface of the composite material significantly thicker and rougher than that of pure GO. After adsorption of 1-naphthol, its surface morphology did not show significant changes.

[0047] like Figure 7 and Figure 8 As shown, the elemental distribution and composition of the surface of the oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material were analyzed by EDS elemental mapping and energy level spectrum. The surface of the composite material showed that C, N and O elements were evenly distributed, with C, N and O accounting for 66.16 wt.%, 11.14 wt.% and 22.70 wt.% respectively. The presence of N element in the sample indicates that D-galactosamine hydrochloride molecules were successfully grafted onto GO.

[0048] Summarize: The oxygen-enriched / nitrogen-enriched organic molecule functionalized graphene oxide composite material prepared in this invention successfully grafts D-galactosamine hydrochloride molecules onto GO via an amidation reaction. This composite material exhibits a stable structure and demonstrates certain adsorption effects on various dyes and phenolic compounds, with excellent adsorption performance and selectivity for 1-naphthol. It can rapidly adsorb 1-naphthol solutions of different pH values ​​within 120 min, enabling the enrichment and separation of 1-naphthol in aqueous solutions. Furthermore, this composite material exhibits excellent reusability, still efficiently adsorbing 1-naphthol even after 10 repeated adsorption-desorption processes, providing a new, efficient, and economical solution for industrial wastewater treatment.

[0049] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A functionalized graphene oxide composite material with oxygen-rich / nitrogen-enriched organic molecules, characterized in that, It includes a substrate and oxygen- / nitrogen-rich organic molecules, which form a functionalized composite material through a grafting reaction.

2. The oxygen-rich / nitrogen-enriched organic molecular functionalized graphene oxide composite material according to claim 1, characterized in that, The substrate is graphene oxide (GO), and the oxygen-rich / nitrogen-rich organic molecule is D-galactosamine hydrochloride (DGA).

3. A method for preparing an oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material, used to prepare the oxygen-rich / nitrogen-enriched organic molecule functionalized graphene oxide composite material as described in any one of claims 1-2, characterized in that, Includes the following steps: S1: Graphene oxide is uniformly dispersed in anhydrous N,N-dimethylformamide to obtain a graphene oxide dispersion. S2: The graphene oxide dispersion obtained in step S1 is uniformly mixed with D-galactosamine hydrochloride to obtain a reactant. An amidation reaction is carried out under anhydrous catalytic conditions. The resulting product is repeatedly washed with ethanol and ultrapure water and then freeze-dried to obtain a composite material.

4. The preparation of an oxygen-rich / nitrogen-enriched organic molecular functionalized graphene oxide composite material according to claim 3, characterized in that, The graphene oxide is a dry powder solid, and the purity of the D-galactosamine hydrochloride is higher than 95%.

5. The preparation of an oxygen-rich / nitrogen-enriched organic molecular functionalized graphene oxide composite material according to claim 3, characterized in that, 0.8-1.2g of graphene oxide, 70-160mL of anhydrous N,N-dimethylformamide and 0.9-3g of D-galactosamine hydrochloride were ultrasonically dispersed and mixed evenly.

6. The preparation of an oxygen-rich / nitrogen-enriched organic molecular functionalized graphene oxide composite material according to claim 3, characterized in that, In step S2, the anhydrous catalyst conditions are achieved by using 0.9-2.5 g of O-(7-azabenzotriazol-1-yl)-N,N,N',N'-tetramethylurea hexafluorophosphate (HATU) in combination with 2.0-4.0 mL of N,N-diisopropylethylamine as a catalyst, and the catalyst and reactants are ultrasonically stirred until they are uniformly mixed.

7. The preparation of an oxygen-rich / nitrogen-enriched organic molecular functionalized graphene oxide composite material according to claim 3, characterized in that, In step S2, the anhydrous catalytic conditions are achieved by a moisture-proof reflux device, and the reaction is carried out by heating and reflux at 120℃~180℃ for 15~38h.

8. The preparation of an oxygen-rich / nitrogen-enriched organic molecular functionalized graphene oxide composite material according to claim 3, characterized in that, In step S2, the amidation reaction is carried out under continuous stirring. After the reaction is completed, the reaction system is allowed to cool naturally to room temperature. The product is separated by vacuum filtration. The filter cake is washed repeatedly with 80-180 mL of ethanol and ultrapure water, and the washing is repeated at least three times. The solids remaining on the filter membrane are collected.

9. The application of the oxygen-enriched / nitrogen-enriched organic molecule functionalized graphene oxide composite material according to claim 1 in the selective adsorption and separation of dyes and phenolic compounds in aqueous solution.

10. The application according to claim 9, characterized in that, The dyes include methylene blue (MB) and alizarin yellow (AYR), and the phenolic compounds include 1-naphthol (1-NP), p-nitrophenol (PNP), m-nitrophenol (MNP), tert-butylhydroquinone (TBHQ), and hydroquinone (HQ), with an adsorption concentration of 30~60 mg / L.

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