Nanocellulose-based MIL-100-Fe composite aerogel, and preparation method and application thereof

Abstract

The application provides a nanocellulose-based MIL-100-Fe composite aerogel as well as a preparation method and application thereof, and belongs to the technical field of MOF modification and water treatment. The composite aerogel takes MIL-100-Fe as a matrix, is prepared by using a green synthesis method, and is prepared by using nanocellulose in situ and ex situ, and has a hybrid super-octahedron unit crystal morphology and mechanical performance of a typical molecular sieve structure. The preparation method provided by the application is safe and simple, and is environment-friendly. The composite aerogel prepared by the method has a large specific surface area, is not easily affected by environmental pH, has a fast adsorption rate, has a high adsorption capacity for organic pollutants, can be recycled, can efficiently remove emerging pollutants in a water environment, and is a green, non-toxic and environment-friendly new adsorption material.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of MOF modification and water treatment, and in particular to preparation of a nanocellulose-based MIL-100-Fe composite aerogel and application of the nanocellulose-based MIL-100-Fe composite aerogel in a water environment. BACKGROUND

[0002] Pharmaceuticals and personal care products (PPCPs) represented by diclofenac (DCF) can cause related environmental risks. As emerging environmental pollutants, PPCPs have attracted widespread social attention due to their toxicity, bioaccumulation and high persistence in aquatic environments.

[0003] At present, the main methods for removing PPCPs are biological methods, advanced oxidation processes (AOPs) and adsorption methods. The adsorption method is widely used due to its high efficiency, economy, practicality and renewability.

[0004] MIL series metal organic framework materials (MOFs) are one of the most attractive adsorbents due to their relatively high porosity, good water stability and low toxicity, and are often used to remove PPCPs in wastewater, and the MIL-100-Fe powder has a rigid zero-dimensional crystal structure and is composed of mesoporous cages with sizes of 2.5 and 2.9 nm, and can pass through window sizes of about 0.55 and 0.86 nm, respectively, and PPCPs represented by DCF have a molecular size of about 0.8 nm, so it is very suitable to use MIL-100-Fe to adsorb them.

[0005] Traditional hydrothermal reaction method for preparing MOF powder needs strict high-temperature and high-pressure conditions, and the large amount of use of auxiliary reagents such as acids and organic solvents can easily cause environmental pollution problems, especially the use of hydrogen fluoride, which is extremely dangerous and not environmentally friendly, as a mineralizer to promote the growth of MOF crystals in the synthesis of MIL-100-Fe is indispensable, and the powder form brings difficulties to the recycling after treatment and easily causes secondary pollution.

[0006] In addition, in the actual adsorption process, it is often necessary to have macropores, mesopores and micropores with a suitable proportion to promote the enrichment and adsorption of pollutants on the surface of the adsorbent, and the MOF crystal often only has micropores and mesopores, and lacks macropores to promote the mass transfer process of pollutants. Therefore, it is very necessary to find a green and sustainable material to modify and prepare a three-dimensional shaped material to promote the removal of organic pollutants.

[0007] Aerogels are a special material with continuous three-dimensional porous network, large pore size and certain pore structure, which endows them with strong liquid transport capacity and molecular mass transfer capacity. Preparing MOFs powder into gel form is an improvement direction, however, due to the poor interface compatibility between MOFs and aerogel base material, on the one hand, MOFs are easy to fall off from the prepared composite aerogel, on the other hand, the aerogel base material is easy to coat the MOFs crystals, so that they lose good pore structure and active adsorption sites, so they often only have certain adsorption capacity for macromolecular organic matter. Therefore, the preparation method of MOF aerogel needs to be improved to obtain a microstructure suitable for adsorbing PPCPs.

[0008] On the other hand, most fossil-based or synthetic polymers used to make aerogels (such as phenolic resin, polyphenylalkane, polyurea, polyimide, polyamide and polyurethane, etc.) are non-renewable and non-biodegradable, which limits the development of sustainable and eco-friendly aerogels.

[0009] Nanocellulose derived from natural waste biomass is a green, non-toxic organic polymer nanomaterial, but the application of nanocellulose is currently limited. For example, CN113861600A provides a bio-based porous material and its preparation method and application, which grafts positively charged metal organic framework material on the surface of cellulose nanocrystals to reduce the overall charge of cellulose nanocrystals, thereby promoting the self-assembly of cellulose nanocrystals and reducing the agglomeration of cellulose nanocrystals. Essentially, the invention modifies the nanocellulose crystals by using a small amount of metal organic framework material to occupy the surface functional groups of the nanocellulose crystals.

[0010] In addition, from the preparation method, after the modification of the cellulose nanocrystals by using the metal organic framework material, the cellulose nanocrystals are added as a filler / modifier into a polyvinyl alcohol solution, and the final composite aerogel is essentially still based on the petroleum-based polymer polyvinyl alcohol, and a crosslinking agent such as glutaraldehyde, which is not environmentally friendly, needs to be added. Due to the "particle-polymer interface incompatibility" in traditional petroleum-based polymer composite aerogels and the inherent heterogeneity of the two phases, the interfacial affinity between the two phases is weak, so the mechanical properties of the composite aerogel are poor and the MOF loading rate is low.

[0011] For example, CN113477234A provides a preparation method of MOF-loaded aerogel for adsorbing VOCs, which uses grafted and modified nanocellulose as an intercalating agent to support the high aspect ratio of nanocellulose to prevent the stacking of graphene oxide and maintain the single-layer characteristics of graphene oxide, and to participate in the construction of graphene oxide-based composite aerogel. In this invention, the main function of nanocellulose is to disperse graphene oxide. SUMMARY

[0012] In view of the above problems existing in the prior art, the application provides a nanocellulose-based MIL-100-Fe composite aerogel as well as a preparation method and application thereof. The preparation method provided by the application is safe and simple, is environment-friendly, and the prepared composite aerogel has a large specific surface area, is not easily affected by the environment pH, has a fast adsorption rate, has a high adsorption capacity for organic pollutants and can be recycled, can efficiently remove emerging pollutants in a water environment, and is a green, non-toxic and environment-friendly new adsorption material.

[0013] The technical scheme of the application is as follows:

[0014] A nanocellulose-based MIL-100-Fe composite aerogel, wherein the composite aerogel takes MIL-100-Fe as a matrix, is prepared by using a green synthesis method, and is prepared by using nanocellulose in situ and ex situ, has a hybrid super-octahedral unit crystal morphology with a typical molecular sieve structure and mechanical properties.

[0015] The preparation method of the nanocellulose-based MIL-100-Fe composite aerogel comprises the following steps:

[0016] S1, preparing solution 1: dissolving trimesic acid in an aqueous solution containing sodium hydroxide;

[0017] S2, preparing solution 2: dispersing ferrous sulfate heptahydrate in an aqueous solution containing nanocellulose and continuously stirring uniformly;

[0018] S3, after the solution is completely clarified, slowly dropping solution 1 into solution 2 to prepare a MIL-100-Fe suspension, and freeze-drying the suspension to obtain nanocellulose-modified MIL-100-Fe powder;

[0019] S4, adding the MIL-100-Fe powder into the aqueous solution of nanocellulose, continuously stirring and freeze-drying to obtain the nanocellulose-based MIL-100-Fe composite aerogel.

[0020] Preferably, in the aqueous solution of step S1, the concentration of sodium hydroxide is 0.5-1 mol / L; and the concentration of the prepared trimesic acid solution is 40-50 mg / L.

[0021] Preferably, in step S2, the concentration of the aqueous solution of nanocellulose is 0.5-1 g / L; and the mass ratio of ferrous sulfate heptahydrate to nanocellulose is 6-11:1.

[0022] Preferably, at least 0.67 mol of trimesic acid is used for each 1 mol of ferrous sulfate heptahydrate.

[0023] Preferably, in step S3, the solution 1 is added dropwise into the solution 2 by using a peristaltic pump, and the specific method is as follows: the solution 1 is slowly added into the solution 2 by using a peristaltic pump at a speed of 2-10 rpm, and the suspension is prepared by stirring for 12-24 h; and the nanocellulose modified MIL-100-Fe powder is obtained by freeze-drying the suspension for 24-36 h.

[0024] Preferably, in step S4, the mass concentration of the nanocellulose aqueous solution is 0.1-0.5%; and the mass ratio of the MIL-100-Fe powder to the nanocellulose is 0.5-2:1.

[0025] Preferably, in step S4, the MIL-100-Fe powder prepared in step S3 is added into the nanocellulose aqueous solution, and the mixed solution is freeze-dried for 36-48 h after being uniformly stirred.

[0026] The application further provides an application of the nanocellulose based MIL-100-Fe composite aerogel, which is used for adsorbing pharmaceutical and personal care product PPCPs organic pollutants in a water environment.

[0027] Preferably, the organic pollutant is diclofenac.

[0028] In the above step S1, further, the process of preparing the solution 1 can be as follows: sodium hydroxide is dissolved in deionized water, and then a rotary stirrer is used for mixing until uniform; and then trimesic acid is gradually added, so that the trimesic acid is completely dissolved in the deionized water.

[0029] In step S2, further, for example, the ferrous sulfate heptahydrate is slowly added into the nanocellulose solution, and continuous stirring is performed at room temperature for 0.5 h, and the ratio of the two substances is controlled to be Fe / nanocellulose=2 / 1.

[0030] In step S3, further, the solution 1 is slowly added into the solution 2 by using a peristaltic pump at a speed of 10 rpm, and the suspension is prepared by stirring for 18 h; and the nanocellulose modified MIL-100-Fe powder is obtained by freeze-drying the suspension for 24 h.

[0031] In step S4, further, the MIL-100-Fe powder is added into the nanocellulose aqueous solution with a mass fraction of 0.25%, and continuous stirring is performed for 3-4 h; and the nanocellulose based MIL-100-Fe composite aerogel is obtained by freeze-drying after being uniformly mixed for 48 h.

[0032] The application has the beneficial technical effects that:

[0033] 1. The application first uses nanocellulose in-situ modification to prepare nanocellulose modified MIL-100-Fe powder under normal temperature and pressure without adding any organic solvent, and then through mixing with nanocellulose solution, freeze-drying to prepare nanocellulose-based MIL-100-Fe composite aerogel, and the nanocellulose-based MIL-100-Fe composite aerogel is used for adsorbing emerging pollutants in water environment.

[0034] 2. The application adopts a green synthesis method of normal temperature and pressure and water as a solvent to prepare MIL-100-Fe powder, but due to the lack of temperature and pressure gradient in the green synthesis method, the MOF crystal prepared mainly exists in the form of irregular block crystal. In order to overcome this technical difficulty, the application uses nanocellulose to provide abundant nucleation sites for the growth of MOF crystals, and reasonably controls the crystal particle size through steric hindrance effect, and prepares hybrid super-octahedral units with typical molecular sieve structure. In addition, it can also promote electron transfer to improve the formation rate of MOF crystals.

[0035] Compared with other biomass materials, nanocellulose has lower energy consumption in the extraction process, because before mechanical peeling, the original cellulose fibers are pretreated to weaken the adhesion in the matrix. In addition, the introduction of carboxyl groups on nanocellulose enables it to realize electrostatic complexation with metal ions, which can stabilize the three-dimensional network structure of TOCNFs. Compared with inorganic aerogels and polymer aerogels, nanocellulose-based aerogels not only have low density, large porosity and high specific surface area, but also make up for the defects of poor mechanical strength, high price and complex operation equipment, and in addition, they also have good biocompatibility and biodegradability, so they are very suitable for environmental field.

[0036] 3. Compared with CN113861600A, the application realizes the fixation and controllable uniform dispersion of metal organic framework material by utilizing the rich surface functional groups of nanocellulose to chelate metal organic framework material. In addition, the application slows down the liquid-liquid exchange process in the crystal growth process by using nanocellulose, thereby converting the reaction into a heterogeneous reaction through soft-soft interaction, and changing the electron cloud distribution of iron clusters through the unique charge characteristics of the surface of nanocellulose, inducing the directional growth of crystals to form hybrid super-octahedral units with typical molecular sieve structure, thereby greatly improving the removal efficiency of PPCPs. Essentially, the application utilizes the characteristics of nanocellulose to realize the synthesis of MIL-100-Fe with good crystal morphology under normal temperature and pressure.

[0037] 4、Compared with CN113477234A, the main function of nanocellulose in the application is in-situ nucleation and ex-situ crosslinking. On the one hand, it induces the directional growth of crystals in the nucleation process of MIL-100-Fe, thereby forming hybrid super-octahedral units with typical molecular sieve structure. On the other hand, it uses nanocellulose as a substrate to prepare composite aerogels by taking advantage of the good interfacial compatibility between nanocellulose and MIL-100-Fe, the high aspect ratio and the rich functional groups of nanocellulose.

[0038] 5、The composite aerogel is prepared by a two-step in-situ-ex-situ synthesis method. In the in-situ preparation process, nanocellulose is mainly used to prepare MIL-100-Fe powder with good crystal morphology. In the ex-situ preparation process, environmentally friendly nanocellulose is still used as a substrate to prepare composite aerogels. Nanocellulose, which is hydrophilic but not water-soluble, has good interfacial compatibility with hydrophilic MIL-100-Fe powder. Nanocellulose has both flexibility and rigidity, so it is a good substrate material for composite aerogels.

[0039] 6、The nanocellulose-based MIL-100-Fe composite aerogel prepared in the application promotes the nucleation and growth of the crystal on the basis of maintaining the original crystal structure of the MIL-100-Fe powder, and gives the crystal powder a layered pore structure, with high specific surface area and high porosity, providing more active sites for adsorption. The adsorption capacity of diclofenac is increased from 337.06mg / g to 376.58mg / g, and the adsorption conforms to the Langmuir model, and the reaction is spontaneous and endothermic. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 It is a scanning electron micrograph (SEM) of the nanocellulose-based MIL-100-Fe composite aerogel prepared in Example 1 of the application.

[0041] Figure 2 It is an X-ray diffraction pattern (XRD) of the nanocellulose-based MIL-100-Fe composite aerogel prepared in Example 1 of the application.

[0042] Figure 3 It is an adsorption-desorption curve and pore size distribution graph (BET) of the nanocellulose-based MIL-100-Fe composite aerogel prepared in Example 1 of the application.

[0043] Figure 4 It is a kinetic curve graph of the nanocellulose-based MIL-100-Fe composite aerogel prepared in Example 1 of the application for removing diclofenac. DETAILED DESCRIPTION

[0044] The application will be described in greater detail below with reference to the drawings and embodiments. Obviously, the described embodiments are only a part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the application.

[0045] Embodiment 1

[0046] S1, preparation of solution 1: 2.8 g of H3BTC was dissolved in 60.0 mL of ultrapure water containing 1.6 g of NaOH.

[0047] S2, preparation of solution 2: 5.56 g of FeSO4·7H2O was dissolved in 170 mL of ultrapure water containing 0.5320 g of nanocellulose.

[0048] S3, after the solution was completely clarified, solution 1 was slowly dripped into solution 2 at a rate of 10 rpm by a peristaltic pump and continuously stirred for 18 h to prepare a suspension, and the suspension was freeze-dried for 24 h to prepare MIL-100-Fe@NC powder.

[0049] S4, 0.25 g of MIL-100-Fe@NC powder was added to 100 g of nanocellulose aqueous solution with a mass fraction of 0.25%, continuously stirred for 3 h, and the mixed solution was freeze-dried for 48 h to prepare nanocellulose-based MIL-100-Fe composite aerogel.

[0050] The nanocellulose-based MIL-100-Fe composite aerogel prepared was subjected to morphology test, Figure 1 The micro-morphology of the nanocellulose modified MIL-100-Fe powder and the nanocellulose-based MIL-100-Fe composite aerogel in this embodiment 1 was shown, Figure 1 It can be seen from a that the MIL-100-Fe modified by nanocellulose has good regular octahedral crystal morphology, and the size is about 600 nm, which shows that nanocellulose can play a role in promoting nucleation and anchoring dispersion in the preparation process of MIL-100-Fe. It can be seen from b that the nanocellulose-based MIL-100-Fe composite aerogel prepared has a uniform porous structure, which shows that the combination of MIL-100-Fe and nanocellulose helps to promote the mutual crosslinking between nanocellulose. Figure 1

[0051] The X-ray diffraction pattern (XRD) of the nanocellulose-based MIL-100-Fe composite aerogel in this embodiment 1 is as shown in Figure 2 ​The spectrum shows the characteristic peaks of its main component MIL-100-Fe, such as Fe 428 (2q = 10.6°), 4814 (2q = 19.7°) and 440 (2q = 31.9°) crystal faces. In addition, the characteristic peak corresponding to the type I structure of nanocellulose (2q = 22.1°) also appears in the XRD spectrum of the composite aerogel. It is shown that the nanocellulose-based MIL-100-Fe composite aerogel retains the original crystal structure of nanocellulose and MIL-100-Fe, and the composite material has good crystallinity.

[0052] Example 2:

[0053] S1, Preparation of solution 1: 2.4 g of H3BTC was dissolved in 60.0 mL of ultrapure water containing 0.8 g of NaOH.

[0054] S2, Preparation of solution 2: 5.56 g of FeSO4·7H2O was dissolved in 170 mL of ultrapure water containing 0.5054 g of nanocellulose.

[0055] S3, After the solution was completely clarified, solution 1 was slowly dropped into solution 2 at a rate of 10 rpm by peristaltic pump and continuously stirred for 12 h to prepare a suspension, and the suspension was freeze-dried for 24 h to prepare MIL-100-Fe@NC powder.

[0056] S4, 0.125 g of MIL-100-Fe@NC powder was added to 100 g of nanocellulose aqueous solution with a mass fraction of 0.25%, and continuously stirred for 3 h, and the mixed solution was freeze-dried for 36 h to prepare nanocellulose-based MIL-100-Fe composite aerogel.

[0057] The nanocellulose-based MIL-100-Fe composite aerogel prepared in this example has a MIL-100-Fe loading of 33.33%, and the MIL-100-Fe in the composite aerogel still has a good octahedral crystal morphology and a uniform porous structure.

[0058] Example 3:

[0059] S1, Preparation of solution 1: 3.0 g of H3BTC was dissolved in 60.0 mL of ultrapure water containing 1.6 g of NaOH.

[0060] S2, Preparation of solution 2: 5.56 g of FeSO4·7H2O was dissolved in 170 mL of ultrapure water containing 0.9267 g of nanocellulose.

[0061] S3, after the solution is completely clear, the solution 1 is slowly dropped into the solution 2 at a rate of 10 rpm by a peristaltic pump and continuously stirred for 24 h to prepare a suspension, and the suspension is freeze-dried for 36 h to prepare the MIL-100-Fe@NC powder.

[0062] S4, 0.5 g of the MIL-100-Fe@NC powder is added into 100 g of the nanocellulose aqueous solution with a mass fraction of 0.25% and continuously stirred for 3 h, and the mixed solution is freeze-dried for 48 h to prepare the nanocellulose-based MIL-100-Fe composite aerogel.

[0063] The nanocellulose-based MIL-100-Fe composite aerogel prepared in the embodiment has a MIL-100-Fe loading of 66.67%, and the composite aerogel retains the original crystal structures of the nanocellulose and the MIL-100-Fe, and the composite material has good crystallinity.

[0064] Test Example 1

[0065] The sample prepared in Example 1 is subjected to nitrogen adsorption-desorption test under the condition of 77 k liquid nitrogen by using a 4-station full-automatic specific surface area analyzer of the model of Micromeritics APS P2460, and the result is shown in Table 1. Figure 3 The adsorption-desorption curve and the pore size distribution diagram of the nanocellulose-based MIL-100-Fe composite aerogel in the embodiment 1 are shown in Table 1, and the triangular and circular curves in the table represent the nitrogen adsorption and desorption of the sample, respectively. As can be seen from the table, the N2 adsorption-desorption curve presents type IV adsorption behavior H3 hysteresis curve, indicating that there is a uniform mesoporous and microporous structure in the material, thereby improving the adsorption performance of the composite material.

[0066] Application Example 2

[0067] The adsorption experiment is carried out in a 200 mL flask, 0.05 g of the nanocellulose-based MIL-100-Fe composite aerogel is added into a diclofenac solution with a concentration of 100 mg / L, and the composite aerogel is fully mixed with the diclofenac solution at room temperature (25℃) by using an air bath shaker at a speed of 200 r / min. After reaching the adsorption equilibrium, the separation is carried out by using a filter membrane (with a pore size of 0.22 μm). Finally, the concentration of the diclofenac is measured by using a UV spectrophotometer at a wavelength of 276 nm.

[0068] The comparative material is a MIL-100-Fe powder obtained by a traditional green synthesis method and a nanocellulose-based MIL-100-Fe powder, and the preparation method is as shown below.

[0069] (1) MIL-100-Fe powder

[0070] M1, Preparation of solution 1: 2.8 g of H3BTC was dissolved in 60.0 mL of ultrapure water containing 1.6 g of NaOH.

[0071] M2, Preparation of solution 2: 5.56 g of FeS04-7H20 was dissolved in 170 mL of ultrapure water.

[0072] M3, After the solution was completely clarified, solution 1 was slowly dripped into solution 2 at a rate of 10 rpm by peristaltic pump and continuously stirred for 18 h to prepare a suspension, and the suspension was freeze-dried for 24 h to prepare a nanocellulose-based MIL-100-Fe powder.

[0073] (2) Nanocellulose-based MIL-100-Fe powder

[0074] N1, Preparation of solution 1: 2.8 g of H3BTC was dissolved in 60.0 mL of ultrapure water containing 1.6 g of NaOH.

[0075] N2, Preparation of solution 2: 5.56 g of FeS04-7H20 was dissolved in 170 mL of ultrapure water containing 0.5320 g of nanocellulose.

[0076] N3, After the solution was completely clarified, solution 1 was slowly dripped into solution 2 at a rate of 10 rpm by peristaltic pump and continuously stirred for 18 h to prepare a suspension, and the suspension was freeze-dried for 24 h to prepare a nanocellulose-based MIL-100-Fe powder.

[0077] The experimental results are shown in Table 1. Figure 4 As shown in Table 1, compared with the MIL-100-Fe powder prepared by the conventional green synthesis method, the removal rate of nanocellulose-based MIL-100-Fe for diclofenac was increased from 75.49% to 84.26%, the maximum adsorption capacity was increased from 301.97 mg / g to 337.06 mg / g, and after the nanocellulose-based MIL-100-Fe was prepared into an aerogel, the removal rate was further increased to 94.15%, and the maximum adsorption capacity was also increased to 376.58 mg / g.

[0078] Although the embodiments of the present application have been disclosed as above, they are not limited only to the applications listed in the specification and the embodiments, and can be fully applied to various fields suitable for the present application. Those skilled in the art can make various changes, modifications, replacements, and variations to the embodiments without departing from the principles and spirits of the present application, and the present application is not limited to specific details without departing from the general concept defined by the claims and the equivalent scope.

Claims

1. A method for preparing a nanocellulose-based MIL-100-Fe composite aerogel, characterized in that, The composite aerogel takes MIL-100-Fe as a matrix, is prepared by using a green synthesis method and nanocellulose in situ and ex situ, has a typical molecular sieve structure of hybrid super-octahedral unit crystal morphology and mechanical performance, and the carboxyl introduced on the nanocellulose enables the nanocellulose to realize electrostatic complexation with metal ions, thereby stabilizing the three-dimensional network structure of the TOCNFs. The preparation method comprises the following steps: S1, preparing solution 1: dissolving trimesic acid in an aqueous solution containing sodium hydroxide; S2, preparing solution 2: dispersing ferrous sulfate heptahydrate in an aqueous solution containing nanocellulose and continuously stirring to be uniform; S3, after the solution is completely clarified, slowly dropping solution 1 into solution 2 to prepare a MIL-100-Fe suspension, and freeze-drying the suspension to obtain nanocellulose modified MIL-100-Fe powder; S4, adding the MIL-100-Fe powder into an aqueous solution of nanocellulose, continuously stirring, and freeze-drying to obtain nanocellulose based MIL-100-Fe composite aerogel; In the aqueous solution of step S1, the concentration of sodium hydroxide is 0.5-1 mol / L; and the concentration of the prepared trimesic acid solution is 40-50 mg / L; In step S2, the concentration of the aqueous solution of nanocellulose ranges from 0.5 to 1 g / L; and the mass ratio of ferrous sulfate heptahydrate to nanocellulose is 6-11:1; At least 0.67 mol of trimesic acid is used per 1 mol of ferrous sulfate heptahydrate; In step S4, the mass concentration of the aqueous solution of nanocellulose is 0.1-0.5%, and the mass ratio of MIL-100-Fe powder to nanocellulose is 0.5-2:

1.

2. The production method according to claim 1, characterized by, In step S3, the solution 1 is added to solution 2 by a peristaltic pump, and the specific method is as follows: the solution 1 is slowly added to solution 2 at a speed of 2-10 rpm by a peristaltic pump, stirring for 12-24 h to prepare a suspension, and freeze-drying the suspension for 24-36 h to obtain nanocellulose modified MIL-100-Fe powder.

3. The preparation method according to claim 1, characterized in that, In step S4, the MIL-100-Fe powder prepared in step S3 is added to an aqueous solution of nanocellulose, the mixture is stirred uniformly, and then the mixture is freeze-dried for 36-48 h.

4. Use of the nanocellulose-based MIL-100-Fe composite aerogel according to any one of claims 1 to 3, characterized in that The composite aerogel is used for adsorbing pharmaceutical and personal care product (PPCP) organic pollutants in a water environment, and the organic pollutants are diclofenac.

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