阅读说明：本技术 一种纤维素生物质基原位介孔复合材料的制备方法及应用 (Preparation method and application of cellulose biomass-based in-situ mesoporous composite material ) 是由 陶金 刘雷艮 张技术 吴建兵 王薇 孙银银 于 2021-07-26 设计创作，主要内容包括：本发明公开了一种纤维素生物质基原位介孔复合材料的制备方法,包括步骤：将纤维素生物质浸入碱溶液处理,采用“共缩聚-诱导原位生成”策略在生物质材料基体上制备出功能化介孔氧化硅复合材料,并采用端羟基超支化聚合物对复合材料进行功能增强修饰。本发明提供的介孔复合材料制备条件温和,工艺简单,周期较短,成本低廉,易于实现规模化工业生产,具有广阔应用前景；产品表面介孔材料分散密度高,物理化学结构稳定,吸附性能强,机械回收性好,可应用于重金属和有机废水吸附处理及重金属回收等领域。(The invention discloses a preparation method of a cellulose biomass-based in-situ mesoporous composite material, which comprises the following steps: immersing cellulose biomass into an alkali solution for treatment, preparing a functionalized mesoporous silicon oxide composite material on a biomass material substrate by adopting a copolycondensation-induction in-situ generation strategy, and performing function enhancement modification on the composite material by adopting a hydroxyl-terminated hyperbranched polymer. The mesoporous composite material provided by the invention has the advantages of mild preparation conditions, simple process, short period, low cost, easiness in realization of large-scale industrial production and wide application prospect; the mesoporous material on the surface of the product has high dispersion density, stable physical and chemical structure, strong adsorption performance and good mechanical recoverability, and can be applied to the fields of heavy metal and organic wastewater adsorption treatment, heavy metal recovery and the like.)

1. A preparation method of a cellulose biomass-based in-situ mesoporous composite material is characterized by comprising the following steps:

s1, soaking the cellulose biomass material in an alkali solution with the concentration of 1-30 wt% for heating treatment, then filtering and fully washing a product, and drying to constant weight to obtain an activated biomass material;

s2, dissolving a template agent, an organic solvent and an alkaline regulator in water, heating to 30-100 ℃, mixing and stirring for 10-120 min, and controlling the molar ratio of the template agent to the alkaline regulator to the organic solvent to the water to be 0.05-5: 0.5-60: 100;

s3, adding a functional silane coupling agent and orthosilicate ester into the mixed system of the step S2, continuously stirring for 10-120 min at 30-100 ℃, controlling the molar ratio of the orthosilicate ester to the functional silane coupling agent to be 0.01-5: 1, and controlling the mass volume ratio of the orthosilicate ester to the mixed system of the step S2 to be 2-10%;

s4, adding the activated biomass material into the mixed system obtained in the S3 at a bath ratio of 1: 20-200, and standing for 6-48 h at 30-100 ℃;

s5, filtering the biomass material from the mixed system, taking out, washing, drying, placing under protective gas at 40-120 ℃, refluxing for 2-24 h by adopting an organic solvent, filtering, washing, and drying in vacuum to obtain a primary biomass-based mesoporous composite material;

s6, dispersing the primary biomass-based mesoporous composite material in 1-20 wt% of organic solvent solution of hydroxyl-terminated hyperbranched polymer, stirring and reacting at 30-100 ℃ for 0.5-6 h at a bath ratio of 1: 20-200, filtering and taking out the material, washing, and drying in vacuum to obtain the cellulose biomass-based in-situ mesoporous composite material.

2. The method for preparing the cellulose biomass-based in-situ mesoporous composite material according to claim 1, wherein in the step S1, the cellulose biomass material is sequentially immersed in 2 to 5 alkali solutions with the concentration of 1 to 30 wt% according to the concentration increasing sequence for heating treatment, and the concentration difference of the alkali solutions in two adjacent treatments is more than 5 wt%.

3. The method of claim 1, wherein the cellulosic biomass is cotton, hemp, wheat straw, rice straw, or bagasse.

4. The method of claim 1, wherein the alkali solution is one or more of a sodium hydroxide solution, a sodium carbonate solution, or a sodium bicarbonate solution.

5. The method of claim 1, wherein the template agent is one or more of cetyltrimethylammonium chloride or cetyltrimethylammonium bromide.

6. The method of claim 1, wherein the alkalinity regulator is one or more of ethanolamine, diethanolamine, triethanolamine, and ammonia.

7. The method for preparing the cellulose biomass-based in-situ mesoporous composite material according to claim 1, wherein the functional silane coupling agent is one or more of 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropylmethyldiethoxysilane and 3-aminopropyltriethoxysilane.

8. The method of claim 1, wherein the orthosilicate is one or more of methyl orthosilicate, ethyl orthosilicate, propyl orthosilicate, and butyl orthosilicate.

9. The method of claim 1, wherein the organic solvent is one or more of methanol, absolute ethanol, acetone, toluene, cyclohexane, and isopropanol.

10. The application of the cellulose biomass-based in-situ mesoporous composite material is characterized in that the cellulose biomass-based in-situ mesoporous composite material prepared by any one of claims 1 to 9 is used for adsorbing organic pollutants and/or heavy metal ions polluting water bodies.

Technical Field

The invention relates to a preparation method and application of a mesoporous composite material, in particular to a preparation method and application of a cellulose biomass-based in-situ mesoporous composite material.

Background

The mesoporous silicon is a silicon-based porous material with the aperture between 2 nm and 50nm, has the advantages of large specific surface area, good hydrothermal stability, high plasticity, strong modifiability and the like, and has great application potential in the fields of adsorption, catalysis, sensing, separation and the like. On the basis, the micro-nano mesoporous silicon spheres have high surface energy, high mass transfer rate, high-density functional sites and obvious interface effect, and have high-efficiency adsorption performance on organic wastewater and heavy metals. However, the mesoporous silicon is separately adopted to adsorb heavy metal wastewater, and the mesoporous silicon is not easy to recover after being dispersed in water, which may cause secondary pollution and affect the adsorption effect.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide a preparation method of a cellulose biomass-based in-situ mesoporous composite material, and aims to solve the problem of recycling the mesoporous silicon composite material so that the mesoporous silicon composite material can be recycled. The invention also aims to provide the application of the cellulose biomass-based in-situ mesoporous composite material.

The technical scheme of the invention is as follows: a preparation method of a cellulose biomass-based in-situ mesoporous composite material comprises the following steps:

s1, soaking the cellulose biomass material in an alkali solution with the concentration of 1-30 wt% for heating treatment, filtering and fully washing a product, and drying to constant weight to obtain an activated biomass material;

s2, dissolving a template agent, an organic solvent and an alkaline regulator in water, heating to 30-100 ℃, mixing and stirring for 10-120 min, and controlling the molar ratio of the template agent to the alkaline regulator to the organic solvent to the water to be 0.05-5: 0.5-60: 100;

s3, adding a functional silane coupling agent and orthosilicate into the mixed system of the step S2, continuously stirring for 10-120 min at 30-100 ℃, controlling the molar ratio of the components to the functional silane coupling agent to the orthosilicate to be 0.01-5: 1, wherein the mass volume ratio of the orthosilicate to the mixed system of the step S2 is 2-10%;

s4, adding the activated biomass material into the mixed system obtained in the S3 at a bath ratio of 1: 20-200, and standing for 6-48 h at 30-100 ℃;

s5, filtering the biomass material from the mixed system, taking out, washing, drying, placing under protective gas at 40-120 ℃, refluxing for 2-24 h by adopting an organic solvent, filtering, washing, and drying in vacuum to obtain a primary biomass-based mesoporous composite material;

s6, dispersing the primary biomass-based mesoporous composite material in 1-20 wt% of organic solvent solution of hydroxyl-terminated hyperbranched polymer, stirring and reacting at 30-100 ℃ for 0.5-6 h at a bath ratio of 1: 20-200, filtering and taking out the material, washing, and drying in vacuum to obtain the cellulose biomass-based in-situ mesoporous composite material.

Further, in the step S1, the cellulosic biomass material is sequentially immersed in 2 to 5 alkali solutions with a concentration of 1 to 30 wt% according to the concentration increasing order for heating treatment, and the concentration difference between the alkali solutions treated in two adjacent times is greater than 5 wt%.

Further, the cellulose biomass is cotton, hemp, wheat straw, rice straw or bagasse.

Further, the alkali solution is one or more of a sodium hydroxide solution, a sodium carbonate solution or a sodium bicarbonate solution.

Further, the template agent is one or more of cetyltrimethylammonium chloride or cetyltrimethylammonium bromide.

Further, the alkalinity regulator is one or more of ethanolamine, diethanolamine, triethanolamine and ammonia water.

Further, the functional silane coupling agent is one or more of 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropylmethyldiethoxysilane and 3-aminopropyltriethoxysilane.

Further, the orthosilicate is one or more of methyl orthosilicate, ethyl orthosilicate, propyl orthosilicate and butyl orthosilicate.

Further, the organic solvent is one or more of methanol, absolute ethyl alcohol, acetone, toluene, cyclohexane and isopropanol.

The application of the cellulose biomass-based in-situ mesoporous composite material is used for adsorbing organic pollutants and/or heavy metal ions polluting water bodies.

The preparation method of the hydroxyl-terminated hyperbranched polymer is disclosed in Xu S, Chen S, Zhang F, et al.preparation and controlled coating of hydroxyl-modified silver nanoparticles through interaction-induced selected-assembly [ J ] Materials & Design,2016: 107-assembly 118, which is obtained by the synthetic reaction of one of monomers containing double bonds and carboxyl or lipid groups with polyhydroxy monomers and organic acids. The monomer containing double bonds and carboxyl or aliphatic groups is methyl acrylate, ethyl acrylate, methyl methacrylate, acrylic acid or methacrylic acid; the polyhydroxy monomer is iminodiethanol, trimethylolethane or trimethylolpropane; the organic acid is dodecyl benzene sulfonic acid, m-toluenesulfonic acid, o-toluenesulfonic acid or p-toluenesulfonic acid.

Compared with the prior art, the invention has the advantages that:

by adopting a copolycondensation-induction in-situ generation strategy and utilizing cellulose biomass with negative electricity to induce a silicon source to directly condense on the surface of the silicon source to generate amino-functionalized mesoporous silicon, the biomass-based mesoporous composite material with high dispersion density is obtained, the efficient adsorption performance of the functional mesoporous silicon can be fully exerted, and the recyclability of the biomass carrier can be utilized. The biomass material is activated by adopting the multi-concentration alkali solution in sequence, so that hydrogen bonds in the macromolecular chains can be further opened, the fiber bundles are fully swelled, the effective reaction space of the biomass is improved, and the reaction activity is enhanced.

A hydroxyl-terminated hyperbranched polymer is introduced into the high specific surface structure of the in-situ mesoporous silicon, the hydroxyl-terminated hyperbranched polymer has a spheroidal network branched molecular structure, high rheological property, low viscosity and more active reaction sites, and is favorable for fully expanding when the nano porous material is modified and difficult to block a nano pore channel; the cavity structure containing a large number of active sites can effectively control the nano material, form electrostatic repulsion among particles and prevent agglomeration; the hyperbranched polymer can induce the nano material to be assembled on the surface of the nano material through electrostatic effect, strong hydrogen bond acting force is easily formed between the high-density terminal active functional group of the hyperbranched polymer and the nano material, the stable structure is favorably constructed, and in addition, the functional group rich in the hyperbranched polymer can capture pollutant particles to participate in synergistic adsorption.

The mesoporous composite material has the advantages of mild preparation conditions, simple process, short period, rich sources of used biomass materials and mesoporous silicon materials, low cost, strong plasticity, easy realization of large-scale industrial production and wide application prospect; the mesoporous material on the surface of the product has high dispersion density, stable physical and chemical structure, strong adsorption performance and good mechanical recoverability, and can be applied to the fields of heavy metal and organic wastewater adsorption treatment, heavy metal recovery and the like.

Drawings

Fig. 1 is a molecular structural formula of a hyperbranched polymer adopted by the cellulose biomass-based in-situ mesoporous composite material prepared by the embodiment of the invention.

Fig. 2 is a scanning electron microscope image of the cellulose biomass-based in-situ mesoporous composite material prepared in example 2 of the present invention.

Fig. 3 is a static adsorption kinetics curve diagram of the cellulose biomass-based in-situ mesoporous composite material prepared in embodiment 2 of the present invention for adsorbing organic dye and heavy metal ions.

Fig. 4 is a line graph showing the regeneration adsorption performance of the cellulose biomass-based in-situ mesoporous composite material prepared in example 2 of the present invention on organic dyes and heavy metal ions.

Detailed Description

The present invention is further illustrated by the following examples, which are not to be construed as limiting the invention thereto.

Example 1:

the cotton fiber was immersed in a 5 wt% sodium hydroxide solution for heat treatment (100 ℃), and then the product was filtered and washed thoroughly, dried to constant weight, to obtain an activated cotton fiber.

Dissolving cetyl trimethyl ammonium chloride, anhydrous ethanol and diethanolamine in water, heating to 50 deg.C, mixing and stirring for 30 min. The molar ratio of hexadecyl trimethyl ammonium chloride to diethanolamine to absolute ethyl alcohol to water is controlled to be 0.3: 1: 5: 100.

Adding 3-aminopropyltrimethoxysilane and ethyl orthosilicate into the mixed system, continuously stirring for 60min at 50 ℃, and controlling the molar ratio of the components to be 3-aminopropyltrimethoxysilane: the ratio of ethyl orthosilicate to mixed system is 0.5: 1, and the mass volume ratio of ethyl orthosilicate to mixed system is 8.4%.

Adding 5g of activated cotton fiber into the mixed system at a bath ratio of 1: 100, and standing at 50 deg.C for 12 hr.

And filtering and taking out the cotton fibers from the mixed system, washing, drying, placing under nitrogen at 60 ℃, refluxing for 6 hours by using absolute ethyl alcohol, filtering, washing and drying in vacuum to obtain the primary biomass-based mesoporous composite material.

Dispersing 5g of the primary composite material in 5 wt% of organic solvent solution of hydroxyl-terminated hyperbranched polymer at a bath ratio of 1: 100, stirring and reacting for 2h at 60 ℃, filtering and taking out the material, washing, and drying in vacuum to obtain the cellulose biomass-based in-situ mesoporous composite material. The molecular structure of the hydroxyl-terminated hyperbranched polymer is shown in figure 1, and the hydroxyl-terminated hyperbranched polymer has a highly branched cavity structure and rich active groups such as carbonyl, hydroxyl and the like, and can remarkably enhance the functional activity of the composite material.

Adding organic dye (methylene blue) with certain concentration and pH value and heavy metal ions (Cu) into the prepared cellulose biomass-based in-situ mesoporous composite material²⁺) The simulated wastewater of (1) was subjected to an oscillation adsorption experiment and an adsorption-desorption cyclic utilization experiment, and the results were as follows:

after 4 times of adsorption-desorption cyclic utilization processes, the average adsorption capacity of the two pollutants can still be kept to be more than 73% of the first saturated adsorption capacity. Test results show that the composite material adopts a copolycondensation-induction in-situ generation strategy to introduce mesoporous silicon, has strong surface adsorption structure stability and good regeneration adsorption performance, and can be used as a biomass adsorption material with strong sustainability.

Example 2:

soaking cotton fiber in 2 wt% concentration sodium hydroxide solution for heating treatment (100 deg.c), filtering the product, soaking in 10 wt% concentration sodium hydroxide solution for heating treatment (50 deg.c), filtering the product, washing and stoving to constant weight to obtain the activated cotton fiber.

Dissolving cetyl trimethyl ammonium chloride, anhydrous ethanol and diethanolamine in water, heating to 50 deg.C, mixing and stirring for 30 min. The molar ratio of hexadecyl trimethyl ammonium chloride to diethanolamine to absolute ethyl alcohol to water is controlled to be 0.3: 1: 5: 100.

Adding 3-aminopropyltrimethoxysilane and ethyl orthosilicate into the mixed system, continuously stirring for 60min at 50 ℃, and controlling the molar ratio of the components to be 3-aminopropyltrimethoxysilane: the ratio of ethyl orthosilicate is 0.6: 1. The mass volume ratio of the ethyl orthosilicate to the mixed system is 6.4%.

Adding 5g of activated cotton fiber into the mixed system at a bath ratio of 1: 100, and standing at 50 deg.C for 12 hr.

And filtering and taking out the cotton fibers from the mixed system, washing, drying, placing under nitrogen at 60 ℃, refluxing for 6 hours by using absolute ethyl alcohol, filtering, washing and drying in vacuum to obtain the primary biomass-based mesoporous composite material.

Dispersing 5g of the primary composite material in 5 wt% of organic solvent solution of hydroxyl-terminated hyperbranched polymer at a bath ratio of 1: 100, stirring and reacting for 2h at 60 ℃, filtering and taking out the material, washing, and drying in vacuum to obtain the cellulose biomass-based in-situ mesoporous composite material. FIG. 2 is a scanning electron micrograph of the composite materialA large amount of mesoporous silicon microspheres with the particle size of about 100-1000 nm are generated on the surface of a substance in situ, and the surface of the substance is covered with hyperbranched polymers, so that the specific surface area and the functionality of the material are obviously improved. FIG. 3 shows the adsorption of organic dye (methylene blue) and heavy metal ion (Cu) by the composite material²⁺) The experiment result proves that the mesoporous silicon-hyperbranched adsorption structure of the composite material has high-efficiency adsorption performance on two pollutants, and the saturated adsorption capacity is 222mg/g and 124mg/g respectively. FIG. 4 is a line graph showing the regeneration adsorption performance of the composite material on organic dyes and heavy metal ions. After four times of adsorption-desorption cyclic utilization processes, the average adsorption capacity of the two pollutants can still be kept to be more than 80% of the first saturated adsorption capacity.

Experimental results prove that alkali solution with gradually increased concentration is adopted to carry out multiple activation treatment, hydrogen bonds in macromolecular chains can be further opened, the surfaces of the biomasses are fully swelled, the effective reaction space of the biomasses is improved, the reaction activity is enhanced, and therefore the static saturated adsorption capacity and the cyclic adsorption capacity of the composite material to pollutants are effectively improved.

Example 3:

the fibrilia is firstly soaked in a sodium carbonate solution with the concentration of 5 wt% for heating treatment (120 ℃), the product is filtered and then soaked in the sodium carbonate solution with the concentration of 10 wt% for heating treatment (40 ℃), the product is filtered and then soaked in the sodium carbonate solution with the concentration of 25 wt% (40 ℃) for heating treatment, and then the product is filtered and fully washed, and is dried to constant weight, so that the activated fibrilia is obtained.

Dissolving cetyl trimethyl ammonium bromide, methanol and triethanolamine in water, heating to 50 deg.C, mixing and stirring for 30 min. The molar ratio of hexadecyl trimethyl ammonium bromide to triethanolamine to methanol to water is controlled to be 0.5: 2: 7: 100.

Adding 3-aminopropyltriethoxysilane and methyl orthosilicate into the mixed system, continuously stirring for 120min at 60 ℃, and controlling the molar ratio of the components 3-aminopropyltriethoxysilane: the ratio of methyl orthosilicate to methyl orthosilicate is 0.3: 1, and the mass volume ratio of methyl orthosilicate to a mixed system is 5.2%.

Adding 10g of activated fibrilia into the above mixed system at bath ratio of 1: 80, and standing at 80 deg.C for 24 hr.

And filtering and taking out the fibrilia from the mixed system, washing, drying, refluxing for 8 hours by adopting methanol at the temperature of 60 ℃ under nitrogen, filtering, washing and drying in vacuum to obtain the primary biomass-based mesoporous composite material.

Dispersing 10g of the primary composite material in 25 wt% of organic solvent solution of hydroxyl-terminated hyperbranched polymer at a bath ratio of 1: 80, stirring and reacting for 5h at 60 ℃, filtering and taking out the material, washing, and drying in vacuum to obtain the cellulose biomass-based in-situ mesoporous composite material. The material is subjected to organic dye (methylene blue) and heavy metal ion (Cu)²⁺) In static adsorption experiment, the saturated adsorption capacity of methylene blue is 205mg/g, and Cu is²⁺The saturated adsorption amount of (2) is 116mg/g, the adsorption-desorption cycle is carried out for 4 times, the average adsorption amount of methylene blue is 166mg/g, and Cu is²⁺The average adsorbed amount of (3) was 99 mg/g.

Example 4:

the straw fibers were first immersed in a 5 wt% sodium bicarbonate solution for heat treatment (100 ℃ C.), the product was filtered and then immersed in a 20 wt% sodium bicarbonate solution for heat treatment (50 ℃ C.), and then the product was filtered and washed thoroughly, dried to constant weight, to obtain activated straw fibers.

Dissolving cetyl trimethyl ammonium bromide, anhydrous ethanol and triethanolamine in water, heating to 60 deg.C, mixing and stirring for 60 min. The molar ratio of hexadecyl trimethyl ammonium bromide to triethanolamine to absolute ethyl alcohol to water is controlled to be 0.5: 3: 5: 100.

Adding 3-aminopropyltriethoxysilane and ethyl orthosilicate into the mixed system, continuously stirring for 60min at 50 ℃, and controlling the molar ratio of the components 3-aminopropyltriethoxysilane: the ratio of ethyl orthosilicate to mixed system is 0.4: 1, and the mass volume ratio of ethyl orthosilicate to mixed system is 6.8%.

Adding 5g of activated straw fiber into the above mixed system at bath ratio of 1: 100, and standing at 50 deg.C for 12 hr.

And filtering and taking out the straw fiber from the mixed system, washing, drying, refluxing for 6 hours by adopting absolute ethyl alcohol at the temperature of 60 ℃ under nitrogen, filtering, washing and drying in vacuum to obtain the primary biomass-based mesoporous composite material.

Dispersing 5g of the primary composite material in 5 wt% of organic solvent solution of hydroxyl-terminated hyperbranched polymer at a bath ratio of 1: 100, stirring and reacting for 2h at 60 ℃, filtering and taking out the material, washing, and drying in vacuum to obtain the cellulose biomass-based in-situ mesoporous composite material. The material is subjected to organic dye (methylene blue) and heavy metal ion (Cu)²⁺) In static adsorption experiment, the saturated adsorption capacity of methylene blue is 217mg/g, and Cu is²⁺The saturated adsorption amount of (2) is 109mg/g, the adsorption-desorption cycle is carried out for 4 times, the average adsorption amount of methylene blue is 153mg/g, and Cu is²⁺The average adsorbed amount of (2) was 85 mg/g.

Example 5:

the method comprises the steps of firstly soaking wheat straw fibers in a 5 wt% sodium carbonate solution for heating treatment (120 ℃), filtering a product, then soaking the filtered product in a 10 wt% sodium carbonate solution for heating treatment (60 ℃), then filtering the product, then soaking the filtered product in a 20 wt% sodium carbonate solution for heating treatment (40 ℃), finally filtering the product, then soaking the filtered product in a 25 wt% sodium carbonate solution for heating treatment (30 ℃), then filtering and fully washing the product, and drying to constant weight to obtain the activated wheat straw fibers.

Dissolving hexadecyl trimethyl ammonium chloride, absolute ethyl alcohol and ethanolamine in water, heating to 65 ℃, mixing and stirring for 90 min. The molar ratio of hexadecyl trimethyl ammonium chloride to ethanolamine to absolute ethyl alcohol to water is controlled to be 0.3: 3: 6: 100.

Adding 3-aminopropyltrimethoxysilane and methyl orthosilicate into the mixed system, continuously stirring for 90min at 65 ℃, and controlling the molar ratio of the components to be 3-aminopropyltrimethoxysilane: the ratio of methyl orthosilicate to methyl orthosilicate is 0.25: 1, and the mass volume ratio of methyl orthosilicate to a mixed system is 5.6%.

Adding 10g of activated wheat straw fiber into the mixed system at a bath ratio of 1: 50, and standing at 65 deg.C for 9 h.

And filtering and taking out the wheat straw fiber from the mixed system, washing, drying, placing under nitrogen at 60 ℃, refluxing for 6 hours by using absolute ethyl alcohol, filtering, washing and drying in vacuum to obtain the primary biomass-based mesoporous composite material.

Dispersing 10g of the primary composite material in 10 wt% of organic solvent solution of hydroxyl-terminated hyperbranched polymer at a bath ratio of 1: 50, stirring and reacting for 4h at 65 ℃, filtering and taking out the material, washing, and drying in vacuum to obtain the cellulose biomass-based in-situ mesoporous composite material. The material is subjected to organic dye (methylene blue) and heavy metal ion (Cu)²⁺) In static adsorption experiment, the saturated adsorption capacity of methylene blue is 219mg/g, and Cu is²⁺The saturated adsorption amount of (2) was 118mg/g, the adsorption-desorption cycle was performed for 4 times, the average adsorption amount of methylene blue was 179mg/g, Cu was²⁺The average adsorbed amount of (2) was 90 mg/g.

Example 6:

the fibrilia is firstly soaked in a sodium hydroxide solution with the concentration of 5 wt% for heating treatment (100 ℃), the product is filtered and then soaked in a sodium hydroxide solution with the concentration of 20 wt% for heating treatment (60 ℃), and then the product is filtered, fully washed and dried to constant weight, so that the activated fibrilia is obtained.

Dissolving cetyl trimethyl ammonium bromide, methanol and diethanolamine in water, heating to 60 deg.C, mixing and stirring for 60 min. The molar ratio of hexadecyl trimethyl ammonium bromide to diethanolamine to methanol to water is controlled to be 0.5: 5: 10: 100.

Adding 3-aminopropyltriethoxysilane and propyl orthosilicate into the mixed system, continuously stirring for 60min at 60 ℃, and controlling the molar ratio of the components 3-aminopropyltriethoxysilane: the ratio of the propyl orthosilicate to the mixed system is 0.6: 1, and the mass volume ratio of the propyl orthosilicate to the mixed system is 7.1%.

Adding 15g of activated fibrilia into the above mixed system at bath ratio of 1: 60, and standing at 60 deg.C for 12 hr.

And filtering and taking out the fibrilia from the mixed system, washing, drying, refluxing for 12h by adopting methanol at the temperature of 60 ℃ under nitrogen, filtering, washing and drying in vacuum to obtain the primary biomass-based mesoporous composite material.

Dispersing 15g of the primary composite material in 8 wt% of an organic solvent of a hydroxyl-terminated hyperbranched polymerAnd (3) carrying out stirring reaction for 6h at the temperature of 60 ℃ in the agent solution at the bath ratio of 1: 60, filtering the material, taking out, washing and carrying out vacuum drying to obtain the cellulose biomass-based in-situ mesoporous composite material. The material is subjected to organic dye (methylene blue) and heavy metal ion (Cu)²⁺) In static adsorption experiment, the saturated adsorption capacity of methylene blue is 204mg/g, and Cu²⁺The saturated adsorption amount of (2) is 102mg/g, the adsorption-desorption cycle is carried out for 4 times, the average adsorption amount of methylene blue is 152mg/g, and Cu is²⁺The average adsorbed amount of (A) was 74 mg/g.