Magnetic nanocomposite adsorption material, preparation method and application thereof

Abstract

The application provides a kind of magnetic nanometer composite adsorption material and preparation method and application, the method is dissolved in deionized water to obtain mixed solution by C6HN4, Al (NO3) 3, Zn (NO3) 2 And dodecyl benzene sulfonic acid;Fe3O4 Nanoparticles are dispersed in deionized water to obtain dispersion;The dispersion and mixed solution are mixed, and the product is separated after being treated at 115-125 DEG C, then washed, dried, to obtain the LDH nanometer sheet of dodecyl benzene sulfonic acid intercalated with Fe3O4 Coated;It is mixed with HCOONa, C4H6N2 In CH3OH, and the product is washed and dried after being treated at 100-145 DEG C, to obtain the LDH / ZIF-8 magnetic nanometer composite adsorption material of dodecyl benzene sulfonic acid intercalated with Fe3O4 Coated.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of adsorption material preparation, and particularly relates to a magnetic nanocomposite adsorption material and a preparation method and application thereof. BACKGROUND

[0002] The mature fruit of Schisandra chinensis (Magnoliaceae) is rich in chemical components, and the most key effective component is lignans. Schisandrin A, schisantherol, schisantherol B, etc. are the core substances of lignans, and schisandrin A is dominant. As one of natural compounds, lignans can not only improve immunity and myocardial contractility, but also has the effects of analgesia, lipid-lowering, enzyme-lowering, improvement of heart function and respiration, and influence on the excitation and inhibition processes of cerebral cortex.

[0003] For the extraction of lignan compounds in Schisandra chinensis, the earliest extraction methods used are mostly decoction method, organic solvent immersion method, percolation method and hot reflux extraction method, etc. These traditional extraction methods have the advantages of simple operation and low cost, but they all consume a large amount of organic solvent in the extraction process, not only causing environmental problems, but also causing toxic substance residues, and the extraction time is long, which seriously affects the production efficiency.

[0004] Although new lignan extraction methods have been emerging in recent years, such as ultrasonic-assisted extraction method, microwave-assisted extraction method and aqueous two-phase extraction method, etc., these methods can only be carried out in the laboratory and cannot be widely used in large-scale production. SUMMARY

[0005] In view of the technical problems existing in the prior art, the application provides a magnetic nanocomposite adsorption material and a preparation method and application thereof, which can effectively solve the problems of low adsorption performance, long extraction time and organic residue of the existing adsorption materials.

[0006] The application is realized by the following technical scheme:

[0007] A preparation method of a magnetic nanocomposite adsorption material, comprising the following steps:

[0008] Step 1, C6H 12 N4, Al (NO3) 3, Zn (NO3) 2 and dodecylbenzenesulfonic acid are dissolved in deionized water to obtain a mixed solution;

[0009] Fe3O4 nanoparticles are dispersed in deionized water to obtain a dispersion;

[0010] Step 2, the dispersion and the mixed solution are mixed uniformly, wherein the mass ratio of Fe3O4 nanoparticles and Zn(NO3)2 is 5:178, to obtain a precursor solution a, the precursor solution a is treated at 115-125℃, and then the product is separated, washed and dried to obtain LDH nanosheets coated with Fe3O4 intercalated with dodecyl benzene sulfonic acid;

[0011] Step 3, the LDH nanosheets coated with Fe3O4 intercalated with dodecyl benzene sulfonic acid, HCOONa and C4H6N2 are mixed uniformly in CH3OH at a mass ratio of 12:65:(98-118) to obtain a precursor solution b, the precursor solution b is treated at 100-145℃, and then the product is washed and dried to obtain the LDH / ZIF-8 magnetic nanocomposite adsorbent coated with Fe3O4 intercalated with dodecyl benzene sulfonic acid.

[0012] Preferably, the Fe3O4 nanoparticles in step 1 are obtained by the following process:

[0013] FeCl3·6H2O, NH4OAC and C6H5Na3O7 are dissolved in (CH2OH)2, and the ratio of FeCl3·6H2O, NH4OAC, C6H5Na3O7 and (CH2OH)2 is 1.35 g:3.85 g:0.4 g:70 mL, and then the mixture is stirred magnetically at room temperature for 0.5-1 h, and the obtained mixture is reacted at 180-220℃ for 15-17 h to obtain a reaction solution, and then the product in the reaction solution is separated, washed and dried to obtain Fe3O4 nanoparticles.

[0014] Further, the product in the reaction solution is collected by a magnet, washed with C2H5OH and deionized water for 3-5 times in sequence, and dried at 55-65℃ for 11-13 h to obtain Fe3O4 nanoparticles.

[0015] Preferably, in step 1, C6H 12 N4, Al(NO3)3 and Zn(NO3)2 are dissolved in deionized water, and the ratio of Zn(NO3)2 and deionized water is 1.78 g:20 mL to obtain a mixed solution, dodecyl benzene sulfonic acid is dissolved in deionized water at a ratio of 1.96 g:80 mL, and then stirred at room temperature to obtain a clear solution, and then the mixed solution and the clear solution are mixed and stirred magnetically at 40-50℃ for 0.5-1 h to obtain a mixed solution.

[0016] Preferably, in step 1, the Fe3O4 nanoparticles are placed in deionized water and ultrasonic treated for 15-30 min to obtain a dispersion, and then in step 2, the dispersion and the mixed solution are mixed uniformly to obtain a precursor solution a, and the precursor solution a is treated at 115-125℃ for 22-26 h, and finally the product is separated.

[0017] Further, the vacuum filtration product of step 2 is washed with deionized water and C2H5OH for 3-5 times in sequence, and dried at 80-100 DEG C for 14-18 h to obtain LDH nanosheets coated with Fe3O4 intercalated with dodecyl benzene sulfonic acid.

[0018] Preferably, in step 3, the LDH nanosheets coated with Fe3O4 intercalated with dodecyl benzene sulfonic acid is added in CH3OH at a ratio of 40 mL:0.12 g, then ultrasonic for 10-20 min, and finally stirred at a speed of 600-700 rpm for 0.5-1 h at room temperature, and then HCOONa and C4H6N2 are added and mixed uniformly.

[0019] Preferably, in step 3, the precursor solution b is incubated at 100-145 DEG C for 4.5-5.5 h, then washed with CH3OH, and dried at 50-70 DEG C for 12-14 h to obtain the LDH / ZIF-8 magnetic nanocomposite adsorbent coated with Fe3O4 intercalated with dodecyl benzene sulfonic acid.

[0020] The LDH / ZIF-8 magnetic nanocomposite adsorbent coated with Fe3O4 intercalated with dodecyl benzene sulfonic acid is prepared by the method of any one of the above.

[0021] The application of the LDH / ZIF-8 magnetic nanocomposite adsorbent coated with Fe3O4 intercalated with dodecyl benzene sulfonic acid in adsorbing lignans.

[0022] Compared with the prior art, the application has the following beneficial technical effects:

[0023] The application discloses a preparation method of a magnetic nanocomposite adsorbent. 2+ The application discloses a preparation method of a magnetic nanocomposite adsorbent.

[0024] The Fe3O4@LABSA-LDH / ZIF-8 adsorption material prepared by the application can alleviate the interference of complex sample matrix effects, compared with existing adsorption materials, has the advantages of less solvent consumption, high recovery rate and less toxic residues, is not only conducive to environmental protection, but also simplifies the production process. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly explain the technical solutions of the embodiments of the application, the drawings needed for the description of the embodiments will be briefly described below. Obviously, the following drawings are only part of the embodiments of the application.

[0026] Figure 1 The transmission electron microscope image of Fe3O4 prepared for the embodiment 1 of the application.

[0027] Figure 2 The transmission electron microscope image of Fe3O4@LABSA-LDH prepared for the embodiment 1 of the application.

[0028] Figure 3 The transmission electron microscope image of Fe3O4@LABSA-LDH / ZIF-8 prepared for the embodiment 1 of the application. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the embodiments of the application become clear at a glance, the technical solutions in the embodiments of the application will be described in detail below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are part of the application rather than all. Based on the embodiments in the application, all other embodiments obtained by a person skilled in the art without any creative labor are within the scope of protection of the application.

[0030] The application will be described in further detail below with reference to the drawings and specific embodiments, which are an explanation rather than a limitation of the application.

[0031] LDHs full name for layered double hydroxide, is Layered double hydroxides Abbreviation, refers to a kind of by positive charged metal hydroxide layer group's layered inorganic material, in which the anion of charge balance is inserted between each layer.Because this special structure makes LDHs have good anion exchange capacity and composition activity.ZIFs full name for zeolitic imidazolate frameworks, is Zeolitic imidazolate frameworks Abbreviation, refers to a kind of metal node is connected by coordination bond and imidazole acid salt inorganic-organic microporous crystal hybrid material.ZIFs exist than surface area, pore size adjustable, functional flexible characteristics.Both because of its unique structure morphology and physical and chemical properties in many nanomaterials are concerned, also in food, biology, environment sample extraction has been widely used.

[0032] The application provides a preparation method of a magnetic nano composite adsorption material based on LABSA-LDH / ZIF-8, comprising the following steps:

[0033] Step one, Fe3O4 nanoparticles are synthesized by a citric acid hydrothermal method:

[0034] (1) 1.35 g of FeCl3·6H2O, 3.85 g of NH4OAC and 0.4 g of C6H5Na3O7 are dissolved in 70 mL of (CH2OH)2;

[0035] (2) magnetic stirring is carried out at room temperature for 0.5-1 h;

[0036] (3) the mixed solution is transferred to a Teflon stainless steel autoclave, and reaction is carried out at 180-220 DEG C for 15-17 h;

[0037] (4) after reaction is completed, the black reaction product is collected by a magnet after natural cooling to room temperature;

[0038] (5) the collected reaction product is washed with 35-45 mL of C2H5OH and deionized water for 3-5 times in sequence;

[0039] (6) finally, the product is dried at 55-65 DEG C for 11-13 h for standby use.

[0040] Step two, Fe3O4@LABSA-LDH nanoparticles are prepared by a hydrothermal method:

[0041] (1) first, 1.4 g (0.01 mol) of C6H 12 N4, 0.75 g (0.002 mol) of Al (NO3) 3 and 1.78 g (0.006 mol) of Zn (NO3) 2 are dissolved in 20 mL of deionized water;

[0042] (2) 1.96 g (0.006 mol) of LABSA (i.e. dodecylbenzenesulfonic acid) was dissolved in 80 mL of deionized water, and stirred at room temperature to obtain a clear solution;

[0043] After mixing the above two solutions, magnetic stirring was carried out at 40-50°C for 0.5-1 h to obtain solution a;

[0044] (3) 50 mg of Fe3O4 nanoparticles was placed in 40 mL of deionized water and ultrasonicated for 15 min to obtain dispersion a;

[0045] (4) Finally, solution a and dispersion a were mixed uniformly and placed in a Teflon stainless steel autoclave, and then incubated in an oven at 115-125°C (i.e. hydrothermal reaction) for 22-26 h;

[0046] (5) The obtained product was vacuum filtered, washed with 35-45 mL of deionized water and C2H5OH for 3-5 times, and dried at 80-100°C for 14-18 h.

[0047] Step three, preparation of Fe3O4@LABSA-LDH / ZIF-8:

[0048] (1) First, 0.12 g of Fe3O4@LABSA-LDH was added to 40 mL of CH3OH and ultrasonicated for 10-20 min, and stirred at room temperature at a speed of 600-700 rpm for 0.5-1 h;

[0049] (2) Then, 0.65 g of HCOONa and 0.98-1.18 g of C4H6N2 were added to the above solution and mixed uniformly;

[0050] (3) The solution was transferred into a Teflon stainless steel autoclave and heated at 100-145°C for 4.5-5.5 h;

[0051] (4) The obtained product was washed with 35-45 mL of CH3OH for 3-5 times, and dried at 50-70°C for 12-14 h.

[0052] Example 1

[0053] A magnetic nanocomposite adsorption material based on LABSA-LDH / ZIF-8, as well as a preparation method and application thereof, comprises the following steps:

[0054] Step 1: 1.35 g FeCl3·6H2O, 0.4 g C6H5Na3O7, 3.85 g NH4OAC were dissolved in 70 mL (CH2OH)2. After stirring at room temperature for 1 h, the mixed solution was transferred to a Teflon stainless steel autoclave and reacted at 200℃ for 16 h. After the reaction was completed, it was naturally cooled to room temperature and the black reaction product was collected with a magnet. The collected reaction product was washed with 45 mL deionized water and C2H5OH for 4 times, respectively. The final product was dried at 60℃ for 12 h for standby;

[0055] Step 2: 1.4 g C6H 12 N4, 0.75 g Al(NO3)3 and 1.78 g Zn(NO3)2 were first dissolved in 20 mL deionized water. Then 1.96 g LABSA was dissolved in 80 mL deionized water to obtain a clear solution by stirring at room temperature;

[0056] After mixing the above two solutions, 50 mg Fe3O4 nanoparticles were added to 40 mL deionized water and ultrasonic for 15 min to obtain dispersion a. Finally, solution a and dispersion a were mixed uniformly and placed in a Teflon stainless steel autoclave and reacted in a 120℃ oven for 24 h. The obtained product was vacuum filtered and washed with 40 mL deionized water and C2H5OH for 3 times, respectively, and dried at 80℃ for 16 h.

[0057] Step 3: First, 0.12 g Fe3O4@LABSA-LDH was added to 40 mL CH3OH and ultrasonic for 15 min, and stirred at a speed of 700 rpm at room temperature for 0.5 h. Then 0.65 g HCOONa and 0.98 g C4H6N2 were added to the above solution and mixed uniformly, and the solution was transferred to a Teflon stainless steel autoclave and heated at 100℃ for 5 h. The obtained product was washed with 35 mL CH3OH for 5 times and dried at 60℃ for 12 h.

[0058] Example 2

[0059] A LABSA-LDH / ZIF-8-based magnetic nanocomposite adsorbent material and a preparation method and application thereof, comprising the following steps:

[0060] Step 1: 1.35 g FeCl3·6H2O, 0.4 g C6H5Na3O7, 3.85 g NH4OAC were dissolved in 70 mL (CH2OH)2. After stirring at room temperature for 1 h, the mixed solution was transferred to a Teflon stainless steel autoclave and reacted at 210℃ for 15 h. After the reaction was completed, it was naturally cooled to room temperature and the black reaction product was collected with a magnet. The collected reaction product was washed with 45 mL deionized water and C2H5OH for 4 times, respectively. The final product was dried at 60℃ for 12 h for standby;

[0061] Step 2: 1.4 g C6H 12 N4, 0.75 g Al(NO3)3 and 1.78 g Zn(NO3)2 were first dissolved in 20 mL deionized water. Then 1.96 g LABSA was dissolved in 80 mL deionized water to obtain a clear solution by stirring at room temperature;

[0062] After mixing the above two solutions, 50 mg Fe3O4 nanoparticles were added to 40 mL deionized water and ultrasonic for 15 min to obtain dispersion a. Finally, solution a and dispersion a were mixed uniformly and placed in a Teflon stainless steel autoclave and reacted in a 120℃ oven for 24 h. The obtained product was vacuum filtered and washed with 40 mL deionized water and C2H5OH for 3 times, respectively, and dried at 100℃ for 14 h.

[0063] Step 3: First, 0.12 g Fe3O4@LABSA-LDH was added to 40 mL CH3OH and ultrasonic for 15 min, and stirred at a speed of 700 rpm at room temperature for 0.5 h. Then 0.65 g HCOONa and 0.98 g C4H6N2 were added to the above solution and mixed uniformly, and the solution was transferred to a Teflon stainless steel autoclave and heated at 100℃ for 5 h. The obtained product was washed with 35 mL CH3OH for 5 times and dried at 60℃ for 12 h.

[0064] Example 3

[0065] A LABSA-LDH / ZIF-8-based magnetic nanocomposite adsorbent material and a preparation method and application thereof, comprising the following steps:

[0066] Step 1: 1.35 g FeCl3·6H2O, 0.4 g C6H5Na3O7, 3.85 g NH4OAC were dissolved in 70 mL (CH2OH)2. After stirring at room temperature for 1 h, the mixed solution was transferred into a Teflon stainless steel autoclave and reacted at 180℃ for 17 h. After the reaction was completed, it was naturally cooled to room temperature and the black reaction product was collected with a magnet. The collected reaction product was washed with 45 mL deionized water and C2H5OH for 4 times, respectively. The final product was dried at 60℃ for 12 h for standby;

[0067] Step 2: 1.4 g C6H 12 N4, 0.75 g Al(NO3)3 and 1.78 g Zn(NO3)2 were first dissolved in 20 mL deionized water. Then 1.96 g LABSA was dissolved in 80 mL deionized water to obtain a clear solution by stirring at room temperature;

[0068] After mixing the above two solutions, 50 mg Fe3O4 nanoparticles were added to 40 mL deionized water and ultrasonic for 15 min to obtain dispersion a. Finally, solution a and dispersion a were mixed uniformly and placed in a Teflon stainless steel autoclave and reacted in a 125℃ oven for 22 h. The obtained product was vacuum filtered and washed with 40 mL deionized water and C2H5OH for 3 times, respectively, and dried at 100℃ for 16 h.

[0069] Step 3: First, 0.12 g Fe3O4@LABSA-LDH was added to 40 mL CH3OH and ultrasonic for 15 min, and stirred at a speed of 700 rpm at room temperature for 0.5 h. Then 0.65 g HCOONa and 1.08 g C4H6N2 were added to the above solution and mixed uniformly, and the solution was transferred into a Teflon stainless steel autoclave and heated at 100℃ for 5 h. The obtained product was washed with 35 mL CH3OH for 5 times and dried at 60℃ for 12 h.

[0070] Example 4

[0071] A LABSA-LDH / ZIF-8-based magnetic nanocomposite adsorption material and a preparation method and application thereof, comprising the following steps:

[0072] Step 1: 1.35 g FeCl3·6H2O, 0.4 g C6H5Na3O7, 3.85 g NH4OAC were dissolved in 70 mL (CH2OH)2. After stirring at room temperature for 1 h, the mixed solution was transferred to a Teflon stainless steel autoclave and reacted at 200℃ for 16 h. After the reaction was completed, it was naturally cooled to room temperature and the black reaction product was collected with a magnet. The collected reaction product was washed with 45 mL deionized water and C2H5OH for 4 times, respectively. The final product was dried at 60℃ for 12 h for standby;

[0073] Step 2: 1.4 g C6H 12 N4, 0.75 g Al(NO3)3 and 1.78 g Zn(NO3)2 were first dissolved in 20 mL deionized water. Then 1.96 g LABSA was dissolved in 80 mL deionized water to obtain a clear solution by stirring at room temperature;

[0074] After mixing the above two solutions, 50 mg Fe3O4 nanoparticles were added to 40 mL deionized water and ultrasonic for 15 min to obtain dispersion a. Finally, solution a and dispersion a were mixed uniformly and placed in a Teflon stainless steel autoclave and reacted in a 120℃ oven for 24 h. The obtained product was vacuum filtered and washed with 40 mL deionized water and C2H5OH for 3 times, respectively, and dried at 100℃ for 16 h.

[0075] Step 3: First, 0.12 g Fe3O4@LABSA-LDH was added to 40 mL CH3OH and ultrasonic for 15 min, and stirred at a speed of 700 rpm at room temperature for 0.5 h. Then 0.65 g HCOONa and 1.08 g C4H6N2 were added to the above solution and mixed uniformly, and the solution was transferred to a Teflon stainless steel autoclave and heated at 120℃ for 5 h. The obtained product was washed with 35 mL CH3OH for 5 times and dried at 60℃ for 12 h.

[0076] Example 5

[0077] A LABSA-LDH / ZIF-8-based magnetic nanocomposite adsorbent material and a preparation method and application thereof, comprising the following steps:

[0078] Step 1: 1.35 g FeCl3·6H2O, 0.4 g C6H5Na3O7, 3.85 g NH4OAC were dissolved in 70 mL (CH2OH)2. After stirring at room temperature for 1 h, the mixed solution was transferred to a Teflon stainless steel autoclave and reacted at 200℃ for 16 h. After the reaction was completed, it was naturally cooled to room temperature and the black reaction product was collected with a magnet. The collected reaction product was washed with 45 mL deionized water and C2H5OH for 4 times, respectively. The final product was dried at 60℃ for 12 h for standby;

[0079] Step 2: 1.4 g C6H 12 N4, 0.75 g Al(NO3)3 and 1.78 g Zn(NO3)2 were dissolved in 20 mL deionized water. Then 1.96 g LABSA was dissolved in 80 mL deionized water to obtain a clear solution by stirring at room temperature;

[0080] After mixing the above two solutions, solution a was obtained by stirring at 45℃ for 60 min. 50 mg Fe3O4 nanoparticles were added to 40 mL deionized water and ultrasonic for 15 min to obtain dispersion a. Finally, solution a and dispersion a were mixed uniformly and placed in a Teflon stainless steel autoclave and reacted in a 120℃ oven for 24 h. The obtained product was vacuum filtered and washed with 40 mL deionized water and C2H5OH for 3 times, respectively, and dried at 100℃ for 16 h.

[0081] Step 3: First, 0.12 g Fe3O4@LABSA-LDH was added to 40 mL CH3OH and ultrasonic for 15 min, and stirred at room temperature at a speed of 700 rpm for 0.5 h. Then 0.65 g HCOONa and 1.18 g C4H6N2 were added to the above solution and mixed uniformly, and the solution was transferred to a Teflon stainless steel autoclave and heated at 120℃ for 5 h. The obtained product was washed with 35 mL CH3OH for 5 times and dried at 60℃ for 12 h.

[0082] Example 6

[0083] A LABSA-LDH / ZIF-8-based magnetic nanocomposite adsorbent material and a preparation method and application thereof, comprising the following steps:

[0084] Step 1: 1.35 g FeCl3-6H2O, 0.4 g C6H5Na3O7, 3.85 g NH4OAC were dissolved in 70 mL (CH2OH)2. After stirring at room temperature for 1 h, the mixed solution was transferred into a Teflon stainless steel autoclave and reacted at 200 °C for 16 h. After the reaction was completed, it was naturally cooled to room temperature and the black reaction product was collected with a magnet. The collected reaction product was washed with 45 mL deionized water and C2H5OH for 4 times, respectively. The final product was dried at 60 °C for 12 h for standby;

[0085] Step 2: 1.4 g C6H 12 N4, 0.75 g Al (NO3)3and 1.78 g Zn (NO3)2were first dissolved in 20 mL deionized water. Then 1.96 g LABSA was dissolved in 80 mL deionized water to obtain a clear solution by stirring at room temperature;

[0086] After mixing the above two solutions, solution a was obtained by stirring at 45 °C for 60 min. 50 mg Fe3O4nanoparticles were added to 40 mL deionized water and ultrasonic for 15 min to obtain dispersion a. Finally, solution a and dispersion a were mixed uniformly and placed in a Teflon stainless steel autoclave and reacted in a 120 °C oven for 24 h. The obtained product was vacuum filtered and washed with 40 mL deionized water and C2H5OH for 3 times, respectively, and dried at 100 °C for 16 h.

[0087] Step 3: First, 0.12 g Fe3O4@LABSA-LDH was added to 40 mL CH3OH and ultrasonic for 15 min, and stirred at room temperature at a speed of 700 rpm for 0.5 h. Then 0.65 g HCOONa and 1.18 g C4H6N2were added to the above solution and mixed uniformly, and the solution was transferred into a Teflon stainless steel autoclave and heated at 145 °C for 4.5 h. The obtained product was washed with 35 mL CH3OH for 5 times and dried at 60 °C for 12 h.

[0088] Comparative Example: Fe3O4@ZnAl-LDH / ZIF-8

[0089] Step 1: 1.35 g FeCl3·6H2O, 0.4 g C6H5Na3O7, 3.85 g NH4OAC were dissolved in 70 mL (CH2OH)2. After stirring at room temperature for 1 h, the mixed solution was transferred to a Teflon stainless steel autoclave and reacted at 200℃ for 16 h. After the reaction was completed, it was naturally cooled to room temperature and the black reaction product was collected with a magnet. The collected reaction product was washed with 45 mL deionized water and C2H5OH for 4 times, respectively. The final product was dried at 60℃ for 12 h for standby;

[0090] Step 2: 1.4 g C6H 12 N4, 0.75 g Al(NO3)3 and 1.78 g Zn(NO3)2 were first dissolved in 20 mL deionized water. 50 mg Fe3O4 nanoparticles were added to 40 mL deionized water and ultrasonicated for 15 min. Finally, it was mixed and placed in a Teflon stainless steel autoclave and reacted in a 120℃ oven for 24 h. The product was obtained by vacuum filtration, washed with 40 mL deionized water and C2H5OH for 5 times, and dried at 90℃ for 16 h to obtain Fe3O4@LDH.

[0091] Step 3: First, 0.12 g Fe3O4@LDH was added to 40 mL CH3OH and ultrasonicated for 15 min, and stirred at room temperature at a speed of 650 rpm. Then 0.65 g HCOONa and 1.18 g C4H6N2 were added to the above solution, and the resulting solution was transferred to a Teflon stainless steel autoclave and heated at 100℃ for 5 h to obtain the product. The product was washed with 40 mL CH3OH for 4 times and dried at 60℃ for 12 h.

[0092] Performance test

[0093] The adsorbent material prepared by the control example Fe3O4@ZnAl-LDH / ZIF-8 in the present application is denoted as the control group;

[0094] The adsorbent materials prepared by Examples 1-6 are denoted as Examples 1-6, and then the control group and Examples 1-6 are subjected to the following process of adsorption performance detection.

[0095] The five standard samples of schisandrin A, schisandrin B, schisantherin A, deoxyschizandrin and schisantherin B were dissolved in methanol as solvent to prepare a single standard stock solution with a concentration of 1 mg / mL. The standard stock solution of each analyte was mixed and diluted by methanol to obtain a mixed standard solution of 100 μg / mL. 1 mL of the mixed standard solution was taken, 9 mL of deionized water was added, and the mixed standard solution of 100 μg / mL was prepared into a mixed working solution of 10 μg / mL (the concentration of each substance in the working solution was 10 μg / mL) for lignan adsorption. Six portions of the obtained 20 mg magnetic nanocomposite adsorbent (which can be regarded as a magnetic adsorbent, namely examples 1-6) were dispersed into 1 mL of the mixed working solution (10 μg / mL) and vortexed for 20 min to completely capture the analyte. Then, the magnetic adsorbent after enrichment of the above lignans was separated by an external magnet, and the obtained supernatant was filtered by a 0.22 μm nylon filter membrane and used for HPLC analysis. Under the conditions of ultraviolet light at a wavelength of 230 nm and 30°C, the adsorption was continuously carried out at a flow rate of 1 mL / min, and the injection volume was 10 μL until the adsorption amount no longer changed. The obtained data are recorded in Table 1:

[0096]

[0097] From the data shown in Table 1, it can be seen that the adsorbent prepared in examples 1-6 has a higher saturated adsorption capacity compared with the control group, which indicates that the addition of LABSA makes the adsorbent have better adsorption performance and higher adsorption capacity. Secondly, the saturated adsorption capacity of the adsorbent prepared in examples 1-6 gradually increases, because the increase of the amount of C4H6N2, the stirring time and the reaction temperature leads to the increase of the final adsorption performance, so that the saturated adsorption capacity of the mixed standard solution increases. As can be seen, the Fe3O4@LABSA-LDH / ZIF-8 magnetic nanocomposite adsorbent prepared in the present application has the morphology characteristics as shown in Figure 3 The bare Fe3O4 particles are uniform and smooth spherical structures ( Figure 1 ). After successfully coating the intercalated LABSA-LDH nanosheets on the surface of Fe3O4 ( Figure 2 ), a cluster-like lamellar morphology is presented. As can be seen in Figure 3 , the special zeolite structure belonging to the ZIF-8 crystal appears on the surface of the nanomaterial, which indicates that the ZIF-8 crystal is successfully coated on the LABSA-LDH layer. The performance in adsorption is more excellent, and the application prospect is better.

[0098] The above examples are only used to illustrate the technical solutions of the present application, and are not intended to limit the present application; although the present application is clearly described with reference to the above examples, those skilled in the art should understand that equivalent transformations, modifications, substitutions and deformations can be made to the examples without departing from the spirit and scope of the technical solutions of the embodiments of the present application, and the scope of the present application is defined by the appended claims.

Claims

1. The use of a Fe3O4-coated LDH / ZIF-8 magnetic nanocomposite adsorbent material intercalated with dodecylbenzenesulfonic acid in the adsorption of lignans, characterized in that, The preparation method of the magnetic nanocomposite adsorbent material includes the following steps: Step 1, C6H 12 N4, Al(NO3)3, Zn(NO3)2and dodecyl benzene sulfonic acid were dissolved in deionized water to obtain a mixed solution; Fe3O4 nanoparticles were dispersed in deionized water to obtain a dispersion. Step 2: Mix the dispersion and the mixed solution evenly, wherein the mass ratio of Fe3O4 nanoparticles to Zn(NO3)2 is 5:178 to obtain precursor solution a. Precursor solution a is kept at 115-125℃. After separating the product, it is washed and dried to obtain LDH nanosheets with Fe3O4 coated and intercalated with dodecylbenzenesulfonic acid. Step 3: At a mass ratio of 12:65:(98-118), LDH nanosheets coated with Fe3O4 and intercalated with dodecylbenzenesulfonic acid, HCOONa and C4H6N2 are mixed evenly in CH3OH to obtain precursor solution b. Precursor solution b is kept at 100-145℃, and then the product is washed and dried to obtain LDH / ZIF-8 magnetic nanocomposite adsorbent material coated with Fe3O4 and intercalated with dodecylbenzenesulfonic acid.

2. The use of the LDH / ZIF-8 magnetic nanocomposite adsorbent material coated with Fe3O4 intercalated with dodecylbenzenesulfonic acid of claim 1 in adsorbing lignans, characterized in that, The Fe3O4 nanoparticles mentioned in step 1 are obtained through the following process: FeCl3·6H2O, NH4OAC, and C6H5Na3O7 were dissolved in (CH2OH)2 in a ratio of 1.35 g: 3.85 g: 0.4 g: 70 mL. The mixture was then magnetically stirred at room temperature for 0.5–1 h. The resulting mixture was then reacted at 180–220 °C for 15–17 h to obtain a reaction solution. The products in the reaction solution were then separated, washed, and dried to obtain Fe3O4 nanoparticles.

3. The application of the LDH / ZIF-8 magnetic nanocomposite adsorbent material with Fe3O4 coating and dodecylbenzenesulfonic acid intercalation as described in claim 2 in the adsorption of lignans, characterized in that, The product in the reaction solution was collected using a magnet, washed 3-5 times with C2H5OH and deionized water, and dried at 55-65℃ for 11-13 h to obtain Fe3O4 nanoparticles.

4. The application of the LDH / ZIF-8 magnetic nanocomposite adsorbent material with Fe3O4 coating and dodecylbenzenesulfonic acid intercalation as described in claim 1 in the adsorption of lignans, characterized in that, Step 1 C6H 12 N4, Al(NO3)3 and Zn(NO3)2 were dissolved in deionized water, the ratio of Zn(NO3)2 and deionized water was 1.78 g:20 mL, to obtain a mixed solution, dodecylbenzenesulfonic acid was dissolved in deionized water at a ratio of 1.96 g:80 mL, then stirred at room temperature to obtain a clear solution, the mixed solution and the clear solution were mixed, and then stirred magnetically at 40-50°C for 0.5-1 h to obtain a mixed solution.

5. The application of the LDH / ZIF-8 magnetic nanocomposite adsorbent material with Fe3O4 coating and dodecylbenzenesulfonic acid intercalation as described in claim 1 in the adsorption of lignans, characterized in that, Step 1: Fe3O4 nanoparticles are placed in deionized water and sonicated for 15-30 min to obtain a dispersion. Then, in Step 2, the dispersion and the mixed solution are mixed evenly. The resulting precursor solution a is kept at 115-125℃ for 22-26 h, and finally the product is separated.

6. The application of the LDH / ZIF-8 magnetic nanocomposite adsorbent material with Fe3O4 coating and dodecylbenzenesulfonic acid intercalation as described in claim 5 in the adsorption of lignans, characterized in that, Step 2: Vacuum filter the product, wash it with deionized water and C2H5OH 3-5 times in sequence, and dry it at 80-100℃ for 14-18 h to obtain LDH nanosheets with Fe3O4 coating and intercalated with dodecylbenzenesulfonic acid.

7. The application of the LDH / ZIF-8 magnetic nanocomposite adsorbent material with Fe3O4 coating and dodecylbenzenesulfonic acid intercalation according to claim 1 in the adsorption of lignans, characterized in that, In step 3, at a ratio of 40 mL: 0.12 g, first add LDH nanosheets coated with Fe3O4 and intercalated with dodecylbenzenesulfonic acid to CH3OH, then sonicate for 10-20 min, and finally stir at 600-700 rpm for 0.5-1 h at room temperature, then add HCOONa and C4H6N2 and mix evenly.

8. The application of the LDH / ZIF-8 magnetic nanocomposite adsorbent material with Fe3O4 coating and dodecylbenzenesulfonic acid intercalation as described in claim 1 in the adsorption of lignans, characterized in that, Step 3: The precursor solution b is kept at 100-145℃ for 4.5-5.5 h, then washed with CH3OH and dried at 50-70℃ for 12-14 h to obtain an LDH / ZIF-8 magnetic nanocomposite adsorbent material with Fe3O4 coated and intercalated with dodecylbenzenesulfonic acid.

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