Hydrogen bond donor-acceptor-containing metal organic framework material for adsorbing histamine based on strong hydrogen-bond interaction

Abstract

The invention provides a hydrogen bond donor-acceptor-containing metal organic framework material adsorbing histamine based on strong hydrogen bond interaction and a preparation method thereof. According to the invention, a hydrothermal method is adopted to synthesize the metal organic framework material containing hydrogen bond donors and acceptors, the adsorption performance of the material on histamine is evaluated under the conditions of 40 DEG C and 101 kPa, and experimental results show that the maximum adsorption capacity of UiO-66-2COOH is 135.81 mg / g. The adsorption process accords with a linear Langmuir isotherm model and a quasi-secondary kinetic model. Zeta potential analysis shows that electrostatic interaction exists before and after adsorption. The physical and chemical properties of the materials are represented in detail through X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscope, thermogravimetric analysis and other technologies, the cycle stability of the materials in five adsorption-desorption cycles is evaluated, and the result shows that the material has good performance and potential industrial application prospects.

Description

Technical Field

[0001] The invention relates to the field of adsorption materials for aquatic product corruption products, and in particular to a metal organic framework material containing hydrogen bond donors and acceptors for adsorbing volatile histamine based on strong hydrogen bonding, and a preparation method thereof. Background Art

[0002] Due to their unique living environment, aquatic products are rich in nutrients such as protein, unsaturated fatty acids, vitamins, minerals, etc., and have health benefits such as brain-boosting, controlling and assisting in adjusting blood pressure, blood sugar, blood lipids, and anti-cancer, providing humans with high-quality nutritional supplements. However, aquatic products are perishable and denatured after death, and are prone to forming corrupt compounds such as organic acids, aldehydes and ketones, alcohols, sulfides, and biogenic amines. Histamine, as a type of biogenic amine, can accumulate in foods such as marine fish, cheese, and crabs through the decarboxylation of L-histidine, and is rapidly formed under the action of enzymes and microorganisms. Among the biogenic amines ingested in food, histamine is the most toxic. It can act as a neurotransmitter and vasodilator, causing headaches, hypotension, palpitations, asthma attacks, as well as skin flushing and gastrointestinal disorders. At the same time, histamine is resistant to high temperatures and has good solubility, and it is difficult to remove histamine by general cooking methods.

[0003] Researchers have invested a lot of effort in controlling the formation of histamine in fish. So far, the growth of histamine-producing microorganisms during fish preservation has been inhibited mainly by freezing, drying or pickling. However, when temperature fluctuations or secondary microbial contamination occur during storage, histamine will still be produced after heat treatment of fish. In addition, histamine is also produced in lower pH environments due to the formation of some salt-tolerant or halophilic histamine-producing microorganisms. The results show that conventional processing and preservation methods such as pickling, drying, fermentation, smoking and pickling can also promote histamine formation. Therefore, there is an urgent need to develop new technologies and materials to remove histamine from aquatic products in a targeted and efficient manner.

[0004] Compared with microbial control methods, adsorption technology has low cost, simple operation and high removal rate. Among them, there are many types of adsorbents, including zeolites, magnetic materials, nanofiber materials, etc., which are ideal methods for removing target substances. MOF materials are porous materials with specific crystal structures formed by the interconnection of inorganic metal ions (or metal clusters) and organic ligands. They are very attractive in the field of selective separation due to their high porosity, multifunctional pore structure and adjustable pore size. Metal-organic framework (MOF) materials, including original MOF, functionalized MOF and MOF-derived materials, have been studied in depth to explore their adsorption performance for various organic substances. In 2008, a rigid metal-organic framework material with Zr as the metal center and terephthalic acid (H2BDC) as the organic ligand was first reported, named UiO-66. UiO-66 has excellent hydrothermal and chemical stability. Its crystal structure can remain stable at 500 °C. It can maintain structural stability in solutions such as water, N,N-dimethylformamide, benzene or acetone. It also has strong acid resistance and certain alkali resistance. The dense structural units make the entire structure stably connected. However, due to the relative inertness of the organic ligands of metal-organic framework materials and the lack of active binding sites, they often show low efficiency, poor selectivity and poor adsorption capacity. Hydrogen bonding is a commonly used mechanism to explain the observed adsorption phenomenon. The contribution of hydrogen bonding significantly increases the adsorption amount of the adsorbate. Under pH>4.5 conditions, aromatic amines exist in a non-protonated form and can act as hydrogen acceptors; while aromatic hydroxyl groups (-OH) can be both hydrogen donors and hydrogen acceptors. At the same time, the hydrogen bond energy between strong hydrogen bonds -OH (or -NH) and -O (or -N) is large, and the enthalpy of hydrogen bonding between OH---N and NH---O reaches 29KJ / mol and 8KJ / mol, respectively. Fortunately, some researchers have found that a unique property of MOFs is that they can be chemically functionalized. Therefore, synthesizing metal organic framework materials with hydrogen bond acceptor or donor properties by selecting exothermic ligands with special functional groups, aiming to efficiently remove histamine through hydrogen bonding, is a new material direction worth exploring. Summary of the invention

[0005] In view of the above problems, the present invention aims to provide a preparation method and application of a metal organic framework material containing hydrogen bond donors and acceptors for adsorbing histamine. As a new adsorbent, acetic acid is used as a regulator, zirconium tetrachloride is used as a zirconium source, and functionalized ligands derived from terephthalic acid (pyromellitic acid, trimesic acid, 2-methylterephthalic acid) are used to synthesize three metal organic framework materials containing hydrogen bond donors and acceptors by a solvothermal method: UiO-66-2COOH, UiO-66-COOH and UiO-66-CH3. The adsorption capacities of the synthesized MOFs for histamine are: 135.81 mg / g for UiO-66-2COOH, 130.53 mg / g for UiO-66-COOH, and 105.88 mg / g for UiO-66-CH3. UiO-66-2COOH shows the highest adsorption capacity, which is attributed to the strong hydrogen bonding between its carboxylic acid group and histamine. The adsorption process conforms to the monolayer chemical adsorption mechanism, and the zeta potential measurement results further confirm the electrostatic interaction between the carboxyl and amino groups. In addition, the metal-organic framework exhibits anti-interference ability, regeneration ability, and a wide range of responses to various biogenic amines. The synthesized metal-organic framework materials show strong potential in effectively adsorbing histamine, indicating that they have broad prospects in industrial applications to prevent histamine accumulation in the early spoilage stage of fish products.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] As the first invention purpose of the present invention:

[0008] Provided is a metal organic framework material containing a hydrogen bond donor and acceptor. The metal organic framework material is synthesized from zirconium tetrachloride and TPA series ligand-pyromellitic acid by a solvent thermal method.

[0009] As the second invention purpose of the present invention:

[0010] A method for preparing a metal organic framework material containing a hydrogen bond donor and acceptor is provided, which specifically comprises the following steps:

[0011] Step 1: Under the action of ultrasound, fully dissolve zirconium tetrachloride and pyromellitic acid;

[0012] Step 2: Transfer the pyromellitic acid solution to a round-bottom flask, add acetic acid as a regulator to control the size of MOF crystals and defects in the crystals, and place on a preheated magnetic stirrer until stirred evenly;

[0013] Step 3: Add the zirconium tetrachloride solution in step 1 dropwise into the solution in step 2, mix well, heat to react, and collect the product after cooling;

[0014] Step 4: washing, centrifuging and drying the reaction product obtained in step 3;

[0015] Step 5: Activate to obtain the UiO-66-2COOH metal organic framework material for subsequent adsorption applications.

[0016] Furthermore, in step 1, the molar ratio of the zirconium source to the organic ligand is 1:1.6; the masses of zirconium tetrachloride and pyromellitic acid are 23.3 mg and 43.2 mg respectively;

[0017] Furthermore, in step 1, the solvents of zirconium tetrachloride and pyromellitic acid are both DMF [N,N-dimethylformamide], and the volume of the solvent is 10 ml;

[0018] Further, in step 2, the volume of the acetic acid regulator is 1 ml;

[0019] Furthermore, in step 2, the preheating temperature of the magnetic stirrer is 120° C., the rotation speed is 200 rpm, and the stirring time is 30 min;

[0020] Furthermore, in step 3, the zirconium tetrachloride solution is added at a speed of about 20 μL / s, the magnetic stirrer is set at a constant temperature of 120° C., a rotation speed of 200 r / min, and a holding time of 24 h;

[0021] Furthermore, in step 4, the detergent is a 95% ethanol solution. The volume ratio of the 95% ethanol solution to the stock solution for the first wash is 1:1, the volume of ethanol added for the second and third washes is 20 ml, the centrifugal speed is 12000 rpm, and the centrifugal time is 20 min. The drying temperature is 70°C and the drying time is 8 h;

[0022] Furthermore, in step 5, the activation temperature is 120° C. and the activation time is 24 hours.

[0023] As the third invention purpose of the present invention:

[0024] Provided is a preparation method for the above-mentioned metal organic framework material containing hydrogen bond donors and acceptors for adsorbing histamine based on strong hydrogen bonding, which specifically comprises the following steps:

[0025] Step S1: A series of adsorbents of different masses are mixed with a histamine solution in proportion to form a reaction system. The mixture is adsorbed and shaken at 298K and 200rpm for 6 hours. After sampling, the mixture is filtered and the concentration of histamine is measured to determine the solid-liquid ratio of the system corresponding to the optimal adsorption capacity; a series of histamine solutions of different concentrations are prepared into a reaction system with an adsorbent solution. The mixture is shaken at 298K and 200rpm for 6 hours. After sampling, the mixture is filtered and the concentration of histamine is measured to determine the histamine concentration corresponding to the optimal adsorption capacity; a series of histamine solutions of different pH values ​​are prepared into a reaction system with an adsorbent solution. The mixture is shaken at 298K and 200rpm for 6 hours. After sampling, the mixture is filtered and the concentration of histamine is measured to determine the pH of the histamine solution corresponding to the optimal adsorption capacity.

[0026] Step S2: The adsorbent and the histamine solution are mixed in proportion to form a reaction system, and samples are taken at different time points to determine the real-time adsorption capacity. The real-time adsorption capacity is calculated by fitting the pseudo-first-order kinetic and pseudo-second-order kinetic models to evaluate the maximum adsorption capacity.

[0027] As a preferred embodiment, in step S1, the solid-liquid ratio system screening preparation method includes: adding 2, 4, 6, 8, 10 and 12 mg of adsorbent to the histamine solution for reaction. The actual specific optimization operation is that the concentration of the histamine solution is 30 mg / L, the volume is 20 ml, and the solvent is water; the solid-liquid ratio of the adsorption system is 0.1, 0.2, 0.3, 0.4 and 0.5 g / L, respectively, and the solid-liquid ratio corresponding to the obtained optimal adsorption capacity is 0.2 g / L. The concentration system screening preparation method includes: adding 5 mg of adsorbent to histamine solutions with concentrations of 30, 40, 50, 100, 150 and 200 mg / L for reaction. The actual specific optimization operation is that the concentration of the histamine stock solution is 1 mg / mL, the volume is 20 ml, and the solvent is water; the histamine solutions of different concentrations are obtained by diluting the histamine stock solution with a concentration of 1 mg / mL with ultrapure water, and the histamine concentration corresponding to the obtained optimal adsorption capacity is 30 mg / L. The pH system screening preparation method includes: adding 5 mg of adsorbent to histamine solutions with pH values ​​of 2, 4, 6, 8, 10 and 12 for reaction. The actual specific optimization operation is to adjust the pH value using HCl and NaOH without significantly changing the overall concentration of the solution, and prepare a 20 mL reaction system. The pH value of the histamine solution corresponding to the optimal adsorption capacity is 7.

[0028] As a preferred embodiment, in step S2, the method for preparing the reaction system comprises: adding 5 mg of adsorbent to the system prepared in the preferred embodiment of step S1 for reaction. The actual specific optimization operation is, after adding 5 mg of adsorbent and 20 mL of histamine solution in sequence, using NaOH and HCl to adjust the pH of the system to 7; then adsorb and oscillate at 298K and 200 rpm for 6 hours, and sample and record the real-time concentration of histamine in the system. The selected time points are 0, 30, 60, 90, 120, 150, 180, 210, 240, 300, 360, 420, 480, 540, 600 min. The histamine concentration is 30 mg / L, and the solvent is water.

[0029] As a preferred embodiment, in step S1 and step S2, dilution and dispersion are performed by ultrasonic treatment to ensure that the adsorbent is evenly distributed in the solution. Subsequently, samples are taken for determination after 6 hours of oscillation adsorption at 25°C. After the sample is filtered, it is used for subsequent analysis. The actual specific optimization operation is to filter the solution using a 0.45μm PES filter and retain 2mL of the sample. The real-time concentration is found by comparing the standard curve of histamine concentration and absorbance. 0, 0.2, 0.4, 0.6, 0.8, 1.0mL of histamine standard solution (equivalent to 0, 4.0, 8.0, 12, 16, 20μg of histamine) and 2mL of sample extract are respectively drawn into a 10mL colorimetric tube, water is added to 1mL, and then 1mL of hydrochloric acid solution is added and mixed. 3mL of sodium carbonate solution and 3mL of azo reagent are added. Add water to the scale, mix, and place for 10min. Transfer the solution in the "0" tube to a 1 cm cuvette, adjust the wavelength of the spectrophotometer to 480 nm, adjust the absorbance to "0", and then test the absorbance of a series of standard solutions and sample solutions in turn, and draw a standard curve with absorbance A as the vertical axis and the mass of histamine as the horizontal axis. The concentration of the sodium carbonate solution is 50 g / L, and the solvent is water; the concentration of the A solution of the azo reagent (p-nitroaniline) is 2.5 g / L, and the solvent is water; the concentration of the B solution of the azo reagent (sodium nitrite solution) is 5 g / L, and the solvent is water; the histamine solutions of different concentrations are obtained by diluting the histamine stock solution with a concentration of 1 mg / mL with ultrapure water.

[0030] As the fourth invention object of the present invention:

[0031] Provided is an application of an adsorbent prepared by a method for preparing a metal organic framework material containing hydrogen bond donors and acceptors in removing histamine, a corruption product in aquatic products.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] (1) The metal organic framework material containing hydrogen bond acceptors / donors prepared by the present invention contains two uncoordinated carboxyl groups, which increase the hydrophilicity of the UiO-66-2COOH adsorbent and promote the contact between the adsorbent and histamine. At the same time, multiple free carboxyl groups, as hydrogen bond acceptors, form strong hydrogen bonds with the amino groups of histamine, such as NH...O (8 kJ / mol) and OH...N (29 kJ / mol), which further improve the adsorption effect, so that the maximum adsorption amount of the adsorbent reaches 135.81 mg / g. Compared with the single hydrogen bond formed by R-OH, the force of the double hydrogen bond is about 7-10 kJ / mol higher. At the same time, the material shows excellent histamine adsorption performance in a large pH range under the condition of less dosage. After the adsorbent material is dispersed in the histamine solution for adsorption equilibrium, it is recovered by centrifugation. The process flow is simple and the operating conditions are easy to achieve.

[0034] (2) When the metal organic framework material containing hydrogen bond acceptors / donors prepared by the present invention is sealed with real spoiled salmon samples, it can detect tyramine produced in spoiled salmon samples. In addition, in a mixed system of histamine and other biogenic amines (such as spermine, tyramine, tryptamine and diamine), the adsorbent also exhibits a wide range of responsiveness.

[0035] (3) When the metal organic framework material containing hydrogen bond acceptors / donors prepared by the present invention is sealed with real spoiled salmon samples, it exhibits good adsorption of volatile biogenic amines such as tyramine produced in spoiled salmon samples. In addition, in a mixed system of histamine and other biogenic amines (such as spermine, tyramine, tryptamine and diamine), the adsorbent also exhibits good responsiveness.

[0036] (4) The metal organic framework material containing hydrogen bond acceptors / donors prepared by the present invention contains two uncoordinated carboxyl groups, which have a relatively negative potential at physiological pH. Through electrostatic interaction, these carboxyl groups can effectively adsorb histamine with positive charge after amino protonation, thereby enhancing its adsorption performance. In addition, there is a π-π interaction between the imidazole ring of histamine and the six-membered ring of the metal organic framework ligand, which further improves the adsorption capacity of histamine. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, and the above and / or other advantages of the present invention will become more clear.

[0038] Figure 1 The following is a synthesis scheme of the adsorbents prepared in Examples 1, 2 and 3 of the present invention.

[0039] Figure 2 a is a scanning electron microscope image of the UiO-66-2COOH adsorbent prepared in Example 1 of the present invention.

[0040] Figure 2 b is a scanning electron microscope image of the UiO-66-COOH adsorbent prepared in Example 2 of the present invention.

[0041] Figure 2 c is a scanning electron microscope image of the UiO-66-CH3 adsorbent prepared in Example 3 of the present invention.

[0042] Figure 2 d is the energy dispersive X-ray spectrum of the UiO-66-2COOH adsorbent prepared in Example 1 of the present invention.

[0043] Figure 2 e is the energy dispersive X-ray spectrum of the UiO-66-COOH adsorbent prepared in Example 2 of the present invention.

[0044] Figure 2 f is the energy dispersive X-ray spectrum of the UiO-66-CH3 adsorbent prepared in Example 3 of the present invention.

[0045] Figure 3 a is the N2 adsorption-desorption curve of the UiO-66-2COOH adsorbent prepared in Example 1 of the present invention.

[0046] Figure 3 b is the N2 adsorption-desorption curve of the UiO-66-COOH adsorbent prepared in Example 2 of the present invention.

[0047] Figure 3 c is the N2 adsorption-desorption curve of the UiO-66-CH3 adsorbent prepared in Example 3 of the present invention.

[0048] Figure 3 d is the Fourier transform infrared spectrum of Examples 1, 2 and 3 of the present invention.

[0049] Figure 3 e is the thermogravimetric analysis diagram of Examples 1, 2 and 3 of the present invention.

[0050] Figure 3 gi is the X-ray diffraction pattern of Examples 1, 2 and 3 of the present invention.

[0051] Figure 3 j is the X-ray photoelectron spectrum of Examples 1, 2 and 3 of the present invention.

[0052] Figure 4 ac is the effect of the solid-liquid ratio of the adsorbent and the adsorption system on the adsorption capacity during the adsorption process of Examples 1-3 of the present invention.

[0053] Figure 4 df is the effect of histamine concentration on the adsorption capacity during the adsorption process of Examples 1-3 of the present invention.

[0054] Figure 4 gi is the effect of the system pH value on the adsorption capacity during the adsorption process of Examples 1-3 of the present invention.

[0055] Figure 5 ac are the pseudo-first-order kinetic and pseudo-second-order kinetic fitting curves of Examples 1-3 of the present invention.

[0056] Figure 5 df is the isothermal adsorption line fitting curve of Examples 1-3 of the present invention.

[0057] Figure 5 gh is the diffusion model fitting curve and the thermodynamic fitting curve of Examples 1-3 of the present invention.

[0058] Figure 6 a is the Zeta potential analysis before and after histamine adsorption of Examples 1-3 of the present invention.

[0059] Figure 6 b is the adsorption result of histamine in the mixture system (NaNO2+histamine, Na2S+histamine, hypoxanthine+histamine and MDA+histamine) of Examples 1-3 of the present invention.

[0060] Figure 6 c is the result of 5 cycles of adsorption and desorption of histamine in Example 1-3 of the present invention

[0061] Figure 6 df are the absorption conditions of volatile biogenic amine substances of actual samples (salmon) of Examples 1-3 of the present invention after 12 hours and 18 hours respectively (the area and intensity of the light spot reflect the change of histamine content). Figure 7 ad are the UV-visible spectra and images of the initial and final concentrations of MO, ARS, MB and RhB adsorbed in Examples 1-3 of the present invention, respectively.

[0062] Table 1 shows the kinetic parameters of histamine adsorption in Examples 1-3.

[0063] Table 2 shows the linear fitting parameters of the interparticle diffusion model for histamine adsorption in Examples 1-3.

[0064] Table 3 shows the isothermal adsorption line fitting parameters of histamine adsorption in Examples 1-3. DETAILED DESCRIPTION

[0065] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0066] Example 1

[0067] A method for preparing a metal organic framework material UiO-66-2COOH containing a hydrogen bond donor acceptor, specifically comprising the following steps:

[0068] (1) Under the action of ultrasound, 23.3 mg of zirconium tetrachloride and 43.2 mg of pyromellitic acid were dissolved in 10 mL and 10 mL of DMF, respectively, and the molar ratio of zirconium source to organic ligand was 1:1.6;

[0069] (2) 10 mL of the 2-methylphthalic acid solution in step (1) was transferred to a 100 mL round-bottom flask and placed on a magnetic stirrer. The mixture was stirred at a constant temperature of 120° C. and a constant speed of 200 rpm. 1 mL of acetic acid was added as a regulator to control the size of the MOF crystals and the number of defects in the crystals until the mixture was stirred evenly.

[0070] (3) adding 20 mL of zirconium tetrachloride solution in step (2) dropwise into the solution in step (2), stirring for 30 min, reacting at 120 ° C. for 24 h, and collecting the product after cooling;

[0071] (4) washing, centrifuging, drying and vacuum activating the reaction product obtained in step (3) to obtain a UiO-66-2COOH metal organic framework material synthesized by a mixed ligand; wherein the drying temperature is 60-70° C. for 18-24 h; and the vacuum activation is performed at 120-180° C. for 10-13 h;

[0072] (5) applying the UiO-66-2COOH metal organic material obtained in step (4) to adsorb and remove histamine in the solution;

[0073] (6) Weigh a certain amount of the UiO-66-2COOH adsorbent prepared in Example 1 into a 30 mL brown glass bottle, add 20 mL of a histamine solution of a certain concentration and a certain pH to the brown glass bottle using a 10 mL pipette, place it on a constant temperature shaker, shake and mix for a certain time at a certain temperature and a speed of 200 r / min, take out the glass bottle, extract 10 mL of the supernatant with a 10 mL syringe without a needle, and filter it with a 0.22 μm filter membrane installed on the syringe. Referring to the national standard GB 5009.208-2016, the concentration of histamine was determined at 480 nm using Shimadzu UV-1900i, and the experimental results were averaged from three groups of data.

[0074] Characterization and analysis of adsorption performance of UiO-66-2COOH in Example 1

[0075] (1) The surface morphology of the UiO-66-2COOH adsorbent was analyzed using a new thermal field emission scanning electron microscope (SEM, SU5000, Hitachi Instruments Co., Ltd., Japan). The results are shown in Figure 2 a;

[0076] Depend on Figure 2 It can be seen from a that UiO-66-2COOH is a spherical particle with a particle size distribution of 80 nm.

[0077] (2) The elemental composition of the adsorbent UiO-66-2COOH (EDS, Aztec, Hitachi Instruments Co., Ltd., Japan) was analyzed by energy dispersive X-ray spectrometry. The results are shown in Figure 2 d;

[0078] Depend on Figure 2 d, it can be seen that UiO-66-2COOH contains elements such as C, O, and Zr, which proves the successful synthesis of the adsorbent.

[0079] (3) N2 adsorption-desorption curve (BET, Quantachorme Quadrasorb SI, Quantachrome Instruments, USA) was used to analyze the pore volume and surface area of ​​the samples. The results are shown in Figure 3 a;

[0080] The N2 adsorption-desorption isotherm of UiO-66-2COOH has no obvious hysteresis loop and shows a typical type I isotherm, indicating that UiO-66-2COOH has a microporous structure.

[0081] (4) The surface functional groups of the obtained product samples were tested using Fourier transform infrared spectrometer (FTIR, Thermo Nicolet iS, Thermo Fisher Scientific, USA). The results are shown in Figure 3 d;

[0082] Depend on Figure 3 d, 1394 and 1587cm -1 The peak at 1700 cm-1 and the C=C group on the benzene ring and the CO vibration on the carboxyl group prove the successful synthesis of the adsorbent. -1 The typical characteristic peak at is attributed to the -C=O of the uncoordinated -COOH in UiO-66-2COOH, indicating the presence of free -COOH groups on the pyromellitic acid linker.

[0083] (5) X-ray photoelectron spectroscopy (XPS, ESCALAB250Xi, Thermo Fisher Scientific, Inc., USA) was used to analyze the elemental composition information of the sample surface. The results are shown in Figure 3 gi;

[0084] In the Zr 3d spectrum, the deconvolution of the peaks is 3 / 2 (185.17 eV) and Zr 3d 5 / 2The X-ray diffraction patterns of the adsorbent were analyzed by X-ray diffraction analysis. ...

[0085] (6) The adsorption performance of UiO-66-2COOH metal framework material was studied by analyzing the kinetic data using pseudo-first-order kinetics and pseudo-second-order kinetics models. Figure 5 a;

[0086] Depend on Figure 5 It can be seen from Table 1 that the correlation coefficient of the pseudo-first-order kinetic model is slightly lower than that of the pseudo-second-order kinetic model. As shown in Table 1, the adsorption amount (125.000 mg / g) calculated by pseudo-second-order kinetics is close to the experimental value (122.958 mg / g), so the adsorption behavior is mainly chemical adsorption.

[0087] (7) The adsorption interaction and surface distribution of histamine between UiO-66-2COOH metal organic framework material and histamine were analyzed by fitting the Langmuir and Freundlich isotherm adsorption models. The results are shown in Figure 5 d;

[0088] Depend on Figure 5 d, the correlation coefficients of the Langmuir model are higher than those of the Freundlich model, indicating that the Langmuir model is more suitable for the adsorption process of histamine by UiO-66-2COOH, indicating that the adsorption process is a single-layer adsorption. As shown in Table 2, at 313.15 K, the values ​​obtained by fitting the Langmuir model are closer to the adsorption capacity obtained in the experiment.

[0089] (8) The potential of UiO-66-2COOH in practical applications was evaluated by testing its Zeta potential, anti-interference property, and recyclability before and after adsorption, as well as its application in real salmon samples. The results are shown in Figure 6 ;

[0090] Depend on Figure 6a It can be seen that UiO-66-2COOH exhibits the highest negative Zeta potential and may contain multiple free carboxyl groups. After adsorbing histamine, the Zeta potential of UiO-66-2COOH increased to varying degrees, indicating that electrostatic interaction may be a feasible mechanism. In order to evaluate its practical application, this study also characterized the anti-interference properties of the composite material. Three typical competing ions or substances were selected: 10 times malondialdehyde (MDA), sodium nitrite (NaNO2), hypoxanthine (Hx) and sodium sulfide (Na2S). These substances are commonly found in spoiled seafood and will interfere with the adsorption of histamine. Figure 6 As shown in (b), despite the presence of these competing substances, the adsorption efficiency of histamine remained above 70%. This indicates that UiO-66MOF has a selective adsorption capacity for histamine in a complex system. After 5 cycles, the removal rate of UiO-66-2COOH remained at about 60%, showing good reproducibility ( Figure 6 c).

[0091] (9) Adsorption experiments were conducted using MB (positively charged, no hydrogen bond donor), RdB (positively charged, hydrogen bond donor), MO (negatively charged, no hydrogen bond donor), and ARS (negatively charged, hydrogen bond donor) to verify the universal adsorption capacity of the material. The results are shown in Figure 7 ;

[0092] like Figure 7 ad, the removal rates of UiO-66-2COOH for different dyes were 57.0% for methyl orange (MO) and 95% for alizarin red S (ARS); it was particularly noteworthy that the adsorbent showed excellent adsorption performance for the cationic dye rhodamine B (RhB), with a removal rate of up to 94%. However, for methylene blue (MB) without hydrogen bond donors, the removal rate was only 42.0%. These results indicate that UiO-66-2COOH can effectively remove dyes containing hydrogen bond donors from wastewater, further confirming the potential of the adsorbent to effectively remove target substances containing hydrogen bond acceptors and donors by enhancing hydrogen bond interactions.

[0093] Example 2 A method for preparing a metal organic framework material containing a hydrogen bond donor acceptor metal organic framework material UiO-66-COOH, specifically comprising the following steps:

[0094] (1) Under the action of ultrasound, 930 mg of zirconium tetrachloride and 850 mg of trimesic acid were dissolved in 20 mL and 20 mL of DMF, respectively, and the molar ratio of the zirconium source to the organic ligand was 1:1;

[0095] (2) Transfer 20 mL of the trimesic acid solution in step (1) to a 100 mL round-bottom flask and place it on a magnetic stirrer, keep the temperature at 120° C. and stir at 200 rpm, and add 1 mL of acetic acid as a regulator to control the size of the MOF crystals and the number of defects in the crystals until the mixture is stirred evenly;

[0096] (3) adding 20 mL of zirconium tetrachloride solution in step (2) dropwise into the solution in step (2), stirring for 30 min, reacting at 120 ° C. for 24 h, and collecting the product after cooling;

[0097] (4) washing, centrifuging, drying, and vacuum activating the reaction product obtained in step (3) to obtain a UiO-66-COOH metal organic framework material synthesized by a mixed ligand; wherein the drying temperature is 60-70° C. for 18-24 h; and the vacuum activation is performed at 120-180° C. for 10-13 h;

[0098] (5) applying the UiO-66-COOH metal organic material obtained in step (4) to adsorb and remove histamine in the solution;

[0099] (6) Weigh a certain amount of the UiO-66-COOH adsorbent prepared in Example 1 into a 30 mL brown glass bottle, add 20 mL of a certain concentration and a certain pH of histamine solution to the brown glass bottle using a 10 mL pipette, place it on a constant temperature shaker, shake and mix for a certain time at a certain temperature and a speed of 200 r / min, take out the glass bottle, extract 10 mL of the supernatant with a 10 mL syringe without a needle, and filter it with a 0.22 μm filter membrane installed on the syringe. Referring to the national standard GB 5009.208-2016, the concentration of histamine was determined at 480 nm using Shimadzu UV-1900i, and the experimental results were averaged from three sets of data.

[0100] Characterization and analysis of adsorption performance of UiO-66-COOH in Example 2

[0101] (1) The surface morphology of the UiO-66-COOH adsorbent was analyzed using a new thermal field emission scanning electron microscope (SEM, SU5000, Hitachi Instruments Co., Ltd., Japan). The results are shown in Figure 2 b;

[0102] Depend on Figure 2 b It can be seen that UiO-66-COOH is a spherical particle with a particle size distribution of 50-60nm.

[0103] (2) The elemental composition of the adsorbent UiO-66-COOH (EDS, Aztec, Hitachi Instruments Co., Ltd., Japan) was analyzed by energy dispersive X-ray spectrometry. The results are shown in Figure 2 e;

[0104] Depend on Figure 2 e It can be seen that UiO-66-COOH contains elements such as C, O, and Zr, which proves the successful synthesis of the adsorbent.

[0105] (3) N2 adsorption-desorption curve (BET, Quantachorme Quadrasorb SI, Quantachrome Instruments, USA) was used to analyze the pore volume and surface area of ​​the samples. The results are shown in Figure 3 b;

[0106] The N2 adsorption-desorption isotherm of UiO-66-COOH has no obvious hysteresis loop and shows a typical type I isotherm, indicating that UiO-66-COOH has a microporous structure.

[0107] (4) The surface functional groups of the obtained product samples were tested using Fourier transform infrared spectrometer (FTIR, Thermo Nicolet iS, Thermo Fisher Scientific, USA). The results are shown in Figure 3 d;

[0108] Depend on Figure 3 d, 1394 and 1587cm -1 The peaks at and the CO vibrations of C=C on the benzene ring and -COOH on the -COOH ring prove the successful synthesis of the adsorbent.

[0109] (5) X-ray photoelectron spectroscopy (XPS, ESCALAB250Xi, Thermo Fisher Scientific, Inc., USA) was used to analyze the elemental composition information of the sample surface. The results are shown in Figure 3 gi;

[0110] In the Zr 3d spectrum, the deconvolution of the peaks is 3 / 2 (185.35 eV) and Zr 3d 5 / 2 The X-ray diffraction patterns of the adsorbent were analyzed by X-ray diffraction (XPS) and X-ray diffraction (XDS) spectra. ...

[0111] (6) The adsorption performance of UiO-66-COOH metal framework material was studied by analyzing the kinetic data using pseudo-first-order kinetics and pseudo-second-order kinetics models. Figure 5 b;

[0112] Depend on Figure 5b It can be seen that the correlation coefficient of the pseudo-first-order kinetic model is slightly lower than that of the pseudo-second-order kinetic model. As shown in Table 1, the adsorption amount calculated by pseudo-second-order kinetics (107.991 mg / g) is close to the experimental value (104.648 mg / g), so the adsorption behavior is mainly chemical adsorption.

[0113] (7) The adsorption interaction and surface distribution of histamine between UiO-66-COOH metal organic framework material and histamine were analyzed by fitting the Langmuir and Freundlich isotherm adsorption models. The results are shown in Figure 5 e;

[0114] Depend on Figure 5 e shows that the correlation coefficients of the Langmuir model are higher than those of the Freundlich model, indicating that the Langmuir model is more suitable for the adsorption process of histamine by UiO-66-COOH, indicating that the adsorption process is a single-layer adsorption. As shown in Table 2, the maximum adsorption capacity obtained by the Langmuir model fitting at 313.15 K is closer to the adsorption capacity obtained in the experiment.

[0115] (8) The potential of UiO-66-COOH in practical applications was evaluated by testing its zeta potential, anti-interference property, and recyclability before and after adsorption, as well as its application in real salmon samples. The results are shown in Figure 6 ;

[0116] Figure 6 a It can be seen that UiO-66-COOH exhibits a low negative Zeta potential and may contain a small amount of free carboxyl groups. The Zeta potential of histamine adsorbed on MOF increased to varying degrees, indicating that electrostatic interaction may be a feasible mechanism. In order to evaluate its practical application, this study also characterized the anti-interference properties of the composite material. Three typical competing ions or substances were selected: 10 times malondialdehyde (MDA), sodium nitrite (NaNO2), hypoxanthine (Hx) and sodium sulfide (Na2S). These substances are common in spoiled seafood and will interfere with the adsorption of histamine. Figure 6 As shown in Fig. 2b, despite the presence of these competing substances, the adsorption efficiency of histamine remained above 74%. This indicates that UiO-66-COOH has a selective adsorption capacity for histamine in a complex system. After 5 cycles, the removal efficiency of UiO-66-COOH remained at about 62%, showing good reproducibility ( Figure 6 c).

[0117] (9) Adsorption experiments were conducted using MB (positively charged, no hydrogen bond donor), RdB (positively charged, hydrogen bond donor), MO (negatively charged, no hydrogen bond donor), and ARS (negatively charged, hydrogen bond donor) to verify the universal adsorption capacity of the material. The results are shown in Figure 7 ;

[0118] like Figure 7 ad, the removal rates of UiO-66-COOH for different dyes were 41.0% for methyl orange (MO), 84.0% for alizarin red S (ARS), 69.0% for rhodamine B (RhB), and only 28.0% for methylene blue (MB) without hydrogen bond donor. These results indicate that UiO-66-COOH performs well in removing dyes with hydrogen bond donors, further confirming its potential to effectively remove target substances containing hydrogen bond acceptors and donors by enhancing hydrogen bond interactions.

[0119] Example 3 A method for preparing a metal organic framework material UiO-66-CH3 containing a hydrogen bond donor and acceptor, specifically comprising the following steps:

[0120] (1) Under the action of ultrasound, 233 mg of zirconium tetrachloride and 360 mg of 2-dimethylphthalic acid were dissolved in 20 mL and 20 mL of DMF, respectively, and the molar ratio of the zirconium source to the organic ligand was 1:1;

[0121] (2) Transfer 20 mL of 2-dimethylphthalic acid solution in step (1) to a 100 mL round-bottom flask and place it on a magnetic stirrer. Stir at 120 °C and 200 rpm. Add 1 mL of acetic acid as a regulator to control the size of MOF crystals and the number of defects in the crystals until the mixture is uniformly stirred.

[0122] (3) Add 20 mL of zirconium tetrachloride solution in step (2) dropwise into the solution in step (2), stir for 30 min, react at 120 °C for 24 h, and collect the product after cooling.

[0123] (4) Washing, centrifuging, drying and vacuum activating the reaction product obtained in step (3) to obtain a UiO-66-CH3 metal organic framework material synthesized by a mixed ligand; wherein the drying temperature is 60-70°C for 18-24h; and the vacuum activation is performed at 120-180°C for 10-13h.

[0124] (5) The UiO-66-CH3 metal organic material obtained in step (4) is applied to the adsorption and removal of histamine in the solution.

[0125] (6) Weigh a certain amount of the UiO-66-CH3 adsorbent prepared in Example 2 into a 30 mL brown glass bottle, add 20 mL of a certain concentration and a certain pH of histamine solution to the brown glass bottle using a 10 mL pipette, place it on a constant temperature shaker, shake and mix for a certain time at a certain temperature and a speed of 200 r / min, take out the glass bottle, extract 10 mL of the supernatant with a 10 mL syringe without a needle, and filter it with a 0.22 μm filter membrane installed on the syringe. Referring to the national standard GB 5009.208-2016, the concentration of histamine was determined at 480 nm using Shimadzu UV-1900i, and the experimental results were averaged from three groups of data.

[0126] Characterization and analysis of adsorption performance of UiO-66-CH3 in Example 3

[0127] (1) The surface morphology of UiO-66-CH3 adsorbent was analyzed using a new thermal field emission scanning electron microscope (SEM, SU5000, Hitachi Instruments Co., Ltd., Japan). The results are shown in Figure 2 c;

[0128] Depend on Figure 2 c It can be seen that UiO-66-CH3 is a spherical particle with a particle size distribution of 150nm.

[0129] (2) The elemental composition of the adsorbent UiO-66-CH3 (EDS, Aztec, Hitachi Instruments Co., Ltd., Japan) was analyzed by energy dispersive X-ray spectrometry. The results are shown in Figure 3 g;

[0130] Depend on Figure 3 g It can be seen that UiO-66-CH3 contains elements such as C, O, and Zr, which proves the successful synthesis of the adsorbent.

[0131] (3) N2 adsorption-desorption curve (BET, Quantachorme Quadrasorb SI, Quantachrome Instruments, USA) was used to analyze the pore volume and surface area of ​​the samples. The results are shown in Figure 5 c;

[0132] The N2 adsorption-desorption isotherm of UiO-66-CH3 has no obvious hysteresis loop and shows a typical type I isotherm, indicating that UiO-66-CH3 has a microporous structure.

[0133] (4) The surface functional groups of the obtained product samples were tested using Fourier transform infrared spectrometer (FTIR, Thermo Nicolet iS, Thermo Fisher Scientific, USA). The results are shown in Figure 3 d;

[0134] Depend on Figure 3 d, 1380cm -1The peak at is the stretching of the CH3 group on the benzene ring, indicating the presence of CH3 groups in the UiO-66-CH3 adsorbent, proving the successful coordination of 2-methylphthalic acid.

[0135] (5) X-ray photoelectron spectroscopy (XPS, ESCALAB250Xi, Thermo Fisher Scientific, Inc., USA) was used to analyze the elemental composition information of the sample surface. The results are shown in Figure 3 gi;

[0136] In the Zr 3d spectrum, the deconvolution of the peaks is 3 / 2 (185.35 eV) and Zr 3d 5 / 2 The X-ray diffraction patterns of the adsorbent were analyzed by X-ray diffraction (XPS) spectra. ...

[0137] (6) The adsorption performance of UiO-66-CH3 metal framework material was studied by analyzing the kinetic data using pseudo-first-order kinetics and pseudo-second-order kinetics models. Figure 5 c;

[0138] Depend on Figure 5 c shows that the correlation coefficient of the pseudo-second-order kinetic model is slightly lower than that of the pseudo-first-order kinetic model. As shown in Table 1, the adsorption amount (93.721 mg / g) calculated by pseudo-first-order kinetics is close to the experimental value (87.747 mg / g), so the adsorption behavior is mainly physical adsorption.

[0139] (7) The adsorption interaction and surface distribution of histamine between UiO-66-CH3 metal organic framework material and histamine were analyzed by fitting the Langmuir and Freundlich isotherm adsorption models. The results are shown in Figure 5 f;

[0140] Depend on Figure 5 f, the correlation coefficients of the Langmuir model are higher than those of the Freundlich model, indicating that the Langmuir model is more suitable for the adsorption process of histamine by UiO-66-CH3, indicating that the adsorption process is a single-layer adsorption. As shown in Table 3, the maximum adsorption capacity obtained by the Langmuir model fitting at 278.15K is closer to the adsorption capacity obtained by the experiment.

[0141] (8) The potential of UiO-66-CH3 in practical applications was evaluated by testing its zeta potential, anti-interference property, and recyclability before and after adsorption, as well as its application in real salmon samples. The results are shown in Figure 6 ;

[0142] The Zeta potential of UiO-66-CH3 adsorbing histamine increased to varying degrees. The anti-interference performance of the composite material in the presence of competing substances such as malondialdehyde, sodium nitrite, hypoxanthine and sodium sulfide was evaluated, and the results showed that its adsorption efficiency for histamine could still be maintained above 74%. This indicates that UiO-66-CH3 has a selective adsorption capacity for histamine in a complex system. After 5 cycles, the removal rate of UiO-66-CH3 remained at about 44%.

[0143] (9) Adsorption experiments were conducted using MB (positively charged, no hydrogen bond donor), RdB (positively charged, hydrogen bond donor), MO (negatively charged, no hydrogen bond donor), and ARS (negatively charged, hydrogen bond donor) to verify the universal adsorption capacity of the material. The results are shown in Figure 7 ;

[0144] like Figure 7 ad, the removal rates of UiO-66-CH3 for different dyes are: methyl orange (MO) 36.0%, alizarin red S (ARS) 73.0%, rhodamine B (RhB) 43.0%, and only 16.0% for methylene blue (MB) without hydrogen bond donor. These results show that UiO-66-CH3 also has the potential to remove various anionic and cationic dyes through hydrogen bonding. Comprehensive adsorption process of Examples 1-3, Figure 5 g shows that it can be divided into two stages: surface diffusion and micropore diffusion. Figure 5 h indicates that the process is spontaneous and endothermic. Further, Figure 6 The enhancement of the spot and the increase of the area in df show the effective adsorption of histamine by Examples 1-3. Table 1 shows the kinetic parameters of histamine adsorption by Examples 1-3

[0145]

[0146] Table 2 shows the linear fitting parameters of the interparticle diffusion model for histamine adsorption in Examples 1-3.

[0147]

[0148]

[0149] Table 3 shows the isothermal adsorption line fitting parameters of histamine adsorption in Examples 1-3.

[0150]

[0151] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A metal organic framework material containing hydrogen bond donors and acceptors, characterized in that: The metal organic framework material is synthesized from zirconium tetrachloride and TPA series ligands-pyromellitic acid by a solvent thermal method.

2. The method for preparing a metal organic framework material containing hydrogen bond donors and acceptors according to claim 1, characterized in that: The specific steps include: Step 1: Under the action of ultrasound, fully dissolve zirconium tetrachloride and pyromellitic acid; Step 2: Transfer the pyromellitic acid solution to a round-bottom flask, add acetic acid as a regulator to control the size of MOF crystals and defects in the crystals, and place on a preheated magnetic stirrer until stirred evenly; Step 3: Add the zirconium tetrachloride solution in step 1 dropwise into the solution in step 2, mix well, heat to react, and collect the product after cooling; Step 4: washing, centrifuging and drying the reaction product obtained in step 3; Step 5: Activate the UiO-66-2COOH metal organic framework material containing hydrogen bond donors and acceptors for subsequent adsorption applications.

3. The method for preparing a metal organic framework material containing hydrogen bond donors and acceptors according to claim 2, characterized in that: In the step 1, the molar ratio of the zirconium source to the organic ligand is 1:1.6; the masses of zirconium tetrachloride and pyromellitic acid are 23.3 mg and 43.2 mg respectively.

4. The method for preparing a metal organic framework material containing hydrogen bond donors and acceptors according to claim 2, characterized in that: In the step 1, the solvents of zirconium tetrachloride and pyromellitic acid are both DMF [N,N-dimethylformamide], and the volume of the solvent is 10 ml.

5. The method for preparing a metal organic framework material containing hydrogen bond donors and acceptors according to claim 2, characterized in that: In the step 2, the volume of the acetic acid regulator is 1 ml; the preheating temperature of the magnetic stirrer is 120° C., the rotation speed is 200 rpm, and the stirring time is 30 min.

6. The method for preparing a metal organic framework material containing hydrogen bond donors and acceptors according to claim 2, characterized in that: In step 3, the zirconium tetrachloride solution is added at a speed of about 20 μL / s, the magnetic stirrer is set at a constant temperature of 120° C., a rotation speed of 200 r / min, and a heat preservation time of 24 h.

7. The method for preparing a metal organic framework material containing hydrogen bond donors and acceptors according to claim 2, characterized in that: In step 4, the detergent is a 95% ethanol solution, the volume ratio of the 95% ethanol solution to the original solution for the first wash is 1:1, the volume of ethanol added for the second and third washes is 20 ml, the centrifugal speed is 12000 rpm, the centrifugal time is 20 min, the drying temperature is 70°C, and the drying time is 8 h; in step 5, the activation temperature is 120°C, and the activation time is 24 h.

8. A preparation method for the above-mentioned metal organic framework material containing hydrogen bond donors and acceptors for adsorbing histamine based on strong hydrogen bonding, characterized in that: The specific steps include: Step S1: mixing a series of adsorbents of different masses with a histamine solution in proportion to prepare a reaction system, adsorbing and shaking the mixture at 298K and 200rpm for 6 hours, filtering after sampling, and measuring the concentration of histamine to determine the solid-liquid ratio of the system corresponding to the optimal adsorption capacity; preparing a reaction system with a series of histamine solutions of different concentrations and an adsorbent solution, shaking the mixture at 298K and 200rpm for 6 hours, filtering after sampling, and measuring the concentration of histamine to determine the histamine concentration corresponding to the optimal adsorption capacity; preparing a reaction system with a series of histamine solutions of different pH values ​​and an adsorbent solution, shaking the mixture at 298K and 200rpm for 6 hours, filtering after sampling, and measuring the concentration of histamine to determine the pH of the histamine solution corresponding to the optimal adsorption capacity; Step S2: The adsorbent and the histamine solution are mixed in proportion to prepare a reaction system, samples are taken at different time points to determine the real-time adsorption capacity, and the maximum adsorption capacity is evaluated by fitting the pseudo-first-order kinetic and pseudo-second-order kinetic models through calculating the real-time adsorption capacity.

9. The method for preparing the above-mentioned metal organic framework material containing hydrogen bond donors and acceptors for adsorbing histamine based on strong hydrogen bonding according to claim 8, characterized in that: In step S1, the solid-liquid ratio system screening preparation method includes: adding 2, 4, 6, 8, 10 and 12 mg of adsorbent to the histamine solution for reaction, and the actual specific optimization operation is that the concentration of the histamine solution is 30 mg / L, the volume is 20 ml, and the solvent is water; the solid-liquid ratio of the adsorption system is 0.1, 0.2, 0.3, 0.4 and 0.5 g / L, respectively, and the solid-liquid ratio corresponding to the optimal adsorption capacity is 0.2 g / L. The concentration system screening preparation method includes: adding 5 mg of adsorbent to the histamine solution with a concentration of 30, 40, 50, 100, 150 and 200 mg / L for reaction, and the actual specific optimization operation is: the concentration of the histamine solution is 30 mg / L, the volume is 20 ml, and the solvent is water; the solid-liquid ratio of the adsorption system is 0.1, 0.2, 0.3, 0.4 and 0.5 g / L, respectively, and the solid-liquid ratio corresponding to the optimal adsorption capacity is 0.2 g / L. The optimization operation is that the concentration of the histamine stock solution is 1 mg / mL, the volume is 20 ml, and the solvent is water; the histamine solutions of different concentrations are obtained by diluting the histamine stock solution of 1 mg / mL with ultrapure water, and the histamine concentration corresponding to the obtained optimal adsorption capacity is 30 mg / L, and the pH system screening preparation method includes: adding 5 mg of adsorbent to histamine solutions of pH 2, 4, 6, 8, 10 and 12 respectively for reaction, and the actual specific optimization operation is to adjust the pH value by using HCl and NaOH without significantly changing the overall concentration of the solution, and prepare a 20 mL reaction system, and the pH value of the histamine solution corresponding to the optimal adsorption capacity is 7; In the step S2, the method for preparing the reaction system comprises: adding 5 mg of adsorbent to the system prepared in the preferred embodiment of step S1 for reaction, and the actual specific optimization operation is, after adding 5 mg of adsorbent and 20 mL of histamine solution in sequence, using NaOH and HCl to adjust the pH of the system to 7; then adsorbing and oscillating at 298K and 200 rpm for 6 hours, sampling and recording the real-time concentration of histamine in the system, the selected time points are 0, 30, 60, 90, 120, 150, 180, 210, 240, 300, 360, 420, 480, 540, 600 min, the histamine concentration is 30 mg / L, and the solvent is water; In the step S1 and the step S2, the dilution and dispersion are carried out by ultrasonic treatment to ensure that the adsorbent is evenly distributed in the solution. Subsequently, after oscillating and adsorbing at 25° C. for 6 hours, a sample is taken for determination. After the sample is filtered, it is used for subsequent analysis. The actual specific optimization operation is to filter the solution using a 0.45 μm PES filter, retain 2 mL of the sample, and find the real-time concentration by comparing the standard curve of histamine concentration and absorbance. 0, 0.2, 0.4, 0.6, 0.8, 1.0 mL of histamine standard solution (equivalent to 0, 4.0, 8.0, 12, 16, 20 μg of histamine) and 2 mL of the sample extract are respectively taken into a 10 mL colorimetric tube, water is added to 1 mL, and then 1 mL of hydrochloric acid solution is added, mixed, 3 mL of sodium carbonate solution and 3 mL of azo reagent are added, water is added to the scale, mixed, and left for 10 minutes. The solution in the "0" tube is transferred to 1 cm cuvette, the wavelength of the spectrophotometer is adjusted to 480 nm, and after adjusting the absorbance to "0", the absorbance of a series of standard solutions and sample solutions is tested in turn, and a standard curve is drawn with absorbance A as the vertical axis and the mass of histamine as the horizontal axis. The concentration of the sodium carbonate solution is 50 g / L, and the solvent is water; the concentration of the A solution of the azo reagent (p-nitroaniline) is 2.5 g / L, and the solvent is water; the concentration of the B solution of the azo reagent (sodium nitrite solution) is 5 g / L, and the solvent is water; histamine solutions of different concentrations are obtained by diluting a histamine stock solution with a concentration of 1 mg / mL with ultrapure water.

10. Use of an adsorbent obtained by the method for preparing a metal organic framework material containing hydrogen bond donors and acceptors as claimed in claim 2 in removing histamine, a corruption product in aquatic products.

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