A quaternary ammonium modified chitosan-based zinc-iron hydrotalcite adsorption material, a preparation method and application thereof

Abstract

This invention provides a quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material, its preparation method, and its application, belonging to the field of adsorbent material technology. The preparation method provided by this invention includes the following steps: (1) mixing a mixed solution of iron and zinc salts with a quaternized modified chitosan solution to obtain a mixed solution; (2) adding a mixed solution of NaOH and Na2CO3 to the mixed solution obtained in step (1) for precipitation reaction followed by aging to obtain the quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material. The adsorbent material obtained by this invention has an adsorption capacity of 292.30 mg / g for amaranth, 288.17 mg / g for Acid Red, and 292.84 mg / g for Allura Red; after five cycles of use, the adsorption capacity for amaranth, Acid Red, and Allura Red can all reach more than 80% of the initial adsorption capacity, demonstrating good adsorption performance and reusability.

Description

Technical Field

[0001] This invention relates to the field of adsorption materials technology, and in particular to a quaternized ammonium-modified chitosan-based zinc-iron hydrotalcite adsorption material, its preparation method, and its application. Background Technology

[0002] The rapid expansion of the textile industry has led to the discharge of dyeing and printing wastewater into aquatic ecosystems. During discharge and degradation, dyes react with other elements in the environment, producing various harmful and hazardous compounds that negatively impact ecosystems. These compounds not only have harmful effects on organisms within the ecosystem but also exhibit teratogenic and neurotoxic effects on humans who ingest contaminated agricultural and fishery products.

[0003] For dye removal, adsorption is generally employed. Chitosan, a natural polysaccharide, possesses numerous active adsorption sites, making it a promising adsorbent material. However, its use is severely limited due to drawbacks such as difficulty in separation, low adsorption capacity, and easy dissolution and loss, hindering its application in water treatment. Hydrotalcite, with its unique interlayer anion exchange capacity and structural memory effect, can exchange numerous anionic pollutants in the aquatic environment with interlayer anions, thus removing pollutants from the water. Hydrotalcite also exhibits high mechanical strength and good stability. Therefore, modifying chitosan with hydrotalcite to obtain composite materials can improve the adsorption performance and stability of adsorbent materials. However, existing chitosan-based hydrotalcite adsorbent materials suffer from insufficient adsorption capacity of chitosan for hydrotalcite, resulting in insufficient adsorption performance and reusability of the composite adsorbent materials, requiring further improvement. Summary of the Invention

[0004] The purpose of this invention is to provide a quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material, its preparation method, and its applications. The quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material obtained by the preparation method provided by this invention can improve the adsorption performance and reusability of composite adsorbent materials.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0006] This invention provides a method for preparing a quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material, comprising the following steps:

[0007] (1) Mix the mixed solution of iron salt and zinc salt with the quaternized modified chitosan solution to obtain a mixed solution;

[0008] (2) Add the mixed solution of NaOH and Na2CO3 to the mixed solution obtained in step (1) for precipitation reaction and then age to obtain quaternized modified chitosan-based zinc iron hydrotalcite adsorbent material.

[0009] Preferably, in step (1), the molar ratio of iron salt to zinc salt in the mixed solution of iron salt and zinc salt is 1:(2-4).

[0010] Preferably, the molar ratio of iron salt in the mixed solution of iron salt and zinc salt in step (1) to quaternized modified chitosan in the quaternized modified chitosan solution is (9-11):1.

[0011] Preferably, in step (2), the molar ratio of NaOH to Na2CO3 in the mixed solution of NaOH and Na2CO3 is 1:(1.5 to 2.5).

[0012] Preferably, the rate at which the mixed solution of NaOH and Na2CO3 is added in step (2) is 3 to 7 mL / min.

[0013] Preferably, the precipitation reaction temperature in step (2) is 60-70°C and the precipitation reaction time is 0.5-1h.

[0014] Preferably, the pH value of the precipitation reaction in step (2) is 8 to 11.

[0015] Preferably, the aging temperature in step (2) is 40-80°C and the aging time is 20-24 hours.

[0016] The present invention also provides a quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material prepared by the preparation method described above, comprising quaternized modified chitosan and zinc-iron hydrotalcite adsorbed on the quaternized modified chitosan.

[0017] The present invention also provides the application of the quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material described in the above technical solution in the treatment of dyeing and printing wastewater.

[0018] This invention provides a method for preparing a quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material, comprising the following steps: (1) mixing a mixed solution of iron salt and zinc salt with a quaternized modified chitosan solution to obtain a mixed solution; (2) adding a mixed solution of NaOH and Na2CO3 to the mixed solution obtained in step (1) for precipitation reaction and aging to obtain a quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material. This invention uses quaternized modified chitosan to increase the number of ammonium groups on the chitosan structural units, thereby increasing the active adsorption sites of chitosan. After blending with hydrotalcite, the number of hydrotalcite groups on the chitosan surface is increased, thus improving the adsorption performance of the composite adsorbent material. By using a co-precipitation method to crystallize zinc-iron hydrotalcite on quaternized modified chitosan, the adsorption performance of the composite adsorbent material is further improved. The memory effect of hydrotalcite allows for the exchange of interlayer anions adsorbed by hydrotalcite through anion displacement effect, thereby improving reusability. The results of the examples show that the quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material prepared by the method of the present invention has an adsorption capacity of 292.30 mg / g for amaranth, 288.17 mg / g for acid red, and 292.84 mg / g for allura red. After five cycles of use, the adsorption capacity for amaranth, acid red, and allura red can still reach more than 80% of the initial adsorption capacity, indicating good adsorption performance and reusability. Attached Figure Description

[0019] Figure 1 This is a process flow diagram for preparing the quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material of the present invention.

[0020] Figure 2 SEM images of the quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material prepared in Example 1 of this invention; wherein, the magnification of a is 10W, the magnification of b is 5W, the magnification of c is 3W, and the magnification of d is 1W.

[0021] Figure 3 The image shows the XRD pattern of the quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material prepared in Example 1 of this invention.

[0022] Figure 4 SEM images of the chitosan-based zinc-iron hydrotalcite adsorbent material prepared in Comparative Example 1 of this invention are shown below; where a is magnified by 10W, b by 10, c by 3W, and d by 3W.

[0023] Figure 5 The image shows the XRD pattern of the chitosan-based zinc-iron hydrotalcite adsorbent material prepared in Comparative Example 1 of this invention. Detailed Implementation

[0024] This invention provides a method for preparing a quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material, comprising the following steps:

[0025] (1) Mix the mixed solution of iron salt and zinc salt with the quaternized modified chitosan solution to obtain a mixed solution;

[0026] (2) Add the mixed solution of NaOH and Na2CO3 to the mixed solution obtained in step (1) for precipitation reaction and then age to obtain quaternized modified chitosan-based zinc iron hydrotalcite adsorbent material.

[0027] This invention involves mixing a mixed solution of iron salt and zinc salt with a quaternized modified chitosan solution to obtain a mixed solution.

[0028] In this invention, the iron salt in the mixed solution of iron and zinc salts is preferably FeCl3. Limiting the iron salt to the aforementioned type allows for sufficient complexation between iron ions and the active adsorption sites of ammonium groups on the quaternized chitosan. The ionic radius of the iron ions is close to the ionic radius required to form the hydrotalcite structure, and excess chloride ions are easily replaced by hydroxyl groups, thereby promoting the formation of the hydrotalcite structure on the surface of the quaternized chitosan.

[0029] In this invention, the zinc salt in the mixed solution of iron and zinc salts is preferably ZnCl2. Limiting the zinc salt to the aforementioned types allows zinc ions and iron ions with similar radii to form highly crystalline hydrotalcite on the surface of quaternized chitosan. Furthermore, excess chloride ions are easily replaced by hydroxyl groups, thereby promoting the formation of hydrotalcite structures on the surface of quaternized chitosan. This results in a material that possesses the memory effect of hydrotalcite while being less prone to dispersion, exhibiting a more stable structure and easier recycling.

[0030] In this invention, the molar ratio of iron salt to zinc salt in the mixed solution of iron salt and zinc salt is preferably 1:(2-4), more preferably 1:(2.5-3). This invention limits the molar ratio of iron salt to zinc salt in the mixed solution of iron salt and zinc salt to the above range to obtain zinc-iron hydrotalcite with good crystal structure. If the ratio of iron salt to zinc salt is not within this range, the crystal structure of the hydrotalcite will change to that of iron-zinc oxide, and the synthesized oxide will not have the memory effect of hydrotalcite.

[0031] The present invention does not have a special limitation on the concentration of the mixed solution of iron salt and zinc salt, as long as it can completely dissolve the iron salt and zinc salt.

[0032] In this invention, the preferred molar ratio of iron salt in the mixed solution of iron salt and zinc salt to quaternized modified chitosan in the quaternized modified chitosan solution is (9-11):1, more preferably 10:1. Limiting the molar ratio of iron salt in the mixed solution of iron salt and zinc salt to quaternized modified chitosan in the quaternized modified chitosan solution to the above range improves the adsorption performance and reusability of the composite adsorbent material.

[0033] In this invention, the quaternized modified chitosan solution is preferably obtained by mixing quaternized modified chitosan and an aqueous acetic acid solution; the mass concentration of the aqueous acetic acid solution is preferably 5-10%, more preferably 5-8%. Using the above-mentioned mass concentration of aqueous acetic acid solution in this invention can better achieve the dissolution of quaternized modified chitosan.

[0034] The present invention does not have a special limitation on the amount of acetic acid added to the quaternized modified chitosan solution, as long as it can completely dissolve the quaternized modified chitosan.

[0035] The present invention does not have any special limitations on the mixing operation; it is sufficient to mix the mixed solution of iron salt and zinc salt with the quaternized modified chitosan solution thoroughly.

[0036] After obtaining the mixture, the present invention adds a mixed solution of NaOH and Na2CO3 to the mixture to carry out a precipitation reaction and then ages it to obtain a quaternized modified chitosan-based zinc iron hydrotalcite adsorbent material.

[0037] In this invention, the molar ratio of NaOH to Na2CO3 in the mixed solution of NaOH and Na2CO3 is preferably 1:(1.5-2.5), more preferably 1:2. This invention uses the mixed solution of NaOH and Na2CO3 as a precipitant to react with Fe in the mixture. 3+ With Zn 2+ A precipitation reaction occurs to form zinc-iron hydrotalcite. This invention limits the molar ratio of NaOH to Na2CO3 in the mixed solution of NaOH and Na2CO3 to the above-mentioned range. This ensures that during the formation of zinc-iron hydrotalcite, the interlayer anions are mostly carbonate ions. During heating and drying, the carbonate ions are removed as water molecules and carbon dioxide, improving the adsorption performance and reusability of the composite adsorbent material. This invention does not have a specific limitation on the concentration of the mixed solution containing NaOH and Na2CO3; concentrations commonly used by those skilled in the art can be used.

[0038] In this invention, the addition rate of the mixed solution of NaOH and Na2CO3 is preferably 3–7 mL / min, more preferably 4–6 mL / min. Limiting the addition rate to the above range ensures a complete reaction and results in the formation of zinc-iron hydrotalcite with a good crystal structure.

[0039] In this invention, the pH value of the precipitation reaction is preferably 8 to 11, more preferably 10 to 11. Limiting the pH value of the precipitation reaction to this range avoids both excessively low pH levels leading to co-precipitation with lower crystal forms and excessively high pH levels causing dissolution of ZnOH2.

[0040] The present invention does not have a special limitation on the amount of the mixed solution of NaOH and Na2CO3 added, as long as the pH value of the precipitation reaction is in the range of 8 to 11.

[0041] In this invention, the temperature of the precipitation reaction is preferably 60–70°C, more preferably 65°C; the time of the precipitation reaction is preferably 0.5–1 h. By limiting the temperature and time of the precipitation reaction to the above ranges, this invention can enable Fe… 3+ and Zn 2+ It undergoes a precipitation reaction with a mixed solution of NaOH and Na2CO3 to form zinc-iron hydrotalcite, which is fully precipitated on the quaternized modified chitosan.

[0042] In this invention, the precipitation reaction is preferably carried out under stirring conditions. The method of stirring is not particularly limited in this invention; any stirring method commonly used by those skilled in the art can be employed.

[0043] In this invention, the aging process is preferably carried out under static conditions; the aging temperature is preferably 40–80°C, more preferably 65°C; and the aging time is preferably 20–24 hours, more preferably 21–23 hours. This invention promotes further crystallization of the hydrotalcite generated by the precipitation reaction through aging. Limiting the aging temperature and time to the above-mentioned ranges ensures sufficient crystallization of the zinc-iron hydrotalcite, which is beneficial to the adsorption performance and reusability of the composite adsorbent material.

[0044] After aging, the present invention preferably performs sequential filtration, washing, drying and grinding on the aged product to obtain quaternized modified chitosan-based zinc iron hydrotalcite adsorbent material.

[0045] The present invention does not impose any special limitations on the apparatus and operation of the vacuum filtration; any vacuum filtration apparatus and operation known to those skilled in the art can be used.

[0046] The present invention does not have any particular limitation on the solvent used for washing. The product obtained after vacuum filtration can be washed to neutral by a washing solvent commonly used by those skilled in the art.

[0047] In this invention, the drying is preferably carried out in an oven; the drying temperature is preferably 60–70°C; and the drying time is preferably >20 hours. This invention does not specify a particular type of oven; any oven commonly used by those skilled in the art can be used. Limiting the drying temperature and time to the above-mentioned ranges in this invention effectively removes moisture from the product.

[0048] The present invention does not have special requirements for the equipment and operation used for grinding, as long as the particle size of the quaternized modified chitosan-based zinc iron hydrotalcite adsorbent material obtained after grinding is less than 106 μm.

[0049] This invention improves the adsorption performance of the composite adsorbent material by using quaternized chitosan to increase the number of ammonium groups on the chitosan structural units, thereby increasing the number of active adsorption sites on the chitosan. After blending with hydrotalcite, the number of hydrotalcite on the chitosan surface is increased. Furthermore, the adsorption performance and reusability of the composite adsorbent material are further improved by using a co-precipitation method to crystallize zinc-iron hydrotalcite on the quaternized chitosan.

[0050] The present invention also provides a quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material prepared by the preparation method described above, comprising quaternized modified chitosan and zinc-iron hydrotalcite adsorbed on the quaternized modified chitosan.

[0051] The present invention also provides the application of the quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material described in the above technical solution in the treatment of dyeing and printing wastewater.

[0052] In this invention, the preferred mass ratio of the quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent to the adsorbate in the dyeing and printing wastewater is (2.4-4):1, more preferably 3.2:1. Limiting the mass ratio of the quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent to the adsorbate in the dyeing and printing wastewater to the above range allows for better adsorption of the adsorbate in the wastewater, thereby improving the removal rate of the adsorbate.

[0053] In embodiments of the present invention, such as Figure 1 As shown, the preparation process of the quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material is as follows:

[0054] FeCl3, ZnCl2, and quaternized modified chitosan (O-HTCC) were mixed to obtain O-HTCC-Fe 3+The precursor solution (mixture) is then added dropwise with a mixed solution of NaOH and Na2CO3 to maintain the pH of the mixture at 8-11. Precipitation reaction is carried out under stirring. After the precipitation reaction is completed, the mixture is aged for 20 hours to obtain O-HTCC-ZnFe-LDH solution. The solution is washed with deionized water until neutral to obtain O-HTCC-ZnFe-LDH sample. After drying and grinding, O-HTCC-ZnFe-LDH powder (quaternized ammonium modified chitosan-based zinc iron hydrotalcite adsorbent material) is obtained.

[0055] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0056] Example 1

[0057] A method for preparing a quaternized ammonium-modified chitosan-based zinc-iron hydrotalcite adsorbent material comprises the following steps:

[0058] (1) A mixed solution of FeCl3 and ZnCl2 is mixed with a quaternized chitosan solution to obtain a mixed solution; the molar ratio of FeCl3 to ZnCl2 in the mixed solution of FeCl3 and ZnCl2 is 1:3; the molar ratio of FeCl3 in the mixed solution of FeCl3 and ZnCl2 to the quaternized chitosan in the quaternized chitosan solution is 10:1; the quaternized chitosan solution is obtained by mixing quaternized chitosan and a 5% (w / w) aqueous solution of acetic acid;

[0059] (2) A mixed solution containing NaOH and Na2CO3 is added to the mixed solution obtained in step (1) at a rate of 5 mL / min. After precipitation reaction at 70°C for 1 h, the mixture is aged at 65°C for 20 h. Then, the mixture is filtered and washed until neutral. The filter cake is dried in an oven at 60°C for 24 h and ground through a 150-mesh sieve to obtain quaternized ammonium modified chitosan-based zinc iron hydrotalcite adsorbent material (denoted as O-HTCC@ZnFe-LDH). The molar ratio of NaOH to Na2CO3 in the mixed solution containing NaOH and Na2CO3 is 1:2. The pH value of the mixed solution after the addition is 10-11.

[0060] The scanning electron microscope (SEM) image of the quaternized ammonium-modified chitosan-based zinc iron hydrotalcite adsorbent material prepared in this embodiment is shown below. Figure 2As shown, the magnification of a is 10W, the magnification of b is 5W, the magnification of c is 3W, and the magnification of d is 1W. From a, it can be seen that there is an interlaced lamellar structure with a wide gap on the O-HTCC@ZnFe-LDH surface; from c and d, a distinct layered superposition structure with an uneven surface can be seen, indicating that ZnFe-LDH was successfully loaded onto the O-HTCC surface.

[0061] The X-ray diffraction (XRD) pattern of the quaternized ammonium-modified chitosan-based zinc iron hydrotalcite adsorbent material prepared in this embodiment is shown below. Figure 3 As shown, from Figure 3 As can be seen from the XRD, sharp symmetrical diffraction peaks are present, indicating that the synthesized O-HTCC@ZnFe-LDH has good crystallinity. Simultaneously, O-HTCC@ZnFe-LDH also exhibits relatively obvious hydrotalcite diffraction peaks, emitting at positions of 12.91°, 28.09°, 34.31°, and 59.87°, corresponding to (003), (006), (009), and (110), respectively, confirming the presence of a bimetallic hydroxide layered structure in the adsorbent material. This indicates that hydrotalcite was successfully grown on the O-HTCC surface, and O-HTCC@ZnFe-LDH was successfully synthesized.

[0062] Comparative Example 1

[0063] The only difference between Comparative Example 1 and Example 1 is that the quaternized modified chitosan solution was replaced with a chitosan solution. Otherwise, they were the same as in Example 1, and chitosan-based zinc-iron hydrotalcite adsorbent material (denoted as CS@ZnFe-LDH) was obtained.

[0064] The scanning electron microscope (SEM) image of the chitosan-based zinc-iron hydrotalcite adsorbent material prepared in Comparative Example 1 is shown below. Figure 4 As shown, the magnification of a is 100,000 times, the magnification of b is 10 times, the magnification of c is 30,000 times, and the magnification of d is 30,000 times. Figure 4 It can be seen that CS@ZnFe-LDH has a distinct sheet-like structure with an uneven surface and interwoven layered structures. Some of the layered structures are smooth and flat, which indicates that chitosan has been successfully cross-linked with ZnFe-LDH as its backbone.

[0065] The X-ray diffraction (XRD) pattern of the chitosan-based zinc-iron hydrotalcite adsorbent material prepared in Comparative Example 1 is shown below. Figure 5 As shown, from Figure 5As can be seen, sharp and symmetrical diffraction peaks appeared in the XRD, indicating that the synthesized CS@ZnFe-LDH has good crystallinity. At the same time, CS@ZnFe-LDH also showed relatively obvious diffraction peaks unique to hydrotalcite, namely peaks at 12.91°, 28.09°, 34.31°, and 59.87°, corresponding to (003), (006), (009), and (110), respectively, confirming that the adsorbent material has a layered structure of bimetallic hydroxide, indicating the successful synthesis of CS@ZnFe-LDH.

[0066] Test case

[0067] The 3.2 mg of quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material prepared in Example 1 was placed in 40 ml of aqueous solutions of amaranth, acid red, or allura red, and the transmittance of ultraviolet light before and after adsorption was measured to calculate the concentration of the dye before and after adsorption. The mass ratio of the quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material to the aqueous solutions of amaranth, acid red, or allura red was 3.2:1.

[0068] After the first adsorption is completed, the quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material is recovered by centrifugation and sieving, and then subjected to a second adsorption. This process is repeated five times.

[0069] The dye removal rate is calculated as shown in Equation 1, and the adsorption capacity of the quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material is calculated as shown in Equation 2.

[0070]

[0071] In the formula: η is the removal rate, in %;

[0072] Qe is the amount of adsorption at adsorption equilibrium, expressed in mg / g.

[0073] C0 represents the initial ion concentration in the solution before adsorption, expressed in mg / L.

[0074] Ce represents the concentration of remaining ions in the solution at adsorption equilibrium, expressed in mg / L.

[0075] V is the volume of the solution, in L;

[0076] m represents the amount of adsorbent added, in mg.

[0077] The adsorption results of the quaternized modified chitosan-based zinc-iron hydrotalcite adsorbent material prepared in Example 1 are shown in Table 1.

[0078] Table 1. Adsorption results of the quaternized ammonium-modified chitosan-based zinc-iron hydrotalcite adsorbent material prepared in Example 1.

[0079] O-HTCC@ZnFe-LDH Amaranth red mg / g Acid Red mg / g Temptation Red mg / g first 292.30 288.17 292.84 The second 277.69 273.76 278.20 The third 263.80 260.07 264.29 Fourth 250.61 247.07 251.07 Fifth 238.08 234.72 238.52

[0080] The adsorption results of the chitosan-based zinc-iron hydrotalcite adsorbent material prepared in Comparative Example 1 are shown in Table 2.

[0081] Table 2 shows the adsorption results of the chitosan-based zinc-iron hydrotalcite adsorbent material prepared in Comparative Example 1.

[0082] CS@ZnFe-LDH Amaranth red mg / g Acid Red mg / g Temptation Red mg / g first 191.93 219.29 150.32 The second 182.34 195.63 141.64 The third 171.97 186.38 131.84 Fourth 163.49 173.12 124.87 Fifth 157.32 162.61 120.88

[0083] As shown in Tables 1 and 2, the quaternized ammonium-modified chitosan-based zinc-iron hydrotalcite adsorbent material has an adsorption capacity of 292.30 mg / g for amaranth, 288.17 mg / g for acid red, and 292.84 mg / g for allura red, which is higher than that of chitosan-based zinc-iron hydrotalcite. After five cycles of use, the adsorption capacity for amaranth, acid red, and allura red can all reach more than 80% of the initial adsorption capacity, demonstrating good adsorption performance and reusability.

[0084] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a quaternary ammonium modified chitosan-based zinc-iron hydrotalcite adsorption material, comprising the following steps: (1) mixing a mixed solution of iron salt and zinc salt with a quaternary ammonium modified chitosan solution to obtain a mixed solution; (2) adding a mixed solution of NaOH and Na2CO3 to the mixed solution obtained in step (1) to perform a precipitation reaction and then aging to obtain a quaternary ammonium modified chitosan-based zinc-iron hydrotalcite adsorption material; in the mixed solution of iron salt and zinc salt in step (1), the molar ratio of iron salt to zinc salt is 1: (2-4) ; in step (2), the precipitation reaction is performed at a temperature of 60-70℃ for 0.5-1h; in step (2), the pH value of the precipitation reaction is 8-11.

2. The production method according to claim 1, characterized by, in the mixed solution of iron salt and zinc salt in step (1), the molar ratio of iron salt to quaternary ammonium modified chitosan in the quaternary ammonium modified chitosan solution is (9-11) :

1.

3. The preparation method according to claim 1, characterized in that, in the mixed solution of NaOH and Na2CO3 in step (2), the molar ratio of NaOH to Na2CO3 is 1: (1.5-2.5).

4. The production method according to claim 1 or 3, characterized by, in step (2), the mixed solution of NaOH and Na2CO3 is added at a speed of 3-7mL / min.

5. The preparation method according to claim 1, characterized in that, in step (2), the aging is performed at a temperature of 40-80℃ for 20-24h. 6.The quaternary ammonium modified chitosan-based zinc-iron hydrotalcite adsorption material prepared by the method of any one of claims 1-5, comprising quaternary ammonium modified chitosan and zinc-iron hydrotalcite adsorbed on the quaternary ammonium modified chitosan. 7.The application of the quaternary ammonium modified chitosan-based zinc-iron hydrotalcite adsorption material of claim 6 in the treatment of printing and dyeing wastewater.

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