Sludge heavy metal resource recycling material and preparation method thereof

Abstract

The application discloses a sludge heavy metal resource recovery material and a preparation method thereof in the technical field of heavy metal recovery, and the microcrystalline cellulose is used as a base material, mainly a straight-chain polysaccharide material combined by beta-1, 4-glucoside bonds, and the material has degradability, is green and pollution-free, and the modification of the microcrystalline cellulose increases active groups of S elements and N elements, improves the combination capacity of heavy metal ions, and enhances the adsorption performance.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of heavy metal recovery, and particularly relates to a sludge heavy metal resource recovery material and a preparation method thereof. BACKGROUND

[0002] Industrial sludge has a wide source, mainly including papermaking sludge, electroplating sludge, textile printing and dyeing, tanning, smelting and metallurgy industries, and has a complex composition. The papermaking sludge is mainly composed of inorganic components, including lignin, chlorine-containing wastewater and sulfur-containing wastewater. The components in the electroplating sludge are usually related to the electroplating process, and a large amount of heavy metals such as cadmium, chromium, nickel, copper, manganese and mercury exist in the form of soluble salts. In the tanning industry, a large amount of chemical reagents are used, for example, the use of chromium tanning agents causes a large amount of residual trivalent chromium salt. In the smelting and metallurgy industry, the generated sludge is mainly metal ore waste, such as metal oxides such as iron oxide, aluminum oxide and zinc oxide, and heavy metals such as lead, cadmium, nickel and copper generated in the smelting process, which exist in the form of soluble salts in the sludge. In the prior art, the main treatment methods for heavy metal sludge include landfill fixation, heavy metal ions are easy to migrate, and usually have great hidden dangers to the soil environment and groundwater environment. Through the heat treatment methods of incineration, pyrolysis and melting, the heavy metals can be concentrated in the ash, which is beneficial to further resource utilization, but the energy consumption is high during the treatment process, and a flue gas purification device needs to be matched, which increases the cost and is easy to cause secondary pollution. Through chemical reagent precipitation treatment, the heavy metals form insoluble precipitates for separation, but the cost of the reagent is high, the chemical sludge after treatment still needs further treatment, the treatment effect is unstable, and the reaction conditions have a great influence. The biological treatment method is the most environmentally friendly method, but the treatment period is too long and the efficiency is relatively low. SUMMARY

[0003] In view of the above problems, the sludge heavy metal resource recovery material and the preparation method thereof are provided to overcome the defects of the prior art. The microcrystalline cellulose is used as the base material, which is mainly a straight-chain polysaccharide substance combined by beta-1, 4-glucoside bonds. The microcrystalline cellulose has degradability, green and no pollution. The activity groups of S elements and N elements are increased by modifying the microcrystalline cellulose, so that the combination ability to heavy metal ions is improved, and the adsorption performance is enhanced.

[0004] In order to achieve the above purpose, the technical scheme adopted by the application is as follows:

[0005] The application also provides a preparation method of the sludge heavy metal resource recovery material, which specifically includes the following steps:

[0006] S1, dissolve thiourea in deionized water, add sulfuric acid solution, add neutral aluminum oxide, mix uniformly, then add epichlorohydrin, adjust the water bath temperature to 30-35 DEG C, stir at a speed of 150-180 rpm for 20-40 min, then extract the reaction mixture with a mixed solution of n-hexane and chloroform, collect the organic phase, remove the water, and distill under reduced pressure to obtain epichlorohydrin;

[0007] Preferably, in step S1, the mass concentration of thiourea in deionized water is 0.3-0.4 g / mL;

[0008] Preferably, in step S1, the mass fraction of the sulfuric acid solution is 5%, and the volume of the sulfuric acid solution added is 30-35% of the volume of the thiourea solution; the amount of neutral aluminum oxide added in the thiourea solution is 10-20 g / L;

[0009] Preferably, in step S1, the mass-volume ratio g / mL of thiourea to epichlorohydrin is 0.90-0.98 g / mL;

[0010] S2, place microcrystalline cellulose in deionized water, stir until completely dispersed, add sodium hydroxide solution, and ultrasonically treat at a power of 400 W for 50-60 min, then stir the solution to a uniform state to obtain a cellulose solution;

[0011] Preferably, in step S2, the mass fraction of the microcrystalline cellulose in deionized water is 5-8%;

[0012] Preferably, in step S2, the mass fraction of sodium hydroxide in the sodium hydroxide solution is 10-20%, and the volume of the sodium hydroxide solution added is 25-50% of the volume of the microcrystalline cellulose solution;

[0013] S3, dissolve dimethylamine and di-sec-butylamine in deionized water, add to the cellulose solution prepared in step S2, stir and mix uniformly, then add the epichlorohydrin prepared in step S1, increase the temperature to 65-75 DEG C, and stir at a speed of 200-220 rpm for 2-3 h, then dialyze in a dialysis bag with a molecular weight cutoff of 8000-14000 until the solution is neutral, and freeze-dry to obtain a sludge heavy metal resource recycling material;

[0014] Preferably, in step S3, the volume ratio between dimethylamine and di-sec-butylamine is 10:1.6-6;

[0015] Preferably, in step S3, the volume ratio between dimethylamine and epichlorohydrin is 0.8-1.2:1;

[0016] The application also provides a sludge heavy metal resource recycling material prepared according to the above method.

[0017] The present application has the following beneficial effects:

[0018] The present application provides a sludge heavy metal resource recycling material, which uses microcrystalline cellulose as a base material, mainly a linear polysaccharide substance combined by beta-1, 4-glucoside bonds, has degradability, is green and pollution-free, and has increased activity groups of S and N elements by modifying the microcrystalline cellulose, thereby improving the binding capacity for pollutants and enhancing the adsorption performance for heavy metals; the present application uses epichlorohydrin as a crosslinking agent to cause crosslinking of cellulose molecules, and at the same time, dimethylamine, di-sec-butylamine and epichlorohydrin undergo polymerization, so that the polyamine compound and the crosslinked cellulose form a complex three-dimensional network structure, thereby improving the stability of the cellulose and increasing the active sites of the recycling material for adsorbing pollutants; the epichlorohydrin can introduce S elements into the recycling material, and the sulfur element has a vacant electron orbital, which can form a coordination action with heavy metal ions, thereby adsorbing the heavy metal ions; after the heavy metal ions are recovered by removal treatment, the recycling material has good reusability and can be recycled multiple times, thereby reducing the cost of the heavy metal ion recovery industry. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 The sludge heavy metal resource recycling material prepared in Example 1 of the present application and microcrystalline cellulose infrared spectrum;

[0020] Figure 2 The SEM image of the sludge heavy metal resource recycling material described in Example 1 of the present application;

[0021] Figure 3 The adsorption performance results of the recycling materials prepared in Examples 1-3 and Comparative Examples 1-3 for cadmium ions;

[0022] Figure 4 The adsorption and regeneration performance results of the recycling materials prepared in Examples 1-3 and Comparative Examples 1-3.

[0023] The accompanying drawings are included to provide a further understanding of the present application, and constitute a part of the specification, illustrate the present application, and are used to explain the present application, and do not constitute a limitation on the present application. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application; based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Methods and materials similar or equivalent to those described herein can be used in the practice of the present application. The described preferred embodiments are intended to be illustrative only and are not intended to limit the scope of the application.

[0026] The experimental methods in the following examples are all conventional methods unless otherwise specified; the experimental materials used in the following examples are all purchased from commercial channels unless otherwise specified.

[0027] The sources of the materials used in the present application are shown as follows:

[0028] Dimethylamine (Cas NO: 124-40-3), brand Macklin, item number D807422, specification dimethylamine aqueous solution, 40 wt. % in H2O.

[0029] Microcrystalline cellulose (Cas No: 9004-34-6), brand Shanghai Reagent, purchased from Sinoreagent Co., Ltd., code 68005882.

[0030] Example 1

[0031] The present embodiment provides a preparation method of a sludge heavy metal resource recycling material, which specifically comprises the following steps:

[0032] S1, accurately take 40g of thiourea and place it in a beaker, add 100mL of deionized water and stir until the thiourea is completely dissolved, prepare a 5% sulfuric acid solution, take 30mL and add it to the thiourea solution, add 2g of neutral alumina, mix the solution uniformly on a 180rpm magnetic stirrer, add 36mL of epichlorohydrin, continue to stir under the condition of increasing the water bath temperature to 30℃ for 30min, then prepare an extractant by mixing n-hexane and chloroform according to the volume ratio of 2:1, which is used for extraction of the reactants, extract three times, collect the organic phase, remove the excess water in the organic phase with anhydrous sodium sulfate, and remove the organic solvent by reduced pressure distillation to obtain epichlorohydrin; in the present embodiment, 15.38g of epichlorohydrin is obtained, and the yield is 28.35%; the proton nuclear magnetic resonance spectrum of the product is: 1 HNMR (400MHz, CDCl3) δ 3.21 (d, 2H) 2.84-2.69 (m, 1H), 2.41 (dd, 1H), 2.18 (d, 1H);

[0033] S2, the microcrystalline cellulose is placed in a 35°C oven to dry to constant weight, accurately weigh 5g of dried microcrystalline cellulose into a beaker, add 100mL of deionized water to stir, fully disperse the microcrystalline cellulose in the deionized water, add 25mL of a 20% by mass sodium hydroxide solution, mix well, and then place in an ultrasonic machine for ultrasonic treatment at 400W power for 60min, continuously stirring the reaction system during ultrasonic treatment, until the solution is uniform, to obtain a cellulose solution;

[0034] S3, accurately measure 10mL of dimethylamine aqueous solution and 1.6mL of di-sec-butylamine into a flask, mix well, then add the cellulose solution prepared in step S2, continue to stir, take 10mL of the epichlorohydrin solution prepared in step S1, dissolve in 150mL of a 50% by volume ethanol aqueous solution to prepare an epichlorohydrin solution, add the epichlorohydrin solution to the reaction system at a rate of 10mL / min, after the epichlorohydrin solution is completely added, seal the reaction system, increase the temperature to 70°C under a nitrogen atmosphere, adjust the stirrer speed to 200rpm, and react for 3h, then place the reaction system in a 14000 molecular weight cut-off dialysis bag and dialyze with deionized water until the solution is neutral, then freeze-dry under the conditions of a temperature of -50°C and a vacuum degree of <100pa to obtain a sludge heavy metal resource recycling material;

[0035] Compare the infrared spectrum of the sludge heavy metal resource recycling material with that of microcrystalline cellulose, Figure 1 The infrared spectrum of the sludge heavy metal resource recycling material prepared in this example is as follows, Figure 1 Figure 1 is the infrared spectrum of microcrystalline cellulose, and Figure 2 is the sludge heavy metal resource recycling material prepared in this example, which has a relatively obvious characteristic peak at 3500-3300cm -1 , which is the characteristic peak of N-H and O-H bond, and also has a bending vibration peak of N-H at 1650-1620cm -1 , and a C-S characteristic peak at 1200-1170cm -1 , indicating that epichlorohydrin participated in the crosslinking reaction of cellulose and polyamine compounds;

[0036] This example also provides a sludge heavy metal resource recycling material prepared according to the above method.

[0037] Figure 2 The SEM image of the sludge heavy metal resource recycling material described in this example is as follows, first, the sample surface is brittle fractured with liquid nitrogen, then the sample surface is gold sprayed after thorough drying, and finally the sample surface morphology is observed using a JSM-6510 scanning electron microscope, and the recycling material has a complex multi-layer network structure.

[0038] Example 2

[0039] The present embodiment provides a preparation method of sludge heavy metal resource recycling material, which specifically comprises the following steps:

[0040] S1, accurately take thiourea 30 g and place it in a beaker, add 100 mL of deionized water and stir until the thiourea is completely dissolved, prepare a 5% sulfuric acid solution, take 35 mL and add it to the thiourea solution, add 1 g of neutral aluminum oxide, mix the solution evenly on a 180 rpm magnetic stirrer, add 28.52 mL of epichlorohydrin, continue to stir under the condition, increase the water bath temperature to 30℃, react for 40 min, then prepare an extractant by mixing n-hexane and chloroform according to the volume ratio of 2:1, which is used for extraction of the reactants, after extraction for three times, collect the organic phase, remove the excess water in the organic phase with anhydrous sodium sulfate, and remove the organic solvent by reduced pressure distillation to obtain epichlorohydrin; In this embodiment, 10.23 g of epichlorohydrin was obtained, with a yield of 25.96%;

[0041] S2, dry the microcrystalline cellulose in a 35℃ oven until the weight is constant, accurately take 8 g of dried microcrystalline cellulose and place it in a beaker, add 100 mL of deionized water and stir, completely disperse the microcrystalline cellulose in the deionized water, add 50 mL of 10% sodium hydroxide solution, mix evenly, and then place it in an ultrasonic machine for ultrasonic treatment at a power of 400W for 60 min, continuously stir the reaction system during ultrasonic treatment, and the solution reaches a uniform state to obtain a cellulose solution;

[0042] S3, accurately measure 10 mL of dimethylamine aqueous solution and 6 mL of di-sec-butylamine into a flask, mix evenly, then add the cellulose solution prepared in step S2, continue to stir, take 8 mL of epichlorohydrin prepared in step S1, dissolve it in 150 mL of 50% ethanol aqueous solution to prepare an epichlorohydrin solution, and add the epichlorohydrin solution to the reaction system at a speed of 10 mL / min, after the epichlorohydrin solution is added, seal the reaction system, increase the temperature to 75℃ under nitrogen atmosphere, adjust the stirrer speed to 200 rpm, react for 3 h, then place the reaction system in a 12000 molecular weight cut-off dialysis bag and dialyze with deionized water until the solution is neutral, then freeze-dry under the conditions of -50℃ temperature and <100 pa vacuum to obtain a sludge heavy metal resource recycling material;

[0043] The present embodiment also provides a sludge heavy metal resource recycling material prepared according to the above method.

[0044] Example 3

[0045] The present embodiment provides a preparation method of sludge heavy metal resource recycling material, which specifically comprises the following steps:

[0046] S1, accurately take thiourea 35 g into a beaker, add 100 mL of deionized water and stir until the thiourea is completely dissolved, prepare a 5% sulfuric acid solution, take 30 mL and add it to the thiourea solution, add 1.5 g of neutral alumina, mix the solution evenly on a 150 rpm magnetic stirrer, add 34.3 mL of epichlorohydrin, continue to stir under the condition, raise the water bath temperature to 35℃, react for 20 min, then prepare an extractant by mixing n-hexane and chloroform according to the volume ratio of 2:1, which is used for extraction of the reactants, after extraction for three times, collect the organic phase, remove the excess water in the organic phase with anhydrous sodium sulfate, and remove the organic solvent by reduced pressure distillation to obtain epichlorohydrin; in this example, the epichlorohydrin is 12.74 g, and the yield is 26.84%;

[0047] S2, dry the microcrystalline cellulose in a 35℃ oven until the weight is constant, accurately take 6.5 g of dried microcrystalline cellulose into a beaker, add 100 mL of deionized water and stir, completely disperse the microcrystalline cellulose in the deionized water, add 35 mL of 20% sodium hydroxide solution, mix evenly, and then place it in an ultrasonic machine for ultrasonic treatment at a power of 400W for 50 min, continuously stirring the reaction system during ultrasonic treatment, until the solution is uniform, to obtain a cellulose solution;

[0048] S3, accurately take 10 mL of dimethylamine aqueous solution and 3.6 mL of di-sec-butylamine into a flask, stir and mix evenly, then add 100 mL of the cellulose solution prepared in step S2, continue to stir, take 12 mL of the epichlorohydrin prepared in step S1, dissolve it in 150 mL of 50% ethanol aqueous solution to prepare an epichlorohydrin solution, add the epichlorohydrin solution to the reaction system at a speed of 10 mL / min, after the epichlorohydrin solution is added, seal the reaction system, raise the temperature to 65℃ under nitrogen atmosphere, adjust the stirrer speed to 220 rpm, react for 2 h, then place the reaction system in a 8000 molecular weight cut-off dialysis bag and dialyze with deionized water until the solution is neutral, then freeze-dry under the conditions of -50℃ temperature and <100 pa vacuum to obtain a sludge heavy metal resource recycling material;

[0049] The present example also provides a sludge heavy metal resource recycling material prepared according to the above method.

[0050] Comparative Example 1

[0051] This comparative example provides a heavy metal recycling material and a preparation method thereof, which is different from example 1 only in that the preparation method of the heavy metal recycling material does not include step S1, and epichlorohydrin is not included in step S3, and the rest of the components, component contents and preparation method are the same as example 1.

[0052] Comparative Example 2

[0053] The present comparative example provides a heavy metal recovery material and a preparation method thereof, which is different from Example 1 only in that the preparation method of the heavy metal recovery material does not include step S3, and only the cellulose solution is crosslinked by epichlorohydrin, and the rest of the components, component contents and preparation method are the same as those of Example 1.

[0054] Comparative Example 3

[0055] The present comparative example provides a heavy metal recovery material and a preparation method thereof, which is different from Example 1 only in that in step S3 of the preparation method of the heavy metal recovery material, dimethylamine and di-sec-butylamine are dissolved in deionized water, epichlorohydrin prepared in step S1 is added, and after polymerization, the cellulose solution prepared in step S2 is added, and after mixing, the heavy metal recovery material is obtained by drying, and the rest of the components, component contents and preparation method are the same as those of Example 1.

[0056] Experimental Example 1

[0057] In this experimental example, the heavy metal recovery materials prepared in Examples 1-3 and Comparative Examples 1-3 are subjected to adsorption test. A 50 mg / L cadmium ion solution is prepared by using cadmium chloride, 50 mL of which is measured and placed in a conical flask, the pH is adjusted to 7, 50 mg of the heavy metal recovery material prepared in Examples 1-3 and Comparative Examples 1-3 is added, and the mixture is subjected to oscillation treatment at a speed of 200 rpm under room temperature conditions. Sampling is performed at 5 min, 10 min, 20 min, 30 min, 45 min, 60 min, 75 min, 90 min, 120 min, 150 min, 180 min and 240 min, the water phase filter membrane is used, and the cadmium ion concentration in the supernatant is determined by ICP-OES.

[0058] Figure 3The results of the adsorption performance of cadmium ions of the recycled materials prepared in Examples 1-3 and Comparative Examples 1-3 are shown in the graph, the adsorption of tetracycline on the recycled materials prepared in Examples 1-3 reached equilibrium at about 90 min, and the adsorption capacity after equilibrium reached 71.3-72.5 mg / g, the recycled material prepared in Comparative Example 2 reached equilibrium at about 150 min, and the adsorption capacity after equilibrium was 36.5 mg / g, the recycled material prepared in Comparative Example 1 reached equilibrium at about 120 min, and the adsorption capacity after equilibrium was 48.3 mg / g, and the recycled material prepared in Comparative Example 3 reached equilibrium at about 180 min, and the adsorption capacity after equilibrium was 54.8 mg / g; the adsorption capacity after equilibrium of Comparative Example 1 and Comparative Example 3 showed a decrease in adsorption capacity, indicating that the prepared heavy metal recycling material had desorption of cadmium ions, indicating that the adsorption performance of the heavy metal recycling material was unstable, the heavy metal recycling material prepared in the present application had high adsorption performance for cadmium ions, and could achieve high adsorption capacity, and at the same time, the adsorption performance was stable, the recycled material prepared in the comparative example had significantly fewer adsorption sites, so the adsorption capacity was low, and there was also a desorption situation.

[0059] Experimental Example 2

[0060] In this experimental example, the adsorption and regeneration test of cadmium ions on the recycled materials prepared in Examples 1-3 and Comparative Examples 1-3 was carried out, 50 mg of the recycled materials prepared in Examples 1-3 and Comparative Examples 1-3 was taken as the test sample, and was placed in a 50 mg / L cadmium ion solution, the pH was adjusted to 7, and was oscillated at a speed of 200 rpm at room temperature, after 300 min, the adsorption capacity of the test sample was measured, the test sample was filtered and separated, and was soaked in a 0.1 mol / L hydrochloric acid solution for 3 h, then was washed with deionized water, dried, and then was subjected to adsorption test again, the adsorption-desorption cycle was carried out, after 5 cycles, the adsorption capacity of the test sample in the 5th cycle was measured, and was compared with the initial adsorption capacity;

[0061] Figure 4The results of the adsorption regeneration performance of the recycled materials prepared in Examples 1-3 and Comparative Examples 1-3 are shown in the figure. After 5 regeneration treatments, the adsorption capacities of the recycled materials prepared in Examples 1-3 reached 60.3 mg / g, 59.2 mg / g, 58.740 mg / g or more, respectively. After 5 regeneration treatments, the adsorption capacity of the recycled material prepared in Comparative Example 1 decreased to 15.5 mg / g, the adsorption capacity of the recycled material prepared in Comparative Example 2 decreased to 2.4 mg / g, and the adsorption capacity of the recycled material prepared in Comparative Example 3 decreased to 25.1 mg / g. This shows that the recycled material prepared in the present application has good stability and can be recycled. The recycled material prepared in Comparative Example 1 is modified by intermolecular forces using dimethylamine and di-sec-butylamine. The crosslinking effect of the crosslinking agent containing sulfur is lacking, which reduces the interaction between the cellulose material and the polyamine, resulting in a slower initial adsorption rate of heavy metal ions. At the same time, the adsorption active sites are significantly reduced, resulting in a decrease in adsorption capacity. After multiple cycles, the structure of the recycled material is damaged, the active sites are passivated, the active sites cannot adsorb heavy metal ions, and further reduces the utilization of the recycled material. The recycled material prepared in Comparative Example 2 is actually crosslinked by chloromethylthiophenylsilane. After crosslinking, the cellulose molecule is introduced into the cellulose molecule containing S element group, which increases the adsorption active site and the adsorption rate is the slowest. After crosslinking, the cellulose molecule is compact and the active site does not fully contact the heavy metal ions. After adsorption treatment, it is difficult to desorb heavy metal ions from the recycled material, resulting in a significant decrease in the recycling performance. In the recycled material prepared in Comparative Example 3, dimethylamine, di-sec-butylamine and chloromethylthiophenylsilane first undergo a polymerization reaction to form a polyamine compound, and then are physically blended with cellulose. The polyamine compound and cellulose do not form a complex network structure, resulting in a decrease in adsorption performance and a decrease in the stability of the recycled material.

[0062] Although embodiments of the present application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the application.

[0063] The above description of the present application and its embodiments is not limiting, and the embodiments shown in the drawings are only one of the embodiments of the present application, and the actual application is not limited thereto. In summary, if a person skilled in the art is inspired by it, without departing from the purpose of the present application, without creative design, similar ways and embodiments of the technical solution should belong to the protection scope of the present application.

Claims

1. A preparation method of a sludge heavy metal resource recycling material, characterized in that: Specifically comprising the following steps: ​ S1, dissolve thiourea in deionized water, add sulfuric acid solution, the mass fraction of sulfuric acid solution is 5%, the volume of sulfuric acid solution added is 30%-35% of the volume of thiourea solution, according to the addition amount of neutral alumina in thiourea solution is 10-20g / L, add neutral alumina, after mixing evenly, add epichlorohydrin, adjust the water bath temperature to 30-35℃, stir at the speed of 150-180rpm for 20-40min, then extract the reactants with a mixed solution of n-hexane and chloroform, remove the water, and distill under reduced pressure to obtain epichlorohydrin; S2, according to the mass fraction of microcrystalline cellulose in deionized water is 5%-8%, put the microcrystalline cellulose in deionized water, stir until completely dispersed, according to the volume of sodium hydroxide solution added is 25%-50% of the volume of microcrystalline cellulose solution, add sodium hydroxide solution with mass fraction of 10%-20%, ultrasonic treatment for 50-60min under the power of 400W, then stir the solution to uniform state to obtain cellulose solution; S3, according to the volume ratio between dimethylamine and di-sec-butylamine is 10:1.6-6, dissolve dimethylamine and di-sec-butylamine in deionized water, add to the cellulose solution prepared in step S2, stir and mix evenly, then according to the volume ratio between dimethylamine and epichlorohydrin is 0.8-1.2:1, add epichlorohydrin prepared in step S1, increase the temperature to 65-75℃, stir at the speed of 200-220rpm for 2-3h, dialysis with dialysis bag with molecular weight cutoff of 8000-14000, until the solution is neutral, freeze-drying to obtain sludge heavy metal resource recycling material.

2. The preparation method of the sludge heavy metal resource recovery material according to claim 1, characterized in that: In step S1, the mass concentration of thiourea in deionized water is 0.3-0.4g / mL.

3. The preparation method of the sludge heavy metal resource recovery material according to claim 2, characterized in that: In step S1, the mass volume ratio g / mL of thiourea and epichlorohydrin is 0.90-0.98g / mL.

4. A sludge heavy metal resource recycling material, characterized by, Prepared by the preparation method according to any one of claims 1-3. Prepared by the preparation method according to any one of claims 1-3.

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