A thioureido-based aromatic porous organic polymer and a preparation method and application thereof

Abstract

The application relates to a thioureido aromatic porous organic polymer and a preparation method and application thereof, and belongs to the technical field of functional polymer adsorption materials. The preparation method comprises the following steps: dissolving a plurality of ternary aromatic amine monomers with different electron-donating effects and cheap binary isothiocyanate monomers respectively, mixing and shaking, reacting to obtain a porous organic polymer network, and performing organic gel display; grinding the organic gel into powder, performing solvent exchange in dichloromethane, treating in methanol by using a Soxhlet extractor, and finally drying to obtain the product. The thioureido aromatic porous organic polymer provided by the application has good adsorption selectivity to Au, high adsorption capacity, a wide pH range, good cyclic adsorption performance, a simple preparation method, and high practical application value.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of functional polymer adsorbent preparation and efficient recovery of precious metals, and particularly relates to a thiourea-based aromatic porous organic polymer and a preparation method and application thereof. BACKGROUND

[0002] With the rapid development of the electronic information industry, the replacement speed of electronic products is getting faster and faster. Due to the short service life of electronic equipment, a large amount of electronic waste generated by improper treatment will cause great harm to the environment. The global amount of electronic waste will grow at an average rate of 4% per year, and will reach 74 million tons by 2030. Electronic waste contains many precious metal elements, and the content is generally higher than that of ordinary ore, so it is called urban mine. It is estimated that each ton of mobile phone contains 130 kg of copper, 3.5 kg of silver, 0.34 kg of gold and 0.14 kg of palladium. Most of the precious metals in electronic waste are not properly recovered, but cause great pollution to the environment. Therefore, by recovering precious metal elements from electronic waste, not only can the demand for natural resources and the adverse effects on the environment be reduced, but also the service life of limited precious metal resources can be extended.

[0003] Among electronic waste, gold is the most valuable. Gold recovery from electronic waste begins with pretreatment, which is usually one or more physical separation processes, followed by metal recovery operations such as pyrometallurgy, hydrometallurgy and microbial leaching. Hydrometallurgy is considered to have great potential in the existing industrial solutions for electronic waste treatment. Traditional hydrometallurgical methods include solvent extraction, ion exchange, electrochemical reduction, chemical / physical adsorption, etc., among which chemical / physical adsorption is the most energy-saving and environmentally friendly. However, the hydrometallurgical system is usually complex. This is because the source of the leaching solution--electronic waste is a complex mixture of metals, glass, plastic, ceramic, etc. It is estimated that as many as 69 different chemical elements can be found in electronic waste. Therefore, it is necessary to design and develop efficient adsorbents and achieve selective adsorption of precious metals from complex systems.

[0004] In recent years, porous organic polymers (POPs) have attracted extensive attention as a new chemical / physical adsorbent for precious metals. Porous organic polymers are porous materials composed of light elements such as C, H, N, O, etc., and have the advantages of large specific surface area, good physical and chemical stability, clear chemical composition, wide range of monomer selection, strong designability, etc., and are one of the hotspots of material research. Chinese patent CN 119039545 A reports a guanidyl ionic porous organic polymer material, which can be used as an adsorbent for Au in water, and the saturated adsorption capacity is 1270.76 mg / g, but the adsorption capacity is still far from practical application. Chinese patent CN 110078888 A reports a porous organic polymer connected by thiourea structure, which is used as a Michael reaction catalyst, but the preparation conditions are harsh.

[0005] So far, there has been no report on the use of thiourea-based aromatic porous polymers for recycling Au in electronic waste. SUMMARY

[0006] In view of the problems in the prior art such as complex preparation process of the adsorbent, low gold adsorption capacity of the adsorbent, poor adsorption selectivity, poor cycle stability, etc., the present application proposes a thiourea-based aromatic porous organic polymer and a preparation method and application thereof. The aromatic porous polymer is constructed based on building units with different electron-donating effects, and a thiourea group is introduced to improve the adsorption capacity of Au.

[0007] The technical scheme of the present application is as follows:

[0008] A preparation method of a thiourea-based aromatic porous organic polymer (POPs) comprises the following steps: dissolving ternary aromatic amine monomers and binary isothiocyanate monomers respectively, mixing and shaking, and then reacting to obtain an organic gel; grinding the organic gel into powder, then solvent exchanging in dichloromethane, washing, and finally drying to obtain the product.

[0009] Preferably, the binary isothiocyanate monomer comprises any one of p-phenylene diisothiocyanate (PDI), 4,4'-diisothiocyanato-1,1'-biphenyl, bis(4-isothiocyanatophenyl)disulfide, 4,4'-diisothiocyanato-1,1'-p-terphenyl, 4,4'-diisothiocyanato-3,3',5,5'-tetramethyl-1,1'-biphenyl, and 1,4-diisothiocyanato-2,5-dimethylbenzene.

[0010] The binary isothiocyanate monomer comprises p-phenylene diisothiocyanate (PDI).

[0011] Preferably, the ternary aromatic amine monomer comprises any one of tris(4-aminophenyl)amine (TAPA) and 1,3,5-tris(4-aminophenoxy)benzene (TAPOB).

[0012] Preferably, the dissolving further comprises ultrasonic or microwave treatment.

[0013] Preferably, the dissolving solvent is N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF) or dimethyl sulfoxide (DMSO).

[0014] Preferably, the exchange time of the solvent exchange is 6-12h, and the exchange times is 2-4 times.

[0015] Preferably, the rotation speed of the household flour mill is 12000-22000rpm.

[0016] Preferably, the washing is washing with an organic solvent, the organic solvent is any one or more of methanol, ethanol, propanol and acetone, the treatment temperature is 50-65℃, and the washing times is 6-12 times.

[0017] Preferably, the drying is drying at 60-80℃ under vacuum for 12-24h.

[0018] The application further provides the thioureido aromatic porous organic polymer prepared by the preparation method of the above thioureido aromatic porous organic polymer.

[0019] The application further provides the application of the above thioureido aromatic porous organic polymer as an adsorbent for adsorbing Au in water.

[0020] The principle of adsorbing Au by the thioureido aromatic porous polymer is as follows: 1. The main existing form of gold in the acid leaching solution of waste is [AuCl4] - , and according to the Pearson soft-hard acid-base theory, there is a strong soft-soft interaction between the thiourea structure and [AuCl4]-. 2. Thiourea is a structure rich in hydrogen bonds, and interacts with hydrogen bonds. 3. The amino group in thiourea can be further protonated or positively charged through the Menshutkin reaction, and charge interaction occurs between [AuCl4] - . 4. At the same time, [AuCl4] - has a high redox potential and is more likely to undergo reduction, and the thiourea structure containing N and S can chelate Au(III) while reducing Au(III) to Au(I) and Au(0).

[0021] Compared with the prior art, the application has the following beneficial effects:

[0022] (1) The present application is based on the nucleophilic addition reaction of isothiocyanate and aromatic amine, and the selected ternary aromatic amine monomer is reacted with the binary isothiocyanate monomer to cross-link to form a porous organic polymer network with a thiourea structure. This material has the advantages of simple preparation method, low reaction condition requirement, low cost and easy industrial production.

[0023] (2) The selected thiourea-based POPs have a strong interaction between the thiourea site and gold, and have great selectivity for gold. The maximum adsorption capacity of the adsorbent can reach 4745.87 mg / g. In addition, the adsorbent has a certain reduction effect, and the room temperature reaction can avoid the oxidation of the material, and has good cyclic adsorption performance. It is at the leading level among the current adsorbents, and realizes the environmental protection of room temperature gold refining.

[0024] (3) The thiourea-based POPs prepared by the present application have a wide pH range, and have a high adsorption capacity under the condition of pH 1-7. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 is the infrared spectrum of the adsorbent synthesized in Example 1.

[0026] Figure 2 is the XRD spectrum of the adsorbent synthesized in Example 1.

[0027] Figure 3 is the 13 C NMR spectrum of the adsorbent synthesized in Example 1.

[0028] Figure 4 is the stability infrared spectrum of the adsorbent synthesized in Example 1 under six conditions.

[0029] Figure 5 is the N2 adsorption-desorption curve and pore size distribution of the adsorbent synthesized in Example 1 at 77.4K.

[0030] Figure 6 is the experimental result display of the adsorption capacity of Example 1 under different pH values.

[0031] Figure 7 is the experimental result display of the adsorption kinetics of the adsorbent in Example 2.

[0032] Figure 8 is the experimental result display of the adsorption isotherm of the adsorbent in Example 3.

[0033] Figure 9 is the result display of the maximum adsorption capacity comparison of the adsorbent in Example 3.

[0034] Figure 10 is the experimental result display of the adsorption selectivity of the adsorbent in Example 4.

[0035] Figure 11 are experimental results showing the cycle stability of the adsorbents in Experimental Example 5. DETAILED DESCRIPTION

[0036] In order to make the above objectives, features and advantages of the present application more apparent, specific embodiments of the present application are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one skilled in the art that the present application can be practiced without the specific details given herein. In other instances, well-known methods have not been described in detail in order to avoid obscuring the present application. Therefore, the present application is not limited to the specific embodiments disclosed herein, but only by the claims.

[0037] 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. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application. Unless otherwise indicated, the specific conditions used in the examples are those that are conventional or are those that are indicated to be preferred. The materials used are commercially available unless otherwise indicated.

[0038] Example 1

[0039] (1) Preparation of thioureagroup POPs organic gel based on p-phenylene diisothiocyanate Thioureagroup POPs organic gel was prepared by weighing p-phenylene diisothiocyanate (0.30 mmol) and tris(4-aminophenyl)amine (0.20 mmol) and placing them in two 1 mL centrifuge tubes, respectively, adding 0.2 ml of N,N-dimethylacetamide (DMAc) to each of the two centrifuge tubes, and sonicating for 15 minutes. The solutions in the two centrifuge tubes were then mixed in either of the centrifuge tubes and shaken for 10 s to disperse uniformly, and the formation of a dark brown gel was observed after 15 minutes of reaction at room temperature. The gel was left to stand for 6 h to allow for full reaction, and a thioureagroup POPs organic gel was obtained.

[0040] (2) Preparation of thioureagroup POPs adsorbent powder based on p-phenylene diisothiocyanate

[0041] The organic gel of step (1) was added to a mortar and ground for 10 min using a speed of 5000 / min to obtain a fine particulate gel. The fine particulate gel was added to a 100 ml beaker and 50 ml of dichloromethane was added and mechanically stirred at 200 rpm for 6 h to displace the solvent. The fine particulate gel was then separated by filtration. The above solvent displacement operation was continued for 2 more times. The product obtained was taken in a soxhlet extractor and treated with methanol at 65 degree for 12 h. After this it was taken in a vacuum oven at 80 degree for 12 h to obtain the target product, designated as Thiourea-POP-1, which appeared as a dark brown powder. It was used for gold adsorption and the maximum adsorption capacity was 4745.86 mg / g at 50 degree centigrade.

[0042] The IR spectrum of the adsorbent Thiourea-POP-1 obtained in this example along with the raw monomers is shown in Figure 1. Figure 1 In the spectrum of Thiourea-POP-1, the peaks of p-phenylenediisothiocyanate (PDT) at 2000 cm- 1 and tri(4-aminophenyl)amine at 3300 cm- 1 , 3400 cm- 1 disappeared, indicating complete reaction of the monomers.

[0043] The XRD pattern is shown in Figure 2, indicating that Thiourea-POP-1 is a typical amorphous polymer. Figure 2

[0044] The solid state 13 C NMR spectrum is shown in Figure 3, the peak at 175 ppm is assigned to the thiourea carbon atom, further confirming the formation of the thiourea linkage. Other peaks in the range of 150-110 ppm correspond to the aromatic carbon atoms. Figure 3

[0045] The stability of the adsorbent obtained in this example under six different conditions is shown in Figure 4. From the IR spectra it can be seen that there is no significant change in Thiourea-POP-1 under the six conditions, indicating good stability. Figure 4

[0046] The N2adsorption-desorption curve and pore size distribution of the adsorbent obtained in this example at 77.4 K is shown in Figure 5. From the curve it can be observed that the specific surface area of the material is 40.61 m 2 / g, which is in line with the specific surface area of typical organic gels and the pore structure is mainly mesoporous. Figure 5 Example 2

[0047]

[0048] ​​​​Take p-phenylene diisothiocyanate (0.30 mmol), 1,3,5-tris(4- aminophenoxy) benzene (TAPOB) (0.20 mmol) and place them in two 1 mL centrifuge tubes, add 0.2 ml of N,N-dimethylacetamide (DMAc) to each of the two centrifuge tubes and sonicate for 15 minutes. Then mix the solutions in either of the centrifuge tubes and shake for 10 s to disperse uniformly, formation of light brown gel is observed within 15 minutes of reaction at room temperature, allow the gel to stand for 6 h for complete reaction to get thiourea based POPs organic gel. The organic gel is taken in a flour mill and ground for 10 min at 5000 / min to get small particle gel. The small particle gel is taken in a 100 ml beaker and 50 ml dichloromethane is added and mechanically stirred at 200 rpm for 6 h to replace the solvent. Then the small particle gel is separated by filtration. The above solvent replacement operation is repeated two more times. The product obtained is taken in a soxhlet extractor and treated with methanol at 65 degree for 12 h. After that it is taken in a vacuum oven at 80 degree for 12 h to get the target product, which is named as Thiourea-POP-2, appears as a grey powder and is useful for gold adsorption with a maximum adsorption capacity of 4366.62 mg / g at 50 degree Celsius.

[0049] Example 3

[0050] Take 4,4'-diisothiocyanato-1,1'-biphenyl (0.30 mmol), tris(4- aminophenyl)amine (0.20 mmol) and place them in two 1 mL centrifuge tubes, add 0.2 ml of N,N-dimethylacetamide (DMAc) to each of the two centrifuge tubes and microwave assisted dissolution for 15 minutes. Then mix the solutions in either of the centrifuge tubes and shake for 15 s to disperse uniformly, formation of brown gel is observed within 15 minutes of reaction at room temperature, allow the gel to stand for 6 h for complete reaction to get thiourea based POPs organic gel. The organic gel is taken in a flour mill and ground for 10 min at 5000 / min to get small particle gel. The small particle gel is taken in a 100 ml beaker and 50 ml dichloromethane is added and mechanically stirred at 200 rpm for 6 h to replace the solvent. Then the small particle gel is separated by filtration. The above solvent replacement operation is repeated two more times. The product obtained is washed with hot acetone at 65 degree for 12 h. After that it is taken in a vacuum oven at 80 degree for 12 h to get the target product, which appears as a brown powder. It is useful for gold adsorption with a maximum adsorption capacity of 3124.58 mg / g at 50 degree Celsius.

[0051] Example 4

[0052] Take 1, 4-diisothiocyanato-2, 5-dimethylbenzene (0.30 mmol), 1, 3, 5-tri (4- aminophenoxy) benzene (TAPOB) (0.20 mmol) and place them in two 1 mL centrifuge tubes, add 0.2 ml of N, N-dimethylacetamide (DMAc) to each of the two centrifuge tubes, treat using ultrasonication for 15 minutes. Then mix the solutions in either of the centrifuge tubes and shake for 10 s to disperse uniformly, allow to react for 15 minutes at room temperature to see the formation of a light brown gel, allow the gel to stand for 6 h for complete reaction to obtain an organic gel. Add to a flour mill and grind for 10 min at a speed of 5000 / min to obtain a small particle gel. Add the small particle gel obtained to a 100 ml beaker and add 50 ml of dichloromethane, mechanically stir for 6 h at 200 rpm to displace the solvent. Then separate the small particle gel by filtration. Then continue the above solvent displacement operation for 2 more times. Wash the product obtained with hot acetone at 65 degrees for 12 h. After that, subject it to a vacuum oven at 80 degrees for 12 h to obtain the target product, which appears as a grey powder, which can be used for gold adsorption, with a maximum adsorption capacity of 3785.12 mg / g at 50 degrees Celsius.

[0053] Comparative Example 1

[0054] Take p-phenylene diisothiocyanate (0.30 mmol), 1, 3, 5-tri (4- aminophenoxy) benzene (0.20 mmol) and place them in two 1 mL centrifuge tubes, add 0.2 ml of N, N-dimethylacetamide (DMAc) to each of the two centrifuge tubes, treat using microwave for 15 minutes. Then mix the solutions in either of the centrifuge tubes and shake for 10 s to disperse uniformly, allow to react for 15 minutes at room temperature to see the formation of a brown gel, allow the gel to stand for 6 h for complete reaction to obtain a thiourea-based POP organic gel. Add the organic gel to a flour mill and grind for 10 min at a speed of 5000 / min to obtain a small particle gel. Add the small particle gel obtained to a 100 ml beaker and add 50 ml of dichloromethane, mechanically stir for 6 h at 200 rpm to displace the solvent. Then separate the small particle gel by filtration. Then continue the above solvent displacement operation for 2 more times. Place the product obtained in a soxhlet extractor and treat with methanol at 65 degrees for 12 h. After that, subject it to a vacuum oven at 80 degrees for 12 h to obtain the target product, designated as Thiourea-POP-3, which appears as a brown powder, which can be used for gold adsorption, with a maximum adsorption capacity of 1104.52 mg / g at 50 degrees Celsius.

[0055] Comparative Example 2

[0056] PDI (0.30 mmol), TAPT (0.15 mmol) were weighed and taken in two 1 mL centrifuge tubes, 0.2 ml of N,N-dimethylacetamide (DMAc) was added to each of the centrifuge tubes and sonicated for 15 minutes. The solutions in both the centrifuge tubes were then mixed in either of the centrifuge tubes and shaken for 10 s to get uniformly dispersed, formation of golden yellow gel was observed on reaction for 15 minutes at room temperature, the gel was allowed to stand for 6 h for complete reaction to get thiourea-based POPs organic gel. The organic gel was taken in a mortar and ground for 10 min using 5000 / min speed to get small particulate gel. The small particulate gel was taken in a 100 ml beaker and 50 ml of dichloromethane was added, the solvent exchange was done by mechanical stirring at 200 rpm for 6 h. The small particulate gel was then filtered and separated. The above solvent exchange operation was continued for 2 more times. The product obtained was taken in a soxhlet extractor and treated with methanol at 65 degree for 12 h. After that it was taken in a vacuum oven at 80 degree for 12 h to get the target product, named as Thiourea-POP-4, which appeared as yellow powder and was used for gold adsorption with maximum adsorption capacity of 474.62 mg / g at 50 degree Celsius.

[0057] Comparative Example 3

[0058] PDI (0.30 mmol), TAPT (0.15 mmol) were weighed and taken in two 1 mL centrifuge tubes, 0.2 ml of N,N-dimethylacetamide (DMAc) was added to each of the centrifuge tubes and sonicated for 15 minutes. The solutions in both the centrifuge tubes were then mixed in either of the centrifuge tubes and shaken for 10 s to get uniformly dispersed, formation of golden yellow gel was observed on reaction for 15 minutes at room temperature, the gel was allowed to stand for 6 h for complete reaction to get thiourea-based POPs organic gel. The organic gel was taken in a mortar and ground for 10 min using 5000 / min speed to get small particulate gel. The small particulate gel was taken in a 100 ml beaker and 50 ml of dichloromethane was added, the solvent exchange was done by mechanical stirring at 200 rpm for 6 h. The small particulate gel was then filtered and separated. The above solvent exchange operation was continued for 2 more times. The product obtained was taken in a soxhlet extractor and treated with methanol at 65 degree for 12 h. After that it was taken in a vacuum oven at 80 degree for 12 h to get the target product, named as Thiourea-POP-4, which appeared as yellow powder and was used for gold adsorption with maximum adsorption capacity of 474.62 mg / g at 50 degree Celsius.

[0059] Performance Test

[0060] Experimental Example 1

[0061] Effect of solution pH on gold adsorption capacity

[0062] Accurately weigh 7 portions of 3 mg of Thiourea-POP-1 prepared in Example 1 into 5 ml sample bottles. Prepare Au aqueous solution with initial concentration of 3253.77 ppm (measured by ICP) and adjust the pH of the solution to 1, 2, 3, 4, 5, 6, 7 respectively. Accurately weigh 5 ml of the above Au solution with different pH into the 7 sample bottles respectively. Set the temperature of the constant temperature shaking device to 40 degrees and the speed to 150 r / min. Put the sample bottles into the device and shake for 24 h to reach adsorption equilibrium. Collect the supernatant in the sample bottles and filter, and then detect the concentration of Au ions by inductively coupled plasma optical emission spectrometer (ICP-OES). Calculate the Au adsorption amount Qe (mg / g) at equilibrium by the following equation (1):

[0063] Qe = ((Co-Ce) x V) / m (1);

[0064] In the formula, Co is the initial concentration of Au in the solution (mg / L), Ce is the concentration of Au in the solution at adsorption equilibrium (mg / L), V is the volume of the solution (L), and m is the mass of the adsorbent (g).

[0065] Figure 6 The adsorption capacity at different pH in Experimental Example 1 is shown in the table. It can be seen that Thiourea-POP-1 does not change significantly under the conditions of pH = 1-7, and all show more than 99% removal rate for high concentration Au solution.

[0066] Experimental Example 2

[0067] Adsorption kinetics of the adsorbent

[0068] Accurately weigh 6 portions of 5 mg of Thiourea-POP-1 prepared in Example 1 into 6 50 ml centrifuge tubes, and add 25 ml of 679.50 ppm (determined by ICP) Au solution (pH = 2) into the above 6 centrifuge tubes respectively. Set the temperature of the constant temperature shaking device to 25 degrees and the speed to 150 r / min. Put the sample bottles into the device and shake for 1, 2, 4, 8, 14, 24.67 h respectively, collect the supernatant in the sample bottles and filter, and then detect the concentration of Au ions by inductively coupled plasma optical emission spectrometer (ICP-OES). Calculate the Au adsorption amount Qt (mg / g) at different times by the following equation (2):

[0069] Qt = ((Co-Ct) x V) / m (2)

[0070] In the formula, Co is the initial concentration of Au in the solution (mg / L), Ct is the concentration of Au in the solution at a certain time (mg / L), V is the volume of the solution (L), and m is the mass of the adsorbent (g).

[0071] Figure 7 The adsorption kinetic results of the adsorbent of Experimental Example 2 show that the maximum adsorption capacity of Thiourea-POP-1 can be reached in about 25h, and it is worth mentioning that the longer time is because the selected initial concentration is higher. At the same time, the adsorption of the adsorbent to gold shows chemical adsorption because the fitting degree of the adsorption model and the pseudo-second-order kinetic model is higher.

[0072] Experimental Example 3

[0073] Adsorption isotherm of the adsorbent

[0074] Accurately weigh 5 portions of 3mg of Thiourea-POP-1 prepared in Example 1, and add them into 5 20ml sample bottles respectively, and add 10ml of 100.59, 192.08, 933.62, 1360.65, 1989.85ppm (determined by ICP-OES) gold solution (pH = 2) into the above 5 sample bottles respectively, set the temperature of the constant temperature shaking device to 50 degrees, and set the speed to 150r / min, put the sample bottles into it and shake for 48h to reach equilibrium, collect the supernatant in the sample bottles and filter, and then detect the concentration of gold ions by inductively coupled plasma emission spectrometer (ICP-OES). The maximum adsorption capacity Qe (mg / g) of gold at different concentrations is calculated by using the above-mentioned equation (1). Based on the same operation as above, the maximum adsorption capacity Qe (mg / g) of the four kinds of Thiourea-POP obtained in Examples 2-5 is calculated.

[0075] Figure 8 The adsorption isotherm experimental results of the adsorbent of Experimental Example 3 show that with the increase of the initial concentration of gold ions, the adsorption capacity of Thiourea-POP-1 gradually increases, and the maximum reaches 4745.86mg / g. And the fitting results of the adsorption model are more consistent with the Langmuir model (0.9965). Figure 9 The results of the comparison of the maximum adsorption capacity of the adsorbent in Experimental Example 3 show that the Thiourea-POP-1 with the strongest electron-pushing structure shows the largest adsorption capacity, and the Thiourea-POP-4 with the strongest electron-withdrawing structure shows the smallest adsorption capacity. At the same time, the performance of Thiourea-POP-1S obtained by the preparation method reported in Chinese patent CN110078888A is much worse than that of Thiourea-POP-1, which may be due to the incomplete polymerization reaction in the preparation process of Thiourea-POP-1S, or the oxidation and decomposition of the skeleton in the high-temperature preparation process, which deteriorates the performance of the product.

[0076] Experimental Example 4

[0077] Adsorption selectivity of adsorbent

[0078] Accurately weigh 1 part of 5 mg of Thiourea-POP-1 prepared in Example 1 into a 20 ml sample bottle, and add 10 ml of a mixed ion solution containing Ca(II), Co(II), Cu(II), Fe(III), K(I), Mg(II), Mn(II), Na(I), Ni(II), Zn(II), Au(iii) at a concentration of 100 ppm (pH = 2) to the sample bottle. Set the temperature of the constant temperature shaking device to 25 degrees and the speed to 150 r / min. Shake the sample bottle in the device for 48 h to reach equilibrium. Collect the supernatant in the sample bottle and filter, and then detect the concentration of the mixed solution by inductively coupled plasma optical emission spectrometer (ICP-OES). Calculate the adsorption capacity Qe(mg / g) of the mixed ions at different concentrations using the above-mentioned equation (1).

[0079] Figure 10 The adsorption selectivity experiment results of the adsorbent of Experimental Example 4 are shown. It can be seen that the adsorbent exhibits high selectivity, and the removal rate of gold can be close to 100%, while other metals exhibit lower removal rates.

[0080] Experimental Example 5

[0081] Cyclic stability of adsorbent

[0082] Accurately weigh 1 part of 3 mg of Thiourea-POP-1 prepared in Example 1 into a 20 ml sample bottle, and add 10 ml of a 200 ppm gold solution (pH = 2) to the sample bottle. Set the temperature of the constant temperature shaking device to 25 degrees and the speed to 150 r / min. Shake the sample bottle in the device for 24 h to reach equilibrium. Collect the supernatant in the sample bottle and filter, and then detect the concentration of gold by inductively coupled plasma optical emission spectrometer (ICP-OES). After adsorption is completed, filter the adsorbent, repeatedly rinse with deionized water, and dry at 80°C under vacuum for 12 h. Then put the adsorbent into 10 mL of 1M thiourea hydrochloride solution (hydrochloric acid, thiourea concentration is 1M) and stir at room temperature for 10 h to desorb. Then repeatedly rinse the desorbed adsorbent with deionized water and dry at 80°C under vacuum for 12 h to obtain a new adsorbent and repeat the above operation. Calculate the adsorption capacity Qe(mg / g) of the mixed ions at different concentrations using the above-mentioned equation (1).

[0083] Figure 11The results of the cycle stability experiment of the adsorbent of experimental example 5 show that the adsorbent can maintain a gold removal rate of more than 85% in the first 5 cycles, indicating that the adsorbent has good cycle performance.

[0084] 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. The terminology used in the description herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. Various technical features are described in this detailed description. Many of the features can be used in combinations other than the combinations explicitly described herein without departing from the scope of the application. The above described features can be combined in any manner within the scope of the application unless specifically noted otherwise.

Claims

1. A method for preparing a thioureido aromatic porous organic polymer, characterized by, The method comprises the following steps: dissolving ternary aromatic amine monomers and binary isothiocyanate monomers respectively, mixing, shaking, reacting at room temperature to obtain a brown gel, and standing to obtain an organic gel; grinding the organic gel into powder, solvent exchanging in dichloromethane, washing, and finally drying to obtain the product; the binary isothiocyanate monomers are selected from any one or more of p-phenylene diisothiocyanate, 4,4'-diisothiocyanato-1,1'-biphenyl, bis(4-isothiocyanatophenyl)disulfide, 4,4'-diisothiocyanato-1,1'-p-terphenyl, 4,4'-diisothiocyanato-3,3',5,5'-tetramethyl-1,1'-biphenyl, and 1,4-diisothiocyanato-2,5-dimethylbenzene; the ternary aromatic amine monomers include any one of tris(4-aminophenyl)amine and 1,3,5-tris(4-aminophenoxy)benzene; the solvent exchanging time is 6-12 hours, and the exchanging times are 2-4 times.

2. The production method according to claim 1, characterized by, The dissolving further comprises ultrasonic treatment and microwave treatment.

3. The preparation method according to claim 1, characterized in that, The grinding into powder is performed by a household grinding machine at a rotating speed of 12000-22000 rpm.

4. The production method according to claim 1, characterized by, The washing is performed by using an organic solvent, the organic solvent is any one or more of methanol, ethanol, propanol and acetone, the washing temperature is 50-65 DEG C, and the washing times are 6-12 times.

5. The preparation method according to claim 1, characterized in that, The drying is performed at 60-80 DEG C under vacuum for 12-24 hours. 6.The thioureido aromatic porous organic polymer prepared by the method of any one of claims 1-5. 7.The application of the thioureido aromatic porous organic polymer of claim 6 as an adsorbent for adsorbing Au in water.

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