A new psychoactive substance adsorbent and its use

Abstract

The application belongs to the technical field of water treatment, and particularly relates to a new psychoactive substance adsorbent and application thereof. The preparation method of the adsorbent comprises the following steps: (1) mixing and reacting activated shrimp shell biomass and ferroferric oxide nano magnetic material, drying, and pyrolyzing to obtain Fe3O4@BC; (2) mixing and reacting Fe3O4@BC and ZIF-8 to obtain Fe3O4@BC@ZIF-8; and (3) mixing and reacting a eutectic solvent with Fe3O4@BC@ZIF-8 to obtain the new psychoactive substance adsorbent. The adsorbent has strong adsorption capacity for 4-methyl methcathinone, methcathinone, amphetamine, methamphetamine and ephedrine, and the adsorption efficiency can reach 98% for 4-methyl methcathinone in particular.

Description

Technical Field

[0001] This invention belongs to the field of water treatment technology, specifically relating to a novel adsorbent for psychoactive substances and its application. Background Technology

[0002] New psychoactive substances, also known as "designer drugs" or "laboratory drugs," are drug analogues obtained by criminals through chemical modifications of controlled drugs to evade prosecution. When ingested, they affect thinking, emotions, will, and behavior, and have similar or stronger stimulant, hallucinogenic, and anesthetic effects than controlled drugs.

[0003] The main sources of new psychoactive substances (NPS) residues and their metabolites in wastewater are the excrement of drug users, substances flushed away by drug users during raids to destroy evidence, and wastewater discharged from drug manufacturing sites. Due to their high biological activity, non-volatile nature, and difficulty in biodegradation, they easily accumulate in aquatic environments, causing pollution to ecosystems. Current research both domestically and internationally has shown that NPS are widely detected in urban wastewater and surface water.

[0004] Therefore, developing an adsorbent that can adsorb new psychoactive substances is of great scientific and practical significance for reducing ecological and environmental risks. Summary of the Invention

[0005] To address the aforementioned problems, one objective of this invention is to provide a novel adsorbent for psychoactive substances. This novel adsorbent is obtained by reacting magnetized shrimp shell biomass with ZIF-8 and then modifying it with a eutectic solvent. It exhibits strong adsorption capacity for 4-methylmethcathinone, methcathinone, amphetamine, methamphetamine, and ephedrine.

[0006] To achieve the above objectives, the present invention can adopt the following technical solutions:

[0007] The present invention provides a novel adsorbent for psychoactive substances, the preparation method of which includes: (1) mixing activated shrimp shell biomass with iron oxide nanomagnetic material, drying and pyrolyzing to obtain Fe3O4@BC; (2) mixing Fe3O4@BC and ZIF-8 to obtain Fe3O4@BC@ZIF-8; (3) mixing a eutectic solvent with Fe3O4@BC@ZIF-8 to obtain the novel adsorbent for psychoactive substances.

[0008] Another aspect of the present invention provides the application of the above-mentioned novel psychoactive substance adsorbent in wastewater treatment, wherein the wastewater contains one or more of 4-methylmethcathinone, methcathinone, amphetamine, methamphetamine and ephedrine.

[0009] The beneficial effects of this invention include at least the following:

[0010] (1) The new psychoactive substance adsorbent provided by the present invention has a strong adsorption capacity for 4-methylmethcathinone, methcathinone, amphetamine, methamphetamine and ephedrine, especially for 4-methylmethcathinone, the adsorption efficiency can reach 98%;

[0011] (2) The new psychoactive substance adsorbent provided by the present invention has a magnetic structure that is easy to recover under an external magnetic field, thereby overcoming the problem that existing adsorbents are not easy to recover from wastewater, thus avoiding secondary pollution of water bodies. Attached Figure Description

[0012] Figure 1 These are scanning electron microscope images of Fe3O4@BC, Fe3O4@BC@ZIF-8 and Fe3O4@BC@ZIF-8@BTBAC-Lac prepared in Example 1 of this invention;

[0013] Figure 2 Infrared spectra of Fe3O4@BC, Fe3O4@BC@ZIF-8 and the final Fe3O4@BC@ZIF-8@BTBAC-Lac nanomagnetic adsorbents prepared in Example 1 of the present invention;

[0014] Figure 3 The magnetic hysteresis regression curves of Fe3O4@BC, Fe3O4@BC@ZIF-8 and the final Fe3O4@BC@ZIF-8@BTBAC-Lac nanomagnetic adsorbent prepared in Example 1 of this invention are shown.

[0015] Figure 4 The graph shows the selective adsorption capacity of the Fe3O4@BC@ZIF-8@BTBAC-Lac nanomagnetic adsorbent prepared in Example 1 of this invention for various psychoactive substances.

[0016] Figure 5 The adsorption efficiency of Fe3O4@BC for 4-methylmethcathinone prepared with different activator ratios and tube furnace pyrolysis temperatures;

[0017] Figure 6 The adsorption efficiency of Fe3O4@BC@ZIF-8 prepared with different ratios of ZIF-8 and Fe3O4@BC for 4-methylmethcathinone;

[0018] Figure 7 The adsorption efficiency of adsorbents prepared with eutectic solvents of different molar ratios for 4-methylmethcathinone;

[0019] Figure 8 The adsorption efficiency of adsorbents prepared for 4-methylmethcathinone using different eutectic solvents. Detailed Implementation

[0020] The embodiments described are provided to better illustrate the present invention, but are not intended to limit the scope of the invention to the embodiments described. Therefore, non-essential improvements and adjustments made to the embodiments by those skilled in the art based on the above description are still within the scope of protection of the present invention.

[0021] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. Singular expressions include plural expressions unless they have a distinct meaning in the context. As used herein, it should be understood that terms such as “comprising,” “having,” “including,” are intended to indicate the presence of a feature, number, operation, material, or combination thereof. The terminology of the invention is disclosed in the specification and is not intended to exclude the possibility that one or more other features, numbers, operations, materials, or combinations thereof may be present or added. As used herein, “ / ” may be interpreted as “and” or “or,” depending on the context.

[0022] This invention provides a novel adsorbent for psychoactive substances, the preparation method of which includes: (1) mixing activated shrimp shell biomass with iron oxide nanomagnetic material, drying, and pyrolyzing to obtain Fe3O4@BC; (2) mixing Fe3O4@BC and ZIF-8 to obtain Fe3O4@BC@ZIF-8; (3) mixing a eutectic solvent with Fe3O4@BC@ZIF-8 to obtain the novel adsorbent for psychoactive substances.

[0023] It should be noted that in the above-mentioned preparation method of the new psychoactive substance adsorbent, the shrimp shell is the shell of a shrimp species known in the art, such as the tiger prawn (Penaeus vannamei). Furthermore, it should be understood that the operational terms "mixing," "drying," and "pyrolysis" in the above preparation method are all conventional operational terms in the art.

[0024] It should also be noted that the iron(II) oxide nanomagnetic material in step (1) above is prepared by a coprecipitation method known in the art. In some specific embodiments, it may include: weighing ferrous salt and ferric salt according to a certain molar ratio, adding ferrous salt and ferric salt to a three-necked flask containing 100mL-120mL of deionized water under nitrogen protection, heating in a water bath and keeping it at 55℃-65℃, stirring for 25min-35min, and then rapidly adding 8mL-12mL of concentrated ammonia solution with a mass concentration of 28%-30% under stirring conditions, and keeping it at the temperature for 30min-35min after the addition is complete to obtain iron(II) oxide nanomagnetic material; wherein, the molar ratio of ferrous salt and ferric salt can be 1:(1-3).

[0025] It should also be noted that ZIF-8 has the variability of ordered network structure, designability, modifiability, and ultra-large specific surface area. The purpose of using ZIF-8 to modify Fe3O4@BC is to give Fe3O4@BC@ZIF-8 higher adsorption performance. The purpose of using a eutectic solvent to modify Fe3O4@BC@ZIF-8 in step (3) is to give the adsorbent a wealth of multifunctional functional groups (such as N and O atoms and corresponding groups), so that there are a large number of chemical sites in the adsorbent that can be used as adsorption sites for new psychoactive substances, especially 4-methylmethcathinone, thereby overcoming the problems of poor adsorption capacity and poor interaction between existing adsorbents and new psychoactive substances (4-methylmethcathinone).

[0026] In some specific embodiments, in step (3) above, the eutectic solvent can be selected from one or more combinations of benzyltributylammonium chloride-lactic acid, choline chloride-lactic acid, tetrabutylammonium chloride-lactic acid, choline chloride-ethylene glycol, or choline chloride-glycerol. It should be noted that the eutectic solvent in step (3) above is a eutectic solvent known in the art, but different eutectic solvents have different adsorption capacities for the prepared new psychoactive substance adsorbent.

[0027] In some specific embodiments, the aforementioned eutectic solvent is preferably benzyltributylammonium chloride-lactic acid, wherein the molar ratio of benzyltributylammonium chloride to lactic acid can be 1:(2-4). It should be noted that in this invention, the adsorption effects of the new psychoactive substance adsorbents prepared by different selections of eutectic solvents vary significantly. Benzyltributylammonium chloride-lactic acid is preferred, as the adsorbent prepared with it can achieve an adsorption efficiency of 98% for 4-methylmethcathinone, which is significantly better than choline chloride-lactic acid (93%), tetrabutylammonium chloride-lactic acid (90%), choline chloride-ethylene glycol (88%), and choline chloride-glycerol (84%).

[0028] It should also be noted that different solvent ratios in the eutectic solvent can affect the adsorption efficiency of the prepared adsorbent. For example, when the eutectic solvent is benzyltributylammonium chloride-lactic acid, the molar ratio can preferably be 1:2 or 1:4, with 1:4 being more preferred. When the ratio is 1:4, the adsorption efficiency of the new psychoactive substance adsorbent for 4-methylmethcathinone can reach 98%, which is much higher than the adsorption efficiency when the molar ratio is 1:2.

[0029] In some specific embodiments, in the above-mentioned 4-methylmethcathinone adsorbent, the preparation method of the eutectic solvent in step (3) of the preparation method is known in the art, such as heating the hydrogen bond donor (lactic acid, ethylene glycol or glycerol) and the hydrogen bond acceptor (benzyltributylammonium chloride, choline chloride or tetrabutylammonium chloride) in a specific molar ratio and keeping the temperature at 85℃-95℃ until a uniform transparent solution is formed.

[0030] In some specific embodiments, the preparation method of activated shrimp shell biomass in step (1) above may include: mixing shrimp shell powder and KOH and dissolving them in water to activate the activated shrimp shell biomass, wherein the mass ratio of shrimp shell powder to KOH is 1:(1-3).

[0031] It should be noted that the adsorption capacity of Fe3O4@BC prepared by different mass ratios of shrimp shell powder and KOH varies. The preferred ratio is 1:3. When the ratio is 1:3, the adsorption efficiency of Fe3O4@BC for 4-methylcathinone can reach 73%, which is much higher than other ratios, such as 1:1 (49%) and 1:2 (57%).

[0032] It should also be noted that in the above-mentioned method for preparing new psychoactive adsorbents, mixing shrimp shell biomass and iron oxide magnetic nanomaterials together is to ensure that iron is uniformly dispersed in the material, and magnetic biochar material will be formed after pyrolysis; ZIF-8 is used first to improve the pore structure of the material, thereby providing more sites for the introduction of eutectic solvent.

[0033] In some specific embodiments, the preparation method of the above-mentioned activated shrimp shell biomass may specifically include: washing and drying the shrimp shells of Penaeus chinensis (prawns); crushing them with a pulverizer and passing them through a 100-mesh sieve to obtain shrimp shell powder; then mixing the shrimp shell powder with KOH aqueous solution, stirring evenly, and letting it stand for 3 hours to obtain activated shrimp shell biomass.

[0034] In some specific embodiments, the pyrolysis temperature in step (1) above can be 500℃-700℃. It should be noted that the adsorption efficiency of Fe3O4@BC prepared at different pyrolysis temperatures for 4-methylmethcathinone varies. For example, when the mass ratio of shrimp shell powder to KOH is 1:3, the adsorption efficiency of Fe3O4@BC prepared by pyrolysis at 600℃ for 4-methylmethcathinone can reach 73%, which is much higher than that at 500℃ (67%) or 700℃ (24%). Therefore, 600℃ is more preferred in this invention.

[0035] In some specific embodiments, the preparation method of the above-mentioned Fe3O4@BC may include: mixing and stirring KOH-activated shrimp shell biomass with iron oxide nanomagnetic material for 12 hours, separating the black product under the action of an external magnetic field, washing the separated black product alternately with anhydrous ethanol and deionized water 4-5 times, drying at 50℃-65℃, placing the dried black product in a tube furnace, heating to a specific temperature at a heating rate of 5ºC / min, controlling the temperature for 2 hours, and cooling to room temperature. After grinding the black product, immersing it in a beaker containing 1 mol / L hydrochloric acid, washing it repeatedly until the pH of the filtrate is neutral, separating the sediment with an external magnet to obtain Fe3O4@BC.

[0036] In some specific embodiments, the mass ratio of ZIF-8 to Fe3O4@BC in step (2) above can be 1:(8-15). It should be noted that the adsorption efficiency of Fe3O4@BC@ZIF-8 prepared with different ZIF-8 to Fe3O4@BC mass ratios for 4-methylcathinone varies, within the range of 1:(8-15), such as 1:0, 1:5, 1:8, 1:10, 1:12, or 1:15. Specifically, when the mass ratio of ZIF-8 to Fe3O4@BC is 1:10, the adsorption efficiency of Fe3O4@BC@ZIF-8 can reach over 76%, far higher than other ratios. It should be understood that the amount of solvent used during modification (ethanol or methanol, etc.) can be set according to specific circumstances, selecting an amount sufficient to ensure adequate dispersion of ZIF-8 and Fe3O4@BC.

[0037] In some specific embodiments, the mass ratio of Fe3O4@BC@ZIF-8 to the volume ratio of the eutectic solvent is 10:1. It should be noted that the mass ratio of Fe3O4@BC@ZIF-8 to the volume ratio of the BTBAC-Lac eutectic solvent is a ratio in the same class of international units, such as g:mL or kg:L, and then calculated accordingly.

[0038] Another embodiment of the present invention provides the application of the above-mentioned novel psychoactive substance adsorbent in wastewater treatment, wherein the wastewater contains one or more of 4-methylmethcathinone, methcathinone, amphetamine, methamphetamine, and ephedrine. It should be noted that the above-mentioned novel psychoactive substance adsorbent has good adsorption capacity for 4-methylmethcathinone, methcathinone, amphetamine, methamphetamine, and ephedrine, especially for 4-methylmethcathinone, where its adsorption efficiency can reach over 98%, far superior to other novel psychoactive substances. Therefore, the novel psychoactive substance adsorbent of the present invention has good selectivity for 4-methylmethcathinone, solving the problems of existing 4-methylmethcathinone adsorbents having a broad spectrum of chemical sites that adsorb pollutants but cannot specifically remove 4-methylmethcathinone; and limited chemical sites resulting in low adsorption efficiency.

[0039] It should also be noted that, in some specific embodiments, when adsorbing new psychoactive substances from the aquatic environment, the aqueous solution of the new psychoactive substances in the aquatic environment can be concentrated first using enrichment methods known in the art, and then adsorbed. Furthermore, the concentration of the new psychoactive substances can be further detected after adsorption.

[0040] To better understand the present invention, specific examples are provided below to further illustrate the content of the present invention, but the content of the present invention is not limited to the examples below.

[0041] In the following examples, the adsorption rate (%) was tested and calculated as follows: 1 mg of adsorbent sample was weighed and placed in a 5 mL glass vial, and then 3 mL of 4-methylmethcathinone solution (pH=7) with an initial concentration of 300 ng / mL was added. The solution was shaken thoroughly at 25 °C and 150 rpm for 60 min. In the reference standard, no adsorbent sample was added, and the other operations were the same. Then, solid-liquid separation was performed using an external magnetic field, and the supernatant was filtered through a 0.22 μm filter membrane. The filtrate was used to analyze the residual amount of 4-methylmethcathinone, and the analysis was performed using UPLC-MS / MS. The adsorption rate (%) was calculated according to equation (1):

[0042]

[0043] Where C0 (ng / mL) and V (mL) represent the initial concentration and solution volume, respectively. e (ng / mL) is the concentration of residual 4-methylmethcathinone in the supernatant after adsorption.

[0044] Example 1: Preparation of a novel psychoactive substance adsorbent

[0045] (1) Preparation of shrimp shell biomass: Wash and dry the shrimp shells of the new shrimp (Penaeus chinensis); crush them with a pulverizer and sieve them with a 100-mesh sieve; weigh the shrimp shell powder and KOH solid at a mass ratio of 1:3 and put them into beakers respectively; dissolve KOH in 20mL of deionized water to form KOH solution; add KOH solution to shrimp shell powder; stir evenly and let stand for 3h to obtain activated shrimp shell biomass;

[0046] (2) Preparation of magnetic nanomaterial Fe3O4@BC by coprecipitation method: Weigh ferrous salt and ferric salt at a molar ratio of 1:2; under nitrogen protection, add ferrous salt and ferric salt to a three-necked flask containing 100mL deionized water heated in a water bath and kept at 60℃, and then stir for 30min. Then, continue to add 10mL of concentrated ammonia solution with a mass concentration of 28% under stirring. After the addition is complete, keep stirring at 60℃ for 30min; then add activated shrimp shell biomass that has been standing for 3 hours in step (1), and continue stirring for 12h after the addition is complete; separate the black product under the action of an external magnetic field, wash the separated black product with anhydrous ethanol and deionized water alternately 5 times, dry at 60℃, place the dried black product in a tube furnace, react at 600℃ for 2h, cool to room temperature, grind, and sieve to obtain magnetic nanomaterial Fe3O4@BC;

[0047] (3) Preparation of Fe3O4@BC@ZIF-8 by post-modification method: 10 mg of metal-organic framework ZIF-8 powder was activated at 140 °C for 3 h, then dispersed in 100 mL of anhydrous methanol solution and sonicated for 2 h until a uniformly dispersed ZIF-8 dispersion was obtained; 100 mg of Fe3O4@BC powder prepared in step (2) was added and stirred for 24 h; the solid mixture was separated under the action of an external magnetic field, and the separated solid mixture was washed with anhydrous methanol and deionized water alternately 4-5 times and dried at 60 °C to obtain Fe3O4@BC@ZIF-8 powder;

[0048] (4) Preparation of Fe3O4@BC@ZIF-8@BTBAC-Lac by post-modification method: First, BTBAC-Lac eutectic solvent was prepared; benzyltributylammonium chloride and lactic acid were heated in a water bath at 80°C with a molar ratio of 1:4 and stirred until a uniform transparent solution was obtained to obtain BTBAC-Lac eutectic solvent; 100 mg of Fe3O4@BC@ZIF-8 powder prepared in step (3) was uniformly dispersed in 100 mL of anhydrous ethanol, and then 10 mL of BTBAC-Lac eutectic solvent was added and stirred at room temperature for 1 h; the solid mixture was separated under the action of an external magnetic field, and the separated product was washed 5 times alternately with anhydrous methanol and deionized water and dried at 50°C to obtain Fe3O4@BC@ZIF-8@BTBAC-Lac (new psychoactive substance adsorbent).

[0049] Example 2 Characterization of novel psychoactive substance adsorbents and related substances

[0050] The Fe3O4@BC, Fe3O4@BC@ZIF-8, and Fe3O4@BC@ZIF-8@BTBAC-Lac prepared in Example 1 above were observed using a scanning electron microscope. The results are as follows: Figure 1 As shown, A is a scanning electron microscope image of Fe3O4@BC, which shows its disordered nanoporous structure and irregularly aggregated rough surface; B is a scanning electron microscope image of Fe3O4@BC@ZIF-8, which shows ZIF-8 aggregation, and the surface roughness of Fe3O4@BC@ZIF-8 is significantly increased compared to Fe3O4@BC; C is a scanning electron microscope image of Fe3O4@BC@ZIF-8@BTBAC-Lac, which shows that its particle size is larger than that of Fe3O4@BC and Fe3O4@BC@ZIF-8, and it has abundant open bowl-shaped pores and a three-dimensional layered network.

[0051] The Fe3O4@BC, Fe3O4@BC@ZIF-8, and Fe3O4@BC@ZIF-8@BTBAC-Lac prepared in Example 1 above were subjected to infrared spectroscopy. The test results are as follows: Figure 2 As shown, A is the infrared spectrum of Fe3O4@BC. From the figure, it can be seen that at 567 cm⁻¹... -1 The absorption peak for the stretching vibration of Fe-O is 3418 cm⁻¹. -1 The absorption peaks are for the stretching vibration of OH, at 1435, 876, and 716 cm⁻¹. -1 B represents the absorption peak of calcium carbonate minerals in shrimp shells; B is the infrared spectrum of Fe3O4@BC@ZIF-8, 567 cm⁻¹. -1 The absorption peak for the stretching vibration of Fe-O is 3444 cm⁻¹. -1 The absorption peaks are for the stretching vibration of OH, at 1435, 876, and 716 cm⁻¹. -1 It is the absorption peak of calcium carbonate minerals in the shrimp shell, 479 cm⁻¹ -1 The absorption peak is the Zn–N stretching vibration peak, at 1615 cm⁻¹. -1 The absorption peak is the stretching vibration of C=N; C is the infrared spectrum of Fe3O4@BC@ZIF-8@BTBAC-Lac, 3420 cm⁻¹. -1 The absorption peak is the stretching vibration of OH, at 1620 cm⁻¹. -1 The absorption peak for the stretching vibrations of C=C, C=O, and C=N is 567 cm⁻¹. -1 and 479 cm -1The absorption peaks are for the stretching vibrations of Fe-O and Zn-O, respectively. Furthermore, compared to Fe3O4@BC and Fe3O4@BC@ZIF-8, the disappearance of the absorption peak for calcium carbonate in Fe3O4@BC@ZIF-8@BTBAC-Lac indicates the removal of calcium carbonate minerals. Additionally, the 3420 cm⁻¹ peak in Fe3O4@BC@ZIF-8@BTBAC-Lac... -1 and 1620cm -1 The broad peaks and high intensities at these spectral values ​​indicate that the content of hydroxyl and carboxyl groups grafted onto the Fe3O4@BC@ZIF-8@BTBAC-Lac surface was significantly increased due to the introduction of BTBAC-Lac during the post-modification process. The above infrared spectral results demonstrate that the synthesis of the nanomagnetic adsorbents was successful.

[0052] Hysteresis regression curves were plotted for Fe3O4@BC, Fe3O4@BC@ZIF-8 and the prepared Fe3O4@BC@ZIF-8@BTBAC-Lac from Example 1. The results are as follows. Figure 3 As shown, the results indicate that the Fe3O4@BC@ZIF-8@BTBAC-Lac nanoparticles exhibit a closed magnetization curve with hysteresis. Due to the grafting of non-magnetic ZIF-8 particles and the impregnation with a eutectic solvent layer, the signal from the magnetic core is shielded, resulting in a weak saturation magnetization of approximately 28.31 emu / g for Fe3O4@BC@ZIF-8@BTBAC-Lac.

[0053] The adsorption efficiency of the Fe3O4@BC@ZIF-8@BTBAC-Lac prepared above for 4-methylmethcathinone, methcathinone, amphetamine, methamphetamine, and ephedrine was tested according to the above method. The results are as follows: Figure 4 As shown in the figure, compared with the above-mentioned psychoactive substances, Fe3O4@BC@ZIF-8@BTBAC-Lac has the highest adsorption rate for 4-methylmethcathinone and exhibits high selective adsorption.

[0054] Example 3: Preparation of Fe3O4@BC by different mass ratios of shrimp shell powder and KOH solids and calcination temperatures.

[0055] In Example 1, the mass ratio of 1:3 in step (1) was set to 1:1 and 1:2, and the 600℃ in step (2) was set to 500℃ and 700℃ respectively. Other steps were the same as in Example 1, and Fe3O4@BC (1:1, 600℃), Fe3O4@BC (1:2, 600℃), Fe3O4@BC (1:3, 500℃) and Fe3O4@BC (1:3, 700℃) were prepared respectively.

[0056] The adsorption efficiencies of Fe3O4@BC (1:3, 600℃) prepared in Example 1 and the Fe3O4@BC (1:1, 600℃), Fe3O4@BC (1:2, 600℃), Fe3O4@BC (1:3, 500℃), and Fe3O4@BC (1:3, 700℃) prepared in Example 3 for 4-methylmethcathinone were tested respectively (tested according to the above method). The results are as follows. Figure 5 As shown, the highest adsorption efficiency (approximately 73%) of Fe3O4@BC was obtained when the mass ratio of shrimp shell powder to KOH was 1:3 and the pyrolysis temperature in the tubular furnace was 600℃. When the mass ratio of shrimp shell powder to KOH was 1:1 and 1:2, and the pyrolysis temperature was 600℃, the adsorption efficiency of Fe3O4@BC decreased (approximately 49% and 57%, respectively). When the mass ratio of shrimp shell powder to KOH was 1:3 and the temperature was lowered to 500℃, the adsorption efficiency of Fe3O4@BC decreased somewhat (approximately 67%). When the mass ratio of shrimp shell powder to KOH was 1:3 and the temperature was raised to 700℃, the adsorption efficiency of Fe3O4@BC decreased sharply (approximately 24%).

[0057] In summary, in this invention, the mass ratio of shrimp shell powder to KOH is set to 1:(1-3), the pyrolysis temperature of the tubular furnace is set to 500℃-700℃, preferably 1:3 and 600℃.

[0058] Example 4: Preparation of Fe3O4@BC@ZIF-8 with different mass ratios of ZIF-8 and Fe3O4@BC

[0059] The amount of Fe3O4@BC added in step (3) of Example 1 was set to 0 mg, 50 mg, 80 mg, 120 mg and 150 mg respectively, that is, the mass ratio of ZIF-8 to Fe3O4@BC was 1:0, 1:5, 1:8, 1:12 and 1:15 respectively. Other steps were the same as in Example 1, and ZIF-8, Fe3O4@BC@ZIF-8 (1:5), Fe3O4@BC@ZIF-8 (1:8), Fe3O4@BC@ZIF-8 (1:12) and Fe3O4@BC@ZIF-8 (1:15) were prepared respectively.

[0060] The adsorption efficiencies of Fe3O4@BC@ZIF-8 (1:10) prepared in Example 1, and ZIF-8, Fe3O4@BC@ZIF-8 (1:5), Fe3O4@BC@ZIF-8 (1:8), Fe3O4@BC@ZIF-8 (1:12), and Fe3O4@BC@ZIF-8 (1:15) prepared in Example 4 for 4-methylmethcathinone were tested respectively. The results are as follows: Figure 6As shown, different mass ratios of ZIF-8 and Fe3O4@BC resulted in variations in the adsorption efficiency of Fe3O4@BC@ZIF-8 for methikatone (tested according to the above method). The best adsorption efficiency (approximately 76%) was observed when the ZIF-8 to Fe3O4@BC ratio was 10 mg:100 mg (mass ratio 1:10). The adsorption efficiencies of Fe3O4@BC@ZIF-8 prepared at ratios of 10 mg:80 mg (mass ratio 1:8) and 10 mg:120 mg (mass ratio 1:12) were similar (approximately 72%). The adsorption efficiencies of Fe3O4@BC@ZIF-8 prepared at ratios of 10 mg:150 mg (mass ratio 1:15) and 10 mg:50 mg (mass ratio 1:5) were the next best, while pure ZIF-8 exhibited the worst adsorption efficiency. Therefore, the mass ratio of ZIF-8 to Fe3O4@BC in this invention can be set to 1:(8-15), preferably 1:10.

[0061] Example 5: Preparation of Fe3O4@BC@ZIF-8@BTBAC-Lac from different molar ratios of benzyltributylammonium chloride and lactic acid

[0062] In step (4) of Example 1, the molar ratio of benzyltributylammonium chloride and lactic acid in the BTBAC-Lac eutectic solvent was replaced from 1:4 to 1:2, and the other steps were the same as in Example 1, to prepare Fe3O4@BC@ZIF-8@BTBAC-Lac (1:2).

[0063] The adsorption efficiencies of Fe3O4@BC@ZIF-8@BTBAC-Lac (1:4) prepared in Example 1 and Fe3O4@BC@ZIF-8@BTBAC-Lac (1:2) prepared in Example 5 for 4-methylmethcathinone were tested respectively (tested according to the above method), and the results are as follows. Figure 7 As shown, when the molar ratio of benzyltributylammonium chloride to lactic acid is 1:2, the adsorption efficiency of the prepared Fe3O4@BC@ZIF-8@BTBAC-Lac (1:2) is about 93%, which is about 5% lower than the adsorption efficiency of Fe3O4@BC@ZIF-8@BTBAC-Lac (1:4) prepared when the molar ratio of benzyltributylammonium chloride to lactic acid is 1:4 (tested according to the above method). Therefore, the preferred molar ratio of benzyltributylammonium chloride to lactic acid in this invention is 1:4.

[0064] Example 6: Preparation of adsorbents using different eutectic solvents

[0065] The eutectic solvent BTBAC-Lac in step (4) of Example 1 was replaced with ChCl-Lac, TBAC-Lac, ChCl-EG and ChCl-Gly, and the other steps were the same as in Example 1, respectively, to prepare Fe3O4@BC@ZIF-8@ChCl-Lac, Fe3O4@BC@ZIF-8@TBAC-Lac, Fe3O4@BC@ZIF-8@ChCl-EG and Fe3O4@BC@ZIF-8@ChCl-Gly.

[0066] The adsorption efficiencies of Fe3O4@BC@ZIF-8@BTBAC-Lac (BTBAC-Lac) prepared in Example 1, and Fe3O4@BC@ZIF-8@ChCl-Lac (ChCl-Lac), Fe3O4@BC@ZIF-8@TBAC-Lac (TBAC-Lac), Fe3O4@BC@ZIF-8@ChCl-EG (ChCl-EG), and Fe3O4@BC@ZIF-8@ChCl-Gly (ChCl-Gly) prepared in Example 6 for 4-methylmethcathinone were tested respectively (tested according to the above method). The results are as follows. Figure 8 As shown, the adsorption efficiency of Fe3O4@BC@ZIF-8@BTBAC-Lac after adding a eutectic solvent (greater than 84%) is significantly better than that of Fe3O4@BC@ZIF-8 without a eutectic solvent (approximately 76%). The adsorbent samples prepared by reacting Fe3O4@BC@ZIF-8 with different eutectic solvents show significant differences in adsorption efficiency for 4-methylmethcathinone. The sample prepared by reacting Fe3O4@BC@ZIF-8 with BTBAC-Lac eutectic solvent can achieve an adsorption efficiency of up to 98% for 4-methylmethcathinone, which is higher than that of samples prepared by reacting Fe3O4@BC@ZIF-8 with other eutectic solvents. Therefore, BTBAC-Lac eutectic solvent is preferred in this invention.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A novel adsorbent for psychoactive substances, characterized in that, The preparation method includes: (1) using activated shrimp shell biomass and Fe3O4 nanomagnetic material to react, dry and pyrolyze to obtain Fe3O4@BC; (2) mixing Fe3O4@BC and ZIF-8 to obtain Fe3O4@BC@ZIF-8; (3) mixing eutectic solvent with Fe3O4@BC@ZIF-8 to obtain a new psychoactive substance adsorbent; in step (2), the mass ratio of ZIF-8 to Fe3O4@BC is 1:(8-15); in step (3), the eutectic solvent is selected from benzyltributylammonium chloride-lactic acid, and the molar ratio of benzyltributylammonium chloride and lactic acid is 1:(2-4).

2. The novel psychoactive substance adsorbent according to claim 1, characterized in that, In step (1), the method for preparing activated shrimp shell biomass includes: mixing shrimp shell powder and KOH and dissolving them in water to activate the shrimp shell biomass, wherein the mass ratio of shrimp shell powder to KOH is 1:(1-3).

3. The novel psychoactive substance adsorbent according to claim 1 or 2, characterized in that, In step (1), the pyrolysis temperature is 500℃-700℃.

4. The novel psychoactive substance adsorbent according to claim 3, characterized in that, In step (1), the mass ratio of shrimp shell powder to KOH is 1:3, and the pyrolysis temperature is 600℃.

5. The novel psychoactive substance adsorbent according to claim 1 or 4, characterized in that, In step (2), the mass ratio of ZIF-8 to Fe3O4@BC is 1:

10.

6. The novel psychoactive substance adsorbent according to claim 1 or 4, characterized in that, In step (3), the ratio of Fe3O4@BC@ZIF-8 mass to eutectic solvent volume is 10:

1.

7. The application of the novel psychoactive substance adsorbent according to any one of claims 1 to 6 in wastewater treatment, wherein, The wastewater contains at least 4-methylcathinone.

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