Polymer-loaded modified black talc composite adsorbent and its preparation method and application

Abstract

The present invention discloses a polymer-supported modified black talc composite adsorbent and a preparation method and application thereof. Ultrafine black talc powder is purified and pretreated, then grafted and modified with an amphoteric surfactant, and finally, under the action of a crosslinking agent and an initiator, polymer monomers are combined with the successfully supported modified black talc through free radical initiation to prepare the polymer-supported modified black talc composite adsorbent. The present invention effectively utilizes the advantages of black talc, such as a large number of active sites and a unique nanosheet structure on its surface. The preparation process is simple, the raw materials are cheap and readily available, the adsorption effect is good, the production scale is easy to control, the process is green and environmentally friendly, and no secondary pollution is generated. The present invention provides a new direction for the adsorbent production field, reduces the cost of coking wastewater adsorbents, and simultaneously provides an effective and economical way to improve the comprehensive utilization of black talc ore.

Description

Technical Field

[0001] The invention relates to a preparation method and application of a polymer-loaded modified black talc composite adsorbent, and belongs to the field of comprehensive utilization of non-metallic minerals. Background Art

[0002] Coking wastewater refers to a type of chemical waste that is highly dangerous, harmful, has a large amount of wastewater, and is difficult to degrade in the coking process. Due to the rapid development of China's petrochemical, coking and other industries, the disposal of coking wastewater has also become a hot issue and a difficult problem. Because its chemical composition is quite complex and the concentration is also very high. Therefore, new treatment methods are often obtained by combining biological, physical and chemical treatment technologies. In current technology, coking wastewater is generally pre-treated with traditional technology, and then the activated sludge biological secondary treatment is carried out. However, at present, China and abroad mainly use anaerobic / aerobic process (A / O), anaerobic / anoxic / aerobic process (A 2 / O) for biological treatment. After treatment with the above technology, the cyanide and BOD indicators of the effluent can meet the discharge requirements, but the COD (mainly phenols and other difficult-to-degrade organic matter) and color are far from meeting the discharge requirements.

[0003] Therefore, further advanced treatment is necessary, and adsorption is the optimal method due to its unique advantages. Activated carbon and resin are the two most commonly used adsorbents, but activated carbon has slow adsorption kinetics, difficult desorption, and difficulty in multiple uses, which increases the cost of advanced treatment. Adsorption resins offer high stability, large adsorption capacity, and a rich pore structure, but they are also expensive and difficult to reuse. Given these shortcomings, inorganic mineral adsorption materials have garnered widespread attention in water treatment technology in recent years due to their lower cost, wide availability of raw materials, ease of manufacture, high selectivity, and ease of handling.

[0004] Black talc is a silicate clay mineral with a unique lamellar structure, specifically a TOT-type structure consisting of two silicon-oxygen tetrahedra (T) and one magnesium-oxygen octahedron (O). Black talc has no charge between its layers and exhibits excellent chemical stability. Its surface contains certain active functional groups, such as Mg-O, Si-O, and Si-OH. Mechanical crushing of the black talc exposes these surface active functional groups, creating surface active sites that impart a certain degree of adsorption to the black talc powder. However, natural black talc is highly hydrophilic and prone to hydration, making it less effective at adsorbing hydrophobic organic pollutants. Furthermore, the limited number of surface groups on black talc results in weak bonding with pollutants, making it susceptible to desorption. Therefore, methods are needed to modify black talc to make it an excellent adsorbent. Summary of the Invention

[0005] To address the high development costs and poor reproducibility of current industrial adsorbents for deep treatment of coking wastewater, the present invention provides a method for preparing a polymer-loaded modified black talc composite adsorbent for deep treatment of coking wastewater. This method utilizes polyacrylamide-loaded black talc grafted with an amphoteric surfactant as an organic adsorbent. The process is simple, and it effectively removes COD and color from biochemically treated coking wastewater. It offers advantages such as low cost, simple regeneration, and excellent reproducibility.

[0006] The technical solutions of the present invention are as follows:

[0007] In a first aspect, the present invention provides a polymer-supported modified black talc composite adsorbent, wherein the polymer-supported modified black talc composite adsorbent is prepared according to the following method:

[0008] S1: black talc powder with an average particle size of 200 to 500 nm is uniformly dispersed in deionized water, and the mixture is allowed to stand for stratification. The obtained upper layer of uniform slurry is centrifuged, and the obtained precipitate is dried, ground and dispersed to obtain purified black talc powder;

[0009] S2: uniformly dispersing the purified black talc powder described in step S1 in a surfactant aqueous solution, performing a grafting reaction at 40-90° C. for 4-10 hours (preferably 70° C. for 5 hours), and separating and washing the resulting reaction solution to obtain a grafted modified black talc powder;

[0010] The surfactants in the surfactant aqueous solution are anionic surfactants and cationic surfactants; the cationic surfactant is one or more of cetyltrimethylammonium bromide, cetyltrimethylammonium chloride, cetylpyridinium chloride, octadecyldimethylbenzyl quaternary ammonium chloride, and distearyldimethylammonium chloride (preferably cetylpyridinium chloride); the anionic surfactant is one or more of sodium dodecylbenzenesulfonate, sodium octadecanoate, sodium lauryl sulfate, sodium lauroylsarcosinate, and potassium cetyl phosphate (preferably sodium dodecylbenzenesulfonate); the concentration of the anionic surfactant in the surfactant aqueous solution is 0.25 to 0.5 mol / L (preferably 0.375 mol / L), and the concentration of the cationic surfactant is 0.25 to 0.5 mol / L (preferably 0.375 mol / L);

[0011] S3: uniformly dispersing the grafted modified black talc powder described in step S2 in deionized water A to obtain a black talc dispersion; dissolving acrylamide in deionized water B, adding an initiator and a cross-linking agent, and mixing uniformly to obtain an acrylamide solution; uniformly mixing the black talc dispersion and the acrylamide solution to obtain an aqueous phase; uniformly dispersing an oil phase organic solvent and Span80 to obtain an oil phase; adding the aqueous phase to the oil phase, and conducting a reverse phase suspension polymerization reaction at 40-90° C. for 2-10 hours (preferably 70° C. for 2 hours); and post-treating the resulting reaction solution to obtain the polymer-supported modified black talc composite adsorbent;

[0012] The oil phase organic solvent is one or more of n-hexane, cyclohexane, and n-heptane (the present invention adopts a mixed solvent of cyclohexane and n-hexane in a volume ratio of 1:1 for economic and yield considerations); the mass ratio of the acrylamide, initiator, crosslinking agent, Span80 and grafted modified black talc powder is 1:0.05-0.2:0.05-0.2:0.3-1.0:1-3 (preferably 1:0.12:0.12:0.5:2); the total volume of the deionized water A and deionized water B is 10-20 mL / g (preferably 15 mL / g) based on the mass of the acrylamide; and the volume ratio of the total volume of the deionized water A and deionized water B to the oil phase organic solvent is 1:1-5 (preferably 1:2).

[0013] In an embodiment of the present invention, the black talc powder in step S1 is prepared as follows: raw black talc ore (Guangfeng, Jiangxi) is crushed, ground, and sieved (200-300 mesh) to obtain black talc ore powder. The black talc ore powder is wet-ball milled in an ethanol aqueous solution at 500-1000 rpm for 6-18 hours. The resulting ball-milled powder is centrifuged and washed with deionized water, dried (at 60-120° C. for 10-24 hours), and ground and sieved to obtain the black talc powder. The ultrafine and uniform black talc powder has an average particle size of 200-500 nm.

[0014] Furthermore, the ethanol-water solution is prepared from anhydrous ethanol and deionized water in a volume ratio of 1 to 3:7, and the amount used is based on the amount required to immerse the black talc powder.

[0015] Furthermore, the volume of the deionized water in step S1 is 6.5 mL / g based on the mass of the black talc powder.

[0016] Furthermore, in step S2, the volume of the surfactant aqueous solution is 10-50 ml / g based on the mass of the purified black talc powder, and is 40 mL / g in one embodiment of the present invention.

[0017] Furthermore, in step S2, the separation and washing comprises: centrifuging the reaction solution, washing the obtained precipitate with deionized water, drying, grinding and sieving to obtain the graft-modified black talc powder.

[0018] Furthermore, the post-treatment in step S3 is: centrifuging the reaction solution, washing with a mixture of ethanol and water in a volume ratio of 1:1, and drying (vacuum drying to constant weight) to obtain the polymer-supported modified black talc composite adsorbent.

[0019] Those skilled in the art will appreciate that the initiator and cross-linking agent are acrylamide initiators and cross-linking agents. The initiator in step S3 is one or more of ammonium persulfate, potassium persulfate, and sodium persulfate, and in one embodiment of the present invention, is ammonium persulfate.

[0020] The cross-linking agent in step S3 is one or more of N,N-dimethylbisacrylamide, polyethylene glycol diacrylate, and epichlorohydrin. In one embodiment of the present invention, the cross-linking agent is N,N-dimethylbisacrylamide.

[0021] Furthermore, in step S3, the volume of the deionized water A is 5 to 15 mL / g (preferably 5 mL / g) based on the mass of the graft-modified black talc powder.

[0022] Furthermore, in step S3, the volume of the deionized water B is 5 to 15 mL / g (5 mL / g in one embodiment of the present invention) based on the mass of acrylamide.

[0023] In a second aspect, the present invention provides an application of a polymer-supported modified black talc composite adsorbent in adsorbing organic pollutants.

[0024] In an embodiment of the present invention, the organic pollutants are phenolic compounds, such as phenol and phenol substituted with H nitro on the benzene ring.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) The use of polyacrylamide to load modified black talc effectively increases its specific surface area and introduces a large number of nitrogen-containing functional groups, providing sufficient adsorption domains for the deep treatment of organic matter in coking wastewater.

[0027] (2) Through free radical-induced bonding, granular adsorbents are spontaneously formed, effectively avoiding the problem of mineral adsorbents being easily pulverized, causing secondary pollution, and being difficult to recycle.

[0028] (3) The preparation process is simple, the raw materials are cheap and easily available, the production scale is easy to control, it is green and environmentally friendly, and will not cause secondary pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Physical picture of ultrafine uniform black talc after ball milling;

[0030] Figure 2 Conceptual diagram of adsorbent preparation;

[0031] Figure 3 Actual photo of polymer-loaded modified black talc composite adsorbent.

[0032] Figure 4 The adsorption-desorption effect of Example 2

[0033] Figure 5 The adsorption-desorption effect of Comparative Example 6 DETAILED DESCRIPTION

[0034] The present invention will be described in detail below with reference to specific embodiments. However, the present invention is not limited to the following embodiments. Without departing from the content and scope of the present invention, any changes should be included in the technical scope of the present invention.

[0035] The adsorption rates in the following examples were tested as follows:

[0036] Prepare 200 mg / L phenol solution and tetranitrophenol solution, two phenolic organic compounds commonly found in coking wastewater, as standard adsorbate solutions, respectively. Take 50 mg of the adsorbent into 50 ml of the adsorbate solution, stir magnetically for 120 minutes, and then use a syringe to take a sample and filter it. The absorbance N0 of the original adsorbent and the absorbance N1 of the filtrate are measured by an ultraviolet spectrophotometer (the absorbance of phenol is 270 nm and the absorbance of tetranitrophenol is 317 nm). The adsorption rate Q (unit: %) of the adsorbent is calculated according to the following formula.

[0037]

[0038] Example 1:

[0039] (1) Preparation of ultrafine uniform black talc powder: Black talc from Guangfeng, Jiangxi Province was crushed, ground, and sieved (200 mesh) to obtain black talc powder. 20 mL of ethanol and 70 mL of deionized water were added to 40 g of black talc powder and placed in a ball mill for wet grinding at a speed of 700 r / min for 5 h. After the sample was removed, it was resuspended and washed with deionized water, centrifuged, and the lower layer of solid in the centrifuge tube was collected and dried at 80°C for 14 h. The solid was ground and sieved (200 mesh) to obtain ultrafine black talc powder with an average particle size of 300 nm.

[0040] (2) Pretreatment of black talc: 20 g of the ultrafine black talc powder described in step (1) was added to 130 mL of deionized water, stirred for 30 min, and allowed to stand for 6 h. The upper layer of uniform slurry was taken and centrifuged. The resulting precipitate was dried and ground to obtain pretreated black talc powder.

[0041] (3) Grafting modified black talc: 3 g of the pretreated black talc powder described in step (2) was dispersed in a mixed solution consisting of 60 mL of 0.75 mol / L chlorocetylpyridinium (CPC) aqueous solution and 60 mL of 0.75 mol / L sodium dodecylbenzenesulfonate (SDBS), reacted at 60° C. for 2 h, cooled, washed with deionized water, dried, ground and sieved (200 mesh) to obtain the grafted modified black talc powder.

[0042] (4) Polyacrylamide-loaded modified black talc: Take 1g of acrylamide and 1g of the black talc powder described in step (3) and disperse them in 5mL of deionized water, respectively, and record them as A and B; then add 0.12g of ammonium persulfate and 0.12g of N,N-dimethylbisacrylamide to A and disperse them evenly. Finally, mix A and B and disperse them evenly. Prepare the oil phase: Take 10mL of cyclohexane, 10mL of n-hexane and 0.5g of Span80 in a flask respectively, and disperse them thoroughly to make a uniform solution. Reverse suspension polymerization: Add the aqueous phase to the oil phase, react at 70℃ for 2h, then use ethanol: water = 1:1 for centrifugal washing and vacuum drying to constant weight.

[0043] (5) 0.05 g of the obtained product was weighed and used to treat 50 ml of phenol solution and tetranitrophenol solution, respectively. The adsorption effects were 71% and 82%, respectively.

[0044] Example 2:

[0045] (1) Preparation of ultrafine uniform black talc powder: Black talc from Guangfeng, Jiangxi Province was crushed, ground, and sieved (200 mesh) to obtain black talc powder. 20 mL of ethanol and 70 mL of deionized water were added to 40 g of black talc powder and placed in a ball mill for wet grinding at a speed of 700 r / min for 5 h. After the sample was removed, it was resuspended and washed with deionized water, centrifuged, and the lower layer of solid in the centrifuge tube was collected and dried at 80°C for 14 h. The solid was ground and sieved (200 mesh) to obtain ultrafine black talc powder with an average particle size of 300 nm.

[0046] (2) Pretreatment of black talc: 20 g of the ultrafine black talc powder described in step (1) was added to 130 mL of deionized water, stirred for 30 min, and allowed to stand for 6 h. The upper layer of uniform slurry was taken and centrifuged. The resulting precipitate was dried and ground to obtain pretreated black talc powder.

[0047] (3) Grafting modified black talc: 3 g of the pretreated black talc powder described in step (2) was dispersed in a mixed solution consisting of 60 mL of 0.75 mol / L chlorocetylpyridinium (CPC) aqueous solution and 60 mL of 0.75 mol / L sodium dodecylbenzenesulfonate (SDBS), reacted at 60° C. for 2 h, cooled, washed with deionized water, dried, ground and sieved (200 mesh) to obtain the grafted modified black talc powder.

[0048] (4) Polyacrylamide-loaded modified black talc: Take 1g acrylamide and 2g of the black talc powder described in step (3) and disperse them in 5mL and 10mL of deionized water respectively, and record them as A and B respectively; then add 0.12g of ammonium persulfate and 0.12g of N,N-dimethylbisacrylamide to A and disperse them evenly. Finally, mix A and B and disperse them evenly. Prepare the oil phase: Take 15mL of cyclohexane, 15mL of n-hexane and 0.5g of Span80 in a flask respectively, and disperse them thoroughly to make a uniform solution. Reverse suspension polymerization: Add the aqueous phase to the oil phase, react at 70℃ for 2h, then use ethanol: water = 1:1 for centrifugal washing and vacuum drying to constant weight.

[0049] (5) 0.05 g of the obtained product was weighed and used to treat 50 ml of phenol solution and tetranitrophenol solution, respectively. The adsorption effects were 82% and 91%, respectively.

[0050] (6) After 0.5 g of the adsorbed product was ultrasonically treated with 5% NaOH for 20 min, the desorption rate was measured to be 90%. After repeating the adsorption-desorption operation 6 times, the adsorption effect was only about 10% lower than the first adsorption effect ( Figure 1 ).

[0051] Example 3:

[0052] (1) Preparation of ultrafine uniform black talc powder: Black talc from Guangfeng, Jiangxi Province was crushed, ground, and sieved (200 mesh) to obtain black talc powder. 20 mL of ethanol and 70 mL of deionized water were added to 40 g of black talc powder and placed in a ball mill for wet grinding at a speed of 700 r / min for 5 h. After the sample was removed, it was resuspended and washed with deionized water, centrifuged, and the lower layer of solid in the centrifuge tube was collected and dried at 80°C for 14 h. The solid was ground and sieved (200 mesh) to obtain ultrafine black talc powder with an average particle size of 300 nm.

[0053] (2) Pretreatment of black talc: 20 g of the ultrafine black talc powder described in step (1) was added to 130 mL of deionized water, stirred for 30 min, and allowed to stand for 6 h. The upper layer of uniform slurry was taken and centrifuged. The resulting precipitate was dried and ground to obtain pretreated black talc powder.

[0054] (3) Grafting modified black talc: 3 g of the pretreated black talc powder described in step (2) was dispersed in a mixed solution consisting of 60 mL of 0.75 mol / L chlorocetylpyridinium (CPC) aqueous solution and 60 mL of 0.75 mol / L sodium dodecylbenzenesulfonate (SDBS), reacted at 60° C. for 2 h, cooled, washed with deionized water, dried, ground and sieved (200 mesh) to obtain the grafted modified black talc powder.

[0055] (4) Polyacrylamide-loaded modified black talc: Take 1g acrylamide and 3g of the black talc powder described in step (3) and disperse them in 5mL and 15mL of deionized water respectively, and record them as A and B respectively; then add 0.12g of ammonium persulfate and 0.12g of N,N-dimethylbisacrylamide to A and disperse them evenly. Finally, mix A and B and disperse them evenly. Prepare the oil phase: Take 20mL of cyclohexane, 20mL of n-hexane and 0.5g of Span80 in a flask respectively, and disperse them thoroughly to make a uniform solution. Reverse suspension polymerization: Add the aqueous phase to the oil phase, react at 70℃ for 2h, then use ethanol: water = 1:1 for centrifugal washing and vacuum drying to constant weight.

[0056] (5) 0.05 g of the obtained product was weighed and used to treat 50 ml of phenol solution and tetranitrophenol solution, respectively. The adsorption rates were 62% and 73%, respectively.

[0057] Comparative Example 1: No grafting

[0058] (1) Preparation of ultrafine uniform black talc powder: Black talc from Guangfeng, Jiangxi Province was crushed, ground, and sieved (200 mesh) to obtain black talc powder. 20 mL of ethanol and 70 mL of deionized water were added to 40 g of black talc powder and placed in a ball mill for wet grinding at a speed of 700 r / min for 5 h. After the sample was removed, it was resuspended and washed with deionized water, centrifuged, and the lower layer of solid in the centrifuge tube was collected and dried at 80°C for 14 h. The solid was ground and sieved (200 mesh) to obtain ultrafine black talc powder with an average particle size of 300 nm.

[0059] (2) Pretreatment of black talc: 20 g of the ultrafine black talc powder described in step (1) was added to 130 mL of deionized water, stirred for 30 min, and allowed to stand for 6 h. The upper homogeneous slurry was collected, centrifuged, dried, and ground.

[0060] (3) Polyacrylamide-loaded modified black talc: Take 1g acrylamide and 2g of the black talc powder described in step (2) and disperse them in 5mL and 10mL of deionized water respectively, and record them as A and B respectively; then add 0.12g of ammonium persulfate and 0.12g of N,N-dimethylbisacrylamide to A and disperse them evenly. Finally, mix A and B and disperse them evenly. Prepare the oil phase: Take 15mL of cyclohexane, 15mL of n-hexane and 0.5g of Span80 in a flask respectively, and disperse them thoroughly to make a uniform solution. Reverse suspension polymerization: Add the aqueous phase to the oil phase, react at 70℃ for 2h, wash with ethanol:water = 1:1, centrifuge, and vacuum dry to constant weight.

[0061] (4) 0.05 g of the obtained product was used to treat 50 ml of phenol solution and tetranitrophenol solution, respectively, and the adsorption effects were 51% and 60%.

[0062] Comparative Example 2: Polyacrylamide adsorbent

[0063] Preparation of polyacrylamide adsorbent: Prepare the aqueous phase: Disperse 2g of acrylamide in 5mL of deionized water, add 0.12g of ammonium persulfate and 0.12g of N,N-dimethylbisacrylamide, and disperse evenly. Prepare the oil phase: Disperse 5mL of cyclohexane, 5mL of n-hexane, and 0.5g of Span 80 in a flask to form a uniform solution. Reverse-phase suspension polymerization: Add the aqueous phase to the oil phase, react at 70°C for 2h, then wash with a 1:1 ethanol:water ratio, centrifuge, and vacuum dry to constant weight.

[0064] 0.05 g of the obtained product was used to treat 50 ml of phenol solution and tetranitrophenol solution, respectively, and the adsorption effects were 48% and 55%.

[0065] Comparative Example 3: No SDBS grafting

[0066] (1) Preparation of ultrafine uniform black talc powder: Black talc from Guangfeng, Jiangxi Province was crushed, ground, and sieved (200 mesh) to obtain black talc powder. 20 mL of ethanol and 70 mL of deionized water were added to 40 g of black talc powder and placed in a ball mill for wet grinding at a speed of 700 r / min for 5 h. After the sample was removed, it was resuspended and washed with deionized water, centrifuged, and the lower layer of solid in the centrifuge tube was collected and dried at 80°C for 14 h. The solid was ground and sieved (200 mesh) to obtain ultrafine black talc powder with an average particle size of 300 nm.

[0067] (2) Pretreatment of black talc: 20 g of the ultrafine black talc powder described in step (1) was added to 130 mL of deionized water, stirred for 30 min, and allowed to stand for 6 h. The upper homogeneous slurry was collected, centrifuged, dried, and ground.

[0068] (3) Grafting modified black talc: 3 g of the pretreated black talc powder described in step (2) was dispersed in 120 mL of a 0.75 mol / L chlorocetylpyridinium (CPC) aqueous solution, reacted at 60° C. for 2 h, cooled, washed, dried, ground and sieved (200 mesh) to obtain the grafted modified black talc powder.

[0069] (4) Polyacrylamide-loaded modified black talc: Take 1g acrylamide and 2g of the black talc powder described in step (3) and disperse them in 5mL and 10mL of deionized water respectively, and record them as A and B respectively; then add 0.12g of ammonium persulfate and 0.12g of N,N-dimethylbisacrylamide to A and disperse them evenly. Finally, mix A and B and disperse them evenly. Prepare the oil phase: Take 15mL of cyclohexane, 15mL of n-hexane and 0.5g of Span80 in a flask respectively, and disperse them thoroughly to make a uniform solution. Reverse suspension polymerization: Add the aqueous phase to the oil phase, react at 70℃ for 2h, wash with ethanol:water = 1:1, centrifuge, and vacuum dry to constant weight.

[0070] (5) 0.05 g of the obtained product was used to treat 50 ml of phenol solution and tetranitrophenol solution, respectively, and the adsorption effects were 54% and 65%.

[0071] Comparative Example 4: No CPC grafting

[0072] (1) Preparation of ultrafine uniform black talc powder: Black talc from Guangfeng, Jiangxi Province was crushed, ground, and sieved (200 mesh) to obtain black talc powder. 20 mL of ethanol and 70 mL of deionized water were added to 40 g of black talc powder and placed in a ball mill for wet grinding at a speed of 700 r / min for 5 h. After the sample was removed, it was resuspended and washed with deionized water, centrifuged, and the lower layer of solid in the centrifuge tube was collected and dried at 80°C for 14 h. The solid was ground and sieved (200 mesh) to obtain ultrafine black talc powder with an average particle size of 300 nm.

[0073] (2) Pretreatment of black talc: 20 g of the ultrafine black talc powder described in step (1) was added to 130 mL of deionized water, stirred for 30 min, and allowed to stand for 6 h. The upper homogeneous slurry was collected, centrifuged, dried, and ground.

[0074] (3) Grafting modified black talc: 3 g of the pretreated black talc powder described in step (2) was dispersed in 120 mL of a 0.75 mol / L sodium dodecylbenzenesulfonate (SDBS) aqueous solution, reacted at 60° C. for 2 h, cooled, washed, dried, ground and sieved (200 mesh) to obtain the grafted modified black talc powder.

[0075] (4) Polyacrylamide-loaded modified black talc: Take 1g acrylamide and 2g of the black talc powder described in step (3) and disperse them in 5mL and 10mL of deionized water respectively, and record them as A and B respectively; then add 0.12g of ammonium persulfate and 0.12g of N,N-dimethylbisacrylamide to A and disperse them evenly. Finally, mix A and B and disperse them evenly. Prepare the oil phase: Take 15mL of cyclohexane, 15mL of n-hexane and 0.5g of Span80 in a flask respectively, and disperse them thoroughly to make a uniform solution. Reverse suspension polymerization: Add the aqueous phase to the oil phase, react at 70℃ for 2h, wash with ethanol:water = 1:1, centrifuge, and vacuum dry to constant weight.

[0076] (5) 0.05 g of the obtained product was used to treat 50 ml of phenol solution and tetranitrophenol solution, respectively, and the adsorption effects were 51% and 59%.

[0077] Comparative Example 5: Sepiolite adsorbent

[0078] (1) Pretreatment of sepiolite: 20 g of ultrafine sepiolite powder (300 mesh) purchased from Hebei Hongyao Mining Company was added to 130 mL of deionized water, stirred for 30 min, and allowed to stand for 6 h. The upper layer of uniform slurry was taken and centrifuged. The resulting precipitate was dried and ground to obtain pretreated sepiolite powder (200 mesh).

[0079] (2) Graft modification of sepiolite: 3 g of the pretreated sepiolite powder described in step (2) was dispersed in a mixed solution consisting of 60 mL of a 0.75 mol / L aqueous solution of cetylpyridinium chloride (CPC) and 60 mL of 0.75 mol / L sodium dodecylbenzenesulfonate (SDBS), reacted at 60° C. for 2 h, cooled, washed with deionized water, dried, ground and sieved (200 mesh) to obtain the graft modified sepiolite powder.

[0080] (3) Modified sepiolite loaded with polyacrylamide: 1 g acrylamide and 2 g of the sepiolite powder described in step (2) were dispersed in 5 mL and 10 mL of deionized water, respectively, and were denoted as A and B; 0.12 g of ammonium persulfate and 0.12 g of N,N-dimethylbisacrylamide were then added to A and dispersed evenly, and finally A and B were mixed and dispersed evenly. Preparation of oil phase: 15 mL of cyclohexane, 15 mL of n-hexane and 0.5 g of Span80 were taken in a flask and fully dispersed to form a uniform solution. Reverse phase suspension polymerization: The aqueous phase was added to the oil phase, reacted at 70°C for 2 h, and then centrifuged and washed with ethanol: water = 1:1 and vacuum dried to constant weight.

[0081] (4) 0.05 g of the obtained product was weighed and used to treat 50 ml of phenol solution and tetranitrophenol solution, respectively. The adsorption effects were 70% and 84%, respectively, which were poorer than those in Example 2.

[0082] Comparative Example 6:

[0083] Polyacrylamide organically modified black talc: Weigh 10g of the ultrafine black talc powder prepared according to Example 1 and react with 100ml of 6mol / L hydrochloric acid at 25°C for 6h, then wash, filter, and dry. Thermally modify the mixture in a muffle furnace at 250°C for 2h, then cool to room temperature. Next, inorganically modify 5g of the acid-activated black talc by immersing it in 100ml of 0.3mol / L AlCl3 solution at 70°C for 1h. After aging at room temperature for 24h, rinse, filter, and dry. Finally, add 2g of the modified black talc to 100mL of 12g / L polyacrylamide solution, stir at room temperature for 3h, age for 24h, wash, filter, and dry. The resulting filter cake is dried, ground, and set aside.

[0084] 0.05 g of the obtained product was weighed and used to treat 50 ml of phenol solution and tetranitrophenol solution, respectively, and the adsorption effects were 69% and 88%.

[0085] After 0.5g of the adsorbed product was ultrasonically treated with 5% NaOH for 20min, the desorption rate was measured to be 81%. After repeated use for 2 times, the adsorption effect was only about 30% of the first adsorption effect ( Figure 5 ).

[0086] Comparative Example 7: Oil phase Tween 40

[0087] (1) Preparation of ultrafine uniform black talc powder: Black talc from Guangfeng, Jiangxi Province was crushed, ground, and sieved (200 mesh) to obtain black talc powder. 20 mL of ethanol and 70 mL of deionized water were added to 40 g of black talc powder and placed in a ball mill for wet grinding at a speed of 700 r / min for 5 h. After the sample was removed, it was resuspended and washed with deionized water, centrifuged, and the lower layer of solid in the centrifuge tube was collected and dried at 80°C for 14 h. The solid was ground and sieved (200 mesh) to obtain ultrafine black talc powder with an average particle size of 300 nm.

[0088] (2) Pretreatment of black talc: 20 g of the ultrafine black talc powder described in step (1) was added to 130 mL of deionized water, stirred for 30 min, and allowed to stand for 6 h. The upper layer of uniform slurry was taken and centrifuged. The resulting precipitate was dried and ground to obtain pretreated black talc powder.

[0089] (3) Grafting modified black talc: 3 g of the pretreated black talc powder described in step (2) was dispersed in a mixed solution consisting of 60 mL of 0.75 mol / L chlorocetylpyridinium (CPC) aqueous solution and 60 mL of 0.75 mol / L sodium dodecylbenzenesulfonate (SDBS), reacted at 60° C. for 2 h, cooled, washed with deionized water, dried, ground and sieved (200 mesh) to obtain the grafted modified black talc powder.

[0090] (4) Polyacrylamide-loaded modified black talc: 1 g acrylamide and 2 g black talc powder from step (3) were dispersed in 5 mL and 10 mL deionized water, respectively, and were designated as A and B; 0.12 g ammonium persulfate and 0.12 g N,N-dimethylbisacrylamide were then added to A and dispersed evenly, and finally A and B were mixed and dispersed evenly. Preparation of the oil phase: 15 mL cyclohexane, 15 mL n-hexane, and 0.5 g Tween40 were respectively added to a flask and dispersed thoroughly to form a uniform solution. Reverse phase suspension polymerization: The aqueous phase was added to the oil phase, reacted at 70°C for 2 h, and then centrifuged and washed with ethanol:water = 1:1 and vacuum dried to constant weight.

[0091] Compared with Example 2, the adsorbent polymerized with Tween-40 has non-uniform particle size and uneven dispersion of black talc.

[0092] 0.05 g of the obtained product was weighed and used to treat 50 ml of phenol solution and tetranitrophenol solution, respectively. The adsorption effects were 53% and 61%, respectively, which were poorer than those in Example 2.

[0093] Comparative Example 8: Oil Phase Sodium Oleate

[0094] (1) Preparation of ultrafine uniform black talc powder: Black talc from Guangfeng, Jiangxi Province was crushed, ground, and sieved (200 mesh) to obtain black talc powder. 20 mL of ethanol and 70 mL of deionized water were added to 40 g of black talc powder and placed in a ball mill for wet grinding at a speed of 700 r / min for 5 h. After the sample was removed, it was resuspended and washed with deionized water, centrifuged, and the lower layer of solid in the centrifuge tube was collected and dried at 80°C for 14 h. The solid was ground and sieved (200 mesh) to obtain ultrafine black talc powder with an average particle size of 300 nm.

[0095] (2) Pretreatment of black talc: 20 g of the ultrafine black talc powder described in step (1) was added to 130 mL of deionized water, stirred for 30 min, and allowed to stand for 6 h. The upper layer of uniform slurry was taken and centrifuged. The resulting precipitate was dried and ground to obtain pretreated black talc powder.

[0096] (3) Grafting modified black talc: 3 g of the pretreated black talc powder described in step (2) was dispersed in a mixed solution consisting of 60 mL of 0.75 mol / L chlorocetylpyridinium (CPC) aqueous solution and 60 mL of 0.75 mol / L sodium dodecylbenzenesulfonate (SDBS), reacted at 60° C. for 2 h, cooled, washed with deionized water, dried, ground and sieved (200 mesh) to obtain the grafted modified black talc powder.

[0097] (4) Polyacrylamide-loaded modified black talc: Take 1g acrylamide and 2g of the black talc powder described in step (3) and disperse them in 5mL and 10mL of deionized water respectively, and record them as A and B respectively; then add 0.12g of ammonium persulfate and 0.12g of N,N-dimethylbisacrylamide to A and disperse them evenly. Finally, mix A and B and disperse them evenly. Prepare the oil phase: Take 15mL of cyclohexane, 15mL of n-hexane and 0.5g of sodium oleate in a flask respectively, and disperse them thoroughly to make a uniform solution. Reverse suspension polymerization: Add the aqueous phase to the oil phase, react at 70℃ for 2h, then use ethanol: water = 1:1 for centrifugal washing and vacuum drying to constant weight.

[0098] Compared with Example 2, the adsorbent polymerized from sodium oleate has an uneven particle size and poor dispersion effect.

[0099] 0.05 g of the obtained product was weighed and used to treat 50 ml of phenol solution and tetranitrophenol solution, respectively. The adsorption effects were 57% and 66%, respectively, which were poorer than those in Example 2.

Claims

1. A polymer-supported modified black talc composite adsorbent, characterized in that The polymer-supported modified black talc composite adsorbent is prepared according to the following method: S1: black talc powder with an average particle size of 200 to 500 nm is uniformly dispersed in deionized water, and the mixture is allowed to stand for stratification. The obtained upper layer of uniform slurry is centrifuged, and the obtained precipitate is dried, ground and dispersed to obtain purified black talc powder; S2: uniformly dispersing the purified black talc powder described in step S1 in a surfactant aqueous solution, performing a grafting reaction at 40-90° C. for 4-10 hours, and separating and washing the resulting reaction solution to obtain a grafted modified black talc powder; The surfactants in the surfactant aqueous solution are anionic surfactants and cationic surfactants; the cationic surfactant is one or more of cetyltrimethylammonium bromide, cetyltrimethylammonium chloride, cetylpyridinium chloride, octadecyldimethylbenzyl quaternary ammonium chloride and distearyldimethylammonium chloride; the anionic surfactant is one or more of sodium dodecylbenzenesulfonate, sodium octadecanoate, sodium lauryl sulfate, sodium lauroyl sarcosinate and potassium cetyl phosphate; the concentration of the anionic surfactant in the surfactant aqueous solution is 0.25 to 0.5 mol / L, and the concentration of the cationic surfactant is 0.25 to 0.5 mol / L; S3: uniformly dispersing the grafted modified black talc powder described in step S2 in deionized water A to obtain a black talc dispersion; dissolving acrylamide in deionized water B, adding an initiator and a cross-linking agent, and mixing uniformly to obtain an acrylamide solution; uniformly mixing the black talc dispersion and the acrylamide solution to obtain an aqueous phase; uniformly dispersing an oil phase organic solvent and Span80 to obtain an oil phase; adding the aqueous phase to the oil phase, and conducting a reverse phase suspension polymerization reaction at 40-90° C. for 2-10 hours. The obtained reaction solution is post-treated to obtain the polymer-supported modified black talc composite adsorbent; The oil phase organic solvent is one or more of n-hexane, cyclohexane, and n-heptane; the mass ratio of the acrylamide, initiator, crosslinker, Span80, and grafted modified black talc powder is 1:0.05-0.2:0.05-0.2:0.3-1.0:1-3; the total volume of the deionized water A and deionized water B is 10-20 mL / g based on the mass of the acrylamide; and the volume ratio of the total volume of the deionized water A and deionized water B to the oil phase organic solvent is 1:1-5.

2. The polymer-supported modified black talc composite adsorbent according to claim 1, characterized in that: The volume of the deionized water in step S1 is 6.5 mL / g based on the mass of the black talc powder.

3. The polymer-supported modified black talc composite adsorbent according to claim 1, characterized in that: In step S2, the volume of the surfactant aqueous solution is 10 to 50 mL / g based on the mass of the purified black talc powder.

4. The polymer-supported modified black talc composite adsorbent according to claim 1, characterized in that: In step S2, the separation and washing comprises: centrifuging the reaction solution, washing the obtained precipitate with deionized water, drying, grinding and sieving to obtain the graft-modified black talc powder.

5. The polymer-supported modified black talc composite adsorbent according to claim 1, characterized in that: In step S2, the cationic surfactant is cetylpyridinium chloride.

6. The polymer-supported modified black talc composite adsorbent according to claim 1, characterized in that: In step S2, the anionic surfactant is sodium dodecylbenzenesulfonate.

7. The polymer-supported modified black talc composite adsorbent according to claim 1, characterized in that: The post-treatment in step S3 is: centrifuging the reaction solution, washing with a mixture of ethanol and water in a volume ratio of 1:1, and drying to obtain the polymer-supported modified black talc composite adsorbent.

8. The polymer-supported modified black talc composite adsorbent according to claim 1, characterized in that: The initiator in step S3 is one or more of ammonium persulfate, potassium persulfate, and sodium persulfate; The cross-linking agent in step S3 is one or more of N,N-dimethylbisacrylamide, polyethylene glycol diacrylate, and epichlorohydrin.

9. Use of the polymer-supported modified black talc composite adsorbent according to any one of claims 1 to 8 in adsorbing organic pollutants.

10. The use according to claim 9, characterized in that: The organic pollutants are phenol compounds.

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