A high-performance composite bentonite and its preparation method

Abstract

The present invention belongs to the technical field of material preparation, and relates to a high-performance composite bentonite and a preparation method thereof; the components by weight include: 80-100 parts of modified bentonite; 2-5 parts of modified zirconia; 10-15 parts of vermiculite; 15-20 parts of diatomite. The modified bentonite is acidified sodium bentonite, with an increased specific surface area, which is more conducive to cation exchange and improved adsorption effect; the modified zirconia is yttrium-stabilized zirconia supported on porous carbon material. On the surface of the modified zirconia, phosphate adsorbs with the modified zirconia particles to form a complex. The porous structure of the carbon material increases the specific surface area, making it easier to exchange with heavy metal ions, and pollutant molecules can better enter the porous carbon structure and are more easily adsorbed. The present invention improves the sewage treatment ability of bentonite by modifying bentonite and adding modified zirconia, and the product quality is significantly improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of material preparation, and specifically refers to a high-performance composite bentonite and a preparation method thereof. Background Art

[0002] Bentonite is a water-containing clay mineral with montmorillonite as the main mineral component. Due to its special properties such as swelling, adhesiveness, adsorption, catalysis, and cation exchangeability, bentonite is widely used in various industrial fields and is called the "universal soil" by people.

[0003] Sewage refers to the discharged water polluted to a certain extent from life and production. There are a large number of pollutants in sewage, including suspended solids containing insoluble substances, heavy metal ions, inorganic salts, etc. The main pollutants are phosphorus elements and heavy metal ions such as cadmium and lead. The enrichment of phosphorus elements in water will lead to eutrophication of water bodies and deterioration of water quality; the enrichment of heavy metal elements will lead to deterioration of soil quality and, if absorbed by the human body, will cause great harm to human health; bentonite has strong cation exchange ability and adsorption property, and has a certain adsorption ability for various ions, liquids, and organic substances, and the maximum adsorption capacity can reach 5 times its own weight. Therefore, bentonite is widely used in sewage treatment.

[0004] Currently, the existing technologies mainly have the following problems:

[0005] 1. The removal rate of pollutants by single bentonite is not high, and it is difficult to adapt to the deteriorating sewage environment;

[0006] 2. The adsorption rate of single bentonite is too slow, the sewage treatment effect is not ideal, and the sewage treatment capacity needs to be improved to meet the actual needs. Summary of the Invention

[0007] In view of the above situation, in order to overcome the defects of the existing technologies, the present invention provides a preparation method of a high-performance composite bentonite, which solves the problem of insufficient adsorption capacity of bentonite and realizes the technical effect of improving the sewage treatment effect of bentonite.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is as follows: The present invention provides a high-performance composite bentonite, which comprises the following components in parts by weight: 80-100 parts of modified bentonite; 2-5 parts of modified zirconia; 10-15 parts of vermiculite; 15-20 parts of diatomite.

[0009] Preferably, the modified bentonite is acidified sodium bentonite, and the specific preparation method comprises the following steps:

[0010] 【1】. Subject the calcium bentonite to water bath heating and drying with Na2CO3 solution to obtain sodium bentonite;

[0011] 【2】Mix sodium bentonite and sulfuric acid, heat under reflux, centrifuge, wash, ultrasonicate, and dry to obtain acidified sodium bentonite.

[0012] Preferably, in step 【1】, the mass-to-volume ratio of calcareous bentonite to Na2CO3 solution is 1:2, the mass concentration of the Na2CO3 solution is 4%, the water bath heating temperature is 70°C, and the heating time is 1 h.

[0013] Preferably, in step 【2】, the mass-to-volume ratio of sodium bentonite to sulfuric acid is 1:4, the mass concentration of sulfuric acid is 10%, the reflux heating temperature is 70°C, the reflux time is 6 h, the centrifugation speed is 3000 r / min, the centrifugation time is 0.5 h, ultrasonicate at a power of 500 W for 0.5 h, the drying temperature is 100 - 110°C, and the drying time is 8 h.

[0014] Preferably, the modified zirconia is yttrium-stabilized zirconia supported on a porous carbon material. The specific preparation method includes the following steps:

[0015] (1) Mix ZrOCl2·8H2O, YCl3·6H2O, and urea, perform hydrothermal treatment, dry, calcine, ball mill, and dry to obtain yttrium-stabilized zirconia.

[0016] (2) Dissolve zinc nitrate hexahydrate and 2-methylimidazole in ethanol respectively, ultrasonicate to obtain a clear solution, mix, ensure the mixed solution is clear and transparent, heat under reflux, stir, separate and collect the precipitate, wash, dry under vacuum, calcine and hold to obtain a porous carbon material.

[0017] (3) Disperse the porous carbon material and yttrium-stabilized zirconia in a beaker, ultrasonicate and stir, adjust the pH, perform hydrothermal treatment, and after drying and grinding, obtain the modified zirconia.

[0018] Preferably, in step (1), the molar ratio of ZrOCl2·8H2O to YCl3·6H2O is 1:1, the molar ratio of ZrOCl2·8H2O to urea is 1:1.2, the hydrothermal treatment temperature is 220°C, the pressure is 7 MPa, the treatment time is 5 h, the drying temperature is 120°C, the drying time is 10 h, the calcination temperature is 800 - 900°C, and the calcination time is 1 h.

[0019] Preferably, in step (1), the ball mill is a variable-frequency planetary ball mill, the ball milling medium is high-aluminum balls, the water-to-ball-to-material ratio is 6:2:1, the grinding time is 12 h, the ball mill speed is 400 r / min, the drying temperature is 120°C, and the drying time is 10 h.

[0020] Preferably, in step (2), the mass-to-volume ratio of zinc nitrate hexahydrate to ethanol is 1:42, the mass-to-volume ratio of 2-methylimidazole to ethanol is 1:16, ultrasonic treatment is carried out at a power of 300 W to 500 W for 0.5 h, the reflux heating temperature is 65 °C, the reaction is carried out for 1 h, washed with ethanol three times, vacuum dried at 70 °C for 12 h, the calcination temperature is 800 °C to 900 °C, and the calcination is carried out under inert gas protection for 2 h;

[0021] Preferably, in step (3), the mass ratio of the porous carbon material to yttria-stabilized zirconia is 1:4, and dispersed for 1.5 h under the condition of an ultrasonic power of 400 W to 800 W, and the pH is adjusted to 10 with 1 mol / L NaOH solution;

[0022] Preferably, in step (3), the hydrothermal treatment temperature is 200 °C, the treatment duration is 0.5 h, and the drying temperature is 100 to 110 °C.

[0023] The present invention also provides a high-performance composite bentonite and a preparation method thereof, which specifically include the following steps:

[0024] S1. Grind the modified bentonite, diatomite, and vermiculite into powders and mix them to obtain a mixed powder;

[0025] S2. Mix the above-mentioned mixed powder with modified zirconia, add water and stir, dry and grind into powder to obtain the high-performance composite bentonite.

[0026] Preferably, in S1, grind and crush into 400-mesh powder;

[0027] Preferably, in S2, the temperature of water is 80 °C, the solid-liquid mass-to-volume ratio is 1:3, and the stirring duration is 0.5 h;

[0028] Preferably, in S2, the drying temperature is 100 to 110 °C, and grind and crush into 200-mesh powder.

[0029] The beneficial effects obtained by the present invention are as follows:

[0030] The high-performance composite bentonite prepared by the present invention enhances the decontamination ability of bentonite by modifying bentonite and adding modified zirconia, resulting in a high pollutant removal rate and fast adsorption rate of bentonite, achieving the technical effect of stronger sewage treatment ability of bentonite; the modified bentonite is sodium-acidified bentonite, and sodium ions are more conducive to cation exchange. The specific surface area of the acidified bentonite increases, and the adsorption effect is improved; the modified zirconia can adsorb phosphate to form surface complexes. The tetravalent zirconium in the modified zirconia has chemical affinity with sulfate ions, and the modified zirconia has good adsorption ability for phosphate ions and sulfate ions; zirconia particles in the hydrated form can undergo ligand exchange with heavy metal ions. Using porous carbon materials as carriers increases the specific surface area, making it easier to exchange with heavy metal ions. Pollutant molecules can better enter the porous carbon structure, enabling pollutants to be adsorbed onto the surface of the carbon material; vermiculite and diatomite have a relatively large specific surface area, good interlayer cation exchange ability and adsorption ability, and can associate with colloidal particles and polar molecules in sewage on the surface to form aggregates for easy separation, further enhancing the sewage treatment ability of bentonite. Brief Description of the Drawings

[0031] Figure 1 is the adsorption result diagram of acid radical ions;

[0032] Figure 2 is the adsorption result diagram of heavy metal ions;

[0033] Figure 3 is the adsorption time result diagram of the maximum adsorption amount of acid radical ions;

[0034] Figure 4 is the adsorption time result diagram of the maximum adsorption amount of heavy metal ions;

[0035] Figure 5 is the scanning electron microscope result diagram of the high-performance composite bentonite;

[0036] The drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the present invention and do not constitute a limitation to the present invention. Detailed Embodiments

[0037] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

[0038] Unless otherwise defined, all professional and scientific terms used herein have the same meaning as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to those described can be applied to the present invention. The preferred methods and materials described herein are for illustrative purposes only and do not limit the content of this application.

[0039] In the following examples, the experimental methods are conventional methods unless otherwise specified; the test materials used in the following examples are obtained from commercial channels unless otherwise specified.

[0040] Calcium bentonite CasNo: 1302-78-9, purchased from Beijing Innochem Science & Technology Co., Ltd., product number I09360;

[0041] Na2CO3 solution CasNo: 497-19-8, purchased from Beijing Innochem Science & Technology Co., Ltd., product number A19943;

[0042] Sulfuric acid CasNo: 7664-93-9, purchased from Beijing Wokai Biotechnology Co., Ltd., product number 124230025;

[0043] ZrOCl2·8H2O CasNo: 13520-92-8, purchased from Beijing Wokai Biotechnology Co., Ltd., product number 208370050;

[0044] YCl3·6H2O CasNo: 10025-94-2, purchased from Beijing Wokai Biotechnology Co., Ltd., product number 199180500;

[0045] Urea CasNo: 57-13-6, purchased from Beijing Innochem Science & Technology Co., Ltd., product number B76892;

[0046] Zinc nitrate hexahydrate CasNo: 10196-18-6, purchased from Beijing Wokai Biotechnology Co., Ltd., product number 211660050;

[0047] Ethanol CasNo: 64-17-5, purchased from Beijing Innochem Science & Technology Co., Ltd., product number G00004;

[0048] 2-Methylimidazole CasNo: 693-98-1, purchased from Beijing Innochem Science & Technology Co., Ltd., product number A50320;

[0049] NaOH solution CasNo: 1310-73-2, purchased from Beijing Innochem Science & Technology Co., Ltd., product number A53741;

[0050] Vermiculite CasNo: 1318-00-9, purchased from Shanghai Macklin Biochemical Co., Ltd., product number V885843-1kg;

[0051] Diatomaceous earth, CasNo: 68855-54-9, purchased from Beijing Innochem Science & Technology Co., Ltd., product number B42396.

[0052] Example 1

[0053] A high-performance composite bentonite, comprising the following components in parts by weight: 80 parts of modified bentonite; 2 parts of modified zirconia; 10 parts of vermiculite; 15 parts of diatomaceous earth.

[0054] A preparation method of the high-performance composite bentonite specifically comprises the following steps:

[0055] S1. Grind 80 parts by weight of modified bentonite, 15 parts by weight of diatomaceous earth, and 10 parts by weight of vermiculite into 400-mesh powder, and mix to obtain a mixed powder;

[0056] S2. Add 2 parts by weight of modified zirconia to the obtained mixed powder, stir and mix evenly, add water at 80°C and stir to ensure that the solid-liquid mass-volume ratio is 1:3, stir for 0.5 h, dry at 110°C, and grind and crush into 200-mesh powder to obtain the high-performance composite bentonite.

[0057] The modified bentonite is acidified sodium bentonite, and the specific preparation method comprises the following steps:

[0058] 【1】. Mix calcium bentonite and a 4% Na2CO3 solution by mass volume ratio of 1:2, carry out water bath heating at 70°C for 1 h, and dry to obtain sodium bentonite;

[0059] 【2】. Mix sodium bentonite and a 10% sulfuric acid by mass volume ratio of 1:4 in a flask, carry out reflux heating at 70°C for 6 h, carry out centrifugation treatment at a rotation speed of 3000 r / min for 0.5 h, wash, carry out ultrasonic treatment at a power of 500 W for 0.5 h, and dry at 100°C for 8 h to obtain acidified sodium bentonite.

[0060] The modified zirconia is yttrium-stabilized zirconia supported on a porous carbon material, and the specific preparation method comprises the following steps:

[0061] (1) Mix ZrOCl2·8H2O, YCl3·6H2O and urea, the molar ratio of ZrOCl2·8H2O to YCl3·6H2O is 1:1, the molar ratio of ZrOCl2·8H2O to urea is 1:1.2, carry out hydrothermal treatment at 220°C and 7 MPa for 5 h, dry at 120°C for 10 h, calcine at 800°C for 1 h, use a variable-frequency planetary ball mill and high-aluminum ball milling medium, carry out ball milling for 12 h under the conditions of a water-ball material ratio of 6:2:1 and a ball mill rotation speed of 400 r / min, and dry at 120°C for 10 h to obtain yttrium-stabilized zirconia;

[0062] (2) Dissolve zinc nitrate hexahydrate and 2-methylimidazole in ethanol respectively. The mass-volume ratio of zinc nitrate hexahydrate to ethanol is 1:42, and the mass-volume ratio of 2-methylimidazole to ethanol is 1:16. Perform ultrasonic treatment at a power of 300 W for 0.5 h to obtain a clear solution. Mix them, reflux and heat at 65 °C for 1 h, stir, separate and collect the precipitate, wash it 3 times with ethanol, dry it in vacuum at 70 °C for 12 h, and calcine it at 800 °C under the protection of inert gas for 2 h to obtain a porous carbon material.

[0063] (3) Disperse the porous carbon material and yttrium-stabilized zirconia in a beaker. The mass ratio of the porous carbon material to yttrium-stabilized zirconia is 1:4. Perform ultrasonic treatment at a power of 400 W for 1.5 h, stir, adjust the pH to 10 with 1 mol / L NaOH solution, perform hydrothermal treatment at 200 °C for 0.5 h, dry it at 100 °C and grind it to obtain modified zirconia.

[0064] Example 2

[0065] A high-performance composite bentonite, comprising the following components in parts by weight: 100 parts of modified bentonite; 2 parts of modified zirconia; 10 parts of vermiculite; 15 parts of diatomite.

[0066] A preparation method of a high-performance composite bentonite specifically includes the following steps:

[0067] S1. Grind 100 parts by weight of modified bentonite, 15 parts by weight of diatomite, and 10 parts by weight of vermiculite into 400-mesh powder, and mix them to obtain a mixed powder.

[0068] S2. Add 2 parts by weight of modified zirconia to the obtained mixed powder, stir and mix evenly, add water at 80 °C and stir to ensure that the solid-liquid mass-volume ratio is 1:3, stir for 0.5 h, dry at 110 °C and grind it into 200-mesh powder to obtain the high-performance composite bentonite.

[0069] The modified bentonite is acidified sodium bentonite, and its specific preparation method includes the following steps:

[0070] 【1】. Mix calcium bentonite and 4% Na2CO3 solution by mass-volume ratio of 1:2, perform water bath heating at 70 °C for 1 h, and dry to obtain sodium bentonite.

[0071] 【2】. Mix sodium bentonite and 10% sulfuric acid by mass-volume ratio of 1:4 in a flask, reflux and heat at 70 °C for 6 h, perform centrifugation at a rotation speed of 3000 r / min for 0.5 h, wash, perform ultrasonic treatment at a power of 500 W for 0.5 h, and dry at 110 °C for 8 h to obtain acidified sodium bentonite.

[0072] The modified zirconia is yttrium-stabilized zirconia supported on a porous carbon material, and the specific preparation method includes the following steps:

[0073] (1) Mix ZrOCl2·8H2O, YCl3·6H2O and urea. The molar ratio of ZrOCl2·8H2O to YCl3·6H2O is 1:1, and the molar ratio of ZrOCl2·8H2O to urea is 1:1.2. Hydrothermally treat at 220°C and 7 MPa for 5 h, dry at 120°C for 10 h, calcine at 800°C for 1 h. Use a variable-frequency planetary ball mill with high-aluminum ball milling media, and ball mill for 12 h under the conditions of a water-ball-material ratio of 6:2:1 and a ball mill rotation speed of 400 r / min. Dry at 120°C for 10 h to obtain yttrium-stabilized zirconia;

[0074] (2) Dissolve zinc nitrate hexahydrate and 2-methylimidazole in ethanol respectively. The mass-volume ratio of zinc nitrate hexahydrate to ethanol is 1:42, and the mass-volume ratio of 2-methylimidazole to ethanol is 1:16. Perform ultrasonic treatment at a power of 300 W for 0.5 h to obtain a clear solution. Mix them, reflux and heat at 65°C for 1 h, stir, separate and collect the precipitate, wash it 3 times with ethanol, dry it under vacuum at 70°C for 12 h, and calcine it at 900°C under inert gas protection for 2 h to obtain a porous carbon material.

[0075] (3) Disperse the porous carbon material and yttrium-stabilized zirconia in a beaker. The mass ratio of the porous carbon material to yttrium-stabilized zirconia is 1:4. Ultrasonic at a power of 800 W for 1.5 h, stir, adjust the pH to 10 with 1 mol / L NaOH solution, hydrothermally treat at 200°C for 0.5 h, dry at 110°C, grind and pulverize to obtain modified zirconia.

[0076] Example 3

[0077] A high-performance composite bentonite, comprising the following components in parts by weight: 100 parts of modified bentonite; 3 parts of modified zirconia; 15 parts of vermiculite; 15 parts of diatomite.

[0078] A preparation method of a high-performance composite bentonite specifically includes the following steps:

[0079] S1. Grind 80 parts by weight of modified bentonite, 15 parts by weight of diatomite, and 10 parts by weight of vermiculite into 400-mesh powder, and mix to obtain a mixed powder;

[0080] S2. Add 2 parts by weight of modified zirconia to the obtained mixed powder, stir and mix evenly, add water at 80°C and stir to ensure a solid-liquid mass-volume ratio of 1:3, stir for 0.5 h, dry at 110°C, grind and pulverize into 200-mesh powder to obtain the high-performance composite bentonite.

[0081] The modified bentonite is acidified sodium bentonite, and the specific preparation method includes the following steps:

[0082] 【1】 Mix calcium bentonite with a 4% Na2CO3 solution by a mass-to-volume ratio of 1:2, carry out water bath heating at 70 °C for 1 h, and dry to obtain sodium bentonite;

[0083] 【2】 Mix sodium bentonite and 10% sulfuric acid by a mass-to-volume ratio of 1:4 in a flask, reflux and heat at 70 °C for 6 h, carry out centrifugation at a rotation speed of 3000 r / min for 0.5 h, wash, carry out ultrasonic treatment at a power of 500 W for 0.5 h, and dry at 100 °C for 8 h to obtain acidified sodium bentonite.

[0084] The modified zirconia is yttrium-stabilized zirconia supported on a porous carbon material, and the specific preparation method includes the following steps:

[0085] (1) Mix ZrOCl2·8H2O, YCl3·6H2O and urea, with a molar ratio of ZrOCl2·8H2O to YCl3·6H2O of 1:1 and a molar ratio of ZrOCl2·8H2O to urea of 1:1.2, carry out hydrothermal treatment at 220 °C and 7 MPa for 5 h, dry at 120 °C for 10 h, calcine at 800 °C for 1 h, use a variable-frequency planetary ball mill and high-aluminum ball milling media, carry out ball milling for 12 h under the conditions of a water-to-ball ratio of 6:2:1 and a ball mill rotation speed of 400 r / min, and dry at 120 °C for 10 h to obtain yttrium-stabilized zirconia;

[0086] (2) Dissolve zinc nitrate hexahydrate and 2-methylimidazole in ethanol respectively, with a mass-to-volume ratio of zinc nitrate hexahydrate to ethanol of 1:42 and a mass-to-volume ratio of 2-methylimidazole to ethanol of 1:16, carry out ultrasonic treatment at a power of 500 W for 0.5 h to obtain a clear solution, mix, reflux and heat at 65 °C for 1 h, stir, separate and collect the precipitate, wash 3 times with ethanol, vacuum dry at 70 °C for 12 h, calcine under inert gas protection at 900 °C, and keep the temperature for 2 h to obtain a porous carbon material.

[0087] (3) Disperse the porous carbon material and yttrium-stabilized zirconia in a beaker, with a mass ratio of the porous carbon material to yttrium-stabilized zirconia of 1:4, carry out ultrasonic treatment at a power of 600 W for 1.5 h, stir, adjust the pH to 10 with 1 mol / L NaOH solution, carry out hydrothermal treatment at 200 °C for 0.5 h, and after drying and grinding at 100 °C, obtain modified zirconia.

[0088] Example 4

[0089] A high-performance composite bentonite includes the following components in parts by weight: 100 parts of modified bentonite; 5 parts of modified zirconia; 15 parts of vermiculite; 20 parts of diatomite.

[0090] A preparation method of a high-performance composite bentonite, specifically including the following steps:

[0091] S1. Grind 80 parts by weight of modified bentonite, 15 parts by weight of diatomite, and 10 parts by weight of vermiculite into 400-mesh powder, and mix to obtain a mixed powder;

[0092] S2. Add 2 parts by weight of modified zirconia to the above-obtained mixed powder, stir and mix evenly, add water at 80°C and stir to ensure that the solid-liquid mass-volume ratio is 1:3, stir for 0.5 h, dry at 110°C, and grind and crush into 200-mesh powder to obtain the high-performance composite bentonite.

[0093] The modified bentonite is acidified sodium bentonite, and the specific preparation method includes the following steps:

[0094] 【1】. Mix calcium bentonite and a 4% Na2CO3 solution by mass-volume ratio of 1:2, carry out water bath heating at 70°C for 1 h, and dry to obtain sodium bentonite;

[0095] 【2】. Mix sodium bentonite and 10% sulfuric acid by mass-volume ratio of 1:4 in a flask, carry out reflux heating at 70°C for 6 h, carry out centrifugation at a rotation speed of 3000 r / min for 0.5 h, wash, carry out ultrasonic treatment at a power of 500 W for 0.5 h, and dry at 110°C for 8 h to obtain acidified sodium bentonite.

[0096] The modified zirconia is yttrium-stabilized zirconia supported on a porous carbon material, and the specific preparation method includes the following steps:

[0097] (1) Mix ZrOCl2·8H2O, YCl3·6H2O and urea, the molar ratio of ZrOCl2·8H2O to YCl3·6H2O is 1:1, and the molar ratio of ZrOCl2·8H2O to urea is 1:1.2. Carry out hydrothermal treatment at 220°C and 7 MPa for 5 h, dry at 120°C for 10 h, calcine at 900°C for 1 h, use a variable-frequency planetary ball mill and high-aluminum ball milling medium, carry out ball milling for 12 h under the conditions of a water-ball-material ratio of 6:2:1 and a ball mill rotation speed of 400 r / min, and dry at 120°C for 10 h to obtain yttrium-stabilized zirconia;

[0098] (2) Dissolve zinc nitrate hexahydrate and 2-methylimidazole in ethanol respectively. The mass-volume ratio of zinc nitrate hexahydrate to ethanol is 1:42, and the mass-volume ratio of 2-methylimidazole to ethanol is 1:16. Perform ultrasonic treatment at a power of 300 W for 0.5 h to obtain a clear solution. Mix them, reflux and heat at 65 °C for 1 h, stir, separate and collect the precipitate, wash it 3 times with ethanol, dry it in vacuum at 70 °C for 12 h, and calcine it at 800 °C under the protection of inert gas for 2 h to obtain a porous carbon material.

[0099] (3) Disperse the porous carbon material and yttrium-stabilized zirconia in a beaker. The mass ratio of the porous carbon material to yttrium-stabilized zirconia is 1:4. Perform ultrasonic treatment at a power of 400 W for 1.5 h. The ultrasonic power is 400 W - 800 W. Stir, adjust the pH to 10 with 1 mol / L NaOH solution, perform hydrothermal treatment at 200 °C for 0.5 h, dry at 110 °C and grind and crush to obtain modified zirconia.

[0100] Example 5

[0101] A high-performance composite bentonite, comprising the following components in parts by weight: 100 parts of modified bentonite; 5 parts of modified zirconia; 10 parts of vermiculite; 20 parts of diatomite.

[0102] A preparation method of a high-performance composite bentonite specifically comprises the following steps:

[0103] S1. Grind 80 parts by weight of modified bentonite, 15 parts by weight of diatomite, and 10 parts by weight of vermiculite into 400-mesh powder, and mix to obtain a mixed powder;

[0104] S2. Add 2 parts by weight of modified zirconia to the obtained mixed powder, stir and mix evenly, add water at 80 °C and stir to ensure that the solid-liquid mass-volume ratio is 1:3, stir for 0.5 h, dry at 110 °C and grind and crush into 200-mesh powder to obtain the high-performance composite bentonite.

[0105] The modified bentonite is acidified sodium bentonite, and its specific preparation method comprises the following steps:

[0106] [1]. Mix calcium bentonite and a 4% Na2CO3 solution in a mass-volume ratio of 1:2, perform water bath heating at 70 °C for 1 h, and dry to obtain sodium bentonite;

[0107] [2]. Mix sodium bentonite and a 10% sulfuric acid in a mass-volume ratio of 1:4 in a flask, reflux and heat at 70 °C for 6 h, perform centrifugation at a rotational speed of 3000 r / min for 0.5 h, wash, perform ultrasonic treatment at a power of 500 W for 0.5 h, and dry at 100 °C for 8 h to obtain acidified sodium bentonite.

[0108] The modified zirconia is yttrium-stabilized zirconia supported on porous carbon material, and the specific preparation method includes the following steps:

[0109] (1) Mix ZrOCl2·8H2O, YCl3·6H2O and urea. The molar ratio of ZrOCl2·8H2O to YCl3·6H2O is 1:1, and the molar ratio of ZrOCl2·8H2O to urea is 1:1.2. Perform hydrothermal treatment at 220 °C and 7 MPa for 5 h, dry at 120 °C for 10 h, calcine at 800 °C for 1 h. Use a variable-frequency planetary ball mill with high-aluminum ball milling medium, and ball mill for 12 h under the conditions of a water-ball-material ratio of 6:2:1 and a ball mill rotation speed of 400 r / min. Dry at 120 °C for 10 h to obtain yttrium-stabilized zirconia;

[0110] (2) Dissolve zinc nitrate hexahydrate and 2-methylimidazole in ethanol respectively. The mass-volume ratio of zinc nitrate hexahydrate to ethanol is 1:42, and the mass-volume ratio of 2-methylimidazole to ethanol is 1:16. Perform ultrasonic treatment at a power of 500 W for 0.5 h to obtain a clear solution. Mix them, reflux and heat at 65 °C for 1 h, stir, separate and collect the precipitate. Wash it 3 times with ethanol, dry it under vacuum at 70 °C for 12 h, and calcine it at 900 °C under inert gas protection for 2 h to obtain porous carbon material.

[0111] (3) Disperse the porous carbon material and yttrium-stabilized zirconia in a beaker. The mass ratio of the porous carbon material to yttrium-stabilized zirconia is 1:4. Perform ultrasonic treatment at a power of 400 W for 1.5 h, stir, adjust the pH to 10 with 1 mol / L NaOH solution, perform hydrothermal treatment at 200 °C for 0.5 h, and obtain modified zirconia after drying at 110 °C and grinding.

[0112] Comparative Example 1

[0113] This comparative example provides a high-performance composite bentonite, and the difference from Example 1 is only that the modified zirconia is not included in all components, and the other components and component contents are the same as those in Example 1.

[0114] Comparative Example 2

[0115] This comparative example provides a high-performance composite bentonite, and the difference from Example 1 is only that the bentonite in all components is ordinary calcareous bentonite, and the other components and component contents are the same as those in Example 1.

[0116] Comparative Example 3

[0117] This comparative example provides a high-performance composite bentonite, and the difference from Example 1 is that only ordinary calcareous bentonite is included in all components.

[0118] Experimental Example:

[0119] 1. The adsorption experiment was used to simulate the sewage treatment of the high-performance composite bentonites prepared in Examples 1-5 of the present invention and Comparative Examples 1-3 at room temperature. Preparation of simulated sewage: Weigh 1.59 g of Pb(NO3) 2、 4.58 g of Zn(NO3)2·6H2O, 2.74 g of Cd(NO3)2·4H2O and 20 mL of arsenic water were dissolved in ultrapure water, 500 mL of KH2PO4 solution with a concentration of 10 mg / L was added, and the volume was fixed to 1000 mL to prepare a standard stock solution with a mass concentration of 1000 mg / L for lead, zinc and cadmium ions, an arsenic ion concentration of 20 mg / L, a phosphorus concentration of 5 mg / L, and concentrated sulfuric acid was added dropwise to adjust the pH value of the solution to 3.5.

[0120] Adsorption experiment: Weigh 1 g of the high-performance composite bentonites prepared in Examples 1-5 and the composite bentonites prepared in Comparative Examples 1-3 respectively, and put them into 50 mL of simulated sewage mixed solution respectively. After oscillating for a certain time on a water bath oscillator at room temperature, centrifuge and separate, take the supernatant, filter it through a 0.45 μm filter membrane, measure the remaining mass concentration of each ion in the filtrate, calculate the removal rate of each ion, and the removal rate is calculated according to the following formula.

[0121] R=(Co-Ct) / Co*100%

[0122] In the formula: Co is the initial mass concentration of the adsorbate in the wastewater, mg / L; Ct is the remaining mass concentration of the adsorbate in the sewage at the adsorption time of t, mg / L; R is the removal rate, %.

[0123] 2. The high-performance composite bentonite prepared in Example 1 of the present invention was observed by scanning electron microscope SEM.

[0124] Result analysis

[0125] Figure 1 It is the adsorption result diagram of the acid root ions prepared in Examples 1-5 of the present invention and Comparative Examples 1-3. As shown in the figure, the removal rates of the high-performance composite bentonites prepared in Examples 1-5 for phosphate ions and sulfate ions are higher than those of the composite bentonites prepared in Comparative Examples 1-3. The removal rates of the high-performance composite bentonites prepared in Examples 1-5 for phosphate ions and sulfate ions can reach more than 90%, and the adsorption capacity for phosphate ions and sulfate ions is greater.

[0126] Figure 2This is the adsorption result graph of heavy metal ions prepared in Examples 1-5 and Comparative Examples 1-3 of the present invention. As shown in the figure, the high-performance composite bentonite prepared in Examples 1-5 has a higher removal rate of Pd ions, Cd ions, Zn ions, and As ions than that in Comparative Examples 1-3. The removal rate has been greatly improved, all greater than 80%, and the adsorption capacity for Pd ions, Cd ions, Zn ions, and As ions is greater.

[0127] Figure 3 This is the adsorption time result graph of the maximum adsorption amount of acid radical ions prepared in Examples 1-5 and Comparative Examples 1-3 of the present invention. As shown in the figure, the removal time of phosphate ions and sulfate ions by the high-performance composite bentonite prepared in Examples 1-5 is less than that of the composite bentonite prepared in Comparative Examples 1-3, indicating that within the same time, the high-performance composite bentonite prepared in Examples 1-5 has a faster adsorption rate for phosphate ions and sulfate ions.

[0128] Figure 4 This is the adsorption time result graph of the maximum adsorption amount of heavy metal ions prepared in Examples 1-5 and Comparative Examples 1-3 of the present invention. As shown in the figure, the removal time of Pd ions, Cd ions, Zn ions, and As ions by the high-performance composite bentonite prepared in Examples 1-5 is less than that of the composite bentonite prepared in Comparative Examples 1-3, indicating that within the same time, the high-performance composite bentonite prepared in Examples 1-5 has a faster adsorption rate for Pd ions, Cd ions, Zn ions, and As ions.

[0129] Figure 5 This is the scanning electron microscope result graph of Example 1 of the present invention. As shown in the figure, the high-performance composite bentonite particles are small and the aggregation morphology is irregular, providing more adsorption vacancies for the particles. The flaky structure is small, the surface is rough, and some show scaly shapes, increasing the specific surface area.

[0130] The high-performance composite bentonite enhances the treatment ability of pollutants by modifying bentonite and adding modified zirconia. The modified bentonite is sodium acidified bentonite, and sodium ions are more conducive to cation exchange. The specific surface area of the acidified bentonite increases, and the adsorption effect is improved.

[0131] On the surface of modified zirconia, phosphate adsorbs with modified zirconia particles to form an inner spherical phosphate anion surface complex. The hydrated form of modified zirconia can provide hydroxide ions and water molecules, which is conducive to phosphate exchange. The tetravalent zirconium in modified zirconia has chemical affinity with sulfate ions. Therefore, modified zirconia has good adsorption capacity for phosphate ions and sulfate ions; the surface of zirconia particles in hydrated form contains abundant hydroxyl groups, which can undergo ligand exchange with heavy metal ions.

[0132] Using porous carbon materials as carriers increases the pore volume and specific surface area of the porous carbon materials, making it easier to exchange with heavy metal ions and allowing pollutant molecules to better enter the porous carbon structure. The van der Waals force between carbon molecules and pollutant molecules increases, and at the same time, it is easier to share electron pairs or transfer electrons with pollutants, causing the pollutants to be adsorbed onto the surface of the carbon material, reducing the free energy of the pollutants and making them more easily adsorbed.

[0133] Vermiculite and diatomite have a relatively large specific surface area and good interlayer cation exchange ability and adsorption ability. They can associate with colloidal particles and polar molecules on the surface of sewage to form aggregates for easy separation, further enhancing the sewage treatment ability of bentonite.

[0134] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

[0135] The above description of the present invention and its embodiments is not restrictive. What is shown in the drawings is only one of the embodiments of the present invention, and the actual application is not limited thereto. Generally speaking, if those of ordinary skill in the art are inspired by it and design similar methods and embodiments without creative efforts without departing from the purpose of the present invention, they shall fall within the protection scope of the present invention.

Claims

1. A high-performance composite bentonite, characterized in that: Comprising the following components in parts by weight: 80 - 100 parts of modified bentonite; 2 - 5 parts of modified zirconia; 10 - 15 parts of vermiculite; 15 - 20 parts of diatomite; The modified bentonite is acidified sodium bentonite, and the specific preparation method comprises the following steps: 【1】Subject calcium bentonite and Na₂CO₃ solution to water bath heating and drying to obtain sodium bentonite; 【2】Mix sodium bentonite and sulfuric acid, conduct reflux heating, centrifugation, washing, ultrasonic treatment, and drying to obtain acidified sodium bentonite; The modified zirconia is yttrium - stabilized zirconia supported on porous carbon material, and the specific preparation method comprises the following steps: (1) Mix ZrOCl₂·8H₂O, YCl₃·6H₂O and urea, conduct hydrothermal treatment, first drying, calcination, ball milling, and second drying to obtain yttrium - stabilized zirconia; (2) Dissolve zinc nitrate hexahydrate and 2 - methylimidazole in ethanol respectively, conduct ultrasonic treatment, mix after obtaining a clear solution to ensure the mixed solution is clear and transparent, conduct reflux heating, stirring, separation, collect the precipitate, wash, vacuum dry, calcine, and keep warm to obtain porous carbon material; (3) Disperse the porous carbon material and yttrium - stabilized zirconia in a beaker, conduct ultrasonic treatment, stirring, adjust the pH, hydrothermal treatment, drying, grinding and pulverization to obtain modified zirconia.

2. The high-performance composite bentonite according to claim 1, characterized in that: In step 【1】, the mass - to - volume ratio of calcium bentonite to Na₂CO₃ solution is 1:2, the mass concentration of Na₂CO₃ solution is 4%, the water bath heating temperature is 70 °C, and the heating time is 1 h.

3. The high-performance composite bentonite according to claim 2, wherein: In step 【2】, the mass - to - volume ratio of sodium bentonite to sulfuric acid is 1:4, the mass concentration of sulfuric acid is 10%, the reflux heating temperature is 70 °C, the reflux time is 6 h, the centrifugation speed is 3000 r / min, the centrifugation time is 0.5 h, the ultrasonic treatment is carried out at a power of 500 W for 0.5 h, the drying temperature is 100 - 110 °C, and the drying time is 8 h.

4. A high-performance composite bentonite according to claim 3, characterized in that: In (1), the molar ratio of ZrOCl₂·8H₂O to YCl₃·6H₂O is 1:1, the molar ratio of ZrOCl₂·8H₂O to urea is 1:1.2, the hydrothermal treatment temperature is 220 °C, the pressure is 7 MPa, the treatment time is 5 h, the first drying temperature is 120 °C, the first drying time is 10 h, the calcination temperature is 800 - 900 °C, the calcination time is 1 h, the ball milling device is a variable - frequency planetary ball mill, the ball milling medium is high - alumina balls, the water - ball - material ratio is 6:2:1, the grinding time is 12 h, the ball mill speed is 400 r / min, the second drying temperature is 120 °C, and the second drying time is 10 h.

5. The high-performance composite bentonite according to claim 4, wherein: In (2), the mass - to - volume ratio of zinc nitrate hexahydrate to ethanol is 1:42, the mass - to - volume ratio of 2 - methylimidazole to ethanol is 1:16, the ultrasonic treatment is carried out at a power of 300 W - 500 W for 0.5 h, the reflux heating temperature is 65 °C, the reaction time is 1 h, it is washed 3 times with ethanol, vacuum dried at 70 °C for 12 h, the calcination temperature is 800 °C - 900 °C, the calcination is carried out under inert gas protection, and the heat preservation time is 2 h.

6. The high-performance composite bentonite according to claim 5, wherein: In (3), the mass ratio of the porous carbon material to yttria-stabilized zirconia is 1:4, and it is dispersed for 1.5 h under the condition that the ultrasonic power is 400 W to 800 W. The pH is adjusted to 10 with 1 mol / L NaOH solution, the hydrothermal treatment temperature is 200 °C, the treatment duration is 0.5 h, and the drying temperature is 100 to 110 °C.

7. The preparation method of a high-performance composite bentonite according to any one of claims 1-6, characterized in that: Specifically, it includes the following steps: S1. Grind the modified bentonite, diatomite, and vermiculite into powders and mix them to obtain a mixed powder. S2. Mix the above-mentioned mixed powder with the modified zirconia, add water and stir, dry and grind into powder to obtain the high-performance composite bentonite.

8. The preparation method of a high-performance composite bentonite according to claim 7, characterized in that: In S1, it is ground into a 400-mesh powder; in S2, the water temperature is 80 °C, the solid-liquid mass-volume ratio is 1:3, the stirring duration is 0.5 h, the drying temperature is 100 to 110 °C, and it is ground into a 200-mesh powder.

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