Preparation of manganese-loaded soybean residue roasted charcoal and its application in purifying malachite green in ornamental fish aquaculture water

Abstract

This invention discloses a method for preparing manganese-loaded soybean residue baked charcoal and its application in purifying malachite green in ornamental fish aquaculture water. The invention uses soybean residue as raw material, which is washed, dried, and pulverized. It is then pretreated by soaking in a phosphoric acid solution, followed by manganese loading through soaking in a potassium permanganate buffer solution. Finally, the manganese-loaded soybean residue baked charcoal is obtained through low-temperature baking technology. This invention not only realizes the value-added utilization of soybean residue and low-temperature waste heat resources, but also the prepared manganese-loaded soybean residue baked charcoal exhibits a high adsorption capacity for malachite green in water, with a maximum adsorption capacity of 373.4 mg / g, making it a highly efficient adsorbent for purifying malachite green in ornamental fish aquaculture water.

Description

Technical Field

[0001] This invention belongs to the field of water pollution control and adsorption materials technology, specifically relating to a manganese-loaded roasted charcoal made from soybean residue and its application in purifying malachite green in ornamental fish aquaculture water. Background Technology

[0002] Malachite green is a triphenylmethane compound used as a fish medicine to treat diseases in ornamental fish caused by bacterial, fungal, and parasitic infections, especially effective against saprolegniasis. However, malachite green has potential carcinogenic, teratogenic, and mutagenic effects, and untreated water containing malachite green can pose a potential environmental hazard. Therefore, efficiently, safely, and conveniently purifying malachite green from ornamental fish tanks, especially small home aquariums, has significant economic and environmental value. Currently, malachite green purification technologies mainly include photocatalysis, microbial methods, membrane treatment, and adsorption. However, photocatalysis, microbial methods, and membrane treatment all suffer from high equipment investment, high treatment costs, and difficulty in miniaturization. Adsorption, on the other hand, offers the advantages of simplicity and ease of implementation.

[0003] Soybean dregs are a common kitchen waste residue generated during the production of soy milk and tofu. They are green, safe, and non-toxic, rich in effective adsorption groups such as hydroxyl, carboxyl, and amino groups, and can be used to purify malachite green in water. However, they suffer from drawbacks such as easy spoilage and weak adsorption capacity. This invention uses soybean dregs as raw material and employs pretreatment, buffer salt-controlled manganese loading, and low-temperature baking techniques to prepare manganese-loaded soybean dregs baked charcoal. This manganese-loaded soybean dregs baked charcoal is then used to purify malachite green in ornamental fish aquaculture water, overcoming the shortcomings of soybean dregs as a malachite green purifier, namely easy spoilage and weak adsorption capacity. Summary of the Invention

[0004] The purpose of this invention is to provide a manganese-loaded soybean residue roasted charcoal and its preparation method, which can be used as a highly efficient adsorbent for purifying malachite green in ornamental fish aquaculture water.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A manganese-loaded soybean residue baking charcoal, the preparation method of which includes the following steps:

[0007] 1) Preparation of raw materials: Wash and dry the soybean residue, then crush and sieve it to obtain soybean residue powder;

[0008] 2) Pretreatment of raw materials: The soybean residue powder obtained in step 1) is soaked in phosphoric acid solution at room temperature, filtered and dried to obtain pretreated soybean residue;

[0009] 3) Preparation of manganese-loaded soybean residue: Sodium phosphate buffer solution was added to potassium permanganate solution to obtain potassium permanganate buffer solution; then the pretreated soybean residue obtained in step 2) was added, soaked at room temperature, filtered and dried to obtain manganese-loaded soybean residue;

[0010] 4) Low-temperature baking: The manganese-loaded soybean residue prepared in step 3) is placed in a tube furnace and baked at low temperature under a nitrogen atmosphere. After cooling to room temperature, it is taken out, washed and dried to obtain the manganese-loaded soybean residue baking charcoal.

[0011] Furthermore, the particle size of the soybean residue powder obtained in step 1) is 20~100 mesh.

[0012] Furthermore, the mass concentration of the phosphoric acid solution in step 2) is 30-50%.

[0013] Furthermore, in step 2), the solid-liquid ratio of soybean residue powder and phosphoric acid solution is 1 g: 5 mL to 1 g: 10 mL.

[0014] Further, the concentration of the sodium phosphate buffer solution in step 3) is 0.05~0.2 M.

[0015] Further, the concentration of the potassium permanganate solution in step 3) is 0.1~0.5 M.

[0016] Furthermore, the pH value of the potassium permanganate buffer solution obtained in step 3) is 11~13.

[0017] Furthermore, in step 3), the solid-liquid ratio of the pretreated soybean residue and potassium permanganate buffer solution is 1 g:5 mL to 1 g:10 mL.

[0018] Furthermore, the soaking time in steps 2) and 3) is 2 to 6 hours.

[0019] Furthermore, in step 4), the flow rate of nitrogen is 50~150 mL / min.

[0020] Furthermore, the low-temperature baking in step 4) is performed at a temperature of 100~300℃ for 0.5~2 hours. During the baking process, MnO crystals are formed with an average crystal size of 28nm.

[0021] The manganese-loaded soybean residue roasted charcoal has a high adsorption capacity for malachite green in water and can be used as an adsorbent to purify malachite green in ornamental fish farming water.

[0022] The beneficial effects and outstanding advantages of this invention are as follows:

[0023] (1) This invention uses kitchen waste soybean residue as raw material, and obtains manganese-loaded soybean residue baking charcoal through pretreatment, buffer salt regulation of manganese loading and low temperature baking technology, thereby realizing the value-added utilization of kitchen waste soybean residue.

[0024] (2) The manganese-loaded soybean residue roasted carbon prepared in this invention has a high adsorption capacity for malachite green in water. Its adsorption mechanism is mainly hydrogen bonding mechanism (dipole-dipole hydrogen bond and Yoshida hydrogen bond). The maximum adsorption capacity can reach 373.4 mg / g. It can be used as a high-efficiency adsorbent for purifying malachite green in ornamental fish breeding water.

[0025] (3) The present invention uses low-temperature baking technology to prepare manganese-loaded soybean residue baking charcoal, which can realize the value-added utilization of low-temperature waste heat resources (<300℃) in industry, and has the advantages of energy saving and consumption reduction. Attached Figure Description

[0026] Figure 1 The XRD pattern is shown for the manganese-loaded soybean residue roasted charcoal prepared in Example 1. Detailed Implementation

[0027] A manganese-loaded soybean residue baking charcoal, the preparation method of which includes the following steps:

[0028] 1) Preparation of raw materials: Wash and dry the soybean residue, then pulverize it through a 20-100 mesh sieve to obtain soybean residue powder;

[0029] 2) Pretreatment of raw materials: The soybean residue powder obtained in step 1) is soaked in a phosphoric acid solution with a mass concentration of 30-50% for 2-6 hours at room temperature according to a solid-liquid ratio of 1 g:5 mL to 1 g:10 mL, then filtered and dried to obtain pretreated soybean residue.

[0030] 3) Preparation of manganese-loaded soybean residue: Add 0.05~0.2 M sodium phosphate buffer solution to 0.1~0.5 M potassium permanganate solution until the pH of the mixed solution reaches 11~13 to obtain potassium permanganate buffer solution; then add the pretreated soybean residue obtained in step 2) at a solid-liquid ratio of 1 g:5 mL~1 g:10 mL, soak at room temperature for 2~6 h, filter and dry to obtain manganese-loaded soybean residue;

[0031] 4) Low-temperature baking: The manganese-loaded soybean residue prepared in step 3) is placed in a tube furnace and baked at a low temperature of 100-300°C for 0.5-2 h under a nitrogen atmosphere with a flow rate of 50-150 mL / min. After cooling to room temperature, it is taken out, washed and dried to obtain manganese-loaded soybean residue baking charcoal.

[0032] To make the content of this invention easier to understand, the technical solution of this invention will be further described below with reference to specific embodiments, but this invention is not limited thereto.

[0033] Example 1

[0034] Soybean residue was washed with water, dried, and then pulverized through a 20-100 mesh sieve. 3 g of soybean residue powder was then added to 30 mL of a 40% phosphoric acid solution and soaked at room temperature for 4 h. After filtration and drying, pretreated soybean residue was obtained. A 0.2 M sodium phosphate buffer solution was slowly added to a 0.5 M potassium permanganate solution until the pH of the mixed solution reached 12.5 ± 0.5, yielding a potassium permanganate buffer solution. The pretreated soybean residue was then added to the potassium permanganate buffer solution at a solid-liquid ratio of 1 g:10 mL, mixed, and soaked at room temperature for 4 h. After filtration and drying, manganese-loaded soybean residue was obtained. The manganese-loaded soybean residue was then carbonized at 200℃ for 45 min under a nitrogen atmosphere (flow rate 60 mL / min). After cooling to room temperature, it was removed, washed, and dried to obtain manganese-loaded soybean residue charcoal.

[0035] Example 2

[0036] Soybean residue was washed with water, dried, and then pulverized through a 20-100 mesh sieve. 3 g of soybean residue powder was then added to 30 mL of a 40% phosphoric acid solution and soaked at room temperature for 4 h. After filtration and drying, pretreated soybean residue was obtained. A 0.2 M sodium phosphate buffer solution was slowly added to a 0.5 M potassium permanganate solution until the pH of the mixed solution reached 12.5 ± 0.5, yielding a potassium permanganate buffer solution. The pretreated soybean residue was then added to the potassium permanganate buffer solution at a solid-liquid ratio of 1 g: 5 mL, mixed, and soaked at room temperature for 4 h. After filtration and drying, manganese-loaded soybean residue was obtained. The manganese-loaded soybean residue was then carbonized at 200℃ for 45 min under a nitrogen atmosphere (flow rate 60 mL / min). After cooling to room temperature, it was removed, washed, and dried to obtain manganese-loaded soybean residue charcoal.

[0037] Example 3

[0038] Soybean residue was washed with water, dried, and then pulverized through a 20-100 mesh sieve. 3 g of soybean residue powder was then added to 30 mL of a 40% phosphoric acid solution and soaked at room temperature for 4 h. After filtration and drying, pretreated soybean residue was obtained. A 0.05 M sodium phosphate buffer solution was slowly added to a 0.1 M potassium permanganate solution until the pH of the mixed solution reached 12.0 ± 0.5, yielding a potassium permanganate buffer solution. The pretreated soybean residue was then added to the potassium permanganate buffer solution at a solid-liquid ratio of 1 g:10 mL, mixed, and soaked at room temperature for 4 h. After filtration and drying, manganese-loaded soybean residue was obtained. The manganese-loaded soybean residue was then carbonized at 200℃ for 45 min under a nitrogen atmosphere (flow rate 60 mL / min). After cooling to room temperature, it was removed, washed, and dried to obtain manganese-loaded soybean residue charcoal.

[0039] Example 4

[0040] Soybean residue was washed with water, dried, and then pulverized through a 20-100 mesh sieve. 3 g of soybean residue powder was then added to 30 mL of a 40% phosphoric acid solution and soaked at room temperature for 4 h. After filtration and drying, pretreated soybean residue was obtained. A 0.05 M sodium phosphate buffer solution was slowly added to a 0.1 M potassium permanganate solution until the pH of the mixed solution reached 12.0 ± 0.5, yielding a potassium permanganate buffer solution. The pretreated soybean residue was then added to the potassium permanganate buffer solution at a solid-liquid ratio of 1 g: 5 mL. After mixing, the mixture was soaked at room temperature for 4 h, filtered, and dried to obtain manganese-loaded soybean residue. The manganese-loaded soybean residue was then carbonized at 200℃ for 45 min under a nitrogen atmosphere (flow rate 60 mL / min). After cooling to room temperature, it was removed, washed, and dried to obtain manganese-loaded soybean residue charcoal.

[0041] Application Example 1

[0042] 0.008 g of each of the manganese-loaded soybean residue baking charcoal prepared in Examples 1-4 was placed in 10 mL of deionized water with a malachite green content of 300 mg / L and adsorbed at room temperature for 12 h. The results showed that the adsorption capacity of the manganese-loaded soybean residue baking charcoal prepared in Examples 1-4 for malachite green in deionized water was 369.7 mg / g, 369.3 mg / g, 348.2 mg / g, and 348.6 mg / g, respectively, with removal rates of 98.6%, 98.5%, 92.9%, and 93.0%, respectively.

[0043] Application Example 2

[0044] 0.008 g of each of the manganese-loaded soybean residue roasted charcoal prepared in Examples 1-4 was placed in 10 mL of water in a small household aquarium with a malachite green content of 300 mg / L, and adsorbed at room temperature for 12 h. The results showed that the adsorption capacity of the manganese-loaded soybean residue roasted charcoal prepared in Examples 1-4 for malachite green in the water of the small household aquarium was 367.2 mg / g, 366.3 mg / g, 342.6 mg / g, and 340.0 mg / g, respectively, with removal rates of 97.9%, 97.7%, 91.4%, and 90.7%, respectively.

[0045] Application Example 3

[0046] 0.008 g of each of the manganese-loaded soybean residue roasted charcoal prepared in Examples 1-4 was placed in 10 mL of ornamental fish aquaculture water containing 300 mg / L of malachite green, and adsorbed at room temperature for 12 h. The results showed that the adsorption capacity of the manganese-loaded soybean residue roasted charcoal prepared in Examples 1-4 for malachite green in ornamental fish aquaculture water was 373.4 mg / g, 371.6 mg / g, 353.2 mg / g, and 351.4 mg / g, respectively, with removal rates of 99.6%, 91.1%, 94.2%, and 93.7%, respectively.

[0047] Application Comparative Example 1

[0048] Soybean residue was washed with water, dried, and then pulverized through a 20-100 mesh sieve. 0.008 g of the pulverized residue was placed in 10 mL of different water bodies containing 300 mg / L malachite green (deionized water, water for a small household aquarium, and water for ornamental fish farming, respectively), and adsorbed at room temperature for 12 h. The results showed that the adsorption capacity of soybean residue for malachite green in the three different water bodies was 38.4 mg / g, 35.2 mg / g, and 39.2 mg / g, respectively, with removal rates of 10.2%, 9.4%, and 10.5%.

[0049] Application Comparative Example 2

[0050] Soybean residue was washed with water, dried, and then pulverized through a 20-100 mesh sieve. 3 g of soybean residue powder was then added to 30 mL of a 40% phosphoric acid solution and soaked at room temperature for 4 h. After filtration and drying, pretreated soybean residue was obtained. Next, the pretreated soybean residue was added to a 0.5 M potassium permanganate solution at a solid-liquid ratio of 1 g:10 mL, mixed, and soaked at room temperature for 4 h. After filtration and drying, manganese-loaded soybean residue was obtained. The manganese-loaded soybean residue was then carbonized at 200℃ for 45 min under a nitrogen atmosphere (flow rate 60 mL / min). After cooling to room temperature, it was removed, washed, and dried to obtain a comparative sample of manganese-loaded soybean residue roasted charcoal.

[0051] 0.008 g of the above-mentioned control sample was placed in 10 mL of deionized water with a malachite green content of 300 mg / L and adsorbed at room temperature for 12 h. The results showed that the control sample adsorbed 269.25 mg / g of malachite green in the water, with a removal rate of 71.75%. This indicates that the use of sodium phosphate buffer solution has a significant impact on the adsorption performance of the obtained manganese-loaded soybean residue roasted charcoal.

[0052] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should be included in the scope of the present invention.

Claims

1. A process for the preparation of a manganese-loaded okara-based baked carbon, characterized by: Comprising the following steps: 1) Preparation of raw material: washing, drying and then crushing and sieving the okara to obtain okara powder; 2) Pretreatment of raw material: soaking the okara powder prepared in step 1) in a phosphoric acid solution at room temperature, then filtering and drying to obtain pretreated okara; 3) Preparation of manganese-loaded okara: adding a sodium phosphate buffer salt solution to a potassium permanganate solution to obtain a potassium permanganate buffer solution; then adding the pretreated okara obtained in step 2), soaking at room temperature, then filtering and drying to obtain manganese-loaded okara; 4) Low-temperature roasting: placing the manganese-loaded okara prepared in step 3) in a tube furnace, performing low-temperature roasting under a nitrogen atmosphere, then cooling to room temperature, taking out, washing and drying to obtain the manganese-loaded okara roasted carbon.

2. A process for the preparation of a baked carbon loaded with manganese from okara according to claim 1, characterized in that: The particle size of the okara powder obtained in step 1) is 20-100 mesh.

3. A process for the preparation of a baked carbon loaded with manganese from okara according to claim 1, characterized in that: In step 2), the solid-liquid ratio of the okara powder and the phosphoric acid solution is 1 g:5 mL-1 g:10 mL; the mass concentration of the phosphoric acid solution is 30-50%.

4. The method for preparing a manganese-loaded okara-based baked carbon according to claim 1, characterized by: In step 3), the concentration of the sodium phosphate buffer salt solution is 0.05-0.2 M, the concentration of the potassium permanganate solution is 0.1-0.5 M, and the pH value of the obtained potassium permanganate buffer solution is 11-13.

5. The method for preparing a manganese-loaded okara-based baked carbon according to claim 1, characterized by: In step 3), the solid-liquid ratio of the pretreated okara and the potassium permanganate buffer solution is 1 g:5 mL-1 g:10 mL.

6. A process for the preparation of a baked carbon loaded with manganese from okara according to claim 1, characterized in that: In steps 2) and 3), the soaking time is 2-6 h.

7. A method of preparing a manganese-loaded okara-based baked carbon according to claim 1, characterized by: In step 4), the flow rate of nitrogen is 50-150 mL / min.

8. A process for the preparation of a baked carbon loaded with manganese from okara according to claim 1, characterized by: In step 4), the temperature of the low-temperature roasting is 100-300℃, and the time is 0.5-2 h.

9. A manganese-loaded okara roasted carbon prepared by the method of claim 1.

10. Use of the manganese-loaded okara roasted carbon of claim 9 in purifying malachite green in ornamental fish breeding water bodies.

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