Magnesia-slag-based foamed material and method for producing the same

Abstract

The application belongs to the technical field of foamed materials, and particularly relates to a magnesium slag-based foamed material and a preparation method thereof. The magnesium slag-based foamed material is made of the following components in mass fraction: magnesium slag 56%, corn cob 1.7%, water glass 27%, sodium hydroxide 4.4%, and tap water 10.9%. The magnesium slag-based foamed material utilizes the thermal decomposition of corn cob at high temperature to form pores, effectively improving the foaming performance of the magnesium slag-based foamed material. The addition of water glass and sodium hydroxide can stimulate the activity of magnesium slag, and enhance the compressive strength of the magnesium slag-based foamed material, overcoming the contradictory problem that the porosity and strength cannot be compatible. The magnesium slag-based foamed material can adsorb metal ions in water, and is conducive to promoting the development of solid waste resource utilization and wastewater treatment functional materials.

Description

Technical Field

[0001] This invention belongs to the field of foaming materials technology, specifically relating to a magnesium slag-based foaming material and its preparation method. Background Technology

[0002] In recent years, with the rapid development of the magnesium smelting industry, China has become a major producer and exporter of magnesium in the world. However, with the rapid development of the magnesium industry, many problems have emerged, such as simple magnesium smelting processes, outdated production equipment, and unstable product quality. In particular, a large amount of waste slag is generated during the magnesium production process.

[0003] Magnesium slag contains a high content of fine powder, with over 60% of the particles having a diameter of less than 100 μm. These particles easily become suspended in the atmosphere, causing dust pollution. Magnesium slag also has strong hygroscopic properties, which can easily lead to soil compaction and salinization, causing soil pollution. Therefore, with many traditional metal resources nearing depletion, the treatment and utilization of magnesium slag and the development of new materials from it are crucial measures for sustainable development.

[0004] Comprehensive treatment of magnesium slag has become a major issue in the clean development of the magnesium industry. High-value, resource-based utilization of the useful elements in magnesium slag, turning it from a hazard into a benefit, can bring significant economic and environmental benefits. In recent years, using industrial solid waste as raw material to prepare wastewater treatment materials has become an important development direction for developing a circular economy, protecting the ecological environment, and achieving energy conservation and emission reduction. Among these, foamed materials have wide applications in many fields, especially demonstrating unique advantages in water treatment. Their excellent thermal insulation properties allow foamed materials to reduce heat transfer, making them suitable for building, refrigeration, and pipe insulation; they also reduce sound wave reflection, exhibiting good sound absorption properties; simultaneously, the porous nature of foamed materials makes them effective filtration media, capable of capturing and removing suspended solids, organic matter, and microorganisms from water; furthermore, due to their unique structure and chemical properties, they possess highly efficient adsorption properties, making foamed materials an effective tool for heavy metal pollution control, used to remove heavy metal ions such as lead, cadmium, and copper from wastewater.

[0005] Foamed materials also have some problems, such as limited adsorption and compressive strength, and they are prone to saturation. Saturated foamed materials need to be safely disposed of to avoid secondary pollution. Summary of the Invention

[0006] Based on the above-mentioned technical problems, this invention is based on the principle of treating waste with waste, which is in line with the national requirements for strengthening ecological civilization construction and promoting environmental protection and green development. It proposes a magnesium slag-based foaming material and its preparation method, which is conducive to promoting the development of solid waste resource utilization and wastewater treatment functional materials.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0008] A magnesium slag-based foamed material, said foamed material is made from the following components by mass fraction: 56% magnesium slag, 1.7% corn cob, 27% water glass, 4.4% sodium hydroxide, and 10.9% tap water.

[0009] A method for preparing a magnesium slag-based foamed material as described above includes the following steps:

[0010] (1) Pass the magnesium slag through a 100-mesh sieve, and then crush it together with the corn cob;

[0011] (2) The magnesium slag, corn cob and composite activator obtained in step (1) are stirred at high speed;

[0012] (3) Pour the material mixed in step (2) into the mold and cure it to form;

[0013] (4) Demold the molded sample and calcine it to obtain magnesium slag-based foamed material.

[0014] Furthermore, the composite activator mentioned in step (2) is prepared by mixing water glass, sodium hydroxide and water evenly and then letting it stand for 24 hours.

[0015] Furthermore, the high-speed stirring mentioned in step (2) refers to a stirring speed of 1500-2000 r / min and a stirring time of 10-20 min.

[0016] Furthermore, the curing and molding conditions described in step (3) are curing at a constant temperature of 60℃ for 24 hours.

[0017] Furthermore, the roasting conditions described in step (4) are a roasting temperature of 400–550°C and a roasting time of 4–6 h.

[0018] Application of a magnesium slag-based foamed material as described above in the adsorption of metal ions in water.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] 1. This invention utilizes corn cob as a foaming agent, which not only effectively utilizes agricultural waste and improves environmental pollution, but also uses the gas generated by the thermal decomposition of biomass at high temperature to create pores. The network connection effect of biomass and the binding effect of pectin produced after biomass decomposition enhance the compressive strength of the foaming material and reduce the amount of composite activator added.

[0021] 2. Compared with hydrogen peroxide foaming, the biomass foaming process of the present invention is easier to control, has better porosity, and also solves the problem of low foaming strength of hydrogen peroxide.

[0022] 3. The magnesium slag-based foamed material prepared using the present invention can significantly enhance the strength of the foamed material and improve its porosity. Detailed Implementation

[0023] To facilitate understanding of the present invention, a more comprehensive description will be given below. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the present invention.

[0024] Example 1

[0025] (1) Pass the magnesium slag through a 100-mesh sieve, take the sieved sample, and crush the corn cob to less than 1 mm;

[0026] (2) Mix 27% water glass, 4.4% sodium hydroxide and 10.9% water according to mass fraction, let stand for 24 hours to prepare a composite activator, and then add it to a stirrer with 56% magnesium slag and 1.7% corn cob, and stir at 2000 r / min for 10 min.

[0027] (3) Inject the mixed material into the silicone mold and cure it in a constant temperature curing chamber at 60°C for 24 hours to form the final product;

[0028] (4) After demolding the molded sample, place it in a muffle furnace and calcine at 550°C for 6 hours to obtain magnesium slag-based foamed material.

[0029] The prepared magnesium slag-based foamed material had a total porosity of 13.4%, a compressive strength of 4.06 MPa, an average pore size of 87.19 μm, and a resistance to Pb in water. 2+ The adsorption capacity was 303.95 mg / g.

[0030] Example 2

[0031] (1) Pass the magnesium slag through a 100-mesh sieve, take the sieved sample, and crush the corn cob to less than 1 mm;

[0032] (2) Mix 27% water glass, 4.4% sodium hydroxide and 10.9% water according to mass fraction, let stand for 24 hours to prepare a composite activator, and then add it to a stirrer with 56% magnesium slag and 1.7% corn cob, and stir at 1800 r / min for 12 min.

[0033] (3) Inject the mixed material into the silicone mold and cure it in a constant temperature curing chamber at 60°C for 24 hours to form the final product;

[0034] (4) After demolding the molded sample, place it in a muffle furnace and calcine at 400℃ for 6 hours to obtain magnesium slag-based foamed material.

[0035] The prepared magnesium slag-based foamed material had a total porosity of 10.56%, a compressive strength of 5.29 MPa, an average pore size of 66.49 μm, and a resistance to Pb in water. 2+ The adsorption capacity was 298.43 mg / g.

[0036] Example 3

[0037] (1) Pass the magnesium slag through a 100-mesh sieve, take the sieved sample, and crush the corn cob to less than 1 mm;

[0038] (2) Mix 27% water glass, 4.4% sodium hydroxide and 10.9% water according to mass fraction, let stand for 24 hours to prepare a composite activator, and then add it to a stirrer with 56% magnesium slag and 1.7% corn cob, and stir at 1500 r / min for 20 min.

[0039] (3) Inject the mixed material into the silicone mold and cure it in a constant temperature curing chamber at 60°C for 24 hours to form the final product;

[0040] (4) After demolding the molded sample, place it in a muffle furnace and bake at 500℃ for 5 hours to obtain magnesium slag-based foamed material.

[0041] The prepared magnesium slag-based foamed material had a total porosity of 12.7%, a compressive strength of 5.15 MPa, an average pore size of 80.44 μm, and a resistance to Pb in water. 2+ The adsorption capacity was 313.08 mg / g.

[0042] The embodiments described above are merely specific examples of the present invention, and while the descriptions are detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A magnesium-slag based foamed material, characterized in that, The foaming material is made from the following components by mass fraction: 56% magnesium slag, 1.7% corn cob, 27% water glass, 4.4% sodium hydroxide, and 10.9% tap water; The preparation method of the magnesium slag-based foamed material includes the following steps: (1) Pass the magnesium slag through a 100-mesh sieve, and then crush it together with the corn cob; (2) The magnesium slag, corn cob and composite activator obtained in step (1) are stirred at high speed; (3) Pour the material mixed in step (2) into the mold and cure it to form the desired shape; (4) Demold the molded sample and calcine it to obtain magnesium slag-based foamed material; The composite activator mentioned in step (2) is prepared by mixing water glass, sodium hydroxide and water evenly and then letting it stand for 24 hours; the high-speed stirring mentioned in step (2) refers to a stirring speed of 1500~2000 r / min and a stirring time of 10~20 min; the curing and molding conditions mentioned in step (3) are curing at a constant temperature of 60℃ for 24 hours; the calcination conditions mentioned in step (4) are calcination temperature of 400~550℃ and calcination time of 4~6 hours.

2. The application of the magnesium slag-based foaming material according to claim 1 in the adsorption of metal ions in water.