Ceramic polymer composite culture medium for repairing habitat of deep-sea polymetallic nodule mining area and preparation method of ceramic polymer composite culture medium

Abstract

The invention discloses a deep-sea polymetallic nodule mining area habitat repairing ceramic polymer composite culture medium and a preparation method thereof. The culture medium is composed of a ceramic culture medium blank with the porosity of 10-40% and a polymer coating formed on the surface of the ceramic culture medium blank through crosslinking. Through the innovative material design and preparation method, the defects that in the prior art, a ceramic culture medium is low in biological adhesion efficiency and a high polymer material is insufficient in stability are overcome, an efficient, environment-friendly and economical solution is provided for repairing the habitat of the deep-sea polymetallic nodule mining area, and important application value and popularization potential are achieved.

Description

Technical Field

[0001] This invention belongs to the field of marine environment remediation technology, specifically relating to a ceramic polymer composite culture medium for habitat remediation in deep-sea polymetallic nodule mining areas and its preparation method. Background Technology

[0002] Deep-sea polymetallic nodule deposits contain abundant mineral resources, including transition metals such as manganese, cobalt, nickel, and copper, as well as strategic resources such as rare earth elements and lithium. With the gradual depletion of terrestrial metal mineral resources, deep-sea polymetallic nodules are considered an important source of future metal supply. Since the 1970s, the international community has shown increasing interest in the commercial development of deep-sea mineral deposits, especially against the backdrop of surging demand for metals such as lithium, cobalt, and nickel from new energy technologies and high-end manufacturing. Deep-sea mining has gradually become a hot research area. However, deep-sea mining activities have had significant negative impacts on the fragile deep-sea ecosystem, becoming a pressing problem that needs to be addressed.

[0003] During deep-sea mining, seabed sediments are disturbed on a large scale, forming suspended particle clouds. These clouds can spread over a range of tens of kilometers, covering filter-feeding organisms, clogging their feeding and respiratory systems, and causing benthic animals to suffocate and die. Furthermore, the use of mining equipment directly damages seabed habitats, alters the composition of biological communities, and affects the stability and function of ecosystems. Studies show that even with small-scale mining, the recovery of deep-sea biological communities takes an extremely long time and is unlikely to reach baseline levels in the short term. Deep-sea polymetallic nodules play an irreplaceable role in the ecosystem. As the only hard substrate in the deep-sea plain, they provide crucial sites for the attachment and growth of microorganisms and benthic organisms. The rough structure and porosity of the nodule surface support unique microbial communities, significantly enhancing the biodiversity of the seabed ecosystem and forming an ecological pattern similar to a "biological oasis." However, the removal of polymetallic nodules caused by mining activities is almost irreversible, as their natural formation process takes millions of years, severely limiting the self-repair capacity of deep-sea ecosystems.

[0004] To address the ecological problems caused by deep-sea mining, developing artificial culture media to replace polymetallic nodules and promote habitat restoration has become a research direction. International literature has reported the use of ceramic culture media as rigid substrates for habitat restoration in deep-sea polymetallic nodule mining areas. Ceramic materials are considered ideal alternatives due to their high strength, corrosion resistance, and environmental friendliness. However, ceramic culture media alone have significant limitations in practical applications: their surface bioattachment efficiency is low, making it difficult to rapidly promote the colonization and growth of microorganisms and benthic organisms, thus limiting the effectiveness of habitat restoration. In contrast, polymeric materials (such as chitosan, gelatin, and alginate) can provide carbon sources for microorganisms and enhance their attachment ability due to their good biocompatibility and biodegradability; however, using polymeric materials alone is insufficient to meet the structural stability requirements of the high-pressure environment of the deep sea.

[0005] Currently, there are no reports, either domestically or internationally, on the preparation of composite culture media combining ceramics and polymers and their application in habitat restoration in deep-sea polymetallic nodule mining areas. Existing technologies for preparing ceramic culture media primarily focus on structural design, lacking optimization of bioattachment performance; while polymers, although advantageous in biocompatibility, suffer from insufficient durability and stability, making them unsuitable for long-term adaptation to the extreme deep-sea environment. Therefore, there is an urgent need for a method to prepare artificial culture media that combines structural stability and efficient bioattachment to meet the practical needs of deep-sea habitat restoration. This invention is proposed against this backdrop, aiming to provide an innovative and efficient technical solution for deep-sea ecological restoration by combining the physical advantages of ceramics and the biological advantages of polymers through the preparation of ceramic-polymer composite culture media. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a ceramic polymer composite culture medium for habitat remediation in deep-sea polymetallic nodule mining areas.

[0007] Another objective of this invention is to provide a method for preparing the above-mentioned ceramic polymer composite culture medium for habitat remediation in deep-sea polymetallic nodule mining areas.

[0008] The technical solution of the present invention is as follows:

[0009] A ceramic-polymer composite culture medium for habitat remediation in deep-sea polymetallic nodule mining areas comprises a ceramic culture medium preform with a porosity of 10-40% and a polymer coating formed by cross-linking on the surface of the ceramic culture medium preform.

[0010] The ceramic culture medium ligand was prepared from natural clay and porous particles using a sacrificial template method, with a pore size of 0.01-0.1 mm.

[0011] The polymer coating is made from chitosan, gelatin and alginate.

[0012] In a preferred embodiment of the present invention, the natural clay is mainly composed of clay.

[0013] In a preferred embodiment of the present invention, the pore-forming particles are selected from wood chips, bamboo charcoal, starch, and straw.

[0014] More preferably, the amount of the pore-forming particles added is 20-60 wt%.

[0015] The preparation method of the above-mentioned ceramic polymer composite culture medium for habitat remediation in deep-sea polymetallic nodule mining areas includes the following steps:

[0016] (1) The natural clay and the pore-forming particles are mixed evenly and placed in a mold. The temperature is raised to 1050-1100℃ in 5-6 hours and sintered for 0.8-1.2 hours. After cleaning, the ceramic culture medium blank is obtained.

[0017] (2) The ceramic culture medium blank obtained in step (1) is immersed in an aqueous solution of polymer material monomer, then taken out and air-dried, then immersed in the corresponding divalent metal ion solution for cross-linking reaction, and then dried to obtain the product.

[0018] In a preferred embodiment of the present invention, the cleaning in step (1) is ultrasonic cleaning using a hydrochloric acid solution with a concentration of 4-5%.

[0019] In a preferred embodiment of the present invention, the concentration of the polymer monomer aqueous solution in step (2) is 1-5 wt%.

[0020] More preferably, the solute in the divalent metal ion solution in step (2) is selected from ferrous sulfate, calcium chloride and manganese chloride, with a concentration of 0.005-0.01 mol / L.

[0021] More preferably, the crosslinking reaction in step (2) takes 2-4 hours.

[0022] In a preferred embodiment of the present invention, the mold in step (1) is a plaster mold.

[0023] The beneficial effects of this invention are:

[0024] 1. This invention uses natural clay powder (such as kaolin and deep-sea mining sediments) as raw materials. The materials have high chemical inertness and do not release toxic or harmful substances in the deep-sea environment, thus avoiding secondary pollution to the ecosystem and meeting the requirements of sustainable environmental development.

[0025] 2. This invention uses a grouting molding method to prepare a hollow structure resembling a sea urchin shell. The structure has been verified by deep-sea high-pressure environment simulation test. Its high strength and pressure resistance ensure that the structure maintains its integrity for a long time under deep-sea isostatic pressure conditions, meeting the stringent requirements of deep-sea applications.

[0026] 3. This invention introduces a porous structure through the sacrificial template method, with a scientifically designed porosity and pore size that facilitates the entry and attachment of microorganisms. The surface-coated polymer coating (such as chitosan, gelatin, alginate, etc.) is tightly bonded to the ceramic matrix, providing a stable carbon source for microorganisms and significantly improving the bioattachment efficiency, thereby accelerating the restoration process of deep-sea habitats.

[0027] 4. This invention uses grouting molding and sacrificial template methods, which have simple process flow, easy parameter control, and low preparation cost. It is suitable for large-scale production and practical application and has good industrialization prospects.

[0028] 5. This invention combines the durability of ceramics with the stability of polymer coatings, enabling it to function effectively in deep-sea environments for extended periods, reducing replacement frequency, lowering maintenance costs, and providing sustainable support for deep-sea ecological restoration.

[0029] 6. By providing a rigid substrate and enhancing biological attachment capabilities, this invention effectively promotes the restoration of microbial and benthic communities in deep-sea mining areas, enhances biodiversity and ecosystem functions, supports the construction of deep-sea blue carbon ecosystems, and contributes to deep-sea environmental protection.

[0030] In summary, this invention overcomes the shortcomings of low bioattachment efficiency of ceramic culture media and insufficient stability of polymer materials in existing technologies through innovative material design and preparation methods. It provides an efficient, environmentally friendly, and economical solution for habitat restoration in deep-sea polymetallic nodule mining areas, and has significant application value and promotion potential. Attached Figure Description

[0031] Figure 1 This is a structural design diagram of the ceramic-polymer composite culture medium for habitat remediation in deep-sea polymetallic nodule mining areas according to Embodiment 1 of the present invention. Wherein: 1. Front view; 2. Cross-sectional view; 3. Through-holes; 4. Sea urchin-shell-shaped ceramic substrate; 5. Polymer coating; 6. Top view; 7. Isometric projection. Detailed Implementation

[0032] The technical solution of the present invention will be further explained and described below with reference to specific embodiments and accompanying drawings.

[0033] Example 1

[0034] (1) After mixing natural clay (mainly clay) and bamboo charcoal (25wt%) evenly, place it in a plaster mold, heat it to 1050℃ for 6 hours, keep it warm and sinter for 1 hour, then clean it with 5% hydrochloric acid solution for 10 minutes by ultrasonic cleaning, and then dry it to obtain the ceramic culture medium blank.

[0035] (2) The ceramic culture medium preform obtained in step (1) was immersed in a 1 wt% chitosan acetic acid solution, then removed and air-dried naturally. It was then immersed in a 0.01 mol / L ferrous sulfate aqueous solution for a cross-linking reaction for 4 hours, and finally dried to obtain the following result: Figure 1 The ceramic-polymer composite culture medium for habitat remediation in deep-sea polymetallic nodule mining areas, shown below, has a strength of 40-50 MPa. Deep-sea high-pressure environment simulation tests were conducted on it, and the experimental parameters during the test are shown in the table below.

[0036]

[0037] After undergoing the aforementioned deep-sea high-pressure environment simulation test, its structure remained intact without any defects, and its pressure resistance is suitable for deep-sea environments. The polymer coating (chitosan) did not undergo structural deformation or peeling under the simulated autoclave test conditions, and the coating remained stable as observed in images collected by the submersible after 60 days of sea trials.

[0038] Example 2

[0039] (1) After mixing natural clay (mainly clay) and bamboo charcoal (20wt%) evenly, place it in a plaster mold, heat it to 1050℃ for 6 hours, keep it at the temperature for 1 hour, and then clean it with 5% hydrochloric acid solution for 10 minutes by ultrasonic cleaning and drying to obtain the ceramic culture medium blank.

[0040] (2) The ceramic culture medium blank obtained in step (1) was immersed in a 1 wt% alginic acid solution and the pH value was adjusted to 7.0. Then it was taken out and air-dried naturally. Then it was immersed in a 0.02 mol / L calcium chloride aqueous solution for cross-linking reaction for 4 hours and then dried to obtain a ceramic polymer composite culture medium for habitat restoration in deep-sea polymetallic nodule mining areas with a strength of 40-50 MPa. It was subjected to deep-sea high pressure environment simulation test. The experimental parameters in the test process were the same as in Example 1. After the deep-sea high pressure environment simulation test, the sample structure remained intact and no defects were generated. Its pressure resistance was suitable for deep-sea environment and the polymer coating (alginic acid) remained stable.

[0041] Example 3

[0042] (1) After mixing natural clay (mainly clay) and bamboo charcoal (20wt%) evenly, place it in a plaster mold, heat it to 1050℃ for 6 hours, keep it at the temperature for 1 hour, and then clean it with 5% hydrochloric acid solution for 10 minutes by ultrasonic cleaning and drying to obtain the ceramic culture medium blank.

[0043] (2) The ceramic culture medium blank obtained in step (1) was immersed in a gelatin solution with a concentration of 1 wt%, and the pH value was adjusted to 7.0. Then it was taken out and air-dried naturally, and then immersed in a 0.005 mol / L manganese chloride aqueous solution for cross-linking reaction for 4 h. Then it was dried to obtain a ceramic polymer composite culture medium for habitat restoration in deep-sea polymetallic nodule mining areas with a strength of 40-50 MPa. It was subjected to deep-sea high pressure environment simulation test. The experimental parameters in the test process were the same as in Example 1. After the deep-sea high pressure environment simulation test, the sample structure remained intact and no defects were generated. Its pressure resistance was suitable for deep-sea environment; the polymer coating (gelatin) remained stable.

[0044] Example 4

[0045] (1) After mixing natural red clay (mainly clay with 1 wt% iron) with bamboo charcoal (25 wt%) evenly, place it in a plaster mold, heat it to 1100℃ for 5 hours, keep it warm and sinter for 1 hour, then clean it with 5% hydrochloric acid solution for 10 minutes by ultrasonic cleaning, and then dry it to obtain the ceramic culture medium blank.

[0046] (2) Same as Example 1, and the effect is also the same as Example 1.

[0047] Example 5

[0048] (1) Natural red clay (mainly clay with 1 wt% iron) and sawdust (25 wt% added) are mixed evenly and placed in a plaster mold. The temperature is raised to 1100℃ in 5 hours and sintered for 1 hour. After ultrasonic cleaning with 5% hydrochloric acid solution for 10 minutes, the ceramic culture medium blank is dried to obtain the ceramic culture medium blank.

[0049] (2) Same as Example 1, and the effect is also the same as Example 1.

[0050] The above description is merely a preferred embodiment of the present invention, and therefore should not be construed as limiting the scope of the present invention. All equivalent changes and modifications made in accordance with the scope of the patent and the contents of the specification should still fall within the scope of the present invention.

Claims

1. A ceramic-polymer composite culture medium for habitat remediation in deep-sea polymetallic nodule mining areas, characterized in that: It consists of a ceramic culture medium preform with a porosity of 10-40% and a polymer coating formed by cross-linking on the surface of the ceramic culture medium preform, wherein, The ceramic culture medium ligand is prepared by sacrificial template method from natural clay and pore-forming particles, with a pore size of 0.01-0.1 mm. The polymer coating material is selected from chitosan, gelatin and alginate.

2. The ceramic polymer composite culture medium for habitat remediation in deep-sea polymetallic nodule mining areas as described in claim 1, characterized in that: The natural clay is mainly composed of clay.

3. The ceramic polymer composite culture medium for habitat remediation in deep-sea polymetallic nodule mining areas as described in claim 1, characterized in that: The pore-forming particles are selected from wood chips, bamboo charcoal, starch, and straw.

4. The ceramic polymer composite culture medium for habitat remediation in deep-sea polymetallic nodule mining areas as described in claim 3, characterized in that: The amount of the pore-forming particles added is 20-60 wt%.

5. The method for preparing the ceramic polymer composite culture medium for habitat remediation in deep-sea polymetallic nodule mining areas as described in any one of claims 1 to 4, characterized in that: Includes the following steps: (1) The natural clay and the pore-forming particles are mixed evenly and placed in a mold. The temperature is raised to 1050-1100℃ in 5-6 hours and sintered for 0.8-1.2 hours. After cleaning, the ceramic culture medium blank is obtained. (2) The ceramic culture medium blank obtained in step (1) is immersed in an aqueous solution of polymer material monomer, then taken out and air-dried, then immersed in the corresponding divalent metal ion solution for cross-linking reaction, and then dried to obtain the product.

6. The preparation method according to claim 5, characterized in that: The cleaning in step (1) is performed by ultrasonic cleaning using a 4-5% hydrochloric acid solution.

7. The preparation method according to claim 5, characterized in that: The concentration of the polymer monomer aqueous solution in step (2) is 1-5 wt%.

8. The preparation method according to claim 6, characterized in that: The solute in the divalent metal ion solution in step (2) is selected from ferrous sulfate, calcium chloride and manganese chloride, with a concentration of 0.005-0.01 mol / L.

9. The preparation method according to claim 8, characterized in that: The cross-linking reaction in step (2) takes 2-4 hours.

10. The preparation method according to claim 5, characterized in that: The mold used in step (1) is a plaster mold.

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