Pristis gigantea and method for leaching rare earth elements from waste material thereof

Abstract

The present application relates to the field of environment-friendly biological rare earth recovery technology, and particularly relates to a Priestia megaterium MeR-2 and a method for leaching rare earth elements from waste materials. Specifically, the present application provides a method for leaching rare earth elements from waste materials by using microorganisms and their metabolites, which solves the problems of large amount of chemical reagents, high production cost, serious environmental pollution and the like in the process of chemical leaching of rare earth waste materials. The strain provided by the present application has low cultivation cost, fast growth speed, simple leaching conditions, and has leaching capacity for rare earth ions in various waste materials, and has good application prospect in the aspects of microbial recovery and reuse of rare earth waste materials.

Description

Technical Field

[0001] This invention relates to the field of environmentally friendly biological rare earth recycling technology, and in particular to a method for extracting rare earth elements from *Pristiria megaterium* and its leaching waste. Background Technology

[0002] Rare earth elements, including fifteen lanthanides and scandium and yttrium, are known as "industrial gold" due to their crucial applications in high-tech fields and cutting-edge research. Because these elements have limited reserves and uneven geographical distribution, extracting rare earth elements from secondary resources is becoming increasingly important, especially given the growing demand in areas such as permanent magnet materials and industrial catalysts.

[0003] Currently, conventional methods for extracting rare earth elements from urban mineral deposits mainly rely on physicochemical leaching techniques using strong acids and organic solvents. These traditional methods are not only complex and energy-intensive, but also potentially cause serious environmental pollution. Therefore, it is urgent to develop a new, environmentally friendly, and efficient leaching technology to achieve high leaching rates while minimizing environmental impact.

[0004] Bioleaching, a method utilizing microorganisms to extract rare earth elements, offers an environmentally friendly alternative. This method primarily releases rare earth elements from a solid matrix through organic acids, such as citric acid and lactic acid, produced by heterotrophic bacteria or fungi. However, existing commercially available microorganisms, such as yeast and *Glucosobacterium oxysporum*, exhibit low efficiency and slow processes in extracting rare earth elements from spent FCC catalysts and NdFeB magnets, mainly due to their poor tolerance to high concentrations of rare earth ions. Therefore, screening and cultivating potent microbial communities from rare earth mines and waste materials is crucial for improving the efficiency of rare earth bioleaching. However, reports on the application of these specialized microorganisms remain limited. Therefore, providing a novel *Pristiria megaterium* strain capable of efficiently leaching rare earth ions from waste materials could offer a new option and pathway for biometallurgy, possessing significant practical implications. Summary of the Invention

[0005] In view of this, the present invention provides a method for leaching rare earth elements from waste using microorganisms and their metabolites, which solves the problems of large chemical reagent consumption, high production costs, and serious environmental pollution in the chemical leaching process of rare earth waste.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0007] In a first aspect, the present invention provides Priestia megaterium MeR-2, characterized in that its accession number is CGMCC No. 30398.

[0008] Secondly, the present invention also provides a method for culturing the aforementioned Priestia megaterium MeR-2, wherein the Priestia megaterium MeR-2 is picked and cultured for 2-4 days at 30°C and 200 rpm in Luria-Bertani liquid medium supplemented with 60 g / L glucose or in nutrient-deficient Luria-Bertani liquid medium supplemented with 60 g / L glucose;

[0009] In the nutrient-deficient Luria-Bertani liquid medium, the original components of the LB medium account for 0.05% to 50%.

[0010] Thirdly, the present invention also provides one or more of the inactivated bacterial cells, exosomes, or metabolites of the aforementioned Priestia megaterium MeR-2.

[0011] Fourthly, the present invention also provides a method for preparing the metabolites of *Priestia megaterium* MeR-2, wherein *Priestia megaterium* MeR-2 is picked and cultured in Luria-Bertani liquid medium supplemented with 60 g / L glucose or in nutrient-deficient Luria-Bertani liquid medium supplemented with 60 g / L glucose at 30°C and 200 rpm for 2 to 4 days, the culture medium is collected and centrifuged at 8000 rpm for 5 min, and the supernatant is collected;

[0012] In the nutrient-deficient Luria-Bertani liquid medium, the original components of the LB medium account for 0.05% to 50%.

[0013] Fifthly, the present invention also provides metabolites obtained by the preparation method described above.

[0014] In a sixth aspect, the present invention also provides the application of any of the following in rare earth elements in leaching waste;

[0015] (I) The aforementioned Priestia megaterium MeR-2;

[0016] (II) One or more of the inactivated bacterial cells, exosomes or metabolites mentioned above;

[0017] (III) The metabolites mentioned above.

[0018] In some specific embodiments of the present invention, the waste includes one or more of waste FCC catalyst, waste NdFeB sludge, or waste NdFeB powder.

[0019] In some specific embodiments of the present invention, the main framework of the spent FCC catalyst is aluminosilicate, containing rare earth elements and / or transition elements, wherein the content of the rare earth elements and / or transition elements is 0.01% to 10%; the rare earth elements include, but are not limited to, lanthanum and / or cerium; the transition elements include, but are not limited to, nickel and / or vanadium.

[0020] The main component of the waste NdFeB sludge is NdFeB (N2Fe). 14 B) Magnets containing 1% to 30% lubricating oil;

[0021] The main component of the waste NdFeB powder is NdFeB (Nd2Fe). 14 B) Originates from various stages of industrial production of NdFeB magnets, including cutting, molding, or sintering processes.

[0022] In a seventh aspect, the present invention also provides an article of manufacture comprising any one of the following:

[0023] (I) The aforementioned Priestia megaterium MeR-2;

[0024] (II) One or more of the inactivated bacterial cells, exosomes or metabolites mentioned above;

[0025] (III) The aforementioned metabolites;

[0026] The products include microecological products, probiotic products, synbiotic products and / or postbiotic products.

[0027] Eighthly, the present invention also provides a method for leaching rare earth elements from leaching waste, comprising mixing any one of the following with the waste and incubating it;

[0028] (I) The aforementioned Priestia megaterium MeR-2;

[0029] (II) One or more of the inactivated bacterial cells, exosomes or metabolites mentioned above;

[0030] (III) The aforementioned metabolites;

[0031] (IV) The aforementioned product.

[0032] In some specific embodiments of the present invention, the waste includes one or more of waste FCC catalyst, waste NdFeB sludge, or waste NdFeB powder;

[0033] Preferably, the main framework of the spent FCC catalyst is aluminosilicate, containing rare earth elements and / or transition elements, wherein the content of the rare earth elements and / or transition elements is 0.01% to 10%; the rare earth elements include, but are not limited to, lanthanum and / or cerium; the transition elements include, but are not limited to, nickel and / or vanadium.

[0034] The main component of the waste NdFeB sludge is NdFeB (N2Fe). 14 B) Magnets containing 1% to 30% lubricating oil;

[0035] The main component of the waste NdFeB powder is NdFeB (Nd2Fe). 14 B) Originates from various stages of industrial production of NdFeB magnets, including cutting, molding, or sintering processes.

[0036] Preferably, the liquid-to-solid ratio of the Priestia megaterium MeR-2 to the spent FCC catalyst is 1:(2-500);

[0037] The liquid-to-solid ratio of the Priestia megaterium MeR-2 to the waste NdFeB sludge is 1:(4-500);

[0038] The liquid-to-solid ratio of the Priestia megaterium MeR-2 to the waste NdFeB powder is 1:(4-500);

[0039] Preferably, the liquid-to-solid ratio of the metabolite to the spent FCC catalyst is 1:(2-500);

[0040] The liquid-to-solid ratio of the metabolites to the waste NdFeB sludge is 1:50.

[0041] The liquid-to-solid ratio of the metabolite to the waste NdFeB powder is 1:50.

[0042] Preferably, the incubation conditions are 30°C and 200 rpm for 2 to 8 days.

[0043] This invention provides a method for leaching rare earth elements from waste using microorganisms and their metabolites, solving problems such as large amounts of chemical reagents, high production costs, and severe environmental pollution associated with the chemical leaching of rare earth waste. The strains provided in this invention have low cultivation costs, rapid growth rates, and simple leaching conditions, and are capable of leaching rare earth ions from various types of waste, showing promising application prospects in the microbial recycling and reuse of rare earth waste.

[0044] Biological Preservation Instructions

[0045] Strain: MER-2; deposit date: April 22, 2024; deposit number: CGMCC No. 30398; classification name: Priestia megaterium; depositary institution: China General Microbiological Culture Collection Center; depositary address: Institute of Microbiology, Chinese Academy of Sciences, No. 3, No. 1 Beichen West Road, Chaoyang District, Beijing. Detailed Implementation

[0046] This invention discloses a method for utilizing rare earth elements from *Pristiria megaterium* and its leaching waste. Those skilled in the art can refer to this document and appropriately modify the process parameters to achieve the same result. It is particularly important to note that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in this invention. The methods and applications of this invention have been described through preferred embodiments. Those skilled in the art can clearly modify or appropriately change and combine the methods and applications described herein without departing from the content, spirit, and scope of this invention to realize and apply the technology of this invention.

[0047] The present invention adopts the following technical solution:

[0048] (1) Screening of mineral leaching strains: Strains were screened using silica-solubilizing medium solid plates. Priestia megaterium MeR-2 (CGMCC No. 30398), which could produce obvious silica-solubilizing transparent rings on silica-solubilizing medium solid plates, was selected for further study.

[0049] (2) Microbial culture: The giant Pristilia MeR-2 was cultured at 30°C and 200 rpm for 2-4 days in Luria-Bertani (LB) liquid medium supplemented with 60 g / L glucose or in nutrient-deficient Luria-Bertani (LB) liquid medium supplemented with 60 g / L glucose (the original component content of LB medium was 0.05-50%).

[0050] (3) Co-cultivation of rare earth elements in waste FCC catalyst (the main framework is aluminosilicate, containing rare earth elements such as lanthanum and cerium, as well as transition elements such as nickel and vanadium, with a content of 0.01%-10%): The waste FCC catalyst was co-incubated with *Pristiria megaterium* MeR-2 in Luria-Bertani (LB) liquid medium with 60 g / L glucose or in nutrient-deficient Luria-Bertani (LB) liquid medium with 60 g / L glucose (the original component content of LB medium is 0.05-50%) at a solid-liquid ratio of 1:2-1:500 and cultured at 30℃ and 200 rpm for 2-4 days.

[0051] (4) Co-cultivation and leaching of waste NdFeB sludge (main component is NdFeB (Nd2Fe) 14 B) Rare earth elements in magnets (containing 1%-30% lubricating oil): *Pristiria megaterium* MeR-2 was co-incubated with waste NdFeB sludge at a solid-liquid ratio of 1:4-1:500 in Luria-Bertani (LB) liquid medium supplemented with 60 g / L glucose or in a nutrient-deficient Luria-Bertani (LB) liquid medium supplemented with 60 g / L glucose (the original component content of the LB medium was 0.05-50%). The culture was carried out at 30°C and 200 rpm for 2-8 days.

[0052] (5) Co-cultivation and leaching of waste NdFeB powder (main component is NdFeB (Nd2Fe) 14 B) Rare earth elements generated in various stages of industrial NdFeB magnet production, such as cutting, molding, and sintering processes: *Pristiria megaterium* MeR-2 is co-incubated with waste NdFeB sludge at a liquid-to-solid ratio of 1:4 to 1:500 using either Luria-Bertani (LB) liquid medium supplemented with 60 g / L glucose or nutrient-deficient Luria-Bertani (LB) liquid medium supplemented with 60 g / L glucose (the original component content of the LB medium is 0.05-50%). The culture is carried out at 30°C and 200 rpm for 2-8 days.

[0053] (6) Preparation of microbial culture metabolites: Centrifuge the microbial culture medium from step (2) at 8000 rpm for 5 min and collect the supernatant.

[0054] (7) Leaching of rare earth elements from waste FCC catalyst (the main framework is aluminosilicate, containing rare earth elements such as lanthanum and cerium, as well as transition elements such as nickel and vanadium, with a content of 0.01%-10%) from microbial culture metabolites: Dilute the supernatant of the leachate in step (5) with ultrapure water (minimum supernatant content 2%), then mix the original solution or diluted solution with the waste FCC catalyst at a solid-liquid ratio of 1:2-1:500, and leach at 30℃ and 200rpm for 2-4 days to obtain the leachate.

[0055] (8) Leaching of waste NdFeB sludge from microbial culture metabolites (main component is NdFeB (Nd2Fe) 14 B) Rare earth elements in magnets containing 1%-30% lubricating oil: Dilute the supernatant of the leachate in step (5) with ultrapure water (minimum supernatant content 2%), mix the original solution or diluted solution with waste NdFeB sludge at a solid-liquid ratio of 1:50, leach at 30°C and 200 rpm, and obtain leachate after 2 days.

[0056] (9) Leaching of waste NdFeB powder from microbial culture metabolites (main component is NdFeB (Nd2Fe) 14 B), rare earth elements generated in various stages of industrial production of NdFeB magnets, such as cutting, molding, sintering, etc.: dilute the supernatant of the leachate in step (5) with ultrapure water (minimum supernatant content 2%), mix the original solution or diluted solution with waste NdFeB sintering or molding powder at a solid-liquid ratio of 1:50, leach at 30°C and 200 rpm, and obtain leachate after 2 days.

[0057] (10) The leaching capacity of MeR-2 was determined by detecting the content and type of rare earth elements in steps (3)(4)(5)(7)(8)(9) using ICP-OES and ICP-MS.

[0058] The strain provided by this invention has low cultivation cost, fast growth rate, simple leaching conditions, and the ability to leach rare earth ions from various wastes. It has good application prospects in the microbial recycling and reuse of rare earth waste.

[0059] The raw materials and reagents used in the method for extracting rare earth elements from *Pristiria gigantea* and its leaching waste provided by this invention are all commercially available.

[0060] The present invention will be further illustrated below with reference to the embodiments:

[0061] Example 1: Screening of rare earth leaching strains and determination of their ability to dissolve insoluble silicates

[0062] A single colony of purified *Priestia megaterium* MeR-2 was picked from LB solid medium containing 1.5-3% agar and added to 4 mL of LB liquid medium. The culture was incubated overnight at 30°C and 200 rpm in a constant temperature shaking incubator. 2 μL of the bacterial culture was then added to a silica-dissolving solid culture plate. After ten days of incubation, the results were observed and recorded. The appearance of a clear ring was recorded as a positive result, indicating that the strain has the ability to dissolve insoluble silicates. The culture was then biologically preserved and the preservation number was CGMCC No. 30398.

[0063] Example 2: Rare earth elements in waste FCC catalyst leaching by MeR-2 microbial co-culture

[0064] A single colony of purified MeR-2 (CGMCC No. 30398) was picked from LB solid medium containing 1.5-3% agar and transferred to 4 mL of LB liquid medium. The culture was incubated overnight at 30°C and 200 rpm in a shaker until the OD value reached 0.8-1.2, serving as the seed culture. 1% (v / v) of the seed culture (final OD value 0.008-0.012) was inoculated into LB liquid medium containing 60 g / L glucose. This medium contained spent FCC catalyst (main framework of aluminosilicate, containing rare earth elements such as lanthanum and cerium, and transition elements such as nickel and vanadium, at a solid-liquid ratio of 1:2-1:500, with a content of 0.01%-10%). The culture was incubated at 30°C and 200 rpm in a shaker for 2-4 days. The supernatant was collected by centrifugation at 8000 rpm for 5 min.

[0065] After the solution becomes clear and transparent, dilute and bring to a final volume to achieve a target element content of 1 ppb-10 ppm. Then, perform quantitative analysis of rare earth elements using ICP-OES and ICP-MS (determined according to the national standard GB / T18115-2021, Chemical Analysis Methods for Rare Earth Impurities in Rare Earth Metals and Their Oxides).

[0066] Table 1

[0067] solid-liquid ratio Leaching rate (%) 1:2 32.57917555 1:5 41.99451777 1:10 53.43641953 1:50 58.01421873 1:100 70.7524405 1:500 98.57917555

[0068] Example 3: Rare earth elements in waste FCC catalyst leaching using MeR-2 microbial co-culture

[0069] A single purified MeR-2 colony (CGMCC No. 30398) was picked from LB solid medium containing 1.5-3% agar and transferred to 4 mL of LB liquid medium. The culture was incubated overnight at 30°C and 200 rpm in a shaker until the OD value reached 0.8-1.2, serving as the seed culture. A 1% (v / v) portion of the seed culture (final OD value 0.008-0.012) was inoculated into a nutrient-deficient Luria-Bertani (LB) liquid medium supplemented with 60 g / L glucose (the original LB medium composition was 0.05-50%) containing spent FCC catalyst (main framework of aluminosilicate, containing rare earth elements such as lanthanum and cerium, and transition elements such as nickel and vanadium, at a liquid-to-solid ratio of 1:2-1:500, at a concentration of 0.01%-10%). The culture was incubated at 30°C and 200 rpm in a shaker for 2-4 days. The supernatant was collected by centrifugation at 8000 rpm for 5 min.

[0070] Example 4: MeR-2 co-cultivation for leaching rare earth elements from waste NdFeB sludge

[0071] A single purified MeR-2 colony (CGMCC No. 30398) was picked from LB solid medium containing 1.5-3% agar and transferred to 4 mL of LB liquid medium. The culture was incubated overnight at 30°C and 200 rpm in a shaker until the OD value reached 0.8-1.2, serving as the seed culture. A 1% (v / v) portion of the seed culture (final OD value 0.008-0.012) was inoculated into LB liquid medium containing 60 g / L glucose. This medium also contained waste NdFeB sludge (mainly composed of NdFeB) with a liquid-to-solid ratio of 1:4-1:500. 14 B) Magnets containing 1%-30% lubricating oil. Incubate at 30℃ and 200rpm in a constant temperature shaking incubator for 2-8 days. Collect the supernatant by centrifugation at 8000rpm for 5 minutes.

[0072] Example 5: MeR-2 co-cultivation for leaching rare earth elements from waste NdFeB sludge

[0073] A purified single colony of MeR-2 (CGMCC No. 30398) was picked from LB solid medium containing 1.5-3% agar and transferred to 4 mL of LB liquid medium. The culture was incubated overnight at 30°C and 200 rpm in a shaker until the OD value reached 0.8-1.2, serving as the seed culture. A 1% (v / v) portion of the seed culture (final OD value 0.008-0.012) was inoculated into a nutrient-deficient Luria-Bertani (LB) liquid medium supplemented with 60 g / L glucose (the original LB medium composition was 0.05-50%) containing waste NdFeB sludge (mainly composed of Nd2Fe) at a liquid-to-solid ratio of 1:4-1:500. 14 B) Magnets containing 1%-30% lubricating oil. Incubate at 30℃ and 200rpm in a constant temperature shaking incubator for 2-8 days. Collect the supernatant by centrifugation at 8000rpm for 5 minutes.

[0074] Example 6: Rare earth elements in waste NdFeB powder co-cultured and leached using MeR-2

[0075] A single purified MeR-2 colony (CGMCC No. 30398) was picked from LB solid medium containing 1.5-3% agar and transferred to 4 mL of LB liquid medium. The culture was incubated overnight at 30°C and 200 rpm in a shaker until the OD value reached 0.8-1.2, serving as the seed culture. A 1% (v / v) portion of the seed culture (final OD value 0.008-0.012) was inoculated into LB liquid medium containing 60 g / L glucose. This medium contained waste NdFeB powder (mainly Nd2Fe) at a liquid-to-solid ratio of 1:4-1:500. 14B), generated in various stages of industrial NdFeB magnet production, such as cutting, molding, and sintering processes. Incubate at 30℃ and 200rpm in a constant-temperature shaking incubator for 2-8 days. Collect the supernatant by centrifugation at 8000rpm for 5 minutes.

[0076] Example 7: Rare earth elements in waste NdFeB powder co-cultured and leached using MeR-2.

[0077] A single purified MeR-2 colony (CGMCC No. 30398) was picked from LB solid medium containing 1.5-3% agar and transferred to 4 mL of LB liquid medium. The culture was incubated overnight at 30°C and 200 rpm in a shaker until the OD value reached 0.8-1.2, serving as the seed culture. A 1% (v / v) portion of the seed culture (final OD value 0.008-0.012) was inoculated into a nutrient-deficient Luria-Bertani (LB) liquid medium supplemented with 60 g / L glucose (the original LB medium composition was 0.05-50%) containing waste NdFeB powder (main component being Nd2Fe) at a liquid-to-solid ratio of 1:4-1:500. 14 B), generated in various stages of industrial NdFeB magnet production, such as cutting, molding, and sintering processes. Incubate at 30℃ and 200rpm in a constant-temperature shaking incubator for 2-8 days. Collect the supernatant by centrifugation at 8000rpm for 5 minutes.

[0078] Example 8: Preparation of MeR-2 microbial extract

[0079] A single colony of purified MeR-2 (CGMCC No. 30398) was picked from LB solid medium containing 1.5-3% agar and added to 4 mL of LB liquid medium. The culture was incubated overnight at 30°C with a shaking incubator at 200 rpm until an OD value of 0.8-1.2 was reached, serving as the seed culture. A 1% (v / v) portion of the seed culture (final OD value 0.008-0.012) was inoculated into Luria-Bertani (LB) liquid medium supplemented with 60 g / L glucose and incubated at 30°C with a shaking incubator at 200 rpm until the logarithmic growth phase. The supernatant was collected by centrifugation at 8000 rpm for 5 min.

[0080] Example 9: Preparation of MeR-2 microbial extract

[0081] A single colony of purified MeR-2 (CGMCC No. 30398) was picked from LB solid medium containing 1.5-3% agar and transferred to 4 mL of LB liquid medium. The culture was incubated overnight at 30°C with a shaking incubator at 200 rpm until an OD value of 0.8-1.2 was reached, serving as the seed culture. A 1% (v / v) portion of the seed culture (final OD value 0.008-0.012) was inoculated into nutrient-deficient Luria-Bertani (LB) liquid medium (original LB medium composition 0.05-50%) and incubated at 30°C with a shaking incubator at 200 rpm until the logarithmic growth phase. The supernatant was collected by centrifugation at 8000 rpm for 5 min.

[0082] Example 10: Leaching rare earth elements from FCC using MeR-2 microbial culture supernatant

[0083] The original or diluted supernatant of the microbial culture from Example 8 (diluted with ultrapure water, with a minimum supernatant content of 2%) was added to the waste FCC catalyst (the main framework is aluminosilicate, containing rare earth elements such as lanthanum and cerium, as well as transition elements such as nickel and vanadium, with a content of 0.01%-10%), and mixed at a liquid-to-solid ratio of 1:2-1:500. The mixture was placed in a constant temperature shaking incubator at 30°C and 200 rpm, and the leachate was obtained after 2 days.

[0084] Example 11: Leaching rare earth elements from waste NdFeB sludge using MeR-2 microbial culture supernatant

[0085] The original or diluted supernatant of the microbial culture from Example 8 (diluted with ultrapure water, minimum supernatant content 2%) was added to waste NdFeB sludge (the main component of which is NdFeB). 14 B) Mix the magnet (containing 1%-30% lubricating oil) with a liquid-solid ratio of 1:2-1:500, place it in a constant temperature shaking incubator at 30℃ and 200rpm, and obtain the leachate after 2 days.

[0086] Example 12: Leaching rare earth elements from waste NdFeB powder using MeR-2 microbial culture supernatant.

[0087] The original or diluted supernatant of the microbial culture from Example 8 (diluted with ultrapure water, minimum supernatant content 2%) was added to waste NdFeB powder (the main component of which is NdFeB (Nd2Fe)). 14 B), produced in various stages of industrial production of NdFeB magnets, such as cutting, molding, sintering, etc., is mixed in a liquid-to-solid ratio of 1:2-1:500 and placed in a constant temperature shaking incubator at 30℃ and 200rpm for 2 days to obtain the leachate.

[0088] Example 13: Leaching rare earth elements from FCC using MeR-2 microbial culture supernatant

[0089] The original or diluted supernatant of the microbial culture from Example 9 (diluted with ultrapure water, with a minimum supernatant content of 2%) was added to the waste FCC catalyst (the main framework is aluminosilicate, containing rare earth elements such as lanthanum and cerium, as well as transition elements such as nickel and vanadium, with a content of 0.01%-10%), and mixed at a liquid-to-solid ratio of 1:2-1:500. The mixture was placed in a constant temperature shaking incubator at 30°C and 200 rpm, and the leachate was obtained after 2 days.

[0090] Example 14: Leaching rare earth elements from waste NdFeB sludge using MeR-2 microbial culture supernatant.

[0091] The original or diluted supernatant of the microbial culture from Example 9 (diluted with ultrapure water, minimum supernatant content 2%) was added to waste NdFeB sludge (the main component of which is NdFeB). 14 B) Mix the magnet (containing 1%-30% lubricating oil) with a liquid-solid ratio of 1:2-1:500, place it in a constant temperature shaking incubator at 30℃ and 200rpm, and obtain the leachate after 2 days.

[0092] Example 15: Leaching rare earth elements from waste NdFeB powder using MeR-2 microbial culture supernatant.

[0093] The original or diluted supernatant of the microbial culture from Example 9 (diluted with ultrapure water, minimum supernatant content 2%) was added to waste NdFeB powder (the main component of which is NdFeB (Nd2Fe)). 14 B), produced in various stages of industrial production of NdFeB magnets, such as cutting, molding, sintering, etc., is mixed in a liquid-to-solid ratio of 1:2-1:500 and placed in a constant temperature shaking incubator at 30℃ and 200rpm for 2 days to obtain the leachate.

[0094] Example 16: Detection of the leaching capacity of MeR-2 by ICP-MS

[0095] The leachates from Examples 2-7 and 10-15 were filtered through a 0.22 μm needle filter membrane, and the filtrate was collected. Digestion was performed using a nitric acid-perchloric acid (10:1) mixed acid system on a 210°C hot plate. After the solution became clear and transparent, it was diluted to a final volume to achieve a target element concentration of 1 ppb-10 ppm. Quantitative analysis of rare earth elements was then performed using ICP-OES and ICP-MS (determined according to the national standard GB / T 18115-2021, Chemical Analysis Methods for Rare Earth Impurities in Rare Earth Metals and Their Oxides). The experimental results are shown in Tables 2-4.

[0096] Table 2. Leaching amount of rare earth elements from spent FCC catalyst by strain MeR-2

[0097]

[0098] Among Examples 2, 3, 10, and 13, there were significant differences in the leaching rates of La and Ce. Example 13 showed the best leaching effect, with a leaching rate of 95.78% for La and 96.66% for Ce.

[0099] Table 3. Leaching amount of rare earth elements from waste NdFeB sludge by the MeR-2 strain.

[0100]

[0101]

[0102] Among Examples 4, 5, 11, and 14, the leaching rates of Pr, Nd, Gd, Tb, and Dy showed significant differences between 4(A), 11(B) and 5(C), 14(C), but no significant differences were found among 5(C) and 14(C). Example 4 exhibited the best leaching effect, with leaching rates of Pr (97.73%), Nd (98.09%), Gd (97.86%), Tb (98.00%), and Dy (97.93%).

[0103] Table 4. Leaching amount of rare earth elements from waste NdFeB powder by strain MeR-2

[0104]

[0105] Among Examples 6, 12, 15, and 7, the leaching rates of Pr, Nd, Gd, Tb, and Dy showed significant differences between 7(A), 6(B) and 12(C), 15(C), but no significant differences were found among 12(C) and 15(C). Example 7 exhibited the best leaching effect, with leaching rates of Pr (97.92%), Nd (97.85%), Gd (97.87%), Tb (97.84%), and Dy (98.01%).

[0106] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. Pristiria megaterium ( Priestia megaterium MeR-2, characterized in that, Its accession number is CGMCC No.30398.

2. The Pristiria megagenes as described in claim 1 ( Priestia megaterium The method for culturing MeR-2 is characterized by, Pick the aforementioned Pristilia megaterium ( Priestia megaterium MeR-2 was cultured for 2-4 days at 30 ºC and 200 rpm in Luria-Bertani liquid medium supplemented with 60 g / L glucose or in nutrient-deficient Luria-Bertani liquid medium supplemented with 60 g / L glucose. In the nutrient-deficient Luria-Bertani liquid medium, the original components of the LB medium account for 0.05-50%.

3. The Pristiria megagenes as described in claim 1 ( Priestia megaterium The method for preparing the supernatant of MeR-2 is characterized in that, Pick the aforementioned Pristilia megaterium ( Priestia megaterium MeR-2 was cultured in Luria-Bertani liquid medium supplemented with 60 g / L glucose or in nutrient-deficient Luria-Bertani liquid medium supplemented with 60 g / L glucose at 30 ºC and 200 rpm for 2-4 days. The culture medium was then collected and centrifuged at 8000 rpm for 5 min, and the supernatant was collected. In the nutrient-deficient Luria-Bertani liquid medium, the original components of the LB medium account for 0.05-50%.

4. The supernatant obtained by the preparation method as described in claim 3.

5. The application of any of the following in the use of rare earth elements in leaching waste; (I) *Pristeia giantiformis* as described in claim 1 ( Priestia megaterium MeR-2; (II) The supernatant as described in claim 4; The waste includes one or more of the following: waste FCC catalyst, waste NdFeB sludge, or waste NdFeB powder; The main framework of the spent FCC catalyst is aluminosilicate, containing rare earth elements and / or transition elements, with the content of rare earth elements and / or transition elements being 0.01% to 10%; the rare earth elements include lanthanum and / or cerium; the transition elements include nickel and / or vanadium. The main component of the waste NdFeB sludge is NdFeB (N2Fe). 14 B) Magnets containing 1% to 30% lubricating oil; The main component of the waste NdFeB powder is NdFeB (Nd2Fe). 14 B), which arises from various stages of industrial production of NdFeB magnets, including cutting, molding, or sintering processes.

6. A method for leaching rare earth elements from waste, characterized in that, Mix any of the following with the waste and incubate; (I) *Pristeia giantiformis* as described in claim 1 ( Priestia megaterium MeR-2; (II) The supernatant as described in claim 4; The waste includes one or more of the following: waste FCC catalyst, waste NdFeB sludge, or waste NdFeB powder; The main framework of the spent FCC catalyst is aluminosilicate, containing rare earth elements and / or transition elements, with the content of rare earth elements and / or transition elements being 0.01% to 10%; the rare earth elements include lanthanum and / or cerium; the transition elements include nickel and / or vanadium. The main component of the waste NdFeB sludge is NdFeB (N2Fe). 14 B) Magnets containing 1% to 30% lubricating oil; The main component of the waste NdFeB powder is NdFeB (Nd2Fe). 14 B), which arises from various stages of industrial production of NdFeB magnets, including cutting, molding, or sintering processes.

7. The method as described in claim 6, characterized in that, The giant Pristiia ( Priestia megaterium The liquid-to-solid ratio of MeR-2 to the spent FCC catalyst is 1:(2~500).

8. The method as described in claim 6, characterized in that, The giant Pristiia ( Priestia megaterium The liquid-solid ratio of MeR-2 to the waste NdFeB sludge is 1:(4~500).

9. The method as described in claim 6, characterized in that, The giant Pristiia ( Priestia megaterium The liquid-solid ratio of MeR-2 to the waste NdFeB powder is 1:(4~500).

10. The method as described in claim 6, characterized in that, The liquid-to-solid ratio of the supernatant to the spent FCC catalyst is 1:(2~500).

11. The method as described in claim 6, characterized in that, The liquid-to-solid ratio of the supernatant to the waste NdFeB sludge is 1:

50.

12. The method as described in claim 6, characterized in that, The liquid-to-solid ratio of the supernatant to the waste NdFeB powder is 1:

50.

13. The method as described in claim 6, characterized in that, The incubation conditions are 30 ºC and 200 rpm for 2 to 8 days.

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