Industrial carbon capture environment-friendly process using plant fusion enzyme

Abstract

The invention belongs to the technical field of carbon dioxide trapping processes, and particularly relates to an environment-friendly industrial carbon trapping process using plant fusion enzyme, which comprises the following steps: S1, immobilizing carbonic anhydrase through electrostatic interaction by using ferroferric oxide as a carrier and relying on mesoporous material silicon oxide and utilizing a covalent binding and cross-linking method combined method, so as to obtain a plant fusion enzyme immobilized carbonic anhydrase; the immobilized heat-resistant and alkali-resistant carbonic anhydrase is prepared in a mode of fusing with elastin-like polypeptide; s2, fully fusing the immobilized heat-resistant alkali-resistant carbonic anhydrase and carboxylase to prepare a plant fusion enzyme; s3, carbon dioxide trapping is conducted through the plant fusion enzyme, plant fusion enzyme solutions of different concentrations are used according to different gas component contents of carbon dioxide trapping points, meanwhile, potassium carbonate of different proportions is matched, and carbon dioxide trapping can be completely environmentally friendly, low in cost, easy to implement, safe and reliable.

Description

Technical Field

[0001] The present invention belongs to the technical field of carbon dioxide capture technology, and in particular relates to an environmentally friendly industrial carbon capture process using plant fusion enzymes. Background Art

[0002] In the past 50 years, many methods of carbon dioxide capture have been demonstrated. Using plant enzymes from natural plants for capture is the most natural and environmentally friendly way. However, compared with the three mainstream capture methods in the current industrial environment: two aqueous washing processes and one solid adsorption process, natural plants have low capture efficiency and slow capture speed. Therefore, only by solving the capture efficiency and speed of natural plants can the most natural and environmentally friendly carbon dioxide capture be truly achieved. Carbonic anhydrase is one of the fastest-reacting enzymes on earth. It can greatly improve the efficiency of carbon dioxide capture and biomineralization, thereby effectively reducing the emission of carbon dioxide in the atmosphere. However, the capture process requires high temperature conditions, and the process of carbon dioxide biomineralization to form calcium carbonate requires alkaline conditions. Therefore, selecting and forming a stable thermophilic and alkali-resistant carbonic anhydrase through immobilization is the top priority of the carbon dioxide capture system. There are many selection and immobilization methods at present, and the carbonic anhydrase formed is also diverse, and the effects are also different. There are currently three mainstream capture methods in industrial environments: two aqueous washing processes and one solid adsorption process. Regardless of whether an alkaline solution, liquid amine solution or solid amine solution process is used, there is an inevitable process flow - high pressure and high energy consumption, and even a risk of severe toxicity. This is bound to solve the carbon capture problem while creating new environmental protection problems. Therefore, none of these three methods can be completely environmentally friendly. Summary of the invention

[0003] In view of the above-mentioned deficiencies in the prior art, the present invention provides an environmentally friendly industrial carbon capture process using plant fusion enzymes to solve the problem that the above-mentioned existing carbon dioxide capture process cannot be completely environmentally friendly.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0005] An industrial carbon capture and environmental protection process using plant fusion enzymes, characterized in that it comprises the following steps:

[0006] S1. Using ferroferric oxide as a carrier and relying on mesoporous material silica, carbonic anhydrase is immobilized by electrostatic interaction using a combination of covalent bonding and cross-linking methods, and immobilized heat-resistant and alkali-resistant carbonic anhydrase is prepared by fusing it with elastin-like polypeptides;

[0007] S2, fully fusing immobilized heat-resistant and alkali-resistant carbonic anhydrase with carboxylase to prepare plant fusion enzyme;

[0008] S3. Carbon dioxide is captured by plant fusion enzymes. Depending on the different gas component contents at the carbon dioxide capture point, plant fusion enzyme solutions of different concentrations are used, and different proportions of potassium carbonate are used.

[0009] The step S1 includes the following process flow:

[0010] A1. By adjusting the amino acids on the surface of carbonic anhydrase II molecule, Ala65, Phe93, Gln136, Lys153, Leu198, and Ala247 are mutated into Thr, Leu, His / Tyr, Asn, Met, and Thr, respectively, thereby mutating the enzyme into a heat-resistant and alkali-resistant carbonic anhydrase;

[0011] A2, with magnetic nanoparticles Fe3O4 as the core, the mesoporous material KIT-6 was coated on its surface to obtain a nanocomposite material Fe3O4@KIT-6 with a core-shell structure, Candida plicata lipase was fixed on its surface by covalent crosslinking with glutaraldehyde, and a one-dimensional nanochain with magnetic Fe3O4 nanoparticles growing and coating on its interface was synthesized by magnetic field guidance;

[0012] A3. In the presence of n-hexane, the interface co-assembly of hexadecyltrimethylammonium bromide and tetraethyl orthosilicate was further coated with a layer of mesoporous silica with adjustable pore size, and finally a magnetic mesoporous silica nanochain Fe3O4@nSiO2@mSiO2 with a double-shell structure was obtained;

[0013] A4, 2g SiO2 was dispersed in 18mL pH8.5, 0.05mol / L Tris-HCl buffer and ultrasonicated for 10 minutes, 40mg deoxynucleoside and 2mL 20mg / mL PEI aqueous solution were added while stirring, and the reaction was stirred at 28°C for 12 hours, and the obtained dark brown suspension was centrifuged at 12000r / min for 10 minutes, and the brown precipitate obtained by centrifugation was washed 3 times with deionized water and then dried to obtain PEI-SiO2 modification;

[0014] A5. The heat-resistant and alkali-resistant carbonic anhydrase and the elastin-like polypeptide were fused, and the target enzyme was purified by centrifugation using the ELPs self-separation technology. The silica-like particles were formed by the unique biomimetic silicification ability of ELPs. 0.1g of the PEI-SiO2 modified body was weighed and dispersed in 0.8mL of Tris-HCl buffer. After ultrasonic dispersion for 5 minutes, 0.2mL of 1mg / mL CA fusion solution and 10μL of 20wt% gallium aqueous solution were added in sequence to a final concentration of 0.1wt%. After thorough mixing, the mixture was placed in a desktop constant temperature oscillator at a speed of 140r / min and a temperature of 25°C. The immobilization time was 20 hours. The immobilized CA was washed 3 times with Tris-HCl buffer to finally obtain PEI-SiO2 immobilization. Finally, CA was adsorbed and immobilized by electrostatic interaction.

[0015] The step S2 includes the following process flow:

[0016] B1. Disperse 3 g of carboxylase extracted from corn plants in a buffer solution, disperse by ultrasonic for 10 min, and then add 0.01 g of immobilized heat-resistant and alkali-resistant carbonic anhydrase and mix thoroughly;

[0017] B2. Place in a desktop constant temperature oscillator at a speed of 1000 r / min, a temperature of 25°C, and a time of 20 hours, then wash with buffer 3 times to finally obtain the plant fusion enzyme.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. The carbon dioxide capture rate of the present invention can reach (0.81-0.92kgCO2m-3h-1), which is higher than that of alkaline solution (0.18-0.45kgCO2m-3h-1) and is not much different from that of amine solution (0.75-1.08kgCO2m-3h-1), but does not require the use of high pressure, high energy consumption, or the presence of highly toxic substances that pollute the environment, thereby achieving completely environmentally friendly capture of carbon dioxide;

[0020] 2. When the enzyme concentration of the immobilized carbonic anhydrase formed by the present invention reaches 9 mg / mL, the enzyme protein encapsulation rate reaches 91%. After being placed at 4°C for 72 hours, the leaked enzyme protein is only 0.96%. The optimum temperature of the immobilized carbonic anhydrase can reach 80°C, and the optimum alkalinity can reach pH 8.5. After 10 cycles, the relative activity is still 84.8%. When other immobilization methods are used, the enzyme protein encapsulation rate reaches up to 80%. The optimum temperature of the immobilized carbonic anhydrase does not exceed 65°C, and the optimum alkalinity is within pH 8.0. After 10 cycles, the relative activity does not exceed 54.85%. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the present invention, the technical solution of the present invention is further described below in conjunction with embodiments.

[0022] Example:

[0023] The specific steps and process of an industrial carbon capture environmental protection process using plant fusion enzymes of the present invention are as follows:

[0024] 1. Using ferrosoferric oxide as a carrier and relying on the mesoporous material silica, carbonic anhydrase (CA) was immobilized through electrostatic interaction by combining covalent bonding and cross-linking methods, and immobilized heat-resistant and alkali-resistant carbonic anhydrase was prepared by fusing it with elastin-like polypeptide.

[0025] 1. Prepare heat-resistant and alkali-resistant carbonic anhydrase using mutation technology.

[0026] We adjusted the amino acids on the surface of carbonic anhydrase II (hCA II) molecules, and mutated Ala65, Phe93, Gln136, Lys153, Leu198, and Ala247 to Thr, Leu, His / Tyr, Asn, Met, and Thr, respectively, thereby mutating the enzyme into a heat-resistant and alkali-resistant carbonic anhydrase. This heat-resistant carbonic anhydrase can maintain its activity stably at 90°C for 24 hours. When this heat-resistant and alkali-resistant carbonic anhydrase is added to the pre-separation high-temperature flue gas of the scrubber, its CO2 absorption rate is 40 times that of previous technologies.

[0027] 2. The modified heat-resistant and alkali-resistant carbonic anhydrase was prepared by using the magnetic mesoporous material with a double-shell structure, and then fused with elastin-like polypeptide to finally prepare the immobilized heat-resistant and alkali-resistant carbonic anhydrase.

[0028] (1) With magnetic nanoparticles Fe3O4 as the core, the mesoporous material KIT-6 was coated on its surface to obtain a nanocomposite Fe3O4@KIT-6 with a core-shell structure. The Candida plicata lipase was fixed on its surface by covalent crosslinking with glutaraldehyde. This core-shell structure composite carrier can effectively overcome the strong magnetic dipole-dipole interaction between magnetic nanoparticles. Through magnetic field guidance, a one-dimensional nanochain with magnetic Fe3O4 nanoparticles growing and coating on its interface was synthesized;

[0029] (2) In the presence of n-hexane, the interface of hexadecyltrimethylammonium bromide and tetraethyl orthosilicate was co-assembled, and a layer of mesoporous silica with adjustable pore size was further coated to finally obtain a magnetic mesoporous silica nanochain Fe3O4@nSiO2@mSiO2 with a double-shell structure;

[0030] (3) Disperse 2g SiO2 in 18mL pH8.5, 0.05mol / L Tris-HCl buffer and sonicate for 10 minutes, then add 40mg deoxynucleoside and 2mL 20mg / mL PEI aqueous solution while stirring, and stir at 28°C for 12 hours. Centrifuge the resulting dark brown suspension at 12000r / min for 10 minutes, wash the brown precipitate obtained by centrifugation with deionized water three times and dry it to obtain PEI-SiO2 modification;

[0031] (4) This heat-resistant and alkali-resistant carbonic anhydrase is fused with elastin-like polypeptides (ELPs), and the target enzyme is purified by centrifugation using the ELPs self-separation technology, and silica-like particles are formed through the unique biomimetic silicification ability of ELPs; 0.1g of the PEI-SiO2 modified body is weighed and dispersed in 0.8mL of Tris-HCl buffer (pH8.5, 0.05mol / L), and after ultrasonic dispersion for 5 minutes, 0.2mL of 1mg / mL CA fusion solution and 10μL of 20wt% gallium aqueous solution (final concentration of 0.1wt%) are added in sequence, and after being fully mixed, it is placed in a desktop constant temperature oscillator at a speed of 140r / min, a temperature of 25°C, and an immobilization time of 20 hours. The immobilized CA obtained is washed three times with Tris-HCl buffer to finally obtain PEI-SiO2 immobilization, and finally CA is adsorbed and immobilized by electrostatic interaction.

[0032] 2. Immobilized carbonic anhydrase and carboxylase were used to prepare a unique plant fusion enzyme.

[0033] 3 g of PEP carboxylase (absorbing carbon dioxide) extracted from corn plants was dispersed in a buffer solution, and after ultrasonic dispersion for 10 minutes, 0.01 g of the above-mentioned CA was added. After being fully mixed, it was placed in a desktop constant temperature oscillator at a speed of 1000 r / min, a temperature of 25°C, and a time of 20 hours. It was then washed three times with a buffer solution to finally obtain a unique plant fusion enzyme.

[0034] 3. A completely environmentally friendly innovative process for industrial carbon capture using the unique plant fusion enzyme mentioned above.

[0035] Depending on the different gas component content at the carbon dioxide capture point, different concentrations of plant fusion enzyme solutions are used, and different proportions of potassium carbonate (or calcium carbonate) are used. In industrial applications, carbon dioxide can be captured at room temperature and pressure. The number of equipment is small, the system structure is simple, and the operation and maintenance are simple. There is no need for high pressure, high energy consumption, and no risk of toxicity. Therefore, it is completely environmentally friendly. Using our innovative process equipment and processes, carbon dioxide can be captured in a completely environmentally friendly, low-cost, simple, safe and reliable manner.

[0036] The above are only embodiments of the present invention. The common knowledge such as the known specific structures and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field are aware of all the common technical knowledge in the technical field of the invention before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement the scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for the ordinary technicians in the relevant field to implement this application. It should be pointed out that for the technicians in this field, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. An environmentally friendly industrial carbon capture process using plant fusion enzymes, characterized in that: The steps include: S1. Using ferroferric oxide as a carrier and relying on mesoporous material silica, carbonic anhydrase is immobilized by electrostatic interaction using a combination of covalent bonding and cross-linking methods, and immobilized heat-resistant and alkali-resistant carbonic anhydrase is prepared by fusing it with elastin-like polypeptides; S2, fully fusing immobilized heat-resistant and alkali-resistant carbonic anhydrase with carboxylase to prepare plant fusion enzyme; S3. Carbon dioxide is captured by plant fusion enzymes. Depending on the different gas component contents at the carbon dioxide capture point, plant fusion enzyme solutions of different concentrations are used, and different proportions of potassium carbonate are used.

2. An environmentally friendly industrial carbon capture process using plant fusion enzymes as claimed in claim 1, characterized in that: The step S1 includes the following process flow: A1. By adjusting the amino acids on the surface of carbonic anhydrase II molecule, Ala65, Phe93, Gln136, Lys153, Leu198, and Ala247 are mutated into Thr, Leu, His / Tyr, Asn, Met, and Thr, respectively, thereby mutating the enzyme into a heat-resistant and alkali-resistant carbonic anhydrase; A2, with magnetic nanoparticles Fe3O4 as the core, the mesoporous material KIT-6 was coated on its surface to obtain a nanocomposite material Fe3O4@KIT-6 with a core-shell structure, Candida plicata lipase was fixed on its surface by covalent crosslinking with glutaraldehyde, and a one-dimensional nanochain with magnetic Fe3O4 nanoparticles growing and coating on its interface was synthesized by magnetic field guidance; A3. In the presence of n-hexane, the interface co-assembly of hexadecyltrimethylammonium bromide and tetraethyl orthosilicate was further coated with a layer of mesoporous silica with adjustable pore size, and finally a magnetic mesoporous silica nanochain Fe3O4@nSiO2@mSiO2 with a double-shell structure was obtained; A4, 2g SiO2 was dispersed in 18mL pH8.5, 0.05mol / L Tris-HCl buffer and ultrasonicated for 10 minutes, 40mg deoxynucleoside and 2mL 20mg / mL PEI aqueous solution were added while stirring, and the reaction was stirred at 28°C for 12 hours, and the obtained dark brown suspension was centrifuged at 12000r / min for 10 minutes, and the brown precipitate obtained by centrifugation was washed 3 times with deionized water and then dried to obtain PEI-SiO2 modification; A5. The heat-resistant and alkali-resistant carbonic anhydrase and the elastin-like polypeptide were fused, and the target enzyme was purified by centrifugation using the ELPs self-separation technology. The silica-like particles were formed by the unique biomimetic silicification ability of ELPs. 0.1g of the PEI-SiO2 modified body was weighed and dispersed in 0.8mL of Tris-HCl buffer. After ultrasonic dispersion for 5 minutes, 0.2mL of 1mg / mL CA fusion solution and 10μL of 20wt% gallium aqueous solution were added in sequence to a final concentration of 0.1wt%. After thorough mixing, the mixture was placed in a desktop constant temperature oscillator at a speed of 140r / min and a temperature of 25°C. The immobilization time was 20 hours. The immobilized CA was washed 3 times with Tris-HCl buffer to finally obtain PEI-SiO2 immobilization. Finally, CA was adsorbed and immobilized by electrostatic interaction.

3. The environmentally friendly industrial carbon capture process using plant fusion enzymes as claimed in claim 1, characterized in that: The step S2 includes the following process flow: B1. Disperse 3 g of carboxylase extracted from corn plants in a buffer solution, disperse by ultrasonic for 10 min, and then add 0.01 g of immobilized heat-resistant and alkali-resistant carbonic anhydrase and mix thoroughly; B2. Place in a desktop constant temperature oscillator at a speed of 1000 r / min, a temperature of 25°C, and a time of 20 hours, then wash with buffer three times to finally obtain the plant fusion enzyme.