Three-dimensional printing rapid forming device and method for carbon absorption material with core-shell structure

Abstract

The invention discloses a three-dimensional printing rapid forming device and method for a shell-core structure carbon absorption material. The device comprises a coaxial flow micro-scale channel, three injection pumps, an ultraviolet lamp, a three-axis numerical control printing platform and a computer. A movable printing head, a numerical control plate and a receiving container are arranged on the three-axis numerical control printing platform; a microsyringe is arranged on the injection pump; the coaxial flow micro-scale channel is fixed to a movable printing head of the three-axis numerical control printing platform, is vertically downward and moves in a user-defined mode through a numerical control plate connected with a computer. The receiving container is positioned below the coaxial flow micro-scale channel; and the ultraviolet lamps are arranged on two sides of the receiving container. The MECS formed by the method is accurate and adjustable in shell thickness, stable in chemical property and free of leakage, only gas exchange exists between the MECS and the outside, the high-speed carbon dioxide absorption function can be achieved, meanwhile, the configuration of a high-degree-of-freedom shell-core structure can be achieved through the three-dimensional printing technology, and the carbon absorption requirements in different scenes are met.

Description

Technical Field

[0001] The invention belongs to the technical field of carbon absorption materials, and in particular relates to a three-dimensional printing rapid prototyping device and method for a core-shell structure carbon absorption material. Background Art

[0002] In recent years, many new methods have emerged in carbon capture technology, such as amine-functionalized mesoporous solid adsorbents, amine-attached metal organic frameworks, membranes and high surface area droplets, and microcapsules have become an important tool for carbon capture. In particular, in recent years, the droplet microfluidics method can accurately generate and manipulate droplets in microchannels, providing a promising method to produce high-quality carbon capture microcapsules (Microencapsulated Carbon Sorbents, MECS). MECS is a small, flexible and efficient carbon dioxide capture material that can usually adapt to small spaces and provide high carbon dioxide capture efficiency. Traditional liquid absorbents have the disadvantages of easy corrosion of equipment, high regeneration energy consumption, and slow absorption rate during use. In order to solve these serious shortcomings of liquid absorbents, some researchers have proposed to use microcapsule encapsulation absorbents to solve these problems, that is, the liquid absorbent is wrapped in a high-permeability solid shell material, and the absorption and desorption function of carbon dioxide is realized while ensuring no leakage and only gas exchange with the outside world. This method overcomes the leakage and corrosion problems in the use of liquid absorbents in the past, and greatly reduces the cost of carbon dioxide capture.

[0003] Most of the MECS in existing research use carbonates or ionic liquids as core solvents, and there is almost no research on encapsulated composite core solvents. This is because the liquid phase mass transfer resistance of amine solutions is much smaller than that of carbonates and ionic liquids. When they are encapsulated as MECS, their mass transfer process will change from a liquid phase controlled process to a shell controlled process, which places higher requirements on the size of MECS. In special environments, space is limited, and it is crucial to maximize the number and effect of absorption capsules within a limited volume. Reasonable arrangement can not only ensure the maximum utilization of the absorbent, but also avoid the capsules from being too densely stacked, thereby affecting the permeability of the airflow. For example, in equipment or containers with complex shapes, optimizing the arrangement of capsules can better adapt to the spatial form, thereby achieving more efficient carbon dioxide capture. Therefore, the arrangement and molding of MECS is of great significance for improving carbon capture efficiency in special environments, such as narrow and special shapes.

[0004] The patent with the publication number CN113079346A and the invention name of a carbon capture material prepared by needle microfluidics and its preparation method uses potassium carbonate aqueous solution as adsorbent and TEGO RAD 2650 as shell material, and is prepared into carbon capture particles by microfluidic technology. The particles of this structure have a higher carbon dioxide absorption rate than pure liquid, but the initial absorption rate that can be improved by encapsulating a single absorbent is limited compared to the same volume of compound solvent. The patent with the publication number CN117920138A and the invention name of a method for preparing carbon adsorption microcapsules uses a microfluidic device with a coaxial needle assembly to prepare carbon adsorption capsules, so that the adsorbent solution forms microdroplets wrapped by liquid capsule shell materials under the flow shear action of the liquid capsule shell material, and finally solidifies it through a light irradiation device, but the two-phase microfluidic device used is difficult to accurately control the size of the generated droplets. In special environments, modular design and flexible arrangement are extremely important. The modular absorption structure can be adjusted and optimized according to specific environmental requirements, and flexibly adapt to spaces of different shapes, sizes or special requirements.

[0005] Therefore, it is extremely important to develop composite absorbents with better absorption performance and microscale channels that can precisely control the core-shell carbon absorption structure. Summary of the invention

[0006] The technical problem to be solved by the present invention is to address the deficiencies of the above-mentioned prior art and to provide a three-dimensional printing rapid prototyping device and method for a core-shell structured carbon absorption material, which combines fluid mechanics and carbon capture in the microscale, and constructs suitable absorption structures for different scenarios (such as narrow and irregular spaces) through three-dimensional printing methods. For example, three-dimensional printing can produce multi-level network structures, evenly distributed pores, and adsorption materials with specific surface properties. These designs can maximize the contact time and area between carbon dioxide and the material surface, thereby improving the adsorption efficiency and achieving a high-rate carbon dioxide absorption function. It can ensure that the chemical properties are stable and leak-free, and only gas exchange exists with the outside world. At the same time, the customization of the three-dimensional morphology is satisfied, so that the material can contact with carbon dioxide in an efficient manner, providing more adsorption surface area, and can design a carbon absorption structure with a complex pore structure to improve the adsorption efficiency of carbon dioxide.

[0007] In order to achieve the above technical objectives, the technical solution adopted by the present invention is:

[0008] A three-dimensional printing rapid prototyping device for core-shell structure carbon absorption materials, comprising a coaxial flow micro-scale channel, three injection pumps, an ultraviolet lamp, a three-axis CNC printing platform, and a computer;

[0009] The three-axis CNC printing platform is provided with a movable printing head, a CNC board and a receiving container;

[0010] The injection pump is provided with a micro-injector;

[0011] The coaxial flow microscale channel is fixed on the mobile print head of the three-axis CNC printing platform and moves vertically downward, and is customized by a CNC board connected to a computer;

[0012] The receiving container is located below the coaxial flow micro-scale channel;

[0013] The ultraviolet lamps are arranged on both sides of the receiving container.

[0014] To optimize the above technical solutions, the specific measures taken also include:

[0015] The above-mentioned coaxial flow microscale channel includes an inner phase microfluidic channel, an intermediate phase microfluidic channel and an outer phase microfluidic channel; the intermediate phase microfluidic channel is a main channel for the circulation of shell materials, the inner phase microfluidic channel is used for the circulation of core solvents, and the outer phase microfluidic channel is used for the circulation of outer phase solutions, wherein the outer phase solution is a glycerol solution doped with a surfactant;

[0016] The inner phase microfluidic channel, the intermediate phase microfluidic channel and the outer phase microfluidic channel are respectively connected to a microinjector on a syringe pump, and the corresponding microinjector is used to slowly inject the core solvent, shell material and outer phase solution into the inner phase microfluidic channel, the intermediate phase microfluidic channel and the outer phase microfluidic channel.

[0017] The above-mentioned inner phase microfluidic channel and intermediate phase microfluidic channel are T-shaped structures. As the inner phase fluid continues to flow in, its front end gradually deforms under the shear force and pressure of the intermediate phase. When the pressure accumulates to a level sufficient to overcome the surface tension and viscous resistance of the inner phase, the inner phase is sheared to form droplets; the intermediate phase microfluidic channel and the inner phase microfluidic channel are located in the tube of the outer phase channel as a coaxial structure and are shorter than the discharge port.

[0018] The above-mentioned coaxial flow micro-scale channel includes a stainless steel point needle, a T-shaped three-way pipe plastic joint, a glass capillary, a glass square tube, a flat-head needle and a glass sheet;

[0019] The stainless steel spot needle and the glass capillary are connected to the two ends of the T-shaped three-way plastic joint to form a T-shaped structure for generating core droplets;

[0020] The glass square tube is an external phase microfluidic channel, which is used for the circulation of external phase solution and is coaxial with a stainless steel needle and a glass capillary. The stainless steel needle is an intermediate phase microfluidic channel. The glass square tube, the stainless steel needle, a T-shaped three-way pipe plastic joint and a glass capillary are arranged on a glass sheet. The T-shaped three-way pipe plastic joint is an internal phase microfluidic channel. A flat-head needle is arranged at the connection between the glass square tube and the glass capillary and is perpendicular to the glass sheet, which is used to generate core-shell droplets in which a core solvent is coated by a shell material.

[0021] The inner diameter of the glass capillary is larger than the outer diameter of the stainless steel needle; the inner diameter of the glass square tube is 1.1 mm and larger than the outer diameter of the glass capillary by 0.1 mm;

[0022] The glass capillary extends to one side of the position of the flat-head needle and is 3-4 mm away from the exit of the glass square tube;

[0023] The above-mentioned stainless steel point needle, T-shaped three-way pipe plastic joint, glass capillary, glass square tube, flat-head needle and glass sheet are sealed with epoxy resin.

[0024] The glass capillary and stainless steel needle were treated with hydrophobicity by soaking in oil film cleaner for 8 hours, and the glass square tube was treated with oleophobicity by soaking in 5wt% PVA for 1 hour to prevent the coaxial flow micro-scale channel from being blocked during the flow process.

[0025] A three-dimensional printing rapid prototyping method for a core-shell structure carbon absorption material, the method comprising:

[0026] (1) dissolving sodium carbonate in distilled water, adding amine as an additive, and adding phenolphthalein dye, and mixing them into a binary system by ultrasonic oscillation at an oscillation frequency of 40 kHz and a temperature of 293.15 K for 20 min to obtain a core solvent;

[0027] (2) adding 1 wt% to 5 wt% of nano-magnetic particles to a photocurable resin TEGO Rad 2650 having a high air permeability, stirring the mixture at a speed of 1000 r / min and a temperature of 293.15 K for 10 min in a dark environment to obtain a shell material;

[0028] (3) dissolving glycerol in distilled water and adding surfactant polyvinyl alcohol, stirring at a speed of 600 r / min and a temperature of 343.15 K for 15 min to obtain an external phase solution;

[0029] (4) placing the core solvent, shell material, and external phase solution into a syringe pump respectively, and connecting the corresponding microinjectors to the inner phase microfluidic channel, the intermediate phase microfluidic channel, and the external phase microfluidic channel of the coaxial flow microscale channel respectively;

[0030] (5) The coaxial flow microscale channel is fixed on the mobile print head through a three-dimensional numerical control printing platform, and the movement of the mobile print head on the XYZ axis of the three-dimensional numerical control printing platform is controlled by a numerical control board connected to a computer. The coaxial flow microscale channel controls the flow of materials, and the corresponding micro-injector is controlled by adjusting the parameters of the injection pump to slowly inject the core solvent, shell material and external phase solution into the inner phase microfluidic channel, the intermediate phase microfluidic channel and the external phase microfluidic channel, and the amount of material in each layer is adjusted by the injection pump. At the same time, the three-dimensional numerical control printing platform is controlled by a computer to further control the position and generation rate of material generation, and the arrangement mode is adjusted to realize three-dimensional printing. First, the first The first-stage T-shaped structure generates core droplets through a stainless steel point needle as the intermediate phase inlet, a T-shaped three-way pipe plastic joint as the inner phase inlet and a glass capillary; the second-stage coaxial flow structure generates core-shell droplets composed of a shell material and a core solvent through a glass square tube, a glass sheet and a flat-headed needle as the outer phase inlet. After the droplets are stably generated, an ultraviolet lamp is used to irradiate symmetrically on both sides of the bottom of the receiving container to induce the surface of the droplets to polymerize to form separate core-shell microspheres, or to bond with the previously formed microspheres. Each time a layer of resin is irradiated, a solid layer is formed. The object is constructed by stacking layer by layer, and the core-shell structures are cross-linked and bonded to each other to prepare cross-linked core-shell structured carbon absorption materials of different shapes.

[0031] In the above (5), the injection speed of the injection pump is controlled so that the inner phase flow rate is 10-20 μL / min, the middle phase flow rate is 10-20 μL / min, and the outer phase flow rate is 400-800 μL / min. The moving speed of the coaxial flow microscale channel is adjusted between 0-1 mm / s using a three-axis CNC printing platform and a computer.

[0032] The present invention has the following beneficial effects:

[0033] (1) For the first time, sodium carbonate-amine (including but not limited to primary amine, secondary amine, tertiary amine) binary system absorbent was encapsulated by microfluidic technology. The introduction of amine significantly increased the reaction rate. This is because amine molecules have strong nucleophilicity and can react quickly with carbon dioxide to form intermediates. The amination reaction has faster kinetic characteristics than the simpler physical absorption process. This allows more carbon dioxide to be captured in a shorter time. After adding amines, the number of effective active sites in the solution increases, which can react with more carbon dioxide molecules. This greatly increases the amount of carbon dioxide that can be absorbed in the same volume of solution.

[0034] (2) After adding magnetic particles, the application of magnetic field can provide better control means for core-shell carbon absorption materials. For example, through the action of external magnetic field, the distribution of magnetic particles inside can be guided, or the arrangement of particles can be optimized and directional transport can be achieved during carbon capture, thereby improving its adsorption efficiency. In some application scenarios, it may be necessary to precisely position the carbon dioxide adsorbent in a specific area or equipment. The directional transport of magnetic particles can ensure the accurate position of the adsorbent, thereby improving the overall efficiency. When releasing carbon dioxide, the magnetic particles can be adjusted through the magnetic field to ensure the position and state of the adsorbent during the release process, thereby controlling the release rate and conditions of carbon dioxide.

[0035] (3) Use a three-dimensional printing device to print the microfluidic capsule layer by layer according to a predetermined printing path, and design the printing path of each layer according to the predetermined three-dimensional structure. The arrangement order of MECS in each layer is optimized according to the geometric characteristics and functional requirements of the object. According to the printing path, the desired structure is formed by stacking layer by layer. For the droplets containing photosensitive materials of the present invention, ultraviolet light irradiation is used for curing treatment to ensure the shape of the printed object is stable. The microscale channel can be fixed on the print head through a three-dimensional numerical control platform, and the movement of the nozzle on the XYZ axis of the printing platform can be controlled by a computer. At the same time, the flow of the material can be accurately controlled by a microfluidic device, and the amount of material in each layer can be adjusted by an injection pump. At the same time, the position and generation rate of the material generation can be further regulated by a computer-controlled movable lifting platform to ensure accurate printing effects. The liquid photosensitive resin is irradiated by laser, and a layer of resin is cured each time to form a solid layer. The object is constructed by stacking layer by layer, and the shell-core structure is cross-linked and bonded to each other, so that absorption structures of different shapes can be prepared. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of three-dimensional printing;

[0037] Figure 2 It is a schematic diagram of the structure of the coaxial flow micro-scale channel assembled by capillaries in the present invention;

[0038] Figure 3 This is the flow diagram inside the microfluidic device;

[0039] Figure 4 Microscopic images of carbon absorber materials with different shell thicknesses;

[0040] Figure 5 It is a cross-linked absorption structure in three-dimensional printing;

[0041] Figure 6 This is a graph of carbon dioxide absorption test;

[0042] In the accompanying drawings, the components represented by the reference numerals are as follows:

[0043] 1-coaxial flow microscale channel, 1.1-stainless steel dot needle, 1.2-T-type three-way pipe plastic connector, 1.3-glass capillary, 1.4-glass square tube, 1.5-flat head needle, 1.6-glass sheet, 2-mobile print head, 3-CNC board, 4-syringe pump, 5-microinjector, 6-ultraviolet lamp, 7-cross-linked absorption structure, 8-three-dimensional CNC printing platform, 9-computer. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0045] Although the steps in the present invention are arranged with numbers, they are not used to limit the order of the steps. Unless the order of the steps is clearly stated or the execution of a certain step requires other steps as a basis, the relative order of the steps can be adjusted. It is understood that the term "and / or" used in this article involves and covers any and all possible combinations of one or more of the associated listed items.

[0046] The present invention provides a three-dimensional printing rapid prototyping device for a core-shell structured carbon absorption material, wherein the core-shell structured carbon absorption material comprises a shell layer and a core solvent wrapped in the shell layer, the core solvent is a binary system absorbent composed of carbonate and amine solution (including but not limited to primary amine, secondary amine, tertiary amine), and the core-shell structured carbon absorption material is prepared by a two-stage coaxial flow microscale channel 1 assembled by a capillary. The coaxial flow microscale channel 1 involved has a simple structure and good controllability, can accurately control the shell thickness, and balance the absorption efficiency and structural strength.

[0047] Preferably, the core-shell carbon absorbent material of the present invention comprises Figure 1 The coaxial flow micro-scale channel 1 shown encapsulates the sodium carbonate-amine binary system absorber in a photo-curable resin with high air permeability.

[0048] The binary system core solvent is encapsulated by a photocurable resin material with high air permeability, and a carbon absorption shell core structure carbon absorption material is formed by photocuring; the photocurable resin with high air permeability is TEGO Rad 2650, and is doped with nano magnetic particles, which can achieve directional transportation under the action of a magnetic field.

[0049] Preferably, if Figure 1 As shown, the three-dimensional printing rapid prototyping device of the core-shell structure carbon absorption material includes a coaxial flow micro-scale channel 1, three injection pumps 4, an ultraviolet lamp 6, a three-axis CNC printing platform 8, and a computer 9;

[0050] The three-axis CNC printing platform 8 is provided with the mobile printing head 2, the CNC board 3 and the receiving container;

[0051] The injection pump 4 is provided with a micro-injector 5;

[0052] The coaxial flow microscale channel 1 is fixed on a moving print head 2 of a three-axis CNC printing platform 8 and moves vertically downward, and is moved by a CNC board 3 connected to a computer 9;

[0053] The receiving container is located below the coaxial flow micro-scale channel 1;

[0054] The ultraviolet lamps 6 are arranged on both sides of the receiving container.

[0055] The core-shell structure carbon absorption material can fix the coaxial flow micro-scale channel 1 on the mobile printing head 2 through the three-dimensional numerical control printing platform 8, and control the nozzle to move on the XYZ axis of the three-dimensional numerical control printing platform 8 through the computer 9 to ensure that accurate three-dimensional printing operations can be achieved. The microfluidic device can accurately control the flow of the material, and adjust the amount of material in each layer through the injection pump 4. At the same time, the movable lifting platform is controlled by the computer 9 to further regulate the position and generation rate of the material generation to ensure accurate printing effects, and the arrangement mode is adjusted to achieve three-dimensional printing. The liquid photosensitive resin is irradiated by laser, and a layer of resin is cured each time to form a solid layer. The object is constructed by stacking layer by layer, and the core-shell structures are cross-linked and bonded to each other to prepare absorption structures of different shapes.

[0056] Preferably, the coaxial flow microscale channel 1 includes an inner phase microfluidic channel, an intermediate phase microfluidic channel and an outer phase microfluidic channel; the intermediate phase microfluidic channel is a main channel for the circulation of shell materials, the inner phase microfluidic channel is used for the circulation of core solvents, and the outer phase microfluidic channel is a glass square tube 1.4, which is used for the circulation of outer phase solutions, specifically for the circulation of glycerol solutions doped with surfactants; the intermediate phase microfluidic channel and the inner phase microfluidic channel are T-shaped structures, and as the inner phase fluid continues to flow in, its front end gradually deforms under the shear force and pressure of the intermediate phase. When the pressure accumulates to a certain level, which is sufficient to overcome the surface tension and viscous resistance of the inner phase, the inner phase will be sheared to form droplets; the intermediate phase microfluidic channel and the inner phase microfluidic channel are located in the tube of the outer phase channel as a coaxial structure, and are shorter than the discharge port;

[0057] The coaxial flow microscale channel 1 involved in the present invention is mainly composed of a stainless steel point needle 1.1 (intermediate phase inlet, i.e., shell material), a glass capillary 1.3, a glass square tube 1.4, a T-shaped three-way pipe plastic joint 1.2 (internal phase inlet, i.e., core solvent), a flat-head needle 1.5 and a glass sheet 1.6, which are sealed with epoxy resin and fixed using a three-axis CNC printing platform 8, and customized movement is performed by adjusting parameters.

[0058] The coaxial flow microscale channel 1 is a two-stage device, the first stage is a T-shaped structure, which is composed of a stainless steel point needle 1.1 (i.e., the middle phase inlet), a T-shaped three-way pipe plastic joint 1.2 (i.e., the inner phase inlet) and a glass capillary 1.3, thereby generating core droplets; the second stage is composed of a glass square tube 1.4, a glass sheet 1.6 and a flat-head needle 1.5 (i.e., the outer phase inlet), which is a coaxial flow structure, thereby generating shell-core droplets in which the core solvent is covered by the shell material; Figure 2 The internal flow diagram is shown in Figure 3 As shown;

[0059] The inner diameter of the glass capillary 1.3 is larger than the outer diameter of the stainless steel needle 1.1; the inner diameter of the glass square tube 1.4 is 1.1 mm and is 0.1 mm larger than the outer diameter of the glass capillary 1.3;

[0060] The glass capillary 1.3 extends to the right side of the flat-head needle 1.5, 3-4 mm away from the outlet of the glass square tube 1.4; the stainless steel point needle 1.1, glass capillary 1.3 and glass square tube 1.4 are coaxially fixed by a T-shaped three-way plastic joint 1.2, a flat-head needle 1.5 and a glass sheet 1.6, and sealed with epoxy resin.

[0061] The glass capillary 1.3 and the stainless steel needle 1.1 are treated with hydrophobicity by soaking in oil film cleaner (SOFT99) for 8 hours, and the glass square tube 1.4 is treated with oleophobicity by soaking in 5wt% PVA for 1 hour to prevent the coaxial flow microscale channel 1 from being blocked during the flow process.

[0062] The present invention encapsulates the carbon dioxide absorbent solution through a photocurable resin material with high air permeability, and forms a core-shell structure carbon absorption material (Microencapsulated Carbon Sorbents, MECS) through photocuring. The shell thickness is precisely adjustable, the chemical properties are stable and there is no leakage. There is only gas exchange with the outside world, and the high-rate carbon dioxide absorption function can be achieved. At the same time, the three-dimensional printing technology can be used to realize the configuration of the core-shell structure with high freedom, meeting the carbon absorption needs in different scenarios.

[0063] The present invention also provides a three-dimensional printing rapid prototyping method for a core-shell structure carbon absorbent material, which realizes the preparation of the core-shell structure carbon absorbent material based on a coaxial flow microscale channel 1, comprising:

[0064] First, the coaxial flow microscale channel 1 is designed as follows:

[0065] The coaxial flow microscale channel 1 required for the experiment is prepared by the capillary assembly method. The first stage is a T-shaped structure, which is composed of a stainless steel point needle 1.1, a T-shaped three-way pipe plastic joint 1.2 and a glass capillary 1.3, thereby generating a core droplet; the second stage is composed of a glass square tube 1.4, a glass sheet 1.6 and a flat-head needle 1.5, which is a coaxial flow structure, thereby generating a shell-core droplet with a core solvent coated by a shell material. The entire device is bonded together with epoxy resin as an adhesive; and is fixed using a three-axis CNC printing platform 8, and customized movement is performed by adjusting parameters through a computer 9.

[0066] Further, by Figure 1 The coaxial flow microscale channel 1 shown encapsulates the sodium carbonate-amine binary system absorbent in a photocurable resin with high air permeability to obtain a core-shell structure carbon absorbent material. The MECS synthesis process is as follows:

[0067] (1) dissolving sodium carbonate in distilled water, adding amine (including but not limited to primary amine, secondary amine, tertiary amine) as an additive, and adding a small amount of phenolphthalein for dyeing, and mixing them into a binary system by ultrasonic oscillation (40 kHz, 293.15K, 20 min) to obtain a core solvent;

[0068] (2) adding 1 wt% to 5 wt% of nanomagnetic particles to TEGO Rad 2650, stirring at a speed of 1000 r / min and a temperature of 293.15 K for 10 min in a dark environment, and obtaining a shell material;

[0069] (3) dissolving glycerol in distilled water and adding surfactant PVA, stirring at a speed of 600 r / min and a temperature of 343.15 K for 15 min to obtain an external solution;

[0070] (4) placing the core solvent, shell material, and external phase solution into a syringe pump 4 respectively, and the corresponding microinjectors 5 are connected to the inner phase microfluidic channel, the intermediate phase microfluidic channel, and the external phase microfluidic channel of the coaxial flow microscale channel 1 respectively;

[0071] The MECS preparation device is mainly composed of a syringe pump 4, a micro-injector 5, a coaxial flow micro-scale channel, a polytetrafluoroethylene tube (PE tube), an iron stand, a receiving container and an ultraviolet lamp 7. In order to transport the core solvent, shell material and external liquid, a connector is installed at the end of the coaxial flow micro-scale channel 1, and a T-type three-way pipe plastic connector 1.2, a stainless steel point needle 1.1 connector and a flat-head needle 1.5 are respectively connected to the micro-injector 5 on the three syringe pumps 4 using a PE tube;

[0072] (5) The coaxial flow microscale channel 1 is fixed on the mobile print head 2 through the three-dimensional numerical control printing platform 8, and the mobile print head 2 is controlled to move on the XYZ axis of the three-dimensional numerical control printing platform 8 through the numerical control board 3 connected to the computer 9. The coaxial flow microscale channel 1 controls the flow of materials. By adjusting the parameters of the injection pump 4, the corresponding micro-injector 5 is controlled to slowly inject the core solvent, shell material and external phase solution into the inner phase microfluidic channel, the intermediate phase microfluidic channel and the external phase microfluidic channel, and the amount of material in each layer is adjusted by the injection pump 4. At the same time, the three-dimensional numerical control printing platform 8 is controlled by the computer 9 to further regulate the position and generation rate of material generation, and the arrangement mode is adjusted to realize three-dimensional printing. The coaxial flow microscale channel 1 is a two-stage device, and the first stage is a T-type structure. The structure is composed of a stainless steel point needle 1.1 (i.e., the intermediate phase inlet), a T-shaped three-way plastic joint 1.2 (i.e., the inner phase inlet) and a glass capillary 1.3, thereby generating a core droplet; and the second stage is composed of a glass square tube 1.4, a glass sheet 1.6 and a flat-headed needle 1.5 (i.e., the outer phase inlet), which is a coaxial flow structure, thereby generating a shell-core droplet in which a core solvent is coated with a shell material. After the droplets are stably generated, an ultraviolet lamp 6 is used to irradiate symmetrically on both sides of the bottom of the receiving container to induce the surface of the droplet to polymerize to form a separate core-shell microsphere, or to bond with the previously formed microsphere. Each time a layer of resin is irradiated, a solid layer is formed. The object is constructed by stacking layer by layer, and the core-shell structure is cross-linked and bonded to each other to prepare a cross-linked core-shell structure carbon absorption material of different shapes.

[0073] Preferably, the parameters of the injection pump 4 are adjusted to slowly inject the core solvent, shell material and external phase solution into the coaxial flow micro-scale channel, and the injection speed of the injection pump 4 is controlled to make the internal phase flow rate 10-20 μL / min, the intermediate phase flow rate 10-20 μL / min, and the external phase flow rate 400-800 μL / min, and the moving speed of the coaxial flow micro-scale channel 1 is adjusted between 0-1 mm / s by using the three-axis CNC printing platform 8 and the computer 9. After the droplets are stably generated, ultraviolet light (0-1 W / cm 2 ) Irradiate symmetrically on both sides of the bottom of the receiving solution to induce the surface of the droplet to polymerize to form separate core-shell microspheres, or to bond with previously formed microspheres. Finally, take a sample with a plastic dropper, wipe the surface dry, and you can get a cross-linked core-shell carbon absorber;

[0074] The MECS can adjust the thickness of the shell material by adjusting the flow rate of the injection pump 4, thereby adjusting its absorption rate;

[0075] In the specific implementation, the core solvent, i.e., the inner phase flow rate, is kept constant in step (5), and the shell material thickness is adjusted by adjusting the shell material flow rate, thereby changing the absorption rate of the MECS. Table 1 lists the specific flow ratio and shell-core size information. The prepared MECS is placed in an absorption device for absorption test to obtain its absorption curve.

[0076] Example 1

[0077] The sodium carbonate-amine (including but not limited to primary amine, secondary amine, tertiary amine) binary system absorbent is evenly mixed by ultrasonication, and a small amount of phenolphthalein is added for dyeing to obtain a core solvent, which is then introduced into the inner phase microfluidic channel of the coaxial flow microscale channel 1 through a microinjector 5 and a PE tube; the photocurable resin material and magnetic particles are evenly mixed to obtain a shell material, which is then introduced into the intermediate phase microfluidic channel of the coaxial flow microscale channel 1 through a microinjector 5 and a PE tube; glycerol is dissolved in distilled water and a surfactant PVA is added to obtain an external liquid, which is then introduced into the outer phase microfluidic channel of the coaxial flow microscale channel 1 through a microinjector 5 and a PE tube.

[0078] Adjust the parameters of the injection pump 4, slowly inject the core solvent, shell material and external phase solution into the coaxial flow microscale channel, control the injection speed of the injection pump 4 to make the inner phase flow rate 15μL / min, the middle phase flow rate 20μL / min, and the external phase flow rate 500μL / min, and use the three-axis CNC printing platform 8 and the computer 9 to adjust the moving speed of the coaxial flow microscale channel 1 between 0-1mm / s.

[0079] The coaxial flow microscale channel 1 is fixed on the mobile printing head 2 through the three-dimensional numerical control printing platform 8, and the nozzle is controlled by the computer 9 to move on the XYZ axis of the three-dimensional numerical control printing platform 8. The microfluidic capsule is printed layer by layer according to the predetermined printing path using the three-dimensional printing equipment. According to the predetermined three-dimensional structure, the printing path of each layer is designed. By adjusting the moving speed of the coaxial flow microscale channel 1, it is possible to print absorption structures of different specific shapes, and the arrangement order of MECS of each layer is optimized according to the geometric characteristics and functional requirements of the object. According to the printing path, the required structure is formed by stacking layer by layer.

[0080] Adjust the parameters of the syringe pump 4 to deliver the core solvent, shell material and external liquid respectively, and form droplets at the outlet of the glass square tube 1.4. After the droplets are stably generated, use ultraviolet light (0-1W / cm 2 ) is symmetrically irradiated on both sides of the bottom of the receiving solution to induce the surface polymerization of the droplets to form core-shell microspheres.

[0081] Finally, a plastic dropper is used to take samples, and after wiping the surface dry, the granular core-shell structured carbon absorption material MECS1 is obtained.

[0082] For the droplets containing photosensitive materials of the present invention, ultraviolet rays are used to irradiate the liquid photosensitive resin, and each irradiation solidifies a layer of resin to form a solid layer, which is stacked layer by layer to construct an object, and the shell-core structure is cross-linked and bonded to each other to prepare absorption junctions of different shapes, ensuring that the shape of the printed object is stable. The printing process and the cross-linked absorption structure during printing are shown in FIG. Figure 5 .

[0083] Example 2

[0084] The sodium carbonate-amine (including but not limited to primary amine, secondary amine, tertiary amine) binary system absorbent is evenly mixed by ultrasonication, and a small amount of phenolphthalein is added for dyeing to obtain a core solvent, which is then introduced into the inner phase microfluidic channel of the coaxial flow microscale channel 1 through a microinjector 5 and a PE tube; the photocurable resin material and magnetic particles are evenly mixed to obtain a shell material, which is then introduced into the intermediate phase microfluidic channel of the coaxial flow microscale channel 1 through a microinjector 5 and a PE tube; glycerol is dissolved in distilled water and a surfactant PVA is added to obtain an external liquid, which is then introduced into the outer phase microfluidic channel of the coaxial flow microscale channel 1 through a microinjector 5 and a PE tube.

[0085] Adjust the parameters of the injection pump 4, slowly inject the core solvent, shell material and external phase solution into the coaxial flow microscale channel, control the injection speed of the injection pump 4 to make the inner phase flow rate 15μL / min, the middle phase flow rate 10μL / min, and the external phase flow rate 400μL / min, and use the three-axis CNC printing platform 8 and the computer 9 to adjust the moving speed of the coaxial flow microscale channel 1 between 0-1mm / s.

[0086] The coaxial flow microscale channel 1 is fixed on the mobile printing head 2 through the three-dimensional numerical control printing platform 8, and the nozzle is controlled by the computer 9 to move on the XYZ axis of the three-dimensional numerical control printing platform 8. The microfluidic capsule is printed layer by layer according to the predetermined printing path using the three-dimensional printing equipment. According to the predetermined three-dimensional structure, the printing path of each layer is designed. By adjusting the moving speed of the coaxial flow microscale channel 1, it is possible to print absorption structures of different specific shapes, and the arrangement order of MECS of each layer is optimized according to the geometric characteristics and functional requirements of the object. According to the printing path, the required structure is formed by stacking layer by layer.

[0087] Adjust the parameters of the syringe pump 4 to deliver the core solvent, shell material and external liquid respectively, and form droplets at the outlet of the glass square tube 1.4. After the droplets are stably generated, use ultraviolet light (0-1W / cm 2 ) is symmetrically irradiated on both sides of the bottom of the receiving solution to induce the surface polymerization of the droplets to form core-shell microspheres.

[0088] Finally, a plastic dropper is used to take samples, and after wiping the surface dry, the granular core-shell structured carbon absorption material MECS2 is obtained.

[0089] For the droplets containing photosensitive materials of the present invention, the liquid photosensitive resin is irradiated by ultraviolet rays, and a layer of resin is cured each time to form a solid layer. The object is constructed layer by layer, and the shell-core structures are cross-linked and bonded to each other to prepare absorption junctions of different shapes, thereby ensuring the shape stability of the printed object.

[0090] Example 3

[0091] The sodium carbonate-amine (including but not limited to primary amine, secondary amine, tertiary amine) binary system absorbent is evenly mixed by ultrasonication, and a small amount of phenolphthalein is added for dyeing to obtain a core solvent, which is then introduced into the inner phase microfluidic channel of the coaxial flow microscale channel 1 through a microinjector 5 and a PE tube; the photocurable resin material and magnetic particles are evenly mixed to obtain a shell material, which is then introduced into the intermediate phase microfluidic channel of the coaxial flow microscale channel 1 through a microinjector 5 and a PE tube; glycerol is dissolved in distilled water and a surfactant PVA is added to obtain an external liquid, which is then introduced into the outer phase microfluidic channel of the coaxial flow microscale channel 1 through a microinjector 5 and a PE tube.

[0092] Adjust the parameters of the injection pump 4, slowly inject the core solvent, shell material and external phase solution into the coaxial flow microscale channel, control the injection speed of the injection pump 4 to make the inner phase flow rate 15μL / min, the middle phase flow rate 8μL / min, and the external phase flow rate 350μL / min, and use the three-axis CNC printing platform 8 and the computer 9 to adjust the moving speed of the coaxial flow microscale channel 1 between 0-1mm / s.

[0093] The coaxial flow microscale channel 1 is fixed on the mobile printing head 2 through the three-dimensional numerical control printing platform 8, and the nozzle is controlled by the computer 9 to move on the XYZ axis of the three-dimensional numerical control printing platform 8. The microfluidic capsule is printed layer by layer according to the predetermined printing path using the three-dimensional printing equipment. According to the predetermined three-dimensional structure, the printing path of each layer is designed. By adjusting the moving speed of the coaxial flow microscale channel 1, it is possible to print absorption structures of different specific shapes, and the arrangement order of MECS of each layer is optimized according to the geometric characteristics and functional requirements of the object. According to the printing path, the required structure is formed by stacking layer by layer.

[0094] Adjust the parameters of the syringe pump 4 to deliver the core solvent, shell material and external liquid respectively, and form droplets at the outlet of the glass square tube 1.4. After the droplets are stably generated, use ultraviolet light (0-1W / cm 2 ) is symmetrically irradiated on both sides of the bottom of the receiving solution to induce the surface polymerization of the droplets to form core-shell microspheres.

[0095] Finally, a plastic dropper is used to take samples, and after wiping the surface dry, the granular core-shell structured carbon absorption material MECS3 is obtained.

[0096] For the droplets containing photosensitive materials of the present invention, the liquid photosensitive resin is irradiated by ultraviolet rays, and a layer of resin is cured each time to form a solid layer. The object is constructed layer by layer, and the shell-core structures are cross-linked and bonded to each other to prepare absorption junctions of different shapes, thereby ensuring the shape stability of the printed object.

[0097] The specific preparation parameters of the MECS of the above Examples 1-3 are as follows:

[0098] Table 1 Preparation parameters of MECS

[0099]

[0100] The morphology and particle size distribution of the prepared MECS are as follows: Figure 4 As shown in Table 1 and Figure 4 It can be seen that MECS presents a regular spherical shape with a smooth surface, uniform distribution of core solvent, and the thickness of the shell material gradually increases with the increase of shell material flow rate.

[0101] The sodium carbonate-amine binary system MECS was placed in the absorption device for absorption test. During the entire absorption test, the MECS with three different shell thicknesses showed different absorption performances. The specific absorption performance curve is shown in Figure 6 . Within the initial 7 minutes, the initial absorption rate of MECS3 is higher than that of MECS1 and higher than that of MECS2. Within 7 to 10 minutes, MECS3>MECS2>MECS1. The overall absorption rate is not greatly improved, but it is higher than that of pure core solvent. This is because carbon dioxide molecules move from high concentration areas to low concentration areas, a process called diffusion. When carbon dioxide contacts the outer shell of the capsule, it needs to pass through the shell to enter the capsule. The thicker the shell, the farther the carbon dioxide diffuses, which significantly increases the diffusion time and further affects the absorption rate. After the absorption stabilizes, the overall absorption amount is in the order of MECS3>MECS2>MECS1.

[0102] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0103] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A three-dimensional printing rapid prototyping device for core-shell structure carbon absorption materials, characterized in that: It includes a coaxial flow microscale channel, three syringe pumps, UV lamp, three-axis CNC printing platform, and computer; The three-axis CNC printing platform is provided with a movable printing head, a CNC board and a receiving container; The injection pump is provided with a micro-injector; The coaxial flow microscale channel is fixed on the mobile print head of the three-axis CNC printing platform and moves vertically downward, and is customized by a CNC board connected to a computer; The receiving container is located below the coaxial flow micro-scale channel; The ultraviolet lamps are arranged on both sides of the receiving container.

2. A three-dimensional printing rapid prototyping device for a core-shell carbon absorbent material according to claim 1, characterized in that: The coaxial flow microscale channel includes an inner phase microfluidic channel, an intermediate phase microfluidic channel and an outer phase microfluidic channel; The middle phase microfluidic channel is the main channel for the circulation of shell materials, the inner phase microfluidic channel is for the circulation of core solvents, and the outer phase microfluidic channel is for the circulation of outer phase solutions, wherein the outer phase solution is a glycerol solution doped with a surfactant; The inner phase microfluidic channel, the intermediate phase microfluidic channel and the outer phase microfluidic channel are respectively connected to a microinjector on a syringe pump, and the corresponding microinjector is used to slowly inject the core solvent, shell material and outer phase solution into the inner phase microfluidic channel, the intermediate phase microfluidic channel and the outer phase microfluidic channel.

3. A three-dimensional printing rapid prototyping device for core-shell carbon absorbent material according to claim 2, characterized in that: The inner phase microfluidic channel and the intermediate phase microfluidic channel are of T-shaped structure. As the inner phase fluid continuously flows in, the front end thereof gradually deforms under the shear force and pressure of the intermediate phase. When the pressure accumulates to a level sufficient to overcome the surface tension and viscous resistance of the inner phase, the inner phase is sheared to form droplets. The intermediate phase microfluidic channel and the inner phase microfluidic channel are coaxially located in the tube of the outer phase channel and are shorter than the discharge port.

4. A three-dimensional printing rapid prototyping device for a core-shell structure carbon absorbent material according to claim 2 or 3, characterized in that: The coaxial flow microscale channel includes a stainless steel point needle, a T-shaped three-way pipe plastic joint, a glass capillary, a glass square tube, a flat-head needle and a glass sheet; The stainless steel spot needle and the glass capillary are connected to the two ends of the T-shaped three-way plastic joint to form a T-shaped structure for generating core droplets; The glass square tube is an external phase microfluidic channel, which is used for the circulation of external phase solution and is coaxial with a stainless steel needle and a glass capillary. The stainless steel needle is an intermediate phase microfluidic channel. The glass square tube, the stainless steel needle, a T-shaped three-way pipe plastic joint and a glass capillary are arranged on a glass sheet. The T-shaped three-way pipe plastic joint is an internal phase microfluidic channel. A flat-head needle is arranged at the connection between the glass square tube and the glass capillary and is perpendicular to the glass sheet, which is used to generate core-shell droplets in which a core solvent is coated by a shell material.

5. A three-dimensional printing rapid prototyping device for core-shell structure carbon absorption material according to claim 4, characterized in that: The inner diameter of the glass capillary is larger than the outer diameter of the stainless steel needle; the inner diameter of the glass square tube is 1.1 mm and larger than the outer diameter of the glass capillary by 0.1 mm; The glass capillary extends to one side of the position of the flat-head needle and is 3-4 mm away from the outlet of the glass square tube.

6. A three-dimensional printing rapid prototyping device for a core-shell carbon absorbent material according to claim 4, characterized in that: The stainless steel point needle, T-shaped three-way pipe plastic joint, glass capillary, glass square tube, flat-head needle and glass sheet are sealed with epoxy resin.

7. A three-dimensional printing rapid prototyping device for a core-shell structure carbon absorbent material according to claim 4, characterized in that: The glass capillary and the stainless steel needle were treated with hydrophobicity by soaking in an oil film cleaner for 8 hours, and the glass square tube was treated with oleophobicity by soaking in 5wt% PVA for 1 hour to prevent the coaxial flow micro-scale channel from being blocked during the flow process.

8. A three-dimensional printing rapid prototyping method for a core-shell structure carbon absorber material implemented by the prototyping device according to any one of claims 1 to 7, characterized in that: The method comprises: (1) dissolving sodium carbonate in distilled water, adding amine as an additive, and adding phenolphthalein dye, and mixing them into a binary system by ultrasonic oscillation at an oscillation frequency of 40 kHz and a temperature of 293.15 K for 20 min to obtain a core solvent; (2) adding 1 wt% to 5 wt% of nano-magnetic particles to a photocurable resin TEGO Rad 2650 having a high air permeability, stirring the mixture at a speed of 1000 r / min and a temperature of 293.15 K for 10 min in a dark environment to obtain a shell material; (3) dissolving glycerol in distilled water and adding surfactant polyvinyl alcohol, stirring at a speed of 600 r / min and a temperature of 343.15 K for 15 min to obtain an external phase solution; (4) placing the core solvent, shell material, and external phase solution into a syringe pump respectively, and connecting the corresponding microinjectors to the inner phase microfluidic channel, the intermediate phase microfluidic channel, and the external phase microfluidic channel of the coaxial flow microscale channel respectively; (5) The coaxial flow microscale channel is fixed on the mobile print head through a three-dimensional numerical control printing platform, and the movement of the mobile print head on the XYZ axis of the three-dimensional numerical control printing platform is controlled by a numerical control board connected to a computer. The coaxial flow microscale channel controls the flow of materials, and the corresponding micro-injector is controlled by adjusting the parameters of the injection pump to slowly inject the core solvent, shell material and external phase solution into the inner phase microfluidic channel, the intermediate phase microfluidic channel and the external phase microfluidic channel, and the amount of material in each layer is adjusted by the injection pump. At the same time, the three-dimensional numerical control printing platform is controlled by a computer to further control the position and generation rate of material generation, and the arrangement mode is adjusted to realize three-dimensional printing. First, the first The first-stage T-shaped structure generates core droplets through a stainless steel point needle as the intermediate phase inlet, a T-shaped three-way pipe plastic joint as the inner phase inlet and a glass capillary; the second-stage coaxial flow structure generates core-shell droplets composed of a shell material and a core solvent through a glass square tube, a glass sheet and a flat-headed needle as the outer phase inlet. After the droplets are stably generated, an ultraviolet lamp is used to irradiate symmetrically on both sides of the bottom of the receiving container to induce the surface of the droplets to polymerize to form separate core-shell microspheres, or to bond with the previously formed microspheres. Each time a layer of resin is irradiated, a solid layer is formed. The object is constructed by stacking layer by layer, and the core-shell structures are cross-linked and bonded to each other to prepare cross-linked core-shell structured carbon absorption materials of different shapes.

9. The three-dimensional printing rapid prototyping device of the core-shell structure carbon absorption material according to claim 8, characterized in that: In (5), the injection speed of the injection pump is controlled so that the inner phase flow rate is 10-20 μL / min, the middle phase flow rate is 10-20 μL / min, and the outer phase flow rate is 400-800 μL / min, and the coaxial flow microscale channel movement speed is adjusted between 0-1 mm / s using a three-axis CNC printing platform and a computer.

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