CN115253893A - A kind of supercritical carbon dioxide preparation device and method for a small amount of nano-polar particles - Google Patents

Abstract

The invention discloses a supercritical carbon dioxide preparation device and a supercritical carbon dioxide preparation method for a small number of nano-polar particles, wherein the output end of a CO2 gas source module of the device is communicated with the input end of a cooling module, and the output end of the cooling module is communicated with the input end of a CO2 pressurizing module; the circulating cooling module is communicated with the cooling module; the solvent pressurizing module comprises a glass bottle, a solvent metering pump and a liquid displacer; one end of the solvent metering pump is communicated with the glass bottle, and the other end of the solvent metering pump is communicated with one end of the liquid displacer; the other end of the liquid displacer is communicated with the granulation module; the input end of the granulation module is respectively connected with the output ends of the CO2 pressurizing module and the solvent pressurizing module, and the output end of the granulation module is communicated with the outside after passing through the buffering and discharging module. Through the targeted optimization of modules and processes, the device can realize the preparation, recovery and collection of nanoparticles by using a small amount of nano-polar materials. The risk of carbon dioxide asphyxiation in the room caused by overpressure and sealing failure of the device can be reduced.

Description

A kind of supercritical carbon dioxide preparation device and method of a small amount of nano polar particles

technical field

The invention relates to the technical field of functional material preparation instruments, in particular to a supercritical carbon dioxide preparation device and method for a small amount of nano polar particles.

Background technique

Traditional methods for preparing nanoparticles include spray drying after emulsification, cooling vacuum drying, mechanical crushing, mechanical grinding, etc., but these methods have certain problems, such as the impurity introduced in the process cannot be removed, the activity of raw materials is damaged, and the particles Wide particle size distribution, etc. The critical temperature (31.1°C) and critical pressure (7.38Mpa) of supercritical carbon dioxide fluid are low, non-toxic, non-corrosive, non-flammable, and low in price. The density of supercritical carbon dioxide fluid is close to that of liquid, and its viscosity is close to the special physical state of gas. It changes sharply with the change of pressure and temperature. It has excellent fluidity and transfer performance, and is especially suitable for heat-sensitive substances (such as drugs, Granulation treatment of biological extracts). Supercritical carbon dioxide fluid technology in the direction of particle preparation, based on the molecular polarity of the material to be granulated, there are two types of methods, namely supercritical carbon dioxide rapid expansion method and supercritical carbon dioxide anti-solvent method.

Based on the principle that like dissolves like, since polar substances are basically insoluble in non-polar supercritical carbon dioxide fluid, a solvent capable of dissolving supercritical carbon dioxide fluid can be selected to dissolve the substance. When the supercritical carbon dioxide fluid as an anti-solvent is in full contact with the solution, the supercritical carbon dioxide fluid rapidly diffuses into the solution, the volume of the solution expands, the density decreases, the solubility decreases, and the solution is supersaturated to nucleate and precipitate solute particles. Fundamentals of the critical carbon dioxide antisolvent method.

Mechanism of action: Drugs (such as chemotherapy drugs or blood dyes) that need to reach organs and tissues along with the blood generally contain polar functional groups in their molecular structure, such as sulfonic acid (-SO ₃ H), carboxyl (-COOH), hydroxyl (-OH ), the molecules of these drugs are polar. Therefore, when using supercritical carbon dioxide fluid to prepare "polar particles", the supercritical carbon dioxide anti-solvent method is generally used.

In the scientific research and application in colleges and universities, enterprise scientific research departments, and medical places, polar substances that need to be granulated are often very expensive or difficult to obtain in large quantities, but high-frequency, small-batch granulation is often required. Therefore, when using a supercritical carbon dioxide granulation device, it is necessary for the device and method to be able to granulate with a small amount of material, and the granulated material can be collected. In addition, when using a supercritical carbon dioxide granulation device, the above-mentioned scientific research personnel are mostly in an indoor environment, and it is necessary to prevent the leakage of high-pressure carbon dioxide gas and cause the risk of hypoxia and suffocation.

There are disadvantages in the prior art as follows:

(1) At present, when preparing "polar particles", when using the supercritical carbon dioxide anti-solvent method, it is necessary to dissolve the polar substance in the solvent, and then pressurize the pump to reach a certain flow rate and enter the high-pressure granulation tank. The experiment is over Nano polar particles are then collected. Since the pump operation requires the liquid to fill the pump head, and there is no suitable method for the liquid to reach a certain flow rate for a small amount of liquid from the pump to the high-pressure granulation tank. This leads to the current device and method requiring a large amount of polar substances to be dissolved and equipped before granulation to meet the operation of the pump and the high flow rate of the liquid sprayed at the nozzle. Due to the small particle size of the nano-polar particles, it is easy for the carbon dioxide fluid to carry and pass through the buffer discharge module during the granulation process, and the particles deposited on the inner and outer walls after the granulation are not easy to be collected. This further leads to the fact that when a certain amount of nano-polar particles is required, a large amount of polar substances need to be dissolved and equipped before granulation.

(2) At present, when the supercritical carbon dioxide anti-solvent method is used to prepare polar particles, carbon dioxide leakage will occur when the device is overpressured and the sealing element fails. When the leakage of carbon dioxide is not detected in time, the lack of vigilance of personnel will lead to the risk of asphyxiation due to hypoxia. At present, there are two kinds of seals for the detachable high-pressure granulation tank of the supercritical carbon dioxide granulation device. The first one is a PTFE flat gasket + flange sealing structure. This solution is safe to seal, but the operation is cumbersome and the The required torque is as high as about 15N·m. The second is to use fluorine rubber or polyurethane polymer O-ring + sealing groove structure. This solution is easy to operate, but during use, this type of O-ring is dissolved and leaked by carbon dioxide, resulting in bad indoor space. Safety and Experimental Failure. In the current granulation technology of supercritical carbon dioxide anti-solvent method, how to avoid overpressure, seal failure and suffocation risk of leaking gas, there is no suitable improvement plan reported at present.

The invention patent application with the publication number CN103623746 discloses a supercritical-solvothermal combination device and method for preparing nanomaterials. The application adjusts the valve switch combination, raw material placement method, and entrainer entry method through splicing pipelines and components. Conditions or parameters, that is, a variety of supercritical-solvothermal combination preparation methods can be realized, which can meet the preparation of organic nanomaterials, inorganic nanomaterials and organic/inorganic composite nanomaterials. But the above problem is still not solved.

Contents of the invention

The object of the present invention is to provide a kind of supercritical carbon dioxide preparation device and method of a small amount of nano-polar particles. The flow rate of the liquid at the nozzle and the recovery and collection of enough nanoparticles after the experiment require a large number of equipment to dissolve a large number of polar solutes. In addition, when supercritical carbon dioxide fluid is used for indoor scientific research to prepare nano-polar particles, the risk of indoor carbon dioxide suffocation caused by device overpressure and seal failure is prone to occur.

In order to solve the above technical problems, the present invention provides the following technical solutions:

A supercritical carbon dioxide preparation device for a small amount of nano-polar particles, including a CO2 gas source module, a cooling module, a circulation cooling module, a CO2 pressurization module, a solvent pressurization module, a granulation module and a buffer release module;

The output end of the CO2 gas source module is communicated with the input end of the cooling module, and the output end of the cooling module is communicated with the input end of the CO2 booster module; the circulation cooling module is communicated with the cooling module;

The solvent pressurization module includes a glass bottle, a solvent metering pump, and a liquid displacer; one end of the solvent metering pump communicates with the glass bottle, and the other end communicates with one end of the liquid displacer; the other end of the liquid displacer communicates with the component Granular module connectivity;

The input ends of the granulation module are respectively connected with the output ends of the CO2 pressurization module and the solvent pressurization module, and the output ends communicate with the outside after passing through the buffer release module.

Advantages: The present invention can realize the preparation and recycling of nano particles with a small amount of nano polar materials through targeted optimization of modules and processes. And when supercritical carbon dioxide fluid is used in indoor scientific research to prepare nano-polar particles, it can reduce the risk of indoor carbon dioxide suffocation caused by device overpressure and seal failure.

Preferably, the liquid displacer includes a displacement cylinder, a front screw cap, a rear screw cap, a movable block, and a first spring energy storage sealing ring;

The replacement cylinder is a cylindrical structure with upper and lower openings, and the upper and lower ends of the replacement cylinder are stepped;

The front screw cap can be matched and installed on the upper end of the replacement cylinder, and the rear screw cap can be matched and installed on the lower end of the replacement cylinder; between the replacement cylinder and the front screw cap, between the replacement cylinder and the rear The first spring energy storage sealing ring is installed between the end screw caps;

A movable block is arranged inside the replacement cylinder, and the movable block divides the inner space of the replacement cylinder into a first cavity and a second cavity;

The front screw cap is provided with a driving solution inlet, and the driving solution inlet is connected with the first cavity containing the driving solution; the driving solution inlet is connected with a solvent metering pump;

The rear screw cap is provided with a replacement solution outlet, the replacement solution outlet communicates with the second cavity containing the replacement solution, and the replacement solution outlet communicates with the high-pressure granulation tank.

Preferably, the liquid displacer further includes an O-ring; the O-ring is mounted on the peripheral side of the movable block.

Preferably, the granulation module includes a high-pressure granulation tank and an annular heater; the annular heater is installed on the side wall of the high-pressure granulation tank;

The upper end of the high-pressure granulation tank is connected to the liquid displacer, and the lower end is connected to the buffer and discharge module;

The high-pressure granulation tank includes a high-pressure deposition kettle body, a deposition chamber kettle cover, a second spring energy storage sealing ring, a polytetrafluoroethylene liner and a filter core plate;

The high-pressure deposition kettle body is a cylindrical structure with a sealed lower end, the upper end of the inner wall of the high-pressure deposition kettle body is stepped, the lid of the deposition chamber is stepped, and the lid of the deposition chamber can be matched and installed on the high-pressure deposition kettle body;

The second spring energy storage sealing ring is installed between the high-pressure deposition kettle body and the deposition chamber kettle cover;

The polytetrafluoroethylene liner is arranged on the inner wall of the high-pressure deposition kettle, and the lower end of the inner wall of the high-pressure deposition kettle is provided with a filter plate, and the bottom of the high-pressure deposition kettle is provided with an air outlet; the lid of the deposition chamber is provided with two A liquid inlet connecting the outside and the inside of the deposition chamber.

Preferably, the nozzle is made of metal, and the inner diameter of the nozzle channel is between 0.05 mm and 0.25 mm.

Preferably, the second spring energy-storing sealing ring adopts PTFE (polytetrafluoroethylene) material as the base material, and the lip is semicircular or V-shaped. A helically wound metal spring is supported inside a semicircular or V-shaped PTFE to provide the initial sealing force required for sealing under normal and low pressures.

Preferably, a control module is also included, and the control module includes a PLC controller, a first temperature sensor, a second temperature sensor, a first pressure sensor, a second pressure sensor, and a CO2 detector;

The first temperature sensor is installed at the annular heater, and the second temperature sensor is installed in the high-pressure granulation tank;

The first pressure sensor is installed in the high-pressure granulation tank, and the second pressure sensor is installed in the pipeline between the high-pressure granulation tank and the buffer tank;

The CO2 detector is installed in the device, exposed to the atmospheric environment, and detects the CO2 concentration in the indoor air;

The signals of the first temperature sensor, the second temperature sensor, the first pressure sensor, the second pressure sensor and the CO2 detector are all processed and displayed on the PLC controller.

The present invention also discloses a method for using the above-mentioned supercritical carbon dioxide preparation device with a small amount of nano-polar particles, comprising the following steps:

S1. Fully mix the solute and solvent to form a uniform solution, and move it to the side of the liquid displacer close to the high-pressure granulation tank. Transfer the ethanol to a glass vial.

S2. Install the single-channel nozzle under the lid of the deposition chamber, place the PTFE liner and the filter plate in the high-pressure deposition kettle body, and manually twist the lid of the deposition chamber until the second spring energy storage sealing ring falls to the bottom of the deposition chamber. Inside the kettle.

S3. After setting the target temperature and target pressure, the carbon dioxide gas is condensed into a liquid state by the condenser, pressurized by the metering pump, and the pipeline behind the pump is electrically heated, and then enters the high-pressure granulation tank. The control system makes the high-pressure granulation tank reach the target temperature and target pressure by adjusting the flow rate and starting and stopping of the metering pump through the first temperature sensor and the first pressure sensor.

S4. Turn on the solvent metering pump, and pump the ethanol in the glass bottle into the side of the liquid displacer away from the high-pressure granulation tank. Through the movable block in the liquid displacer, the solution containing raw materials is pushed into the high-pressure granulation tank;

S5. After the reaction, the pressure was released to normal pressure, the temperature was naturally lowered to room temperature, and the lid of the deposition chamber was manually twisted to collect the nano-polar particles of the target product from the PTFE lining and the filter core plate.

S6. During the above process, if the CO2 detector detects that the CO2 concentration in the indoor air is abnormal, then control the chain sound and light alarm and shut down the power supply.

Preferably, the solvent has a dielectric constant (dielectric constant) of 5-21 at room temperature, including at least one of dichloromethane, ether, and acetone.

Preferably, the molecular structure of the solute contains strong polar functional groups, including at least one of sulfonic acid group (-SO ₃ H), carboxyl group (-COOH), and hydroxyl group (-OH).

Compared with prior art, the beneficial effect of the present invention is:

(1) Through the targeted optimization of modules and processes, the present invention can realize the preparation and recycling of nanoparticles using a small amount of nano-polar materials. And when supercritical carbon dioxide fluid is used in indoor scientific research to prepare nano-polar particles, it can reduce the risk of indoor carbon dioxide suffocation caused by device overpressure and seal failure.

(2) The movable block of the liquid displacer of the present invention divides the interior into two cavities, the first cavity and the second cavity, for containing the drive solution and the replacement solution respectively. Since the solvent metering pump reaches a certain flow rate after being pressurized by the pump, and the operation of the pump requires liquid to fill the pump head, a large amount of solution is required to ensure the operation of the pump. The present invention squeezes the replacement solution to the small-sized single-channel nozzle of the high-pressure granulation tank through a large amount of cheap or easy-to-obtain drive solution, and sets recovery components, so the liquid displacer can realize the use of a small amount of nano-polar substances for preparation and collected.

(3) The high-pressure granulation tank of the present invention adopts a high-pressure self-tightening seal structure, which is simple in structure and greatly facilitates the sealing installation of the high-pressure granulation tank, and the pre-tightening force of about 15N m required by traditional bolt sealing is reduced to about 1N ·m, without using tools, ordinary adults can open and close with bare hands, which can meet the sealing requirements. Combined with the safety interlocking of _CO2 detectors and pressure sensors, it also reduces the risk of indoor carbon dioxide suffocation caused by device overpressure and seal failure.

Description of drawings

Fig. 1 is the block diagram that the device of the embodiment of the present invention forms;

Fig. 2 is the process and instrument flow chart of the embodiment of the present invention;

Fig. 3 is a schematic structural connection diagram of a liquid displacer according to an embodiment of the present invention;

Fig. 4 is the structural connection schematic diagram of the high pressure granulation tank of the embodiment of the present invention;

Fig. 5 is a functional schematic diagram of the lid of the deposition chamber according to the embodiment of the present invention.

Detailed ways

In order to facilitate those skilled in the art to understand the technical solution of the present invention, the technical solution of the present invention will be further described in conjunction with the accompanying drawings.

The terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of the present application, "plurality" means two or more, unless otherwise specifically defined.

Referring to Fig. 1 and Fig. 2, the present embodiment discloses a kind of supercritical carbon dioxide preparation device of a small amount of nano-polar particles, including _CO gas source module 1, cooling module 2, circulation cooling module 3, _CO booster module 4, Solvent pressurization module 5 , granulation module 6 , buffer discharge module 7 and control module 8 .

The CO ₂ gas source module 1 is a CO ₂ cylinder 11, and at room temperature (20°C/293.15K), the internal pressure of the CO ₂ cylinder 11 is 57.2 bar. The phase state of _CO2 in the steel cylinder is gaseous and liquid coexistence, the gaseous state is at the top, and the liquid is at the bottom.

Simultaneously, the cooling module 2 adopts a condenser 21; the circulation cooling module 3 adopts a refrigerating cycle machine 31; the _CO booster module 4 adopts a _CO metering pump 41; the solvent booster module 5 includes a glass bottle 51, a solvent metering pump 52, a liquid replacement device 53; the granulation module 6 includes a high-pressure granulation tank 61 and an annular heater 62; the buffer release module 7 includes a buffer tank 71.

The output end of the _CO2 steel cylinder 11 communicates with the input end of the condenser 21 after passing through the first ball valve, the output end of the condenser 21 communicates with the input end of the _CO2 metering pump 41 after passing through the second ball valve, and the output end of the _CO2 metering pump 41 The end is connected to the upper end of the high-pressure granulation tank 61. The refrigerating cycle machine 31 communicates with the condenser 21 for continuous heat exchange in the condenser 21 to cool the gaseous CO ₂ into liquid CO ₂ .

One end of the solvent metering pump 52 communicates with the glass bottle 51 , and the other end communicates with one end of the liquid displacer 53 ; the other end of the liquid displacer 53 is connected to the upper end of the high-pressure granulation tank 61 . The lower end of the high-pressure granulation tank 61 is connected to the input end of the buffer tank 71 after passing through the electromagnetic valve, and the output end of the buffer tank 71 is communicated with the atmosphere. The ring heater 62 is installed on the side wall of the high-pressure granulation tank 61 .

Referring to FIG. 3 , the liquid displacer 53 of this embodiment includes a displacement cylinder 531 , a front screw cap 532 , a rear screw cap 533 , a movable block 534 and a first spring energy storage sealing ring 535 .

The replacement cylinder 531 is a cylindrical structure with upper and lower openings. The upper and lower ends of the replacement cylinder 531 are stepped. The front screw cap 532 can be fitted on the upper end of the replacement cylinder 531 , and the rear screw cap 533 can be fitted on the lower end of the replacement cylinder 531 . Between the replacement cylinder 531 and the front screw cap 532 , and between the replacement cylinder 531 and the rear screw cap 533 , a first spring energy storage sealing ring 535 is installed. A movable block 534 is disposed inside the replacement cylinder 531, and the movable block 534 divides the inner space of the replacement cylinder 531 into a first cavity for containing the driving solution and a second cavity for containing the replacement solution. An O-ring 5341 is also provided on the peripheral side of the movable block 534, which can ensure that the solution in the first cavity and the solution in the second cavity will not merge. The upper and lower ends of the replacement cylinder 531 are provided with first explosion-proof relief holes 5311 .

The front screw cap 532 is provided with a driving solution inlet 5321, which communicates with the first cavity containing the driving solution for transporting the driving solution, and the driving solution inlet 5321 communicates with the solvent metering pump. The replacement solution outlet 5331 communicates with the second cavity containing the replacement solution, and is used to output the replacement solution, and the replacement solution outlet 5331 communicates with the high-pressure granulation tank 61 .

The movable block 534 of the liquid displacer in this embodiment divides the interior into two cavities, the first cavity and the second cavity, for containing the drive solution and the replacement solution respectively. Since the solvent metering pump 52 reaches a certain flow rate after being pressurized by the pump, and the pump operation requires liquid to fill the pump head, a large amount of solution is required to ensure the operation of the pump. In this embodiment, an inexpensive drive solution such as water is provided in the glass bottle 51, and the drive solution is transported from the glass bottle 51 through the solvent metering pump 52 to the first chamber of the liquid displacer 53 containing the drive solution. With the injection of the drive solution, The movable block 534 can be driven to move toward the second cavity containing the replacement solution, and the replacement solution in the second cavity can be squeezed into the high-pressure granulation tank 61 . Therefore, the liquid displacer 53 can be prepared using a small amount of nano-polar substances.

In this way, cheap or easily obtained drive solution is used to ensure the operation of the pump, so even if a large amount of drive solution is consumed, only a very low cost is required, and there is no need to prepare a large amount of polar substances in advance, saving time. Referring to FIG. 4 , the high-pressure granulation tank 61 of this embodiment specifically includes a high-pressure deposition tank body 611 , a deposition chamber cover 612 , a second spring energy storage sealing ring 613 , a polytetrafluoroethylene liner 614 , a filter core plate 615 and a nozzle 616 .

The high-pressure deposition kettle body 611 is a cylindrical structure with a sealed lower end. The upper end of the inner wall of the high-pressure deposition kettle body 611 is stepped. The deposition chamber lid 612 is stepped. The deposition chamber lid 612 can be mounted on the high-pressure deposition kettle body 611. The second spring energy storage sealing ring 613 is installed between the high-pressure deposition kettle body 611 and the deposition chamber kettle cover 612 . The inner wall of the high-pressure deposition kettle body 611 is sprayed with Teflon to form a polytetrafluoroethylene lining 614, the lower end of the inner wall of the high-pressure deposition kettle body 611 is provided with a filter plate 615, and the bottom of the high-pressure deposition kettle body 611 is provided with an air outlet 6112; the deposition chamber lid 612 There are three liquid inlets 6121 connecting the outside and the interior of the deposition chamber. Liquid CO2 enters the interior of the high-pressure deposition kettle body 611 through one of the liquid inlets 6121, and the solution in the liquid displacer 53 enters the high-pressure deposition through the other liquid inlet 6121. Inside the kettle body 611, the last corresponding sensor extends into the high-pressure granulation tank 61 through the last liquid inlet 6121 for measurement. The upper end of the high pressure deposition tank body 611 is provided with a first explosion-proof relief hole 6111 .

In this embodiment, a replaceable polytetrafluoroethylene liner 614 and a filter core plate 615 are arranged in the high-pressure deposition kettle body 611. On the one hand, particles can be adhered to the metal inner wall of the high-pressure deposition kettle body 611; The particles on the inner liner 614 and the filter core plate 615 are taken out, making it easier to recycle the granulated particles. At the same time, the filter core plate 615 is arranged on the upper end of the gas outlet 6112, and the formed particles can be retained while letting the gas escape.

The nozzle 616 is made of metal, and the inner diameter of the nozzle channel is between 0.05 mm and 0.25 mm. Nozzle 616 is a single channel nozzle that prevents backflow of liquid. At the same time, the nozzle 616 of this embodiment adopts a small nozzle, and the injection speed is fast under the same flow rate, and it is easier to spray the delivered replacement solution, and it is easier to granulate in the high-pressure granulation tank 61 .

The second spring-energy-storage sealing ring 613 of this embodiment adopts PTFE (polytetrafluoroethylene) material as the base material, and the lip is semicircular or V-shaped. PTFE (polytetrafluoroethylene) material as the base material has good chemical inertness and good temperature resistance. The operating temperature is +260 ° C ~ -196 ° C. It has no hardness requirements on the working surface and can be used for reciprocating rotation. , Prolong the service life of the sealing ring while ensuring the sealing effect. In terms of sealing performance, the second spring energy storage sealing ring 613 is used to integrate the high-pressure deposition kettle body 611 and the deposition chamber kettle cover 612. When the second spring energy storage sealing ring 613 is at low pressure and zero pressure, the initial sealing force is determined by the metal When the system pressure rises, the main sealing force is formed by the system pressure, so it cannot guarantee good sealing performance from zero pressure to high pressure. The design of the threaded quick-opening high-pressure self-tightening seal is simple and easy to understand, and the operation is convenient, which not only meets the requirements for safe and reliable operation, but also solves the technical problem of quick-opening. This sealing structure greatly facilitates the sealing installation of the high-pressure granulation tank 61, and the pre-tightening force of about 15N.m required by the traditional bolt seal is reduced to about 1N.m, and ordinary adults can do it by hand without using tools. Opening and closing can meet the sealing requirements.

The control module 8 of this embodiment includes a PLC controller (not shown), a first temperature sensor 81 , a second temperature sensor 82 , a first pressure sensor 83 , a second pressure sensor 84 , and a CO2 detector 85 .

The first temperature sensor 81 is installed in the annular heater 62 places, and the second temperature sensor 82 is installed in the high-pressure granulation tank 61; The first pressure sensor 83 is installed in the high-pressure granulation tank 61, and the second pressure sensor 84 is installed in the high-pressure granulation tank 61 In the pipeline between the particle tank 61 and the buffer tank 71; CO2 detector 85 is installed in the buffer tank 71; the first temperature sensor 81, the second temperature sensor 82, the first pressure sensor 83, the second pressure sensor 84 and CO2 detection The devices 85 are all connected to the input end of the PLC controller, and the first ball valve, the second ball valve and the solenoid valve are all connected to the output end of the PLC controller. By arranging the _CO2 detector 85 outside the buffer tank 71, the _CO2 concentration in the air outside the device can be detected, the _CO2 leakage caused by the failure of some parts of the device can be sensed, and then the personnel can be reminded.

In this embodiment, by setting the control module 8, on the one hand, in order to precisely control and stabilize the system temperature and system pressure, so as to accurately control the stability of the supercritical carbon dioxide system; on the other hand, in order to make the whole equipment more intelligent and convenient.

Specifically, the control module 8 of this embodiment is designed and optimized in the control system in this development. The architecture and scheme mainly include: intelligent hardware system, central processing unit operation control system, and human-computer interaction system.

Intelligent hardware system: For the above-mentioned booster equipment, pressure sensor and temperature sensor, etc., it is necessary to select the appropriate communication signal.

In order to improve the temperature control accuracy, the type of input sensor is reasonably selected, and the output control model uses analog output mode, which has better control accuracy. The temperature control algorithm adopts PID self-adjustment to precisely adjust the temperature control accuracy.

Central processor operation control system: the central processor industrial-grade PLC control system unit, through the international standard LAD and SCL language for precise data processing and logic operations, high system stability; through the linkage process control of pressure sensors and booster equipment, With the system micro-adjustment unit, at the set pressure (MPa) value, the central processor realizes the process control of the booster equipment according to the conversion of the system pressure and the set pressure and the dynamic comparison of the process. The control system pressure has high overall precision and small error.

Human-computer interaction system: This control module 8 adopts a resistive touch screen. After setting important parameters (flow ml/min, pressure MPa, temperature ℃, etc.), switch the system to automatic working mode to realize unattended and automatic The temperature is adjusted by PID, the pressure process is controlled and adjusted, so that the system can run stably for a long time in a stable and high-level state, improve the efficiency of the experiment, and effectively eliminate other interference factors.

This embodiment also discloses a preparation method using the device, and the specific operation process is as follows:

(1) The solute "paclitaxel" and the solvent "acetone" are thoroughly mixed to form a uniform solution (about 4ml), and moved to the side of the liquid displacer 53 close to the high-pressure granulation tank 61. Transfer ethanol to glass bottle 51.

(2) Clean and dry the single channel nozzle 616 to prevent clogging. Install the single-channel nozzle 616 under the deposition chamber lid 612, place the polytetrafluoroethylene liner 614 and the filter core plate 615 in the high-pressure deposition kettle body 611, and manually twist the deposition chamber lid 612 to the second spring energy storage Sealing ring 613 falls in still body.

(3) After setting the experimental target temperature (80.0°C) and target pressure (20.0Mpa) of the high-pressure granulation tank of this experiment on the touch screen of the device, the carbon dioxide gas is condensed into a liquid state by the condenser 21, and then the gas is condensed into a liquid state by the metering pump. 41. The pipeline after the pressurization and pump is electrically heated, and the setting temperature of the electric tracing belt is also 80.0°C. Enter the high-pressure granulation tank 61. The control system uses the first temperature sensor 81 and the first pressure sensor 83 to adjust the flow and start and stop of the metering pump 41 to make the high-pressure granulation tank 61 reach the target temperature and pressure, and stabilize for 5-10 minutes.

S4. Calculate the required flow rate of the solvent metering pump 52 according to the diameter of the single-channel nozzle 616 , the required flow rate of the jet stream, and the inner diameter of the liquid displacer 53 . Set the flow rate, start and open the solvent metering pump 52, and pump the ethanol in the glass bottle 51 into the side of the liquid displacer 53 away from the high-pressure granulation tank 61. Through the movable block 533 in the liquid displacer 53, the solution containing the solute is pushed into the high-pressure granulation tank 61;

S5, after the reaction is over, release the pressure to normal pressure, naturally cool down to room temperature, manually twist the lid 612 of the deposition chamber, and collect the target product nanometer electrode from the polytetrafluoroethylene lining 614 and the filter core plate 615 with a tool made of quartz glass. sex particles.

S6. During the above process, if the PLC control system detects that the temperature, pressure, and _CO2 gas concentration are abnormal, the control system will automatically interlock sound and light alarms and shut down the power supply.

It will be apparent to those skilled in the art that the invention is not limited to the details of the above-described exemplary embodiments, but that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Accordingly, the embodiments should be regarded in all points of view as exemplary and not restrictive, the scope of the invention being defined by the appended claims rather than the foregoing description, and it is therefore intended that the scope of the invention be defined by the appended claims rather than by the foregoing description. All changes within the meaning and range of equivalents of the elements are embraced in the invention, and any reference sign in a claim shall not be construed as limiting the claim concerned.

The above-described embodiments only represent the implementation of the invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments. For those skilled in the art, some deformations and changes can also be made without departing from the concept of the present invention. Improvements, these all belong to the protection scope of the present invention.

Claims (10)

1. A supercritical carbon dioxide preparation device of a small amount of nanometer polar particles is characterized in that: the device comprises a CO2 gas source module (1), a cooling module (2), a circulating cooling module (3), a CO2 pressurizing module (4), a solvent pressurizing module (5), a granulation module (6) and a buffer discharging module (7);

the output end of the CO2 gas source module (1) is communicated with the input end of the cooling module (2), and the output end of the cooling module (2) is communicated with the input end of the CO2 pressurizing module (4); the circulating cooling module (3) is communicated with the cooling module (2);

the solvent pressurization module (5) comprises a glass bottle (51), a solvent metering pump (52) and a liquid displacer (53); one end of the solvent metering pump (52) is communicated with the glass bottle (51), and the other end of the solvent metering pump is communicated with one end of the liquid displacer (53); the other end of the liquid displacer (53) communicates with the granulation module (6);

the input end of the granulation module (6) is respectively connected with the output ends of the CO2 pressurizing module (4) and the solvent pressurizing module (5), and the output end is communicated with the outside after passing through the buffering and discharging module (7).

2. The apparatus for preparing supercritical carbon dioxide with small amount of nano-polar particles as claimed in claim 1, wherein: the liquid displacer comprises a displacement cylinder body (531), a front-end screw cap (532), a rear-end screw cap (533), a movable block (534) and a first spring energy storage sealing ring (535);

the replacement cylinder body (531) is of a cylindrical structure with an upper opening and a lower opening, and the upper end and the lower end of the interior of the replacement cylinder body (531) are both stepped;

the front end screw cap (532) can be arranged at the upper end of the replacement cylinder body (531) in a matching way, and the rear end screw cap (533) can be arranged at the lower end of the replacement cylinder body (531) in a matching way; first spring energy storage sealing rings (535) are arranged between the replacement cylinder body (531) and the front end screw cap (532) and between the replacement cylinder body (531) and the rear end screw cap (533);

a movable block (534) is arranged inside the replacement cylinder (531), and the movable block (534) divides the inner space of the replacement cylinder (531) into a first cavity and a second cavity;

a driving solution inlet (5321) is formed in the front-end screw cap (532), and the driving solution inlet (5321) is communicated with a first cavity for containing a driving solution; the driving solution inlet (5321) is communicated with a solvent metering pump;

the rear end screw cap (533) is provided with a replacement solution outlet (5331), the replacement solution outlet (5331) is communicated with the second cavity for containing the replacement solution, and the replacement solution outlet (5331) is communicated with the high-pressure granulation tank.

3. The apparatus for preparing supercritical carbon dioxide with small amount of nano-polar particles as claimed in claim 2, wherein: the liquid displacer further includes an O-ring seal (5341); the O-shaped sealing ring (5341) is mounted on the periphery of the movable block (534).

4. The apparatus for preparing supercritical carbon dioxide with small amount of nano-polar particles as claimed in claim 1, wherein: the granulation module (6) comprises a high pressure granulation tank (61) and a ring heater (62);

the high-pressure granulation tank (61) comprises a high-pressure sedimentation kettle body (611), a sedimentation chamber kettle cover (612), a second spring energy storage sealing ring (613), a polytetrafluoroethylene lining (614), a filter element plate (615) and a nozzle (616);

the high-pressure deposition kettle body (611) is of a cylindrical structure with the lower end sealed, the upper end of the inner wall of the high-pressure deposition kettle body (611) is in a step shape, the deposition chamber kettle cover (612) is in a step shape, and the deposition chamber kettle cover (612) can be installed on the high-pressure deposition kettle body (611) in a matched mode;

the second spring energy storage sealing ring (613) is arranged between the high-pressure deposition kettle body (611) and the deposition chamber kettle cover (612);

the polytetrafluoroethylene lining (614) is arranged on the inner wall of the high-pressure deposition kettle body (611), the filter plate (615) is arranged at the lower end of the inner wall of the high-pressure deposition kettle body (611), and the air outlet (6112) is formed in the bottom of the high-pressure deposition kettle body (611);

the deposition chamber kettle cover (612) is provided with three liquid inlets (6121) which are communicated with the outside and the inside of the deposition chamber.

5. The apparatus for supercritical carbon dioxide production of nano-polar particles according to claim 4, wherein: the nozzle (616) is made of metal, and the inner diameter of the channel of the nozzle (616) is between 0.05mm and 0.25 mm.

6. The apparatus for supercritical carbon dioxide production of nano-polar particles according to claim 4, wherein: the second spring energy storage sealing ring (613) is made of PTFE (polytetrafluoroethylene) materials as base materials, and the lip edge is semicircular or V-shaped.

7. The apparatus for supercritical carbon dioxide production of nano-polar particles according to claim 1, wherein: the device is characterized by further comprising a control module (8), wherein the control module (8) comprises a PLC (programmable logic controller), a first temperature sensor (81), a second temperature sensor (82), a first pressure sensor (83), a second pressure sensor (84) and a CO2 detector (85);

the first temperature sensor (81) is mounted at the ring heater (62), the second temperature sensor (82) is mounted within the high pressure granulation tank (61);

the first pressure sensor (83) is installed within the high pressure granulation tank (61), the second pressure sensor (84) is installed within a conduit between the high pressure granulation tank (61) and the buffer tank (71);

the CO2 detector (85) is arranged in the device and can be contacted with the atmospheric environment;

and signals of the first temperature sensor (81), the second temperature sensor (82), the first pressure sensor (83), the second pressure sensor (84) and the CO2 detector (85) are processed and displayed on the PLC.

8. A method for preparing a supercritical carbon dioxide device using a small amount of nano-polar particles as described in any one of claims 1 to 7, comprising: the method comprises the following steps:

s1, fully mixing the solute and the solvent to form a uniform solution, and moving the uniform solution to one side of a liquid displacer (53) close to a high-pressure granulation tank (61). The other solvent was transferred to a glass bottle (51).

S2, installing a single-channel nozzle (616) below a deposition chamber kettle cover (612), placing a polytetrafluoroethylene lining (614) and a filter element plate (615) in a high-pressure deposition kettle body (611), and manually screwing the deposition chamber kettle cover (612) to enable a second spring energy storage sealing ring (613) to descend into the kettle body.

And S3, after the target temperature and the target pressure are set, condensing the carbon dioxide gas into liquid through a condenser (21), pressurizing through a metering pump (41), carrying out electric tracing through a pipeline after the pump, and feeding the liquid into a high-pressure granulation tank (61). The control system brings the high pressure granulation tank (61) to the target temperature and the target pressure by adjusting the flow rate and start and stop of the metering pump (41) by means of the first temperature sensor (81) and the first pressure sensor (83).

S4, opening the solvent metering pump (52), and pumping the ethanol in the glass bottle (51) into the side of the liquid displacer (53) far away from the high-pressure granulation tank (61). Pushing the solute-containing solution into a high pressure granulation tank (61) by means of a movable block (531) in a liquid displacer (53);

and S5, after the reaction is finished, releasing the pressure to normal pressure, naturally cooling to room temperature, manually screwing a deposition chamber kettle cover (612), and collecting target product nano polar particles from the polytetrafluoroethylene lining (614) and the filter core plate (615).

And S6, in the process, if the CO2 detector (85) detects that the concentration of CO2 in the indoor air is abnormal, controlling the interlocking acousto-optic alarm and the power supply to be closed.

9. The method for preparing the supercritical carbon dioxide device with a small amount of nano-polar particles as claimed in claim 8, wherein: the dielectric constant of the solvent at room temperature is 5-21, and the solvent comprises at least one of dichloromethane, diethyl ether and acetone.

10. The method for preparing the supercritical carbon dioxide device with a small amount of nano-polar particles as claimed in claim 8, wherein: the molecular structure of the solute contains strong polar functional groups including at least one of sulfonic acid group (-SO 3H), carboxyl group (-COOH) and hydroxyl group (-OH).

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