CN105771310B - An experimental device and method for extraction and phase equilibrium using pressurized gas that is easily liquefied - Google Patents

Abstract

The invention relates to an experimental device for extracting and balancing by using pressurized and easily-liquefied gas, which comprises a solvent tank, a refrigerator, a high-pressure pump, a balancing tank and a separating tank which are connected in an annular mode sequentially through pipelines, wherein a charging barrel is detachably arranged in the balancing tank, and an extraction area separated by a filter plate is arranged in the charging barrel. The invention also provides an experimental method for extracting and balancing phases by using the pressurized and easily-liquefied gas, aiming at solid materials or liquid materials, the charging barrel is selectively arranged or not arranged in the balancing tank, and the experimental method is suitable for extracting or balancing phases of solid or liquid materials, and has the advantages of simple structure, high experimental efficiency and high measurement precision.

Description

An experimental device for extraction and phase equilibrium using pressurized gas that is easily liquefied and method

Technical field

The invention relates to the technical field of subcritical extraction, in particular to an experimental device and method for extraction and phase equilibrium using pressurized gas that is easily liquefied.

Background technique

Supercritical carbon dioxide has become one of the most commonly used supercritical fluids due to its non-toxic, harmless, low price, and no pollution to the environment. Although supercritical carbon dioxide extraction technology has many advantages, its high operating pressure causes high equipment costs, which limits its industrial application. Therefore, exploring new green, low-consumption and efficient extraction technology has become a research hotspot in the field of extraction in recent years. In recent years, extraction technology using pressurized, easily liquefied gas has gradually developed. This technology is often called "subcritical" extraction technology. As a potential alternative to supercritical extraction technology, subcritical extraction technology has made a lot of progress thanks to the efforts of domestic and foreign scientific researchers. In order to realize the industrialization of subcritical extraction technology and establish its process indicators and equipment design, the extraction behavior of subcritical solvents (gases that are easily liquefied under pressure) is studied, and the key to research is to measure the phase equilibrium parameters during the extraction process. At present, the experimental devices used to study subcritical extraction and phase equilibrium determination have shortcomings such as single function, most of which can only be adapted to a single solid or liquid material, complex device structure, and low efficiency.

Contents of the invention

The purpose of this invention is to propose an experimental device that utilizes pressurized gas that is easily liquefied to perform extraction and phase balance experiments. It can be used for extraction or phase balance experiments of solid or liquid materials. The device has a simple structure, high experimental efficiency, and high measurement accuracy. . At the same time, the invention also provides an experimental method for extraction and phase equilibrium using pressurized gas that is easily liquefied.

In order to achieve the above purpose, the technical solution adopted by the present invention is as follows: an experimental device for extraction and phase equilibrium using pressurized gas that is easily liquefied, including a solvent tank, a refrigerator, a high-pressure pump, and a balance tank that are connected in an annular manner through pipelines in sequence. and a separation tank. Valves for controlling the opening and closing of pipelines are provided between the solvent tank and the refrigerator, between the high-pressure pump and the balance tank, between the balance tank and the separation tank, and between the separation tank and the solvent tank. The balance Both the tank and the separation tank are equipped with water bath jackets. The characteristic is that the balance tank includes a tank body, a top cover and a barrel. The barrel is detachably inserted into the tank body and is pressed and installed on the tank through the top cover. In the tank; the upper and lower ends of the barrel are respectively provided with upper filter plates and lower filter plates. The area between the upper filter plate and the lower filter plate in the barrel constitutes a solid material extraction area. The upper end of the barrel There are liquid distribution holes located on the upper side of the upper filter plate.

According to the above solution, there is also a preheating tank between the high-pressure pump and the balancing tank. The high-pressure pump and the preheating tank are connected through pipelines and valves. The preheating tank and the balancing tank are connected through pipes. The circuit is connected to the valve.

According to the above solution, a buffer tank, a compressor and a condenser are connected in sequence between the separation tank and the solvent tank. The separation tank and the buffer tank are connected through pipelines and valves. The buffer tank is connected to the compressor. They are connected by pipelines and valves, the compressor and the condenser are connected by pipelines and valves, and the condenser and the solvent tank are connected by pipelines and valves.

According to the above solution, a vacuum pump is also included, and the vacuum pump is respectively connected to the balance tank, separation tank, preheating tank, buffer tank and condenser through pipes and valves.

According to the above solution, a sample collector is detachably installed on the bottom of the separation tank through threaded fit, and the sample collector can be optionally installed according to different capacities.

The invention provides a method for performing extraction and phase equilibrium experiments using pressurized gas that is easily liquefied, and is characterized in that it includes the following steps:

Determine whether to install the barrel in the balance tank according to the state of the material being extracted. When the material is solid, install the barrel into the balance tank. When the material is liquid, there is no need to install the barrel into the balance tank;

Start the refrigerator and high-pressure pump to cool the solvent in the solvent tank and then transport it to the balance tank through the high-pressure pump to extract the solute in the balance tank;

The solution with the solute extracted enters the separation tank for separation of the solvent and the solute. The solute is retained in the separation tank, and the solvent is transported to the solution tank again.

According to the above scheme, before the solvent is transported to the balance tank, the solvent is first transported to the preheating tank for preheating.

According to the above scheme, before entering the solvent tank, the solution separated from the separation tank is first buffered by the buffer tank, then pressurized by the compressor, and finally cooled by the condenser before being transported to the solvent tank.

According to the above plan, before starting the refrigerator and high-pressure pump, start the vacuum pump to evacuate the preheating tank, balance tank, separation tank, buffer tank and condenser.

According to the above plan, before starting the refrigerator and high-pressure pump, select a sampler of appropriate capacity and install it at the bottom of the separation tank.

The present invention uses pressurized gas that is easily liquefied to carry out extraction and phase equilibrium experimental devices and methods. A detachable and installable barrel is designed inside the balance tank, and filter plates are provided at both ends of the barrel, so that the filter plate inside the barrel The extraction area is formed between them. When extracting solid materials, the materials can be directly put into the extraction area of the barrel, and then the barrel is put into the balance tank for the extraction process; when extracting liquid materials, the materials can be The cartridge is taken out of the balance tank, and the internal space of the balance tank is directly used as the extraction area to extract the material. Therefore, the experimental device and method of the present invention can be applied to extraction or phase equilibrium experiments of solid or liquid materials. The device has a simple structure, high experimental efficiency, and high measurement accuracy.

Description of drawings

Figure 1 is a schematic structural diagram of the present invention;

Figure 2 is a schematic structural diagram of the balance tank of the present invention;

Figure 3 is a schematic structural diagram of the barrel of the balance tank of the present invention;

Figure 4 is a schematic diagram of the assembly structure of the balance tank of the present invention;

Figure 5 is a schematic structural diagram of the separation tank of the present invention.

In the picture: 10. Solvent tank; 20. Refrigerator; 30. High-pressure pump; 40. Balance tank; 50. Separation tank; 60. Preheating tank; 70. Buffer tank; 80. Compressor; 90. Condenser; 100 , vacuum pump.

Detailed ways

The technical solution of the present invention will be described below with reference to the accompanying drawings and examples.

As shown in Figures 1 and 2, the present invention uses an experimental device for extraction and phase equilibrium using pressurized gas that is easily liquefied, including a solvent tank 10, a refrigerator 20, and a high-pressure pump that are connected in an annular manner through pipelines. 30. The balance tank 40 and the separation tank 50, between the solvent tank 10 and the refrigerator 20, between the high-pressure pump 30 and the balance tank 40, between the balance tank 40 and the separation tank 50, and between the separation tank 50 and the solvent tank 10 The balance tank 40 and the separation tank 50 are equipped with water bath jackets. The balance tank includes a tank body 42, a top cover 43 and a barrel 44. The barrel 44 It is detachably inserted into the tank body 42 and is tightly installed in the tank body 42 through the top cover 43; the upper and lower ends of the barrel 44 are respectively provided with an upper end filter plate 444 and a lower end filter plate 447. The area between the upper filter plate 444 and the lower filter plate 447 in the barrel constitutes a solid material extraction area. The upper end of the barrel 44 is located above the upper filter plate 444 and has a liquid distribution hole 446 on the side. The experimental device and method of the present invention can be applied to extraction or phase balance experiments of solid or liquid materials. The device has a simple structure, high experimental efficiency, and high measurement accuracy.

Preferably, a magnetic stirrer 41 is installed at the bottom of the balance tank 40 to stir the solution in the balance tank 40 to increase the dissolution speed and extraction efficiency.

Preferably, a preheating tank 60 is provided between the high-pressure pump 30 and the balancing tank 40. The high-pressure pump 30 and the preheating tank 60 are connected through pipelines and valves. The preheating tank 60 is connected to the balancing tank 60. The tanks 40 are connected through pipelines and valves, so that the temperature of the solution can be increased to a certain extent before entering the balance tank 40, and the extraction efficiency can also be improved. The preheating structure of the preheating tank 60 can also be implemented in the form of a water bath jacket.

Preferably, a buffer tank 70, a compressor 80 and a condenser 90 are connected in sequence between the separation tank 50 and the solvent tank 10. The separation tank 50 and the buffer tank 70 are connected through pipelines and valves. The buffer tank 70 and the compressor 80 are connected through pipelines and valves, the compressor 80 and the condenser 90 are connected through pipelines and valves, and the condenser 90 and the solvent tank 10 are connected through pipelines. It is connected with the valve, so that the separated solvent is compressed and cooled before entering the solvent tank 10, and changes from a gas state to a liquid state, which facilitates the recycling of the solvent.

Preferably, a vacuum pump 100 is also included. The vacuum pump 100 is respectively connected to the balance tank 40, the separation tank 50, the preheating tank 60, the buffer tank 70 and the condenser 90 through pipes and valves. The balance tank is moved between extractions. 40. The separation tank 50, preheating tank 60, buffer tank 70 and condenser 90 are all evacuated, which is beneficial to the flow of the solution and improves the extraction efficiency.

Preferably, a sample collector 53 is detachably installed at the bottom of the separation tank 50 through threaded fit. The sample collector 53 can be selected according to different capacities. According to the experimental conditions, by connecting sample collectors of different lengths, the sample collector 53 can be installed. Changing the sampler capacity to match the actual amount of solute can reduce blank mass and increase metering accuracy.

At the same time, the present invention provides a method for performing extraction and phase equilibrium experiments using pressurized gas that is easily liquefied, including the following steps:

Whether to install the barrel 44 in the balance tank 40 is determined according to the state of the material being extracted. When the material is solid, the barrel 44 is installed in the balance tank 40. When the material is liquid, there is no need to install the barrel 44. into the balance tank 40;

Start the refrigerator 20 and the high-pressure pump 30, so that the solvent in the solvent tank 10 is cooled and then transported to the balance tank 40 through the high-pressure pump 30, and the solute in the balance tank 40 is extracted;

The solution with the solute extracted enters the separation tank 50 for separation of the solvent and the solute. The solute is retained in the separation tank 50 and the solvent is transported to the solvent tank 10 again.

Therefore, the experimental device and method of the present invention can be applied to extraction experiments of solid or liquid materials. The device has a simple structure and high extraction efficiency.

When the solvent enters the balance tank 40 for solute extraction, the magnetic stirrer 41 is started to stir the solution in the balance tank 40 to improve the extraction efficiency.

According to the above solution, before the solvent is transported to the balance tank 40, the solvent is first transported to the preheating tank 60 for preheating, so that the temperature of the solution will be increased before entering the balance tank 40, and the extraction efficiency can also be improved.

According to the above scheme, before entering the solvent tank 10, the solution separated from the separation tank 50 is first buffered by the buffer tank 70, then pressurized by the compressor 80, and finally cooled by the condenser 90 before being transported to the solvent tank 10. The separated solvent is compressed and cooled before entering the solvent tank 10, and changes from a gas state to a liquid state, so that the solvent can be recycled again.

According to the above plan, before starting the refrigerator 20 and the high-pressure pump 30, start the vacuum pump 100 to evacuate the balance tank 40, the separation tank 50, the preheating tank 60, the buffer tank 70 and the condenser 90, which is beneficial to the flow of the solution and improves the extraction. efficiency.

According to the above scheme, before starting the refrigerator 20 and the high-pressure pump 30, a sampler 53 of appropriate capacity is first selected and installed at the bottom of the separation tank. The sampler capacity can be changed by connecting samplers of different lengths according to the experimental conditions. To match the actual amount of solute, it can reduce the blank mass and increase the measurement accuracy.

In the present invention's experimental device and method for extraction and phase equilibrium using pressurized gas that is easily liquefied, a removable barrel 44 is designed inside the balance tank 40, and filter plates are provided at both ends of the barrel 44 so that the barrel can An extraction area is formed between the internal filter plates. When extracting solid materials, the materials can be directly put into the extraction area of the barrel 44, and then the barrel 44 is loaded into the balance tank 40 to perform the extraction process; when extracting liquid materials When performing extraction, the barrel 44 is taken out from the balance tank 40 and the inner space of the tank body 42 of the balance tank 40 is directly used as the extraction zone to extract the material.

The present invention will be described in detail below with reference to a specific embodiment.

As shown in Figure 1, the experimental device of the present invention includes a solvent tank 10, a refrigerator 20, a high-pressure pump 30, a preheating tank 60, a balance tank 40, a separation tank 50, a vacuum pump 100, and a buffer tank 70 that are connected in an annular manner through pipelines. , compressor 80 and condenser 90; the liquid outlet at the bottom of the solvent tank 10 is connected to the liquid inlet of the refrigerator 20, and a valve A is provided to control its connection state; the liquid outlet of the refrigerator 20 It is connected to the liquid inlet of the high-pressure pump 30, and the liquid outlet of the high-pressure pump 30 is connected to the liquid inlet on the upper side of the preheating tank 60, and is provided with a valve B to control its connection state; the outlet at the bottom of the preheating tank 60 The liquid port is connected to the liquid inlet on the upper side of the balance tank 40, and a valve C is provided to control its communication state; the liquid outlet on the lower side of the balance tank 40 is connected to the liquid inlet on the upper side of the separation tank 50, and A valve D is provided to control its connection status. The liquid inlet of the balance tank 40 is also connected to the air outlet on the other side of the upper part of the separation tank 50, and a valve N is provided to control its connection status; the other side of the upper part of the separation tank 50 is also provided. The air outlet is connected to the air inlet on the upper side of the buffer tank 70, and is provided with a valve E to control its connection state; the air outlet on the lower side of the buffer tank 70 is connected to the air inlet of the compressor 80, and is provided with a valve F controls its connection state; the air outlet of the compressor 80 is connected to the air inlet on the left side of the top of the condenser 90, and a valve G is provided to control its connection state; the liquid outlet on the right side of the bottom of the condenser 90 The vent port on the right side of the top of the condenser 90 is connected to the liquid inlet on the upper side of the separation tank 50 and is controlled by a valve J. In its connected state, the vent port on the right side of the top of the condenser 90 is also connected to the atmosphere through a pipeline, and a valve I is provided to control its connected state; the air outlet on the upper side of the separation tank 50 is also connected to the air inlet of the vacuum pump 100 , and is provided with a valve K to control its connection state; the air outlet of the vacuum pump 100 is connected to the air inlet of the buffer tank 70, and a valve L is provided to control its connection state, and the air outlet of the vacuum pump 100 is also connected to the atmosphere through a pipeline. And there is a valve M to control its connection status.

As shown in FIG. 2 , the balance tank specifically includes a tank body 42 , a top cover 43 and a barrel 44 . The tank body 42 is provided with a water bath jacket 45, a liquid inlet pipe 46, and a liquid outlet pipe 47; the lower end of the tank body 42 of the balance tank is closed, and the upper end is open, and a method matching the top cover 43 is provided at the open end. The flange 48, the flange 48 and the top cover 43 have corresponding upper and lower grooves for placing sealing rings. The O-shaped sealing ring 49 can be placed in the groove and tightened with bolts connecting the top cover 43 and the flange 48. and nuts, so that an airtight space is formed inside the balance tank 40; a cylindrical groove is opened in the center of the bottom of the tank 42, so that an annular boss is formed at the bottom close to the side wall of the tank 42, and an annular sealing ring groove is opened on the boss. tank; a magnetic stirrer 411 is placed on the bottom groove of the tank 42, which can be pulled and driven to rotate by the magnetic stirrer 41 under the bottom of the balance tank 40; the water bath jacket 45 is provided with a liquid inlet 451 and a liquid outlet 452, Hot water can be introduced to adjust the temperature in the balance tank 40; a pressure gauge P is provided on the top cover 43 of the balance tank 40 to monitor the pressure in the tank 42, and a thermometer T is provided at the bottom of the balance tank 40 to monitor the pressure in the tank 42. temperature; the barrel 44 can be placed inside the balance tank 40, and a long window is opened on the outer wall of the tank 42, through which the internal conditions of the balance tank 40 can be observed.

As shown in Figure 3, the barrel 44 includes a cylinder body 441, an upper compression screw cap 442 and a lower compression screw cap 443; the upper compression screw cap 442 is a cylindrical structure that penetrates up and down, and has an outer end of the cylinder wall. Threads, and the non-threaded part of the cylinder wall is symmetrically provided with liquid distribution holes 446; the lower pressing screw cap 443 penetrates up and down to form a cylindrical structure, with threads at one end of the outer side of the cylinder wall, and an annular seal at the bottom of the non-threaded end. The barrel 441 is open at the top and bottom, and the insides of the upper and lower openings are provided with threads that fit with the threads of the upper compression screw cap 442 and the lower compression screw cap 443 respectively; the cylinder 441 has two upper and lower openings. An annular shelf is provided at the end of the inner thread of the end, and an annular sealing washer 445, a metal filter plate 444, an annular sealing washer 448, and a metal filter plate 447 are placed on the thread side of the upper and lower shelves in sequence. They are screwed up and down respectively. The compression screw cap 442 and the lower compression screw cap 443 are compacted to form a relatively independent space between the inside of the cylinder 441 and the two metal filter plates 444 and 447, which can only pass through the small openings of the two metal filter plates. Sieve holes communicate with the outside world.

As shown in Figure 4, the barrel 44 can be placed on the bottom boss of the balance tank 40, and the bottom of the barrel 44 presses the annular sealing ring groove on the screw cap 443 and the annular seal of the bottom boss of the balance tank 40. An O-shaped sealing ring is placed between the ring grooves. Under the padding of the O-shaped sealing ring, the upper end plane of the barrel 44 is slightly higher than the plane of the top flange 48 of the balance tank 40, so that the material can be pressed tightly when the top cover 43 is closed. barrel 44, so that the solvent coming in from the liquid inlet pipe 46 can only reach the metal filter plate 444 through the liquid distribution hole 446 of the upper pressing screw cap 442 of the barrel 44, and pass through the filter hole into the inside of the barrel 44, and then pass through the metal filter The plate 447 filters outflow and reaches the liquid outlet pipe 47 .

As shown in Figure 5, the separation tank 50 includes a cylinder 51 and an upper screw cap 52. A sampler 53 is threadedly installed at the bottom of the cylinder 51; the sampler 53 is an elongated tube with a closed bottom end and an open upper end. , there is a thread on the outside of the upper end, and there are multiple sample collectors, which are distinguished by different capacities. According to the experimental conditions, by connecting sample collectors of different lengths, the capacity of the sample collector can be changed to match the actual amount of solute, which can reduce the increase in blank mass. Measurement accuracy; the bottom of the cylinder 51 is tapered, and a threaded port is opened in the center of the bottom to match the threads of the sample adapter 53. A sealing washer 58 is provided between the sample adapter 53 and the threaded port to maintain the sample. The airtightness of the connection between the device 53 and the separation tank 50; a water bath jacket 54 is provided on the outside of the cylinder 51, and a liquid inlet pipe 55 and an air outlet pipe 56 are provided on the upper part of the cylinder 51; the liquid inlet pipe 55 penetrates The back of the cylinder is bent downward at 90 degrees at the center of the cylinder 51 and extends to the tapered mouth at the bottom of the cylinder 51. During the extraction process, the phenomenon of solute sticking to the wall of the separation tank 50 during decompression evaporation can be avoided, ensuring that The solute recovery is complete and the measurement is accurate; the water bath jacket 55 is provided with a liquid inlet 541 and a liquid outlet 542, which can pass in hot water to adjust the temperature in the separation tank 50; the cylinder of the separation tank 50 There is a thread on the inner side of the upper part of 51, and an annular shelf is provided on the lower part of the thread. An annular sealing washer 57 is provided on the shelf. After the upper screw cap 52 is screwed into the thread on the inner side of the cylinder 51, the sealing washer 57 can be pressed to maintain the separation tank 50. The air tightness of the separation tank 50 is provided with a pressure gauge P on the screw cap 52 of the separation tank 50 to monitor the pressure in the tank, and a thermometer T is provided at the bottom of the separation tank 50 to monitor the temperature in the tank 51.

In addition, the high-pressure pump 30 is preferably an HPLC pump, the vacuum pump 100 is preferably a claw-type dry vacuum pump, the compressor 80 is preferably a diaphragm compressor, and the flow meter is preferably a mass flow meter; the preheating tank 60 , the balancing tank 40 and the separation tank 50 are preferably Made of stainless steel, the maximum withstand pressure is 20MPa; the mesh diameter of the metal filter plates 444 and 447 in the barrel 44 is 100-200 mesh; the buffer tank 70 is equipped with stainless steel corrugated or annular fillers, which greatly reduces the work of the vacuum pump The air flow pulsation caused by the mass flow meter allows the air flow to flow smoothly through the mass flow meter to ensure the accuracy of measurement.

When performing the extraction and phase balance experiment of solid materials, the solid material to be tested will be crushed and weighed and then loaded into the barrel 44, and the upper compression screw cap 442 and the lower compression screw cap 443 will be tightened; during the balance Place an O-shaped sealing ring on the sealing ring groove of the bottom boss of the tank 40, and then place the barrel 44 on the bottom boss of the balance tank 40, so that the bottom of the barrel 44 presses the annular sealing ring groove on the screw cap 443. The groove fits on the O-shaped sealing ring; place the O-shaped sealing ring 49 in the sealing ring groove of the flange 48 of the balance tank 40, cover the top cover 43, and tighten the bolts and bolts connecting the top cover 43 and the flange 48. nut to form an airtight space inside the balance tank 40; open valve M, start the vacuum pump, then open valves C, E, J, K and N in sequence, and connect the preheating tank 60, the balance tank 40, the separation tank 50, and the buffer tank 70 and the condenser 90 are evacuated, and then close each valve and the vacuum pump 100 in sequence according to the principle of last opening and first closing; pass circulating water of a certain temperature into the water bath jackets of the preheating tank 60, the balancing tank 40 and the separation tank 50 respectively. Used to regulate the internal temperature of each tank.

Open the valve A of the solvent tank 10 to release the solvent (i.e., pressurized gas that is easily liquefied). The solvent is cooled to a certain temperature by the refrigerator 30, so that the solvent flows into the high-pressure pump 30 in a completely liquid state, and is pressurized and transported to the preheating tank 60. After the solvent temperature and pressure are adjusted to the preset temperature and pressure, valve C is opened to send the solvent into the balance tank 40 through the liquid inlet pipe 46. The solvent flows in through the liquid distribution hole 446 on the upper screw cap 442. , passes through the metal filter plate 444 and enters the internal extraction area of the barrel 44 to contact the material, and then passes through the metal filter plate 447 and flows out of the balance tank 40 through the liquid outlet pipe 47 .

Open valve D to allow the solvent carrying the solute to flow into the separation tank 50. At the same time, open valves E, F, G, and H and start the compressor 80. The solvent evaporates under reduced pressure in the separation tank 50, and the solvent enters from the liquid inlet pipe 55 of the separation tank 50. , is evaporated at the end of the liquid inlet pipe 55, and the solute precipitates out and is collected by the sample adapter 53; after the solvent is vaporized, it is buffered by the buffer tank 70 and flows smoothly into the mass flow meter G. After measuring the mass, it enters the compressor 80 and is compressed and flows through Condenser 90, condenses and liquefies and returns to the solvent tank 10; after the experiment is completed, the sample collector 53 is removed and weighed, and the collected solute mass is obtained based on the mass difference before and after.

When performing a two-phase equilibrium experiment of liquid materials, first take out the barrel 44 from the balance tank 40, and then put the liquid material into the tank body 42 of the balance tank 40. The sealing ring of the flange 48 of the balance tank 40 Place the O-ring seal 49 in the groove, cover the top cover 43, and tighten the bolts and nuts connected to the top cover 43 and the flange 48 to form an airtight space inside the balance tank 40; open the valve M, start the vacuum pump, and then Open valves C, E, J, K and N in sequence, evacuate the preheating tank 60, balance tank 40, separation tank 50, buffer tank 70 and condenser 90, and then close each valve and The vacuum pump 100 introduces circulating water of a certain temperature into the water bath jackets of the preheating tank 60, the balancing tank 40 and the separation tank 50 respectively to adjust the internal temperature of each tank.

Open the valve A of the solvent tank 10 to release the solvent (gas that is easily liquefied under pressure). The solvent is cooled to a certain temperature by the refrigerator 20, so that the solvent flows into the high-pressure pump 30 in a completely liquid state, and is pressurized and transported to the preheating tank 60. After maintaining for a certain period of time and adjusting the solvent temperature and pressure to the preset temperature and pressure, open valve C and send the solvent into the balance tank 40 through the liquid inlet pipe 46. The two-phase equilibrium situation can be observed and photographed through the long window. The experiment is over. Afterwards, the solvent is slowly discharged from the balance tank 40 through the liquid outlet pipe 47.

Open valve D to allow the solvent carrying the solute to flow into the separation tank 50. At the same time, open valves E, F, G, and H and start the compressor 80. The solvent evaporates under reduced pressure in the separation tank 50, and the solvent enters from the liquid inlet pipe 55 of the separation tank 50. , is evaporated at the end of the liquid inlet pipe 55, and the solute precipitates out and is collected by the sample adapter 53; after the solvent is vaporized, it slowly flows into the mass flow meter G through the buffer tank 50, and after measuring the mass, enters the compressor 80, and is compressed and flows through Condenser 90, condenses and liquefies and returns to the solvent tank 10; after the experiment is completed, the sample collector 53 is removed and weighed, and the collected solute mass is obtained based on the mass difference before and after.

Whether in the extraction of solid materials or in the two-phase equilibrium experiment of liquid materials, static or dynamic experiments can be used. When performing a static phase equilibrium experiment, the solvent needs to be sent into the equilibrium tank 40 through the high-pressure pump 30 to reach a predetermined amount, and then the pumping is stopped. At this time, the magnetic stirrer 41 is turned on to perform the static phase equilibrium experiment. After the equilibrium time is reached, the pumping is stopped. Stir and let stand for a period of time, then put the lower solvent into the separation tank 50 for recovery and measurement. According to the weighed material mass, the measured solvent mass and the collected solute mass, the solute in the solvent can be easily calculated. solubility. When performing a dynamic phase equilibrium experiment, the solvent needs to be sent to the balance tank 40 through the high-pressure pump 30, and the pumping flow rate of the high-pressure pump 30 is adjusted to a preset value so that the amount of solvent entering and exiting the balance tank 40 is stable and the two-phase interface height is maintained. The solvent remains unchanged and the solvent is recovered at the same time. The experiment is stopped after the predetermined time is reached. Based on the weighed material mass, the measured solvent mass, and the collected solute mass, the solubility of the solute in the solvent can be easily calculated.

The above are only preferred embodiments of the present invention. Therefore, any equivalent changes or modifications based on the structures, features and principles described in the patent application scope of the present invention are included in the patent application scope of the present invention.

Claims (8)

1. The experimental device for carrying out extraction and phase balance by utilizing pressurized and easily-liquefied gas comprises a solvent tank, a refrigerator, a high-pressure pump, a balance tank and a separation tank which are connected in an annular mode sequentially through pipelines, wherein valves for controlling the on-off of the pipelines are arranged between the solvent tank and the refrigerator, between the high-pressure pump and the balance tank, between the balance tank and the separation tank and between the separation tank and the solvent tank, and water bath jackets are arranged on the balance tank and the separation tank; the upper end and the lower end of the charging barrel are respectively provided with an upper end filter plate and a lower end filter plate, a solid material extraction area is formed in the charging barrel in the area between the upper end filter plate and the lower end filter plate, and liquid distribution holes are formed in the side face of the upper end of the charging barrel, which is positioned above the upper end filter plate;

a preheating tank is further arranged between the high-pressure pump and the balancing tank, the high-pressure pump is connected with the preheating tank through a pipeline and a valve, and the preheating tank is connected with the balancing tank through a pipeline and a valve; the bottom of the separation tank is detachably provided with a sample collector through threaded fit.

2. The experimental device for extraction and phase equilibrium by using pressurized and easily liquefied gas according to claim 1, wherein a buffer tank, a compressor and a condenser are sequentially connected between the separation tank and the solvent tank, the separation tank is connected with the buffer tank through a pipeline and a valve, the buffer tank is connected with the compressor through a pipeline and a valve, the compressor is connected with the condenser through a pipeline and a valve, and the condenser is connected with the solvent tank through a pipeline and a valve.

3. The apparatus according to claim 2, further comprising a vacuum pump connected to the balance tank, the separation tank, the preheating tank, the buffer tank and the condenser through pipes and valves, respectively.

4. A method for carrying out extraction and phase equilibrium experiments by using pressurized and easily liquefied gas, characterized in that the experimental device according to any one of claims 1-3 is used, and specifically comprises the following steps:

determining whether to install the material cylinder in the balance tank according to the state of the extracted material, and installing the material cylinder into the balance tank when the material is solid, and not installing the material cylinder into the balance tank when the material is liquid;

starting a refrigerator and a high-pressure pump, so that the solvent in the solvent tank is refrigerated and then is conveyed into the balance tank through the high-pressure pump, and the solute in the balance tank is extracted;

the solution from which the solute is extracted enters a separation tank for solvent and solute separation, the solute remains in the separation tank, and the solvent is transported to the solution tank again.

5. The method of claim 4, wherein the solvent is preheated in a preheating tank before the solvent is fed to the balancing tank.

6. The method for extraction and phase equilibrium experiments using a pressurized, easily liquified gas of claim 5, wherein the solution separated from the separator is buffered in a buffer tank, pressurized in a compressor, cooled in a condenser and then transferred to the solvent tank before entering the solvent tank.

7. The method of claim 6, wherein the pre-heating tank, the balancing tank, the separation tank, the buffer tank and the condenser are evacuated by starting the vacuum pump before starting the refrigerator and the high pressure pump.

8. The method of claim 4, wherein the sample collector is mounted to the bottom of the separation tank prior to starting the refrigerator and the high pressure pump.