Thermogravimetric analysis equipment

Abstract

The invention relates to the technical field of thermogravimetric analysis equipment, particularly provides thermogravimetric analysis equipment, and aims to solve the problem that a high-temperature and high-pressure measurement environment is difficult to realize at the same time due to the fact that the mechanical strength of a stainless steel shell, used for bearing pressure, of an existing thermogravimetric analysis instrument is reduced at a high temperature, and then the pressure bearing capacity of the stainless steel shell is reduced. In order to achieve the purpose, the thermogravimetric analysis equipment comprises a sample chamber, the sample chamber comprises a shell and a heating piece used for heating a sample, the heating piece is installed in the shell, and a heat insulation layer used for blocking heat transfer between the heating piece and the shell is arranged between the shell and the heating piece. When the thermogravimetric analysis equipment is used, most of heat generated by the heating sheet can be blocked by the heat insulation layer in the process of transferring the heat to the shell, so that the temperature of the shell is reduced, the shell can keep good pressure bearing capacity, and the thermogravimetric analysis equipment can be suitable for a high-temperature and high-pressure environment.

Description

Technical Field

[0001] The invention relates to the technical field of thermogravimetric analysis equipment, and specifically provides a thermogravimetric analysis equipment. Background Art

[0002] Thermogravimetric analysis (TGA) is a technique for measuring the change in sample mass under temperature control. It is used to measure the change in mass of a material under heating conditions. The relevant instrument is called a thermogravimetric analyzer, which is widely used in materials science, chemistry, pharmaceuticals, food and other industries. It usually consists of a heating furnace, a sample crucible, a precision balance, a temperature control system and a data acquisition system. Traditional thermogravimetric analyzers usually perform analysis at normal pressure or low pressure, which is suitable for thermal decomposition and reaction studies of most materials. However, for some special materials or reaction systems, such as high-pressure catalytic reactions, gas adsorption and desorption, thermal decomposition of materials under supercritical fluid conditions, etc., the pressure conditions of conventional thermogravimetric analyzers limit their scope of application, so high-pressure thermogravimetric analyzers (high-pressure TGA) came into being.

[0003] Compared with traditional TGA, high-pressure TGA has two major improvements: high-pressure vessels and magnetic levitation technology. The introduction of high-pressure vessels provides a pressure- and temperature-controllable environment for samples. Since the high-pressure vessel is a closed environment, the traditional method of mechanically connecting the sample and the balance sensor through a connecting rod is no longer applicable. Magnetic levitation technology was introduced, and the balance and the sample were "connected" through the outer wall of the high-pressure vessel, allowing the balance to weigh the sample without physically contacting the sample crucible. However, the mechanical strength of the stainless steel shell used to bear pressure in the existing high-pressure TGA will decrease at high temperatures, thereby reducing its pressure-bearing capacity, which ultimately makes it difficult to simultaneously achieve a high-temperature and high-pressure measurement environment, severely limiting the scope of application of the equipment.

[0004] In view of this, a new thermogravimetric analysis device is needed in the art to solve the existing problems. Summary of the invention

[0005] The present invention aims to solve the above technical problem, that is, to solve the problem that the mechanical strength of the pressure-bearing stainless steel shell of the existing thermogravimetric analyzer decreases at high temperatures, thereby reducing its pressure-bearing capacity, and ultimately making it difficult to simultaneously achieve a high temperature and high pressure measurement environment.

[0006] In a first aspect, the present invention provides a thermogravimetric analysis device, comprising a sample chamber, wherein the sample chamber comprises a shell and a heating plate for heating a sample, wherein the heating plate is installed inside the shell, and an insulating layer is provided between the shell and the heating plate for blocking heat transfer between the heating plate and the shell.

[0007] In a specific embodiment of the above-mentioned thermogravimetric analysis equipment, the thermal insulation layer includes a first thermal insulation part and a second thermal insulation part, the top of the first thermal insulation part is provided with a mounting protrusion, and the bottom of the second thermal insulation part is provided with a mounting groove, and the mounting protrusion can be embedded in the mounting groove to realize the installation of the first thermal insulation part and the second thermal insulation part.

[0008] In a specific embodiment of the above-mentioned thermogravimetric analysis equipment, through holes are provided in the middle areas of the first thermal insulation part and the second thermal insulation part, the first thermal insulation part and the second thermal insulation part are sleeved on the outside of the heating plate and embedded between the heating plate and the inner wall of the shell, and the thermal insulation layer is made of ceramic fiber material.

[0009] In a specific embodiment of the above-mentioned thermogravimetric analysis device, a cooling structure is arranged on the shell, and the cooling structure includes a cooling channel arranged in the shell, and the two ends of the cooling channel are respectively connected to the liquid inlet and the liquid outlet, and the coolant can flow in the cooling channel through the liquid inlet and the liquid outlet.

[0010] In a specific embodiment of the above-mentioned thermogravimetric analysis device, the cooling structure includes a first cooling chamber arranged between the outer wall and the inner wall of the shell, a first liquid inlet connected to the lower part of the first cooling chamber, and a first liquid outlet connected to the upper part of the first cooling chamber, a first cooling channel is arranged in the first cooling chamber, the first cooling channel surrounds the inner wall and / or the outer wall of the shell, and multiple layers are arranged along the direction from the first liquid inlet to the first liquid outlet, and gaps are opened between the first cooling channels of adjacent layers so that the coolant can flow between the first cooling channels of different layers.

[0011] In a specific embodiment of the above-mentioned thermogravimetric analysis device, the cooling structure also includes a second cooling cavity arranged at the top of the shell and a second liquid inlet and a second liquid outlet communicated with the second cooling cavity, a second cooling channel is arranged in the second cooling cavity, the second cooling cavity and the second cooling channel are both annular, and along the radial direction of the second cooling cavity, the second cooling channel is arranged in multiple layers, and gaps are opened between the second cooling channels of adjacent layers so that the coolant can flow between the second cooling channels of different layers, the second liquid inlet is communicated with the second cooling channel of the innermost / outermost layer, and the second liquid outlet is communicated with the second cooling channel of the outermost / innermost layer.

[0012] In a specific embodiment of the above-mentioned thermogravimetric analysis equipment, a sample crucible and an isolation tube are also provided in the sample chamber, the sample crucible is used to place the sample, the isolation tube is arranged on the outside of the sample crucible and the isolation tube is sealed to maintain the airtightness of the internal space of the isolation tube, a seal is arranged between the isolation tube and the inner wall of the shell, and an inert gas equal to the air pressure in the isolation tube is filled, and the isolation tube is made of ceramic material.

[0013] In a specific embodiment of the above-mentioned thermogravimetric analysis device, the heating plate is in a spiral climbing shape and surrounds the outside of the isolation tube to heat the sample in the sample crucible, and the heating plate is made of silicon carbide.

[0014] In a specific embodiment of the above-mentioned thermogravimetric analysis equipment, the thermogravimetric analysis equipment also includes a thermocouple temperature sensor for obtaining the sample temperature, the tip of the thermocouple temperature sensor is a ceramic sleeve, the end is a metal sleeve, and part of the metal sleeve is sleeved on the ceramic sleeve, and the connection between the metal sleeve and the ceramic sleeve is filled with copper oxide for sealing.

[0015] In a specific embodiment of the above-mentioned thermogravimetric analysis equipment, the thermogravimetric analysis equipment also includes a microbalance, the microbalance includes a first weighing part and a second weighing part, the first weighing part is arranged above the second weighing part, the first weighing part includes a dial indicator and a first magnetic device, the first magnetic device is an electromagnetic force device, and the first magnetic device is connected to the dial indicator of the microbalance, the second weighing part includes a second magnetic device, the second magnetic device is a permanent magnet and is connected to the sample in the sample chamber, and the magnetic force generated by the first magnetic device after power is turned on can attract the second magnetic device and the sample and weigh them through the dial indicator.

[0016] The technical effect of the present invention is as follows: during the use of the thermogravimetric analysis device of the present invention, since a heat insulation layer is provided between the shell and the heating plate, in the process of heat generated by the heating plate when heating the sample being transferred toward the shell, most of the heat will be blocked by the heat insulation layer, thereby avoiding a large amount of heat being transferred to the shell and causing the temperature of the shell to be too high, and solving the problem that the mechanical strength of the pressure-bearing stainless steel shell of the existing thermogravimetric analyzer will decrease at high temperature, thereby reducing its pressure-bearing capacity, and ultimately making it difficult to simultaneously achieve a high temperature and high pressure measurement environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings, in which:

[0018] Figure 1 It is a schematic diagram of the overall structure of the thermogravimetric analyzer of the present invention;

[0019] Figure 2 is a half-section view of a thermogravimetric analyzer of the present invention, wherein Figure 2 yes Figure 1 BB in the middle;

[0020] Figure 3 It is a schematic structural diagram of a sample chamber of a thermogravimetric analyzer of the present invention;

[0021] Figure 4 is a half-section view of a sample chamber of a thermogravimetric analyzer of the present invention, wherein Figure 4 yes Figure 3 AA in the middle;

[0022] Figure 5 is a schematic diagram of the sample chamber of the thermogravimetric analyzer of the present invention with the right side housing removed;

[0023] Figure 6 is a front structural schematic diagram of the second cooling chamber of the present invention;

[0024] Figure 7 is a schematic diagram of the back structure of the second cooling chamber of the present invention;

[0025] Figure 8 is a schematic structural diagram of a first heat insulation portion;

[0026] Fig. 9 is a schematic structural diagram of the second heat insulation part;

[0027] Fig.10 It is a schematic diagram of the structure of the heating plate;

[0028] Fig.11 It is a structural diagram of a thermocouple temperature sensor.

[0029] List of reference numerals:

[0030] 1-thermogravimetric analyzer; 11-sample chamber; 111-housing; 12-first cooling chamber; 121-first liquid inlet; 122-first liquid outlet; 123-first cooling channel; 13-second cooling chamber; 131-second liquid inlet; 132-second liquid outlet; 133-second cooling channel; 134-flow guide channel; 14-sample crucible; 15-isolating tube; 16-heating plate; 17-insulating layer; 171-first insulating part; 1711-installing protrusion; 172-second insulating part; 1721-installing groove; 18-thermocouple temperature sensor; 180-metal ferrule; 181-ceramic sleeve; 182-metal sleeve; 183-copper oxide; 19-microbalance; 191-indicator; 192-first magnetic device; 193-second magnetic device. DETAILED DESCRIPTION

[0031] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention. Those skilled in the art can make adjustments to them as needed to adapt to specific application scenarios.

[0032] It should be noted that in the description of the present invention, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0033] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] First, the existing high-pressure thermogravimetric analyzer is described. The sample chamber of the existing high-pressure thermogravimetric analyzer is a closed chamber, which can provide a pressure- and temperature-controlled environment for the sample. However, since the mechanical strength of stainless steel decreases at high temperatures, the pressure-bearing capacity of the pressure-bearing shell of the existing high-pressure thermogravimetric analyzer decreases, so that the thermogravimetric analyzer cannot meet the measurement requirements under high temperature and high pressure environments, which seriously limits the scope of application of the equipment. For this reason, the following implementation method is proposed.

[0035] Embodiment 1

[0036] like Figure 1-Figure 10As shown, in order to solve the problem that the mechanical strength of the stainless steel shell 111 used for bearing pressure of the existing thermogravimetric analyzer 1 will decrease at high temperature, thereby reducing its pressure bearing capacity, and finally making it difficult to simultaneously achieve a high temperature and high pressure measurement environment, the thermogravimetric analyzer 1 of the present invention includes a sample chamber 11, and the sample chamber 11 includes a shell 111 and a heating plate 16 for heating the sample, the heating plate 16 is installed in the shell 111, and a heat insulation layer 17 is arranged between the shell 111 and the heating plate 16, the heat insulation layer 17 includes a first heat insulation part 171 and a second heat insulation part 172, the top of the first heat insulation part 171 is provided with a mounting protrusion 1711, and the bottom of the second heat insulation part 172 is provided with a mounting groove 1721, and the mounting protrusion 1711 can be embedded in the mounting groove 1721 to achieve a sealed installation of the first heat insulation part 171 and the second heat insulation part 172. A through hole is opened in the middle area of ​​the first insulation part 171 and the second insulation part 172. The first insulation part 171 and the second insulation part 172 are sleeved on the outside of the heating plate 16 and embedded between the heating plate 16 and the inner wall of the shell 111. The insulation layer 17 is made of ceramic fiber.

[0037] The advantages of the above embodiment are: since the ceramic material has the characteristics of high temperature resistance and low thermal conductivity, in this embodiment, by setting a ceramic material insulation layer 17 between the heating plate 16 and the inner wall of the shell 111, the heat leakage of the heating plate 16 to the shell 111 can be well limited. On the one hand, the heat preservation of the heating end is achieved, and the heating efficiency of the heating plate 16 is improved. On the other hand, the temperature of the shell 111 is reduced, so that the thermogravimetric analyzer 1 of the present invention can be tested under high temperature and high pressure environment, solving the existing problems. In addition, by setting the insulation layer 17 as a detachable first insulation part 171 and a second insulation part 172, the installation and removal of the insulation layer 17 are facilitated. At the same time, since the installation protrusion 1711 and the installation groove 1721 are set at the connection between the first insulation part 171 and the second insulation part 172, after the first insulation part 171 and the second insulation part 172 are installed, compared with the plane contact, the installation protrusion 1711 and the installation groove 1721 avoid direct convection of gas, thereby effectively reducing the temperature leakage at the joint.

[0038] Embodiment 2

[0039] The above has introduced the heat insulation layer 17 between the heating plate 16 and the housing 111. Next, the related structures on the housing 111 will be introduced. Figure 1-Figure 7As shown, a cooling structure is provided on the shell 111, and the cooling structure includes a cooling channel provided in the shell 111, and the two ends of the cooling channel are respectively connected to the liquid inlet and the liquid outlet, and the coolant can flow in the cooling channel through the liquid inlet and the liquid outlet. Specifically, the cooling structure includes a first cooling cavity 12 provided between the outer wall and the inner wall of the shell 111, a first liquid inlet 121 connected to the lower part of the first cooling cavity 12, and a first liquid outlet 122 connected to the upper part of the first cooling cavity 12. Following the shape of the sample chamber 11 shell 111, in this embodiment, the first cooling cavity 12 is annular as a whole, and a plurality of first liquid inlets 121 and first liquid outlets 122 are provided. A first cooling channel 123 is arranged in the annular first cooling cavity 12. The first cooling channel 123 surrounds the inner wall of the shell 111, and is provided with multiple layers along the direction from the first liquid inlet 121 to the first liquid outlet 122 (i.e., from bottom to top). A gap is opened between adjacent layers of the first cooling channels 123, and the coolant can flow from one layer of the first cooling channel 123 to another layer of the first cooling channel 123 through the gap.

[0040] In the case of adopting the above-mentioned embodiment, during the use of the thermogravimetric analyzer 1 of the present invention, driven by a driving component such as a pressure pump, the coolant can flow from the first liquid inlet 121 into the first cooling channel 123 of the lowest layer in the first cooling chamber 12. After filling the first cooling channel 123 of the lowest layer, the coolant overflows into the first cooling channel 123 of the upper layer from the gap on the first cooling channel 123. After filling the first cooling channel 123 of the upper layer, the coolant overflows into the first cooling channel 123 of the upper layer, and then overflows into the first cooling channel 123 of the upper layer, and so on until the first cooling channel 123 in the first cooling chamber 12 is completely filled and the first cooling chamber 12 is finally filled, and then flows out of the first cooling chamber 12 from the first liquid outlet 122. In the process of the coolant flowing through the first cooling chamber 12, the coolant can exchange heat with the shell 111 to increase the temperature while taking away the heat on the shell 111. After the heated coolant is cooled outside the first cooling chamber 12, it re-enters the first cooling chamber 12 to cool the shell 111, and the cycle continues.

[0041] The advantages of the above embodiment are: by setting the first cooling chamber 12 between the outer wall and the inner wall of the shell 111 and cooling the shell 111 by the coolant, the temperature of the shell 111 during the thermogravimetric analysis process is reduced, so that the temperature of the shell 111 can always be kept below 80°C, thereby ensuring the pressure bearing capacity of the stainless steel shell 111, and then the thermogravimetric analyzer 1 of the present invention can be tested under high temperature and high pressure environment, solving the existing problems, and due to the presence of the thermal insulation layer 17, the coolant will not affect the temperature of the actual working area. In addition, by setting the first liquid inlet 121 at the bottom and the first liquid outlet 122 at the top, and setting multiple layers of first cooling channels 123 in the first cooling chamber 12 and diffusing them layer by layer, the flow distance of the coolant in the first cooling chamber 12 is increased, thereby extending the heat exchange time between the coolant and the shell 111, and improving the heat exchange efficiency. In addition, setting multiple first liquid inlets 121 and first liquid outlets 122 improves the liquid inlet and outlet efficiency of the first cooling chamber 12. Regarding the location of the first cooling channel 123, those skilled in the art will understand that the first cooling channel 123 can also be surrounded on the outer wall of the shell 111, or can be surrounded on both the outer wall and the inner wall of the shell 111 to form a staggered first cooling channel 123. These changes do not exceed the technical principles of the present invention, and therefore will also be included in the protection scope of the present invention. In addition, regarding the cooling channel, those skilled in the art will understand that the cooling channel is not limited to the aforementioned form, but can also be a cooling channel formed directly inside the shell 111 by casting or other commonly used production processes, that is, the cooling structure can also be in the form of not including a cooling cavity, but only including a cooling channel. These changes are all within the protection scope of the present invention.

[0042] Embodiment 3

[0043] like Figure 1-Figure 7 As shown, the cooling chamber also includes a second cooling chamber 13 located at the top of the shell 111, a second liquid inlet 132 and a second liquid outlet communicated with the second cooling chamber 13, a second cooling channel 133 is arranged in the second cooling chamber 13, the second cooling channel 133 and the second cooling chamber 13 are both annular, and along the radial direction of the second cooling chamber 13 (i.e., from the outside to the inside or from the inside to the outside), the second cooling channel 133 is arranged in multiple layers, and gaps are also opened between the second cooling channels 133 of adjacent layers, and a guide channel 134 is also arranged in the second cooling chamber 13, the second liquid inlet 132 is communicated with the innermost layer of the second cooling channel 133 after passing through the guide channel 134, and the second liquid outlet is communicated with the outermost layer of the second cooling channel 133.

[0044] Since the shell 111 of the sample chamber 11 is made of stainless steel, heat will inevitably be transferred to the top of the shell 111, and a precision weighing device such as a microbalance 19 is arranged on the top of the shell 111. In order to reduce the influence of temperature on weighing, a second cooling chamber 13 is also arranged on the top of the shell 111 in this embodiment. In the case of adopting the above embodiment, driven by a driving component such as a pressure pump, the coolant can enter the second cooling chamber 13 from the second liquid inlet 132, and flow into the innermost second cooling channel 133 along the guide channel 134 connected to the second liquid inlet 132. After the innermost second cooling channel 133 is filled, it flows into the second cooling channel 133 of the outer layer through the gap, and after the second cooling channel 133 of the outer layer is filled, it flows into the second cooling channel 133 of the outer layer, and so on until all the second cooling channels 133 are filled, and the coolant flows out from the second liquid outlet. In this process, the coolant fully exchanges heat with the top of the shell 111 and takes away the heat from the top of the shell 111, thereby achieving the purpose of lowering the temperature of the top of the shell 111. While ensuring the operation of precision weighing equipment such as the microbalance 19, the overall temperature of the shell 111 is also lowered, avoiding the situation where the temperature at the top of the shell 111 is high and the temperature at the side of the shell 111 is low, and heat conduction occurs on the shell 111, reducing the cooling efficiency of the cooling structure on the side of the shell 111. In addition, regarding the second liquid inlet 132 and the second liquid outlet, those skilled in the art can also connect the second liquid inlet 132 with the outermost second cooling channel 133 and connect the second liquid outlet with the innermost second cooling channel 133. These changes do not exceed the technical principles of the present invention, and therefore will also be included in the protection scope of the present invention.

[0045] Embodiment 4:

[0046] In the above-mentioned embodiment, the scheme of the present invention is introduced from the perspective of cooling the shell 111. In addition, the present invention has also made improvements on the heating end. Specifically, a sample crucible 14 and an isolation tube 15 are further provided in the sample chamber 11. The sample crucible 14 is used to place the sample. The isolation tube 15 is arranged on the outside of the sample crucible 14 and the isolation tube 15 is sealed to maintain the airtightness of the internal space of the isolation tube 15. An inert gas is filled between the isolation tube 15 and the inner wall of the shell 111, and the air pressure is equal to that in the isolation tube 15. The heating plate 16 is spirally climbing and surrounds the outside of the isolation tube 15. The heating plate 16 is used to heat the sample in the sample crucible 14. The heating plate 16 is made of silicon carbide and the isolation tube 15 is made of ceramic.

[0047] The advantage of the above embodiment is that in the prior art, the heating plate 16 is not arranged around the outside of the isolation tube 15, but is arranged side by side next to the isolation tube 15. In this way, of the heat released by the heating plate 16, only the heat toward the side of the isolation tube 15 can heat the isolation tube 15 and the sample inside it, while the heat away from the side of the isolation tube 15 is dissipated into the shell 111, which not only has low heating efficiency for the sample, but also increases the temperature of the shell 111, further reducing the bearing capacity of the shell 111 under high temperature conditions. In this embodiment, by surrounding the heating plate 16 on the outside of the isolation tube 15, the heat generated by the heating plate 16 is concentrated to heat the sample, thereby improving the heating efficiency of the sample, reducing the energy consumption of the heating plate 16, and while more heat is applied to the sample, only less heat is dissipated into the shell 111, thereby avoiding a serious increase in the temperature of the shell 111. In addition, in some cases, the sample may be tested in a corrosive environment. By sealing the ceramic isolation tube 15, the corrosive gas inside the isolation tube 15 is prevented from escaping and contacting the shell 111, thereby reducing the need for the corrosion resistance of the stainless steel shell 111. At the same time, since an inert protective gas is filled between the isolation tube 15 and the inner wall of the shell 111 and the air pressure inside and outside the isolation tube 15 is equal, the isolation tube 15 is almost not subjected to air pressure difference and can maintain good structural stability at high temperatures. Although the stainless steel shell 111 is indirectly in contact with the high temperature, it is protected and cooled by the inert gas and can maintain sufficient mechanical strength. At the same time, the heating plate 16 is also protected by the inert gas. In addition, the silicon carbide material can still maintain excellent mechanical properties at high temperatures, has a low thermal expansion coefficient, and has high hardness and corrosion resistance. As a heating plate 16, it has excellent physical and chemical properties.

[0048] Embodiment 5

[0049] Thermogravimetric analyzer 1 usually includes a temperature sensor for obtaining sample temperature. The commonly used temperature sensor is a thermocouple temperature sensor 18. The outer shell of thermocouple temperature sensor 18 is usually made of stainless steel. When thermocouple temperature sensor 18 measures sample temperature, in order to ensure the airtightness inside isolation tube 15, it is usually necessary to use metal ferrule 180 to clamp and seal thermocouple temperature sensor 18. When metal ferrule 180 is sealed, thermocouple temperature sensor 18 needs to be clamped so that the stainless steel outer shell of thermocouple temperature sensor 18 is squeezed and deformed. However, when the temperature exceeds 1400°C, most commonly used high-temperature alloys including stainless steel cannot maintain the necessary mechanical properties. For this reason, this embodiment is proposed. Figure 4 , Figure 5 , Fig.11As shown, in this embodiment, the tip of the thermocouple temperature sensor 18 is a ceramic sleeve 181, the end is a metal sleeve 182 (for example, stainless steel), and part of the metal sleeve 182 is sleeved on the ceramic sleeve 181, and the connection between the metal sleeve 182 and the ceramic sleeve 181 is filled with copper oxide 183 for sealing.

[0050] In the case of adopting the above embodiment, since the tip of the thermocouple temperature sensor 18 is set to be a ceramic material and the end is set to be a stainless steel material, when in use, the stainless steel sleeve is placed in the metal ferrule 180 for clamping and sealing, and the ceramic sleeve 181 is placed in the isolation tube 15 for measuring the temperature of the sample. The advantage of this embodiment is that by setting the tip and the end of the thermocouple temperature sensor 18 to ceramic and stainless steel materials respectively according to the requirements of high temperature resistance and high strength, the temperature measurement of the sample under high temperature and high pressure environment is achieved. In addition, since copper oxide 183 is resistant to high temperature, corrosion-resistant and easy to process, copper oxide 183 is used as a filler at the connection between the metal sleeve 182 and the ceramic sleeve 181 for sealing.

[0051] It is mentioned in the above embodiment that when the heating end is working, heat will inevitably be transferred to the microbalance 19, and the temperature change will affect the reading of the microbalance 19, a precision instrument. As time goes by, the reading error caused by this temperature drift will become more and more obvious. The weighing structure of the existing microbalance 19 is located below the sample, with a complex structure and high installation accuracy requirements, and the sensitivity is usually 0.1μg. The long-term temperature drift error is particularly obvious when the sensitivity is as high as 0.1μg, which cannot be ignored and is very difficult to correct. For this reason, if Figure 1 , Figure 2 As shown, in a possible embodiment, the thermogravimetric analysis equipment also includes a microbalance 19, the microbalance 19 includes a first weighing part and a second weighing part, the first weighing part is arranged above the second weighing part, the first weighing part includes an indicator 191 and a first magnetic device 192, the first magnetic device 192 is an electromagnetic force device, and the first magnetic device 192 is connected to the indicator 191 of the microbalance 19, the second weighing part includes a second magnetic device 193, the second magnetic device 193 is a permanent magnet and is connected to the sample in the sample chamber 11, the magnetic force generated by the first magnetic device 192 after being energized can suck up the second magnetic device 193 and the sample and weigh them through the indicator 191, the sensitivity of the microbalance 19 is 10μg, and the range is 50g.

[0052] The advantages of the above embodiment are: by setting the microbalance 19 to include a first weighing part and a second weighing part, and setting the first weighing part above the second weighing part, the first weighing part and the second weighing part are connected by a hanging magnetic suspension, and the sensitivity of the microbalance 19 is reduced to 10μg. On the one hand, since the form structure of the hanging magnetic suspension connection is relatively simple, the installation accuracy requirement is low, and since the sensitivity of the microbalance 19 is reduced to 10μg, the allowable range of the microbalance 19 is increased to 50g, so overall, measured by the percentage of weight change, the accuracy of the weighing part is not significantly lost, and the anti-interference ability of the microbalance 19 with the hanging magnetic suspension connection in this embodiment is relatively strong. On the other hand, the microbalance 19 with the hanging magnetic suspension connection in this embodiment can also conveniently realize zero point correction during the experiment through the sample decoupling structure, thereby avoiding the influence of temperature drift on the accuracy of weighing to a large extent.

[0053] It should be noted that the above-mentioned implementation mode is only used to illustrate the principle of the present invention and is not intended to limit the scope of protection of the present invention. Without departing from the principle of the present invention, those skilled in the art can adjust the above-mentioned structure so that the present invention can be applied to more specific application scenarios.

[0054] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A thermogravimetric analysis device, characterized in that: The thermogravimetric analysis device comprises a sample chamber, which comprises a shell and a heating plate for heating the sample. The heating plate is installed inside the shell, and an insulating layer is arranged between the shell and the heating plate to block heat transfer between the heating plate and the shell.

2. The thermogravimetric analysis device according to claim 1, characterized in that The thermal insulation layer includes a first thermal insulation part and a second thermal insulation part. The top of the first thermal insulation part is provided with a mounting protrusion, and the bottom of the second thermal insulation part is provided with a mounting groove. The mounting protrusion can be embedded in the mounting groove to realize the installation of the first thermal insulation part and the second thermal insulation part.

3. The thermogravimetric analysis device according to claim 2, characterized in that The middle areas of the first insulation part and the second insulation part are provided with through holes. The first insulation part and the second insulation part are sleeved on the outside of the heating plate and embedded between the heating plate and the inner wall of the shell. The insulation layer is made of ceramic fiber.

4. The thermogravimetric analysis device according to claim 1, characterized in that The shell is provided with a cooling structure, which includes a cooling channel arranged in the shell, and two ends of the cooling channel are respectively connected with a liquid inlet and a liquid outlet, and the coolant can flow in the cooling channel through the liquid inlet and the liquid outlet.

5. The thermogravimetric analysis device according to claim 4, characterized in that The cooling structure includes a first cooling cavity arranged between the outer wall and the inner wall of the shell, a first liquid inlet communicated with the lower part of the first cooling cavity, and a first liquid outlet communicated with the upper part of the first cooling cavity. A first cooling channel is arranged in the first cooling cavity. The first cooling channel surrounds the inner wall and / or the outer wall of the shell, and multiple layers are arranged along the direction from the first liquid inlet to the first liquid outlet. Gaps are opened between the first cooling channels of adjacent layers so that coolant can flow between the first cooling channels of different layers.

6. The thermogravimetric analysis device according to claim 4, characterized in that The cooling structure also includes a second cooling cavity arranged at the top of the shell, and a second liquid inlet and a second liquid outlet communicated with the second cooling cavity, a second cooling channel is arranged in the second cooling cavity, the second cooling cavity and the second cooling channel are both annular, and the second cooling channel is arranged in multiple layers along the radial direction of the second cooling cavity, and gaps are opened between the second cooling channels of adjacent layers so that coolant can flow between the second cooling channels of different layers, the second liquid inlet is communicated with the second cooling channel of the innermost / outermost layer, and the second liquid outlet is communicated with the second cooling channel of the outermost / innermost layer.

7. The thermogravimetric analysis device according to claim 1, characterized in that The sample chamber is also provided with a sample crucible and an isolation tube. The sample crucible is used to place samples. The isolation tube is arranged outside the sample crucible and is sealed to maintain the airtightness of the internal space of the isolation tube. The isolation tube is sealed to the inner wall of the shell and is filled with an inert gas having the same air pressure as that in the isolation tube. The isolation tube is made of ceramic material.

8. The thermogravimetric analysis device according to claim 7, characterized in that The heating plate is in a spiral climbing shape and surrounds the outside of the isolation tube to heat the sample in the sample crucible. The heating plate is made of silicon carbide.

9. The thermogravimetric analysis device according to claim 1, characterized in that: The thermogravimetric analysis equipment also includes a thermocouple temperature sensor for obtaining the sample temperature. The tip of the thermocouple temperature sensor is a ceramic sleeve and the end is a metal sleeve. Part of the metal sleeve is sleeved on the ceramic sleeve. The connection between the metal sleeve and the ceramic sleeve is filled with copper oxide for sealing.

10. The thermogravimetric analysis device according to claim 1, characterized in that: The thermogravimetric analysis equipment also includes a microbalance, which includes a first weighing part and a second weighing part. The first weighing part is arranged above the second weighing part. The first weighing part includes a dial indicator and a first magnetic device. The first magnetic device is an electromagnetic device, and the first magnetic device is connected to the dial indicator of the microbalance. The second weighing part includes a second magnetic device, which is a permanent magnet and is connected to the sample in the sample chamber. The magnetic force generated by the first magnetic device after power is turned on can attract the second magnetic device and the sample and weigh them through the dial indicator.

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