Ethanolamine phase change material
By using molecular sieve to remove moisture and adding a cooling agent to adjust its phase transition temperature, the problem of difficulty in crystallization of ethanolamine is solved, and the reduction of phase transition temperature and the improvement of application value is achieved.
Patent Information
- Application Number
- CN202411502492.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-25
- Publication Date
- 2025-02-07
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
When ethanolamine contains 1% water, it needs to crystallize at -5°C, resulting in limited application.
The problem of crystallization difficulty is solved by using molecular sieve to remove moisture from ethanolamine and adding a cooling agent to adjust the phase change temperature, so as to reduce the phase change temperature to 6°C.
The phase transition temperature of ethanolamine is adjusted and reduced to 6℃, solving the problem of crystallization difficulties and improving its application value.
Smart Images
Figure CN119391378A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of phase change materials, and in particular to an ethanolamine phase change material. Background Art
[0002] Phase change material refers to a material that changes its state and provides latent heat while the temperature remains unchanged. The process of changing physical properties is called phase change. At this time, the phase change material will absorb or release a large amount of latent heat. The phase change material has the ability to change its physical state within a certain temperature range. Phase change is the process of a substance changing from one phase to another. The uniform part with exactly the same physical and chemical properties as other parts in the material system and a clear interface is called a phase. Corresponding to the three states of solid, liquid and gas, a substance has solid phase, liquid phase and gas phase. When a phase change occurs, there is a change in volume and heat absorption or release at the same time. This type of phase change is called a "first-order phase change". For example, at 1 atmosphere and 0°C, 1 kg of ice turns into water at the same temperature, absorbing 79.6 kcal of heat, and at the same time the volume shrinks. Therefore, the conversion between ice and water is a first-order phase transition. When the phase change occurs, the volume does not change, and there is no absorption or release of heat. Only the physical quantities such as heat capacity, thermal expansion coefficient and isothermal compression coefficient change. This type of change is called a second-order phase transition. The transition between normal liquid helium (helium I) and superfluid helium (helium II), the transition between normal conductors and superconductors, the transition between paramagnets and ferromagnets, and the transition between the ordered and disordered states of alloys are all typical examples of second-order phase transitions.
[0003] At present, the melting point of ethanolamine is 10.5°C, and it has the characteristics of high phase change enthalpy, low cost and high flash point. It is a potential high-performance phase change material. In addition, the phase change temperature can be adjusted by adding a small amount of water. However, water makes it difficult for ethanolamine to crystallize, and the supercooling degree can reach more than 10°C. Studies have found that when ethanolamine contains 1% water, it needs to be at -5°C to crystallize, thus limiting its practical application. Summary of the invention
[0004] In view of the melting point of the above-mentioned existing ethanolamines being 10.5°C, and having the characteristics of high phase change enthalpy, low cost and high flash point, they are potential high-performance phase change materials. In addition, the phase change temperature can be adjusted by adding a small amount of water. However, water causes difficulty in crystallization of ethanolamine, and the supercooling degree can reach more than 10°C. Moreover, studies have found that when ethanolamine contains 1% water, it needs to be crystallized at -5°C. Therefore, the problem of limiting its practical application leads to the present invention.
[0005] Therefore, the purpose of the present invention is to provide an ethanolamine phase change material, which aims to remove moisture from ethanolamine by molecular sieves and adjust the relative temperature by cooling agents so that the phase change temperature can be reduced to 6°C. The phase change temperature can be adjusted, and therefore, it has a high application value.
[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: an ethanolamine phase change material, comprising the following components:
[0007] 90-98 parts of anhydrous ethanolamine;
[0008] 2-10 parts of cooling agent.
[0009] As a preferred embodiment of the ethanolamine phase change material of the present invention, the anhydrous ethanolamine is prepared by adding 10 parts of fresh molecular sieves (3A, 4A, 5A) to 100 parts of commercially available ethanolamine (water content <2%) to obtain anhydrous ethanolamine with a water content <0.05%.
[0010] As a preferred embodiment of the ethanolamine phase change material of the present invention, the cooling agent is one or more of sodium hydroxide, potassium hydroxide, calcium chloride, sodium nitrate and potassium nitrate.
[0011] To achieve the above object, the present invention provides the following technical solution: a method for preparing an ethanolamine phase change material, comprising the following steps:
[0012] S1, first add 10 parts of fresh molecular sieves (3A, 4A, 5A) to 100 parts of commercially available ethanolamine (water content <2%) and then let stand for 6-24 hours;
[0013] S2, then the raw material in S1 is tested by Karl Fischer method to obtain anhydrous ethanolamine with a water content of <0.05%;
[0014] S3, adding a cooling agent to the anhydrous ethanolamine with a water content of less than 0.05% obtained in S2 to adjust its phase change temperature, thereby obtaining an ethanolamine phase change material.
[0015] The beneficial effects of the present invention are as follows: the moisture in ethanolamine is removed by using a molecular sieve, and the phase change temperature is adjusted by using a cooling agent, so that the phase change temperature can be reduced to 6°C. The phase change temperature can be adjusted, and the problem that ethanolamine needs to be crystallized at -5°C when it contains 1% moisture is solved. Therefore, the present invention has a high application value. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:
[0017] Figure 1 It is a schematic diagram of the DSC test results of Example 1 of the ethanolamine phase change material of the present invention.
[0018] Figure 2 It is a schematic diagram of the DSC test results of Example 3 of the ethanolamine phase change material of the present invention. DETAILED DESCRIPTION
[0019] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.
[0020] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.
[0021] Example 1
[0022] Reference Figure 1-2 , which is the first embodiment of the present invention, provides an ethanolamine phase change material, and the ethanolamine phase change material includes the following components:
[0023] 98 parts of anhydrous ethanolamine;
[0024] 2 parts cooling agent.
[0025] The anhydrous ethanolamine is prepared by adding 10 parts of fresh molecular sieves (3A, 4A, 5A) to 100 parts of commercially available ethanolamine (water content <2%) to obtain anhydrous ethanolamine with a water content <0.05%.
[0026] The cooling agent is potassium hydroxide.
[0027] A method for preparing an ethanolamine phase change material comprises the following steps:
[0028] S1, first add 10 parts of fresh molecular sieves (3A, 4A, 5A) to 100 parts of commercially available ethanolamine (water content <2%) and then let stand for 6-24 hours;
[0029] S2, then the raw material in S1 is tested by Karl Fischer method to obtain anhydrous ethanolamine with a water content of <0.05%;
[0030] S3, adding a cooling agent to the anhydrous ethanolamine with a water content of less than 0.05% obtained in S2 to adjust its phase change temperature, thereby obtaining an ethanolamine phase change material.
[0031] DSC test results of the prepared phase change material Figure 1 .
[0032] Example 2
[0033] Reference Figure 1-2, which is the second embodiment of the present invention, and which is different from the first embodiment in that:
[0034] 95 parts of anhydrous ethanolamine;
[0035] 5 parts of cooling agent.
[0036] The anhydrous ethanolamine is prepared by adding 10 parts of fresh molecular sieves (3A, 4A, 5A) to 100 parts of commercially available ethanolamine (water content <2%) to obtain anhydrous ethanolamine with a water content <0.05%.
[0037] The cooling agent is 3 parts of calcium chloride and 2 parts of sodium nitrate.
[0038] The remaining structures are the same as those of Example 1.
[0039] Example 3
[0040] Reference Figure 1-2 , which is the third embodiment of the present invention, and which is different from the second embodiment in that it includes the following components:
[0041] 90 parts of anhydrous ethanolamine;
[0042] 10 parts of cooling agent.
[0043] The anhydrous ethanolamine is prepared by adding 10 parts of fresh molecular sieves (3A, 4A, 5A) to 100 parts of commercially available ethanolamine (water content <2%) to obtain anhydrous ethanolamine with a water content <0.05%.
[0044] The cooling agent is sodium hydroxide.
[0045] DSC test results of the prepared phase change material Figure 2 .
[0046] The remaining structure is the same as that of Example 2.
[0047] Example 4
[0048] Reference Figure 1-2 , which is the fourth embodiment of the present invention, and which is different from the third embodiment in that it includes the following components:
[0049] Anhydrous ethanolamine 93 parts;
[0050] 7 parts of cooling agent.
[0051] The anhydrous ethanolamine is prepared by adding 10 parts of fresh molecular sieves (3A, 4A, 5A) to 100 parts of commercially available ethanolamine (water content <2%) to obtain anhydrous ethanolamine with a water content <0.05%.
[0052] The cooling agent is 3 parts of sodium hydroxide and 4 parts of potassium nitrate.
[0053] The remaining structure is the same as that of Example 3.
[0054] Comparative Example 1
[0055] This embodiment is different from the fourth embodiment in that it includes the following components:
[0056] 98 parts of anhydrous ethanolamine;
[0057] Cooling agent 0 parts;
[0058] 2 parts water.
[0059] The anhydrous ethanolamine is prepared by adding 10 parts of fresh molecular sieves (3A, 4A, 5A) to 100 parts of commercially available ethanolamine (water content <2%) to obtain anhydrous ethanolamine with a water content <0.05%.
[0060] The remaining structures are the same as those of Example 4.
[0061] Comparative Example 2
[0062] This embodiment is different from Comparative Example 1 in that it includes the following components:
[0063] 100 parts of anhydrous ethanolamine;
[0064] Cooling agent 0 parts;
[0065] 0 parts water.
[0066] The anhydrous ethanolamine is prepared by adding 10 parts of fresh molecular sieves (3A, 4A, 5A) to 100 parts of commercially available ethanolamine (water content <2%) to obtain anhydrous ethanolamine with a water content <0.05%.
[0067] The rest of the structure is the same as that of Comparative Example 1.
[0068] The results of the embodiments can be found in the following table:
[0069]
[0070]
[0071] By using molecular sieves to remove moisture from ethanolamine and using a cooling agent to adjust the phase temperature, the phase change temperature can be reduced to 6°C. The phase change temperature can be adjusted, solving the problem that ethanolamine needs to be crystallized at -5°C when it contains 1% moisture. Therefore, it has high application value.
[0072] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.
Claims
1. An ethanolamine phase change material, characterized in that: The components include: 90-98 parts of anhydrous ethanolamine; 2-10 parts of cooling agent.
2. The ethanolamine phase change material according to claim 1, characterized in that: The anhydrous ethanolamine is prepared by adding 10 parts of fresh molecular sieves (3A, 4A, 5A) to 100 parts of commercially available ethanolamine (water content <2%) to obtain anhydrous ethanolamine with a water content <0.05%.
3. The ethanolamine phase change material according to claim 2, characterized in that: The cooling agent is one or more of sodium hydroxide, potassium hydroxide, calcium chloride, sodium nitrate and potassium nitrate.
4. A method for preparing an ethanolamine phase change material, which is applied to the ethanolamine phase change material described in claim 3, characterized in that: The following steps are included: S1, first add 10 parts of fresh molecular sieves (3A, 4A, 5A) to 100 parts of commercially available ethanolamine (water content <2%) and then let stand for 6-24 hours; S2, then the raw material in S1 is tested by Karl Fischer method to obtain anhydrous ethanolamine with a water content of <0.05%; S3, adding a cooling agent to the anhydrous ethanolamine with a water content of less than 0.05% obtained in S2 to adjust its phase change temperature, thereby obtaining an ethanolamine phase change material.