CN111826126B

CN111826126B - Phase change material for low-temperature cold accumulation at-77 to-88 ℃ and preparation method thereof

Info

Publication number: CN111826126B
Application number: CN201910326481.8A
Authority: CN
Inventors: 史全; 柴思瑀
Original assignee: Dalian Institute of Chemical Physics of CAS
Current assignee: Dalian Institute of Chemical Physics of CAS
Priority date: 2019-04-23
Filing date: 2019-04-23
Publication date: 2022-03-08
Anticipated expiration: 2039-04-23
Also published as: CN111826126A

Abstract

The invention discloses a low-temperature cold accumulation phase-change material and a preparation method thereof. The method synthesizes the cold accumulation phase change material by mixing two or three of ketones, aldehydes and alkanes. The low-temperature phase-change material synthesized by the method has the advantages of high phase-change latent heat, good thermal stability and low preparation cost, and is easy to be applied to cold accumulation.

Description

Phase change material for low-temperature cold accumulation at-77 to-88 ℃ and preparation method thereof

Technical Field

The invention relates to the field of phase change energy storage, in particular to a low-temperature cold accumulation phase change material and a preparation method thereof.

Background

With the development of industry, the living standard is improved, so that the world faces the problem of energy crisis. In the aspect of electric energy, particularly in summer, due to the fact that the requirements of people for life are increasingly improved, the difference of electricity consumption in daytime and at night is large due to the use of various electric appliances such as air conditioners and refrigerators, the peak-valley load difference is large, and the load rate of a power grid is reduced. At present, the country encourages to develop low-ebb electricity utilization and can realize 'peak shifting and valley filling'. Meanwhile, with the enhancement of crisis awareness of people, the development of new energy becomes a research hotspot at present. The cold accumulation technology can adjust energy supply and demand, save operation cost and realize high-efficiency and reasonable utilization of energy. The phase change cold storage material can be used as a carrier for storing energy, stores the energy in the low valley of the power load, slowly releases the energy in the peak of the power load, and the like, and has important significance in the aspect of energy conservation.

The cold accumulation technology is a high and new technology for regulating and controlling the environmental temperature by storing sensible heat, latent heat or reaction heat in chemical reaction at high density in the process of changing the state of a working medium. The method has important application value and wide development prospect in the fields of peak-valley balance of electric power, energy conservation and refrigeration transportation of air conditioners, low-temperature storage of substances and the like. For example, the annual power consumption of a 5000-ton refrigerator is about 800 million kilowatt hours, and the total amount of the refrigerator in China reaches 800 million tons; in the aspect of low-temperature logistics, due to different temperature requirements of transported goods, different cold storage technologies need to be researched according to the suitable temperature of the goods.

And nowadays, with the development of scientific technology, the environment required by research can be more accurate, and many experiments need to maintain a specific temperature during the experiment to maintain the reaction to continue, or the temperature environment of the experiment needs to be kept unchanged in order to recycle the sample and to store the sample after the experiment.

The phase change cold storage material is widely applied to various industries, and when a sample needs to be maintained in an ultralow temperature space, most of researches are at a medium-low temperature, and few researches on the phase change material at the ultralow temperature are available. The inorganic phase-change material has serious supercooling phenomenon and phase separation phenomenon, and the stability and the cyclicity are all to be improved. The organic phase-change material has the advantages of no corrosion, no supercooling, no phase separation, stable thermal performance and the like.

Disclosure of Invention

Based on the defects of the background technology, the invention aims to provide the low-temperature cold accumulation phase-change material which has the temperature of-77 to-88 ℃, does not corrode, does not have supercooling, does not have the phase separation phenomenon and has stable thermal performance.

The synthesis of the low-temperature cold accumulation phase-change material comprises the following steps:

(1) mixing ketone, aldehyde and alkane in certain proportion to obtain mixed solution.

(2) The mixture is strictly sealed and stirred at normal temperature for a period of time to be uniformly mixed, and the low-temperature cold accumulation phase-change material is obtained.

Further, the mixing proportion of the prepared low-temperature cold accumulation phase-change material is ketone: aldehydes: 67-85% of alkane and 0-18% of alkane: 0 to 16%.

Furthermore, the ketones adopted by the prepared low-temperature cold accumulation phase change material are one or more of 3-pentanone, 2-pentanone, heptanone and butanone.

Furthermore, the aldehyde adopted by the prepared low-temperature cold accumulation phase change material is one or more of propionaldehyde, butyraldehyde and heptaldehyde.

Furthermore, the alkane adopted by the prepared low-temperature cold accumulation phase change material is one or more of octane, nonane, decane and heptane.

Further, the stirring time for preparing the low-temperature cold accumulation phase change material is 30-60 min.

Further, the rotating speed of the prepared low-temperature cold accumulation phase-change material is 300-400 r/min.

Furthermore, the melting point of the prepared low-temperature cold accumulation phase-change material is-77 to-88 ℃.

The reagents involved in the invention are simple and easy to obtain, the operation requirement of preparation is low, and the prepared low-temperature cold accumulation phase-change material is transparent liquid and has the advantages of high phase-change performance, good cycle stability and the like. The product can be applied to the aspects of liquefied natural gas cold energy storage, environmental constant temperature keeping in the experimental process, medicine transportation and the like.

Drawings

FIG. 1 is a DSC curve of the product of example 1.

Detailed Description

Example 1

(1) The heptanone, heptaldehyde and decane were mixed in a molar ratio of 78:12: 10.

(2) And stirring for 30min at normal temperature after strict packaging at 400r/min to obtain a uniform mixed solution, namely the low-temperature cold accumulation phase change material, and the material can still keep good phase change latent heat and temperature phase change performance after 500-30-120 ℃ temperature rise and fall reciprocating thermal cycles.

Example 2

(1) 3-pentanone, octane and decane were mixed in a molar ratio of 88.7:10: 1.3.

(2) And then strictly packaging the materials, and stirring the materials at the normal temperature for 60min at 300r/min to obtain a uniform mixed solution, namely the low-temperature cold accumulation phase change material is prepared.

Example 3

(1) Pentanone and nonane are mixed in a molar ratio of 85: 15.

(2) And then strictly packaging, and stirring at the normal temperature for 45min at 350r/min to obtain a uniform mixed solution, namely preparing the low-temperature cold accumulation phase change material.

Example 4

(1) Hexanone, heptanal and octane are mixed according to a molar ratio of 82:8: 10.

(2) And after strict packaging, stirring at the normal temperature at 350r/min for 30min to obtain a uniform mixed solution, thus obtaining the low-temperature cold accumulation phase change material.

Example 5

(1) Mixing 2-pentanone, propionaldehyde and decane according to a molar ratio of 79:15: 6.

(2) And after strict packaging, stirring at normal temperature at 400r/min for 30min to obtain a uniform mixed solution, thus obtaining the low-temperature cold accumulation phase change material.

Example 6

(1) Mixing butanone, heptaldehyde and nonane according to a molar ratio of 72:13: 15.

Example 7

(1) Hexanone and octane were mixed in a molar ratio of 85: 15.

(2) And after strict packaging, stirring at normal temperature for 30min at 300r/min to obtain a uniform mixed solution, thus obtaining the low-temperature cold accumulation phase change material.

Example 8

(1) 3-pentanone, propionaldehyde and nonane are mixed according to a molar ratio of 67:18: 15.

Example 9

(1) Hexanone, heptane and octane were mixed in a molar ratio of 68:16: 16.

Example 10

(1) 3-pentanone, heptanal and butyraldehyde are mixed according to a molar ratio of 84:7: 9.

Comparative example 1

(1) Heptanone, propionaldehyde and octane were mixed in a molar ratio of 90:5: 5.

(2) And then strictly packaging and stirring at the normal temperature for 30min at 300r/min to obtain a uniform mixed solution, thus obtaining the low-temperature cold accumulation phase change material.

Comparative example 2

(1) Butanone, heptaldehyde and decane were mixed in a molar ratio of 60:25: 15.

(2) And then strictly packaging and stirring at the normal temperature at 350r/min for 30min to obtain a uniform mixed solution, thus obtaining the low-temperature cold accumulation phase change material.

Comparative example 3

(1) 3-pentanone, nonane and octane were mixed in a molar ratio of 30:10: 60.

(2) And then strictly packaging the materials, and stirring the materials at the normal temperature for 30min at 400r/min to obtain a uniform mixed solution, namely the low-temperature cold accumulation phase change material is prepared.

Comparative example 4

(1) Heptanone, propionaldehyde and butane were mixed in a molar ratio of 50:25: 25.

Comparative example 5

(1) Butanone, heptaldehyde and octane were mixed in a molar ratio of 35:12: 53.

Table 1 properties of low-temperature phase change cold storage materials obtained in examples 1 to 3

Claims

1. A low-temperature cold accumulation phase-change material is characterized in that: is prepared by mixing ketones, aldehydes and one or more than two of alkanes;

the ketones are one or more of 3-pentanone, 2-pentanone, heptanone and butanone; ketones in the phase change material: aldehydes: the molar ratio of alkane to hydrocarbon is 67-85% to 0-18%: 0 to 16 percent; the molar ratio of one or more than two of aldehydes and alkanes in the phase-change material is more than or equal to 15 percent; the aldehyde is one or more of propionaldehyde, butyraldehyde and heptaldehyde;

the alkane is one or more of octane, nonane and decane.

2. The cryogenic cold storage phase change material according to claim 1, characterized in that: esters in phase change materials: alcohols: the molar ratio of alkane is 78-79 percent to 11-12 percent to 9-10 percent.

3. The cryogenic cold-storage phase-change material according to claim 1 or 2, characterized in that: the melting point of the organic low-temperature phase change material is-77 to-88 ℃.

4. A method for preparing the low-temperature cold-storage phase-change material as claimed in claim 1, wherein the method comprises the following steps: the method comprises the following steps:

1) mixing ketones, aldehydes and one or two substances in alkanes according to a proportion to obtain a mixed solution; the ketone is one or more of 3-pentanone, 2-pentanone, heptanone and butanone; the molar mixing ratio is ketone: aldehydes: 67-85% of alkane and 0-18% of alkane: 0 to 16 percent;

2) sealing the mixed solution at normal temperature, stirring to mix uniformly to obtain the low-temperature cold accumulation phase change material

And (5) feeding.

5. The preparation method of the low-temperature cold-storage phase-change material according to claim 4, characterized in that: the aldehydes in the step (1) are one or more of propionaldehyde, butyraldehyde and heptaldehyde;

in the step (1), the alkane is one or more of octane, nonane and decane.

6. The preparation method of the low-temperature cold-storage phase-change material according to claim 4, characterized in that: what is needed is

The stirring time in the step (2) is 30-60 min.

7. The preparation method of the low-temperature cold-storage phase-change material according to claim 4, characterized in that: the rotating speed in the step (2) is 300-400 r/min.

8. Use of the cryogenic cold-storage phase change material according to any of claims 1-3 for energy storage at cryogenic conditions.

9. Use of a cryogenic cold storage phase change material according to claim 8, characterized in that: the product can be applied to the processes of keeping the environment at constant temperature, transporting medicines or storing cold energy of liquefied natural gas and the like in experiments.