JPS58124197A - Heat-accumulating material - Google Patents

Abstract

PURPOSE:To obtain a heat-accumulating material having stable heat-absorbing and heat-releasing performances and a high heat-accumulating capacity, by a method wherein sodium acetate, urea, glycine and water are used to produce a heat-accumulating mateial, and the composition of the materials is changed to regulate heat-accumulating and heat-releasing temperatures thereof. CONSTITUTION:The heat-accumulating material is comprised of 20-70wt% of sodium acetate (NaCH3COO) not more than 65wt% of urea[CO(NH2)2]not more than 30wt% of glycine (MH2CH2COOH) and 15-50wt% of water (H2O). When the amount of NH2CH2COOH is increased against the amount of the eutectic composition of NaCH3COO.3H2O and CO(NH2)2, the transition point of the material is lowered, and also the latent heat of transition is slightly reduced. When the amount of CO(NH2)2 is increased against the amount of the eutectic composition of NaCH3COO.3H2O and NH2CH2COOH, the transition point of the material is lowered, and also the latent heat of transition tends to be slightly reduced. Accordingly, the heat-accumulating and heat-releasing temperatures can be regulated by changing the composition of the material, and the heat-accumulating material having stable heat-absorbing and heat-releasing performances and a high heat-accumulating capacity can be obtained.

Description

[Detailed description of the invention] The present invention is sodium acetate (NaCH3CO0).

Urea (Co(MHz)2), Clidine (an2aH2c
ooon) and water.

In general, there are two types of heat storage materials: those that utilize the sensible heat of substances and those that utilize latent heat. Heat storage materials that use latent heat have a larger amount of heat storage per unit weight or unit volume than heat storage materials that use sensible heat, and require only a small amount of heat storage material to store the required amount of heat. Therefore, it is possible to downsize the heat storage device. In addition, a heat storage material that uses latent heat has the characteristic that it radiates heat at a constant temperature at a transition point, without causing the temperature to drop as heat is radiated, unlike a heat storage material that uses sensible heat. In particular, heat storage materials that utilize the latent heat of fusion of inorganic hydrates are known to have a large amount of heat storage per unit volume.

By the way, conventionally NaCH3000-3H20 (melting point 6
8.2 G) is known to be a substance with a particularly large latent heat of fusion among inorganic hydrates. However, NaCH
3COo・3H20 has a high melting point of 58.2 G, so
It has been difficult to widely apply it to heat storage devices that utilize solar heat. Therefore, methods have been proposed to lower the melting point of N, CH3COO, 3H20 by adding various types of false acid salts and other inorganic salts. The latent heat decreases,
Practical implementation was difficult.

The present invention uses NaCH3COO, Co(MHz)2.

The present invention provides a heat storage material that can control heat storage and heat radiation temperatures by changing the composition of a system consisting of NH2CH2COOH and H2O, is inexpensive, has stable heat absorption and radiation performance, and has a large amount of heat storage. ,
NaCH3Coo, Co(N112)2.

It consists of four components: NH2CH2COOH and N20, and preferably NaCH3COO is 20% by weight (
Co
(NF2)2 is in the range of 65% or less, NF2 CH
2C0OH is in the range of 30% or less, N20 is 16%
A range of 50% or less is preferable.

Examples will be described below.

Commercially available reagent special grade NaCH3Coo, NaCH3Go
O-3H20, GO(NF2)2. NH2CH2CO
N20 purified by ion exchange after distillation with OH,
The mixture was blended as shown in Tables 1 to 4, heated to 65°G to dissolve as much solid matter as possible, and used as a sample.

The magnitude of latent heat and transition temperature of these samples were determined using a differential scanning calorimeter (p, s, c). As the transition temperature, the endothermic peak temperature of the DSC curve when the sample melts was used. The measurement results are shown in Tables 5 to 8.

By the way, what is shown in Table 1 is NaCH3CO53H
N which is a eutectic composition of 20 and CO(NF2)2
aCH3coo 38%, co(NF2)2 37%
.

This is a sample with a system containing 26% N20 and a composition with NH2CH2COOH as both end components, and Table 2 shows that NaCH3
61.3% NaCH3COO, which is a eutectic composition of COO・3H2o and NH2OH2000H.

This sample has a composition of yarn containing 16% NH2CH2C00H and 33.7% N20, and GO(NF2)2 as both end components.

Also, Table 3 shows samples having compositions around those in Tables 1 and 2, where the ratio of N, 0M3Coo and N20 was kept constant so that the stoichiometric composition was N21CH3Coo-3H20. It is something that is hanging down. Table 4 shows samples with compositions around those in Tables 1 to 3. In this case, keeping the content of NH2CH2COOH constant,
Go (NF2)2. NaCH3co.

and N20 by changing the ratio.

In Tables 6 to 8, if each sample undergoes transition at two or more temperatures, those temperatures are listed. Furthermore, as a matter of course, the transition below 00C was considered unnecessary in this case, so it was not considered a problem.

In addition, the evaluations shown in Tables 5 to 8 show that the latent heat is 3 oct)/y
The above samples were marked O, samples with a latent heat of 2ocIL1/g or more and less than 3ocal/g were marked Δ, and the others were marked ×. Those marked with ○ have a large amount of heat storage and can be put to practical use, and those marked with △ have a not so large amount of heat storage, but the transition temperature is in a temperature range not found in conventional latent heat storage materials, so they can be put into practical use. This is considered to be the case.

(Leaving space below) Analyze the data in Table 1, Table 2, Table 4, Table 5, Table 6, Table 7, Table 8, and Table 5. The sample in this table is NaCH3
N with a eutectic composition of Coo・3H20 and Go(Nl2)2, 38% CH3COO, Go(Nl2)
A system containing 37% of 2 and 26% of H2O and NH2CH2
This is a composition containing COOH as both end components.

if, Sample 1 containing 0.2% NH2CH2COOH
Then, the transition point is 31. The latent heat at O'C is 49 cal/&
It's big. Therefore, as the content of Nl2CH2C0OH is increased, the transition point gradually decreases, and the latent heat also decreases, albeit slightly.

For samples with NH2CH2COOH content of 2% or more,
A different transition from the transition around 300C occurs around 26°C. As the content of NH2CH2COOH increases, the transition temperature on the high temperature side decreases, and the transition temperature on the low temperature side remains at approximately 26°C.

In samples containing 8% or more of NH2CH2C00H, the transition on the low temperature side is observed to overlap with the transition on the high temperature side. So, like samples 7 and 8.9, NH2CH2C00H
It can be seen that the composition containing 8 to 12% of has a transition around 26°C and has a latent heat of +ocal/, 9 or more, making it a large latent heat storage material.

By the way, - these samples are Co(NHz)2 and NaC
Eutectic composition of H3COO・3H20 and N H20H2C
Considering that it has a composition with OOH as both end components, the transition at 25@C is N a CH3COO・5
H20.

Co(NHz)2. This is thought to be due to the eutectic of the three components NH2CH2C00H.

Analyze the characteristics in Table 6 in the same manner as in Table 6. The samples in this table are NaCjH3Coo ・3H20 and NHZ CH2
61. NaOH3Coo having a eutectic composition of C0G1.
3%.

NHZ CH200011 16%, H2O 33.7
% and CO(NHz)2 as both end components.

First, in sample 11 containing 0.2% GO(NHz)2, the transition temperature is 47.30, and the latent heat at that time is 61
cIL1/g, which is large. Therefore, as the content of GO(NHz)2 increases, the transition temperature gradually decreases,
Along with this, the latent heat also decreases, albeit slightly. CO(
In samples containing 2% or more of NHz)2, a different transition occurs around 26°C than around 458C. As the content of GO(NHz)2 increases, the transition temperature on the high temperature side decreases.

The transition temperature on the low temperature side remains unchanged at approximately 26°C. In a sample containing 30% or more of CO(NHz)2, the transition on the mold temperature side is observed to overlap with the transition on the high temperature side.

Therefore, like samples 17, 18, and 19, Go(NHz
) A sample containing 30 to 40% of 2 has a transition around 26° C. and has a large latent heat of *ocal/g or more, and has extremely desirable characteristics as a latent heat storage material. This 2
The transition at 6°C is the same as in Table 4. L C
H3CO0・3H20G O(NH2) 2 .

This is thought to be due to the eutectic three-component system of NH2OH2(:OOH.In other words, the samples in Table 4 are NaCH
Eutectic composition of 3COO・3H20 and co(NHz)2 [
Na by adding NH2111jH2COOH
CH3Coo-3H20, Co (NHz)2. N.H.
While the three-component eutectic composition of 2OH2COOH was reached, Table 6 shows Teha, NaCH3COO-3H20 and N
By adding CO(NHz)2 to the eutectic composition of H2CH2COOH, NaCH3Coo-3H20,NH
2OH2COOH.

A three-component eutectic composition consisting of CO(NHz)2 has been achieved. This three-component eutectic composition is
aCH3COO-3H20 is considered to contain 57% CO(NHz)2 at 33% and NH2OH2C0OH at 10%. This eutectic composition naturally has Na
CH3COO 34.4%, Co(NHz)2 33%
%, NH2CH2C00H 10%, H2O 22.6
%.

From this, for the samples shown in Table 1.

NILCH3Coo ・3H20 and C0 (NHz)z
By adding NH2CH2COOH to the eutectic system, it is possible to control the melting point between 31°G and 26°C, and the latent heat at that time is greater than aoaal/g, making it an extremely excellent heat storage material that has never existed before. I can see that it is. Also, in the samples shown in Table 2.

N a OH3CO0・3 H20 and NHz CH2c
By further adding CO(NHz)2 to the oono eutectic fj, it is possible to control the melting point between 48°C and 26°C, and the latent heat at that time is also 3o
It can be seen that cILVg...7- or more, making it an extremely excellent heat storage material that has never existed before.

Next, the composition of the sample in Table 7 is in the i22@ region around the compositions shown in Tables 1 and 2, and the ratio of N, CH3COO and H2O is kept constant so as to have a constant pressure composition of NaCH3COO-3H20. This is what was held. In this case, N
aCH3Coo-5H20, Co(NHz)2.

It is best to think of it as a three-component system of NH2CH2C00H, Na OH3Coo ・3H20 Go
The eutectic composition of (NHz)2 is a composition containing 37% of CO(NHz)2, and NaCH3COO-sH20 and NH
The eutectic composition of 2OH2COOH is NHz ca2 coo
Le composition containing 15% of H, N & CH3CO
0.3 H20 (!: G O (NH2) 2t NH
zCH2CooH 3-component eutectic composition co (NHz)
The composition contains s s% of 2 and 10% of NHz CH2C0OH, and the eutectic temperature of each is 31 ° C9
Considering that the temperatures are 48°C and 26°C, the characteristics of each sample shown in this table can be understood.

Sample 22 CO(NHz)2 at 6%, )fH2CH2
COOH 6%, )ilcH3cOo-sH20woeo
%(NaCH3(joo54,3%, H2O35,7%
) When the sample containing NaCH3 is cooled from the molten state, the NaCH3
COO.3H20 begins to precipitate, and its amount increases as the temperature decreases. Then, when cooled to about 43°C, the solution composition becomes NaCH3Coo・3H20 and NH2
Eutectic composition of CH2COOH and NaCH3COO・3H
20 and NH2CH2COOH, and CO(Nl2)2
It is thought that it lies on the line connecting the three-component eutectic compositions. From this point on, it can be considered that the samples are the same as those shown in Table 2. In other words, N a CH3CO0・3H20 and NH
While precipitating 2CH2COOH, the solution composition approaches a ternary eutectic composition. The remaining solution of this three-component eutectic composition becomes solid by solidification.

In this way, sample 22 is able to dissipate heat while precipitating crystals in stages between 64°G and 25°G, and has an extremely large latent heat of 62 cal/g, making it an extremely excellent product that has never existed before. It serves as a heat storage material. As described above, Samples 21 to 39 shown in Table 3 have a size sufficient to serve as a heat material at several stages, depending on their respective compositions.

Analyze the properties of the samples in Table 8. In this case, NH2
The content of CH2C00H was kept constant at 1%, and the content of NaOH3
CooO, GO('NH2)2. The composition of H2O is changed. Samples 41 to 49 are NH2CH2C
The content of 0O is 1% and the content of Co(Nl2)2 is 9%.
, the ratio of Na CH3COO and H2O was changed. What can be learned from the characteristics of these samples is that
The ratio of N & CH3COO to H2O is NaCH3COO
・When forming 3H20 17) Sample 46, which is closest to 60 to 4°, has the largest latent heat, and N, lCH3CO
Sample 44 on the H20 rich side from the electric ratio composition of 0-sH20,
As it moves to 43.42, the latent heat decreases and the transition temperature also decreases. Also, compared to the electrical specific composition of Na CH3000.3 H2O, N! The latent heat decreases as the samples 46, 47, 48, and 49 move toward the L Ci H3COO excess side. However, in this case, the transition temperature hardly changes.

Such a relationship was also observed in samples 50 to 67, in which the content of Nl2Cl2COOH was held constant at 1% and the content of Co(Nl2)2 was held constant at 39%, while the ratio of NaOH3Coo and H2O was varied. Sample 64, whose ratio of NaCH3COO to H2O is closest to the composition of NaCH3COO-3H20, has the largest latent heat.

That is, Co(Nl2)2. When the content of NH2OH2C00H is kept constant, %NaCH3Coo and H
When the ratio of 2O is NaCH3Coo ・3H20, the latent heat is the largest, and from this electric ratio H2O
Even if the composition shifts to the excess side or the composition shifts to the NaCH3COO side, the latent heat decreases. Also, the transition temperature is NaCH3C
The ratio of OO to H2O (7) decreases significantly on the H20 overly rich side compared to NaCH3COO-3H20, and Na Cj H3
On the 000-profit side, there is little change or a slight increase.

To summarize the above results, the composition regions of the samples marked with △ and ○ in Tables 5 to 8, that is.

NaCH3COO, Go(Nl2)2. NH2OH2C
OOH.

In the four-component system of H2O, NaCH3COO is 20%
The range is 7o% or less, and CO(Nl2)2 is 0%.
larger, in the range of 66% or less, NH2CH2C
It is preferable that OOH is 0%, 11) large and 30% or less, and H2O is in the range of 16% or more and 50% or less.

Next, NaCH3 (joo to 34.2%, Go(
NIL4P2 was added as a supercooling prevention material to 800g of a mixture having the same composition as sample 8 containing 33.3% Nl2)2, 10% NH2OH2Cool, and 22.6% H2O.
20 g of 07.1oH20 was added, and the container was placed in a cylindrical container with an inner diameter of 1 oomm and a height of 10071'Lm, and the container was sealed with a thermocouple-inserted bone stopper. Then, heat this container to 10°C and 4o'
When repeatedly heated and cooled at 1C, the heat storage material of the present invention did not exhibit any supercooling and repeatedly melted and solidified in a stable manner. W: It was confirmed that it had heat absorption and radiation performance.

As described above, the present invention is directed to NaCHaCoo.

CO(Nl2)2. 4 of NH2CH2C00H1H20
The object of the present invention is to provide a heat storage material which is composed of components, whose heat storage and heat radiation temperatures can be controlled by changing their composition, is inexpensive, has stable heat absorption and radiation performance, and has a large amount of heat storage. In addition, in the present invention, a melting point depressant may be used in combination, a supercooling prevention material may be used, a thickening agent may be used to prevent the supercooling prevention material from settling or agglomerating, and other additives may be used. Of course, you may add as appropriate.

As described above, the heat storage material of the present invention can be applied not only to heat storage devices for air conditioning for cooling and heating purposes, but also to all fields that utilize heat storage.

Name of agent: Patent attorney Masao Nakao, and one other person Procedural amendment dated 1980, 10th son, 29th year, Director General of the Patent Office, 1. Display of case, 1986 Patent application No. 7061, 2. Name of invention, heat storage material, 3. Person making the amendment. Relationship to incident Patent application
Address: 1006 Kadoma, Kadoma City, Osaka Prefecture
Name (582) Matsushita Electric Industrial Co., Ltd. Representative Toshihiko Yamashita 4 Agent 571 Address Matsushita Electric Industrial Co., Ltd., 1006 Oaza Kadoma, Kadoma City, Osaka ~1-□ 6. Contents of amendment (1) Specification In page 4, line 20, replace ``each'' with ``as the transition temperature, indicate the peak temperature of the DSC curve, and''
will be corrected.

(2) Tables 6 and 6 on pages 1o to 13 of the same book.

Tables 7 and 8 will be amended as shown in the attached sheets.

(3) "49" in line 7 of page 14 of the same oath is corrected to "64".

(4) "61" on page 16, line 16 of the same book has been corrected to "66".

(6) “62” in the same book, page 19, line 17, is changed to “57”
will be corrected.

Table 6 Table 6 Table 7 Table 8

Claims (2)

[Claims] (1) A heat storage material comprising sodium acetate, urea, glycine, and water. (2) 20 to 70% by weight of sodium acetate, 65% of urea
% by weight or less, glycine is 30% by weight or less, water is 16~
The heat storage material according to claim 1, which has a content of 60% by weight.