JP2017002212A - Latent heat storage material composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a latent heat storage material composition for heating which is a coordination type and requires effect of heat storing and radiating with conducting heat absorbing and radiation of latent heat at a temperature setting in a range of transition point of 40°C to 50°C by a suspension of a blend effectively affecting on heat resistance and ion exchange capacity of cation, anion or the like.SOLUTION: There is provided a latent heat storage material composition containing a transition point adjusting assistant, proper amount of ethylene glycol and double salt, suspension for preventing phase separation, a broken overcooling promotion catalyst and a surfactant material in an inclusion with molar weight ratio in 100 wet% range in a rage of mixing ratio of (A) an eutectic salt of a sodium acetate hydrate having a composition of the chemical formula CH3COONa, nH2O (n is 2.8 to 3.3) and (B) a three dimensional composition of sodium thiosulfate of the chemical formula Na2S2O3, nH2O (n is 4.8 to 5.3) and sodium sulfate anhydride of the chemical formula Na2SO4nH2O (n is 0) and proper amount of water of 9/1 to 1/9, especially 3/1 to 1/1.SELECTED DRAWING: Figure 1

Description

The present invention relates to a latent heat storage material. More specifically, in the use of solar thermal passive thermal energy, it compensates for the temperature difference and time lag of randomly generated thermal energy, and harmonizes with the temperature range of heating and hot water supply in houses, buildings, agricultural facilities, etc. Provided is a latent heat storage material composition having a transition point freely adjusted in a range of -50 ° C.

A substance that absorbs and dissipates a large amount of latent heat at a constant temperature transfer during the melting and solidification process stores this latent heat without causing a temperature change, and releases the heat without changing the temperature when necessary. It can be absorbed and used effectively. The present invention relates to a latent heat storage material composition used for an efficient thermal cycle by using a combination of heat energy such as solar heat and exhaust heat that can be recycled and electric power, gas, petroleum, and the like.

Such latent heat storage material compositions generally include various types of organic and inorganic electrolytic hydrates, and their composition is mostly peritectic and requires a higher temperature than that of the melting point that shows harmony in the melting process. did. This situation increases the temperature load related to the constituent molecules, dissociates into an inorganic solid and a saturated aqueous solution at the time of melting, and the heavy mass due to the difference in specific gravity results from the physical phenomenon of sedimentation in the aqueous solution and the ionization tendency of hydronium hydrate Accelerates biphasic formation by intermolecular solution phase. That is, due to the two-layered separation phenomenon that does not occur in a single composition, even when cooled in such a state, the hydrate regeneration (peritectic) is not established, and the heat release of latent heat related to solidification does not occur. there were.

As part of the treatment technology and utilization development related to melting and solidification of these substances, changes in the transition point due to the melting point depressant have been studied. In the results, the composition of the embodiment had two transition points, resulting in inconvenience because the effect of using latent heat was insufficient, such as a decrease in the amount of heat and a fixed heat radiation temperature. Further, in order to effectively use the latent heat of fusion of the latent heat storage material, it has been desired from the viewpoint of thermal efficiency that the composition is required to be melted and solidified to avoid a temperature difference caused by supercooling.

In the present invention, sodium acetate n-hydrate (where n is 3), which is generally effective for application of latent heat storage materials, has a melting point and a freezing point of 57.5 ° C., monoclinic crystal, and the latent heat amount is 264 Jkcal / kg. , A melting point of 48.2 ° C. of a sodium thiosulfate hydrate having a chemical formula of Na ₂ S ₂ O ₃ .nH ₂ O (n is 5), a monoclinic crystal, Density 1.74, calorie 205 Jkcal / kg and chemical formula Na ₂ SO ₄ .nH ₂ O (n = 0) anhydrous sodium sulfate or decahydrate, melting point 32.4 ° C., monoclinic crystal, density 1.46 In addition, the calorific value is 245 Jkal / kg, and the crystal lattice structure has a stable common point, and the desired heat storage material is obtained by setting the transition temperature according to the melting point change in the harmonized trial process of the ternary composition (also called ternary system). I found a possibility.

A temperature range of 40 ° C. ± 3 ° C. is effective for use as a temperature difference related to a temperature range generally suitable for daily life for renewable passive energy and the like. However, each of sodium acetate hydrate, sodium thiosulfate hydrate, and sodium sulfate hydrate is a peritectic composition, and the melting heating temperature of sodium acetate hydrate is higher than that of melting point 57 ° C. 80 ° C ≧ of thiosulfuric acid and sodium sulfate are required, and similarly, as the melting point shows, it is impossible to control the temperature of melting point ≧ exceeding the desired temperature range alone, and thermal damage and thermal control There was a difficulty related to loss.

With this improvement measure, the problem related to the peritectic composition of sodium acetate hydrate is eliminated, and the reforming means that harmonizes the temperature difference of Δ ° C is combined with the sodium thiosulfate composition and sodium sulfate composition to achieve temperature harmony. It came to the conclusion of the favorable aspect which is set as the leading ternary eutectic composition.

When sodium acetate hydrate is the main ingredient, there is a difference in the crystallization growth rate in the basic parameters and comparative data of the latter binary system of eutectic. At such measured value (△ ° C), sodium acetate hydrate is Compared to “2.4 × 10 ⁻¹ cm / sec” and the subsequent crystallization rate of “2.5 × 10 ⁻¹ cm / sec”, the crystal growth difference is about 100 times faster (cm / sec). It was.

The thermal conductivity of the sodium acetate crystal is as low as approximately 32% ≦ “λs = 2.2 × 10 ⁻¹ J / sec.m. ° C.” at 0 ° C. of ice. The expansion coefficient is 11 vol which is the reciprocal of ice. In addition, sodium thiosulfate and sodium sulfate show expansion by coagulation opposite to sodium acetate hydrate, as with ice. The elimination method that leads to expansion by melting without impairing the amount of heat by using this property as an eutectic is preferable for the latent heat storage material composition. Japanese Patent Application Laid-Open No. 62-25188 discloses a suppression means for achieving vol = ± 0 in the process of reducing the expansion coefficient and the phase separation preventing technique into a cross-linked polymer. However, as a result, it is clear from the example data so far that the change in the expansion coefficient has a significant effect on the decrease in the amount of heat stored in the latent heat storage material, and this countermeasure is not perfect in effect. It was.

The difference in speed related to crystallization growth is presumed to be a difference in the strength and weakness of the lattice structure, and is determined by the transparency of the solution in which molecular movement can proceed through the melt without resistance. This difference in crystallization speed is focused on changing the heat transfer function of the latent heat storage material, and a preferred embodiment is constructed for heat transfer harmony using crystal systems with different fundamentals. However, each system further clarifies and solves the necessary countermeasures for the phase separation and supercooling phenomenon.

In particular, the supercooling phenomenon (meta-stabilization) of the sodium thiosulfate composition (melting point 47 ° C) is larger than that of other hydrates. The property which shows a regression aspect is large. The sodium sulfate hydrate and crystallization rate are the same as the sodium thiosulfate hydrate, and the slow phenomenon is the harmony of the lattice structure to absorb and release heat related to the heat transfer efficiency, which is a disadvantage of sodium acetate hydrate. The goal is to improve. This phenomenon is caused by the required material lattice of the system, and uses the properties required by different systems in harmony.

Japanese Patent Laid-Open No. 52-11118 JP 57-153078 A JP 58-99696 A (Special Registration No. 14233329) JP 59-000543 A Japanese Patent Laid-Open No. 59-051974 (Japanese Patent Registration No. 1646850) Japanese Patent Laid-Open No. 01-258784 Japanese Unexamined Patent Publication No. 01-006084 (Japanese Patent Registration No. 1928471) Japanese Patent Laid-Open No. 02-194083 (Japanese Patent Registration No. 2890197) JP 2001-31956 A New Tohoku Chemical Industry Technical Data, Corp Chemical Technical Data

A number of research and development techniques have been disclosed in the past as a technical method mainly intended to eliminate supercooling related to sodium acetate hydrate. In addition, the effectiveness of a technique using attapulgite as a fixed thickener for sodium sulfate decahydrate and sodium tetraborate hydrate or various sodium phosphate hydrates as a crystallization promoting catalyst has been known for a long time. .

Although disclosed as preventing overcooling of a mixed composition of sodium acetate trihydrate and sodium thiosulfate composition, it has a problem that does not lead to the above-mentioned problem being solved effectively. Regarding the melting point change, Japanese Patent Application Laid-Open No. 2-194083 discloses means based on sodium acetate hydrate, ammonium salt, etc., and there is a proposal of sepiolite as a phase separation inhibitor, which suppresses the stability of water molecules possessed by the sepiolite. The effectiveness of water molecule adsorption function and durability in the action and ionization solution was shown.

In view of the above-mentioned properties, the present invention is based on the advantages of sodium acetate hydrate, sodium thiosulfate hydrate, and a ternary mixed crystal having a sodium sulfate composition. Is a means for solving Table 2 and the heat radiation curve diagram 2 and a means for improving the heat transfer with the heat medium (water) related to the solid phase-liquefaction of the latent heat storage composition. It is intended to improve.

Most of the compositions having a melting point of 100 ° C. are mostly peritectic, and the hydrate is first, the harmony of heating temperature difference and melt expansion related to peritectic, second, high temperature Stabilization of seeding technology related to melting and suppression of supercooling and phase separation generation, third, suppression of non-required secondary transition point generation, fourth, ensuring melting temperature and latent heat amount and improving heat transfer, fifth, Achievement of stability and safety of properties in heat and heat history and low cost.

There is a representative example of Japanese Patent Application Laid-Open No. Sho 60-15665 in the disclosed technology relating to temperature conditioning in which sodium acetate is anhydrous and three components of urea and water. Sodium hydrate (57.5 ° C.) is demonstrated based on this disclosure. For the transition point changing composition in which urea is added to the melting point changing agent (decrease) of the sample, the use temperature is set to the primary transition point 45 ° C., and urea is mixed at 10 molar weight. Similarly, two transition points, 43 ° C. and 30.2 ° C., occurred when the mixing ratio was doubled to 20 molar weight. In both samples, the same temperature was confirmed for the secondary transition point.

The peritectic type sodium acetate composition was caused by its peritectic composition, and all melting required heating at 70 ° C. ≧ the melting point. Therefore, in addition to the supersaturation due to heating temperature and the supercooling double phase phenomenon, two transition points occurred. In this case, the heat radiation pattern at the desired primary transition temperature could not be sustained. The object of the present invention could not be achieved by means of harmony related to the transition point of the three components. In this case, overcooling occurred when the melting temperature was 70 ° C. ≧.

From the trial of changing the transition point by the urea blending ratio in this system and the demonstration of blending using other system ammonium salts, the transition point was changed to the basic equilibrium molar amount of the ammonium salt when changing the melting point in the composition system. Except for the case of formulation, all the samples had two transition points. This phenomenon is presumed to be the main cause of the compound form (peritectic), and it can be assumed that it was exposed to the influence of the specific gravity of each system, the temperature difference of the melting point of the structure and the composition, and the ion tendency. The equilibrium point of the ammonia system used in this configuration, except for the blending ratio set to 30.4 ° C., could not be verified because a constant temperature at a higher equilibrium point could not be obtained.

In particular, in the case of a mixed composition including an ammonia-based melting point temperature-decreasing material, heating and dissolution in an atmosphere at a high temperature of 70 ° C. ≧ can be performed in a high-temperature atmosphere by using a supercooling prevention seed agent such as sodium pyrophosphate. However, due to the dissolution (micellar) phenomenon in the solution, the use of ammonia as the melting point depressant of the thermal material promotes supercooling. In addition, the phenomenon of ammonia liberation was remarkable, and there was a problem that required an appropriate means. There are many disclosures including Japanese Patent Application Laid-Open No. 61-429957.

When using an ammonia system such as urea, nitric acid, sulfuric acid system, etc., in the latent heat storage composition for warm heat as a problem related to performance, as described in the previous section, if the temperature exceeds the allowable temperature of the additive ammonia system due to the action of the heating temperature, The compositional separation of ammonia induces the phenomenon of ammonia dissociation. Ammonia dissociated from the system induces rapid heat absorption in the container and induces expansion of vaporization expansion. Meanwhile, unless any preventive measures are taken for temperature control such as stopping heating, the heat storage function is lost due to volume expansion due to volume expansion, and the generation of toxic vaporized ammonia is unfavorable for health.

Therefore, the use of the mixed composition is limited in heating near the transition point from the viewpoint of safety. It has been found in numerous demonstrations that at least its effectiveness is impaired. However, the system aimed at by the present invention is to solve the problem by eliminating the ammonia salt-based synthetic material in the melting point depression for the composite hybrid composition based on the melting point harmony of 40 ° C. ± 3 ° C. It is.

The hydrate of the main material is not limited to a single compound and is a general physical property, and is easily supercooled due to supersaturation due to melting, and phase separation is remarkable due to the difference in system density. Conventionally disclosed means for preventing supercooling each time the phase change is repeated, the hydrate expands the separation of water molecules, leading to the loss of the latent heat storage function.

The main cause is a physical phenomenon related to the thermal history exceeding the range of origin of peritectic system due to heating exceeding the limit temperature related to melting on the low melting point side of the two phases of peritectic melting point. As described above, a separation phenomenon occurs in which solid molecules dissociate in an aqueous solution due to a two-layer specific gravity due to a difference in component density in a molten state. Once dissociation has started, a peritectic hydrated crystal balanced through the interface cannot be obtained, and the balance function related to latent heat is lost, so that the heat storage effect utilizing latent heat, which is the purpose of the present invention, cannot be expected.

In order to obtain a latent heat radiation heat storage material corresponding to the heat history according to the mass at a constant temperature for a certain time at the transition point of heating, cooling, and heat radiation, it is stable at the appropriate temperature related to melting of the composition system and heat resistant aging resistance Therefore, the proper proportion of the eutectic composition of the latent heat storage material that can be used and a good suspension are important.

As part of the suspension function, the hydrogel is a polymer such as polyvinyl alcohol, sodium polyacrylate, stearic acid, etc., polysaccharides such as DEAE cellulose, glycerin and other organic substances, and thixotropic inorganic mineral clays such as kaolinite and halo. The range of PH 5.0 to 7.7 is used for sites, powdered silica (200 mesh range), diatomaceous earth (amorphous silicon dioxide 600 mesh), bentonite, and attapulgite powder (60 mesh range). It is common.

Depending on the composition of the suspension, these suspensions have a large ion exchange capacity, and in thermal history and resolution, changes in thixotropy fluidity due to hydrolysis or hyphae and aging deterioration, the adsorptive power of the required function to the suspension However, the risk of losing the thickening power is high, and there is a defect that the function is easily lost, and the original purpose as a latent heat storage material has not been achieved.

A good demonstration of the effect of preventing phase separation and supercooling by the water molecule adsorption function by adding sepiolite to the suspension for preventing phase separation of sodium acetate hydrate is disclosed.

However, it has been found that chrysotile (asbestos component) is formed in a specific homogenous material in a small amount at the origin and mineral species of sepiolite. It is publicly announced that the content of such chrysotile is as small as 3% ≦ per 100 mol% of the sepiolite. As a suspension, there is no impact on the living environment and health from the composition material, but it is a compound that deals with safety reputation from general social wisdom and uses fine powdered zeolite and attapulgite as substitute substances for the function By using alternative means, a corresponding effect can be obtained.

However, in practice, a mixture of zeolite and attapulgite used in combination with an aqueous solution was affected by thixotropic properties in the process of mixing, and was easily powdered and had problems with dispersibility and compositional interface activity.

The purpose of the present invention is to utilize a temperature harmonized to Δ ° C in the range of the latent heat release temperature near the transition point required by the system in the range of 35 ° C to 53 ° C. A eutectic composition in which ethylene glycol and double salts are appropriately added to a ternary eutectic temperature adjusting component of sodium thiosulfate hydrate of eutectic related to sodium acetate hydrate and sodium sulfate anhydride. It is what.

As described above, the ternary eutectic composition is effective for changing the transition temperature and maintaining the amount of heat. However, in the conventional embodiment, the peritectic compound is generated at the time of heating and melting due to the difference in the molecular density and lattice of the components. There is a layering phenomenon, an anhydrous crystal in the lower layer, and an intermolecular separation phenomenon in a saturated aqueous solution in the upper layer. Separation and supercooling are fatal phenomena for the latent heat material. It was insufficient.

The difference in crystallization related to the solidification of sodium acetate hydrate is that the different properties of the lattice of sulfuric acid-based sodium thiosulfate and sodium sulfate compositions have a good effect on the harmony between crystallization growth rate and temperature. The effect of a favorable aspect is demonstrated for the setting of a point. Various previously proposed thickeners are prone to changes in maintaining their functions due to their specific regression (change) factors (eg heat resistance, chemical resistance, reactivity, microbial resistance, dispersion compatibility, water content). There was a problem in application due to insufficient response effect.

There is no chrysotile component in zeolite, smectite, attapulgite containing palygorskite, etc. as a solution to replace some sepiolites that form chrysotile (asbestos), and these combined effects make the embodiment similar to sepiolite Things are valid.

The crystal structure of zeolite is similar to that of sepiolite's staggered lattice, larger than water molecules and nitrogen molecules, and has pores with tunnels of approximately 8.0 x 5.0 mm. In the presence of the channel. In such a channel, the presence of exchangeable ions and water molecules arranged in the components are confirmed, and the surface body is a model knight structure.

The configuration is a crystal edge similar to the surface of the phyllosilicate, and this structure has an adsorption function with an infinite number of active sites along the channel, and requires a track record of use as an improved material. Such palygorskite and attapulgite are hydrogels having a lath-like particle (gel-like viscosity) and have such a combination effect.

This is an embodiment that is used for latent heat storage materials with regard to these nutrients, especially water molecule adsorption-desorption, function, heat resistance, chemical resistance, and maintenance resistance, and in terms of functionality in view of the sepiolite structure. In addition, we tried to make sure the eutectic composition separation prevention technology using a complex that complements the specific functions such as zeolite, smectite having approximate functions, attapulgite including palygorskite structure, and the like.

When the suspension powder is mixed with the composition in an aqueous solution in advance, 0.01-10 mol of dodecyl sodium sulfate or ethoxylated amic acid, which acts to eliminate powder formation and surface activity, is used. The effect of using an appropriate amount by weight% causes uniform dispersion, surface tension and interfacial activity wetting in the mixed crystal system, and promotes the effect of suspension and the amplification of intermolecular heat transfer.

Water molecules of sodium acetate mixed crystals that change phase at a constant temperature are adsorbed in the suspension channels in a balanced manner, preventing water molecules from separating and exhibiting an aqueous solution adsorption function similar to sepiolite, and no inhibition phenomenon due to mixing is observed. It was.

Sepiolite fiber talc-like powder used in the conventional suspension system confirms the necessity of proper function corresponding to both phase separation and prevention of supercooling due to the synergistic effect of thickening and adsorption function However, in order to keep the solidification start temperature at the time of supercooling to a minimum difference, the following item was tried in view of the fact that the solid crystal growth modulation for promoting solidification could not be satisfied.

As a catalyst for promoting crystallization of the mixed crystal composition, cryolite, tetrasodium pyrophosphate, potassium pyrophosphate and chelate compounds such as EDTA4Na-4H ₂ O, EDTA similar to ethylenediaminetetraacetic acid dihydrogen disodium hydrate are used. -3Na · 2H ₂ O, EDTA-2Na, 2H ₂ O, EDTA-H · 3Na, 3H ₂ O, NTA-3Na, H ₂ O (sodium nitrilotriacetate), etc. Use compounds.

As a catalyst for promoting breakthrough cooling, by adding 0.1 to 30 mol% of the composition to 100 mol% of the ternary composition, heat resistance at an excessive boiling point is required. It is characterized by being a good latent heat storage composition that releases supercooling at the transition point and exhibits a constant latent heat radiation function in such a temperature range.

In the present invention, an appropriate amount of sodium dodecyl sulfate and ethoxylated amic acid are used for the surface activity of a seed material having a suspension function as a catalyst for promoting solidification and the aqueous solution, and a good catalytic action is obtained for the modulation of crystal habit in the aqueous solution. This is an embodiment to promote.

That is, in the present invention, an eutectic salt of sodium acetate hydrate having a composition of the chemical formula CH ₃ COONa · nH ₂ O (n is 2.8 to 3.3) is converted to a chemical formula Na ₂ S ₂ O ₃ · nH. ₂ O (n is 4.8-5.3) and the chemical formula Na ₂ SO ₄ . Effective use of ethylene glycol and salts (potassium, sodium) in 100% by weight temperature control auxiliary material adjusted to increase or decrease in effective water with the appropriate amount of nH ₂ O (n is usually 10) sodium sulfate Is.

Formula Na 3 _ALF 6, ₆ fluorinated aluminate mixtures of two or more to 0.1 to 30 mol% and supercooling promoting seed material chosen composition separation inhibitor from the class of synthetic smectite attapulgite composite zeolite Sodium phosphate (cryolite), chemical formula Na ₂ B ₄ O ₇ 10H ₂ 0 · sodium tetraborate, chemical formula Na ₄ P ₂ O ₇ 10H ₂ O · sodium pyrophosphate hydrate, chemical formula KH ₂ PO ₄ · pyrophosphate Potassium, chemical formula EDTA-4Na.4H ₂ O, EDTA ₂ H ₂ Na. This is a preferred embodiment in which 0.1 to 30 mol% of a combination catalyst composed of two or more selected from chelates such as 2H ₂ O is used.

The ratio of the mixing ratio (mole weight%) of the zeolite selected from synthetic smectite, palygorskite, attapulgite, and the other three compounds to the phase separation inhibitor suspension (thickener) is 9/1 to 1/9. In particular, the mixture of 3/1 to 1/1 is a preferred embodiment because 0.1 to 20 mol% by weight can increase the effect by adding a smaller amount.

The latent heat storage material composition of the present invention is a composite composed of sodium acetate eutectic hydrate, synthetic smectite, palygorskite, attapulgite, or zeolite alone, and easily melts in a low temperature range in which the melting temperature is adjusted to 60 ° C. And store heat. By adding a proper amount of thickener, a stable network structure that avoids phase separation of the mixed crystal composition is constructed.

Furthermore, the thermal history of the breakthrough cooling means selected from the composite catalyst compounds of various chelates such as cryolite, sodium tetraborate hydrate, sodium pyrophosphate, potassium pyrophosphate, and EDTA-4Na4H ₂ O In all of the trials of the catalytic effect, effective results and effects were confirmed in the above-mentioned ambient temperature range.

In comparison with the results of the conventional sepiolite alone, there has been no practical discoloration. This result shows that the supercooling is adjusted to work reliably within the temperature range of 5 ° C ≦, the reduction of entropy heat loss and the latent heat release breaks the supercooling at 38 ° C, and the transition point ranges from 35 ° C to 54 ° C. As a result, the transition point was arbitrarily set, and a certain latent heat radiation was ensured to improve reliability.

The required heat quantity is 233 JKcal / kg, and the density per volume and the required heat quantity are large, and the heat transfer effect is approximately 30% ≧ providing a latent heat storage material.

Sodium acetate hydrate used as the main material of the latent heat storage material of the present invention is represented by the chemical formula CH ₃ COONa.nH ₂ O (n is 3.0). The so-called sodium acetate hydrate contains a slightly increased or decreased amount of crystal water. When n = 3, sodium acetate anhydrous or sodium acetate hydrate is added to the chemical formula Na ₂ S ₂ O ₃ .nH ₂ O (n is 4.8 to 5.3) sodium thiosulfate hydrate and the chemical formula Na ₂ SO ₄ was added to hydrolyze 1 to 20 mol% by weight in the composite mixed crystal hydrate by addition of sodium sulfate is a preferred embodiment to adjust the amount of heat maintained in the transition range, more in many water molecules, Moreover, even if it is at least, it will have a bad influence on supercooling and a heat storage amount.

The addition amount of smectite, palygorskite and attapulgite (60 mesh ≧), zeolite 200 mesh ≧ fine powder is added to the suspension with respect to 100 mol% by weight of the sodium acetate hydrated mixed crystal composition used as the main material in the present invention. The composite of zeolite and fine powders of other inorganic minerals is 0.5 to 30% by weight with respect to 100% by weight.

If the amount added is larger than this, the molten solution becomes too viscous to be practical. On the other hand, if the addition amount is less than this range, a functional material as intended by the present invention cannot be obtained. In the above range, the amount added can be arbitrarily selected depending on the temperature range in which the latent heat storage material is used.

In general, the electrolytic hydrate system is likely to cause a phase separation phenomenon related to supercooling in a supersaturated atmosphere in the melting process, and the heat storage effect is gradually reduced by repeating melting and solidification. Therefore, in the present invention, it is preferable to add 0.1 to 30 mol% of synthetic smectite, zeolite, palygorskite, or attapulgite to the suspension for suppressing phase separation.

That is, in a more preferred embodiment of the present invention, the synthetic smectite / sodium salt is mixed with 100 mol% by weight of a mixed crystal composition composed of sodium thiosulfate and sodium sulfate as a main crystal eutectic of sodium acetate hydrate. Zirconium palygorskite or attapulgite powder mixed with 0.1 to 15 mol% by weight, and the latent heat storage material composition added in practice is, for example, the temperature difference randomly generated due to seasonal changes and weather conditions such as solar heat Heat resistance that can correspond to the range of use (upper limit 80 ° C-lower limit 25 ° C) is required, and in the phase change, the required heat amount is reduced in harmony with the set transition point (38 ° C-53 ° C). It is characterized by a good mode in which the solid-liquid acts without fail.

Here, attapulgite is a hydrous magnesium silicate-based ceramic having a palygorskite structure that requires a structural formula of chemical formula (Mg.AL) ₂ SI ₄ O ₁₀ (OH) .4H ₂ O. It is a model of a naturally occurring fibrous clay mineral, and the porous fibrous structure and the ion exchange properties of the interlayer cations are attributed to a hydrogel composed of lath-shaped particles having a function of incorporating water molecules and organic molecules.

Zeolite is abundant and inexpensive in terms of resources, although there are differences in structure due to origin. The combination of structural formulas is an improved synthesis of 2000 pairs ≧, for example, a magnesium silicate-based inorganic product known for various syntheses that have a proven track record as an important catalyst in water adsorption and petroleum synthesis.

The structure consists of extremely fine porous crystals, and there are innumerable tunnel-like pores having a micropore diameter. The unique adsorption effect by the tunnel having the same shape pores as water molecules and lattices prevents the separation of water molecules and lattices by holding the crystal water and water molecules, and acts as an anti-separation agent for the composition. This characteristic property action shows a stable persistence in the thermal history, and the origin and characteristics of this characteristic have confirmed the approximate action with sepiolite.

The vertical axis represents temperature, the horizontal axis represents the required time, and the latent heat storage material of the invention has absorbed heat. The latent heat storage material has a unique melting point A1 and the parabolic change on the horizontal axis is a phase change from solid to liquefaction. Indicates. Total melting is shown according to the horizontal axis. In general, when the total melting is completed, the material temperature rapidly changes to sensible heat as shown in the figure, indicating a temperature increase. An arrow indicating reversibility related to solidification is a heat radiation temperature of latent heat of solidification. The values of solidification latent heat release and melting heat absorption show the moving state with a constant parabolic curve in the atmosphere. It is a comparison figure which shows the heat absorption and heat dissipation curve of the type | system | group which mix | blended melting | fusing point depressant (urea) etc. with the comparative sample on the conditions similar to FIG. Two different temperature transition points occur, indicating the occurrence of heat absorption / release that is not stable in terms of heat utilization.

Synthetic smectite, zeolite, palygorskite, and attapulgite can be used as a mixture, either in the form of a granular clay or by removing impurities further and purely (200 mesh ≧).

Generally, these materials are commercialized to a purity of 90% or more, 70 to 90%, 70% or less, and are classified into high powder, normal powder, and low powder, and are classified into pure powder, normal powder, and clay particles. . The palygorskite used in the present invention is preferably selected from the purity standards of palygorskite from which attapulgite is a main component and impurities are removed and smectite separated from mica.

Hereinafter, the present invention will be specifically described with reference to examples. However, the present invention is not limited to these examples. The sample is measured by JIS (K) 7122 measurement and differential scanning calorimeter measurement.
Formula _{Na 2 S 2 O 3 · nH} 2 O of sodium thiosulfate hydrate sodium acetate hydrate was added water chemical formula _{CH 3 COONa · nH 2 O (} n is from 2.8 to 5.3) (n 4.8-5.3), a eutectic complex hydrate was prepared by combining the ternary composition of sodium sulfate chemical formula Na ₂ SO ₄ .nH ₂ O (n is 0) as follows.

Ternary mixed crystal hydrate composed of sodium acetate hydrate, sodium thiosulfate hydrate, and sodium sulfate anhydrous: 100 mol% by weight, smectite attapulgite (including palygorskite): 1.0-3 .5 mol% by weight, zeolite: a combination of sodium tetraborate hydrate / sodium pyrophosphate hydrate / potassium pyrophosphate / EDTA-4Na4H ₂ O with respect to a mixture of 1.0 to 3.5 mol% by weight According to each added weight shown in Table 1 in which the composition was adjusted to a constant amount (3.0 mol% by weight), 5 sets (20 samples) were prepared with 4 samples / set of the latent heat storage material composition. Table 1 shows the average value of one class of changes in transition point and heat dissipation in a thermostat (made by Isuzu) measured at −20 ° C. to 125 ° C. according to a temperature duration curve at a freezing point of 42 ° C. of the sample temperature. .

After the heating is completed, the phase change occurs smoothly. After the supercooling is broken at 38 ° C. and the temperature rises to 42 ° C., the process is repeated 500 times continuously until the phase change is completed. No change was confirmed. The latent heat parabolic curve at the transition point in Example 1 is shown in FIG.

The chemical formula Na ₄ P ₂ O ₇ .100 is 100 mol% mixed with urea or ammonium salt in a range of 10 to 40 wt% with respect to 100 mol% of sodium acetate hydrated compound. 10H ₂ O sodium pyrophosphate decahydrate, chemical compound of KP ₂ O ₇ potassium pyrophosphate, or 5 samples each of palygorskite attapulgite zeolite added with 3% by weight alone as shown in Table 2 ( An attempt was made to measure the freezing point in the same manner as in Example 1 for a weight of 20 g), and FIG. 2 shows a latent heat radiation curve of Comparative Example 2 of the phase transition point (melting-solidification).

It is a latent heat storage composition in which a solid-liquid transition point can be set in units of 1.0 ° C within a general living temperature range of 35-52 ° C. Utilizing solidification latent heat and melting sensible heat in a range of passive heat energy (25 ° C to 80 ° C) such as solar heat and exhaust heat, each of which is a small and large amount of heat as a required heat storage device material that compensates for the time lag with low-cost power It is intended to provide equipment.

Claims (3)

An eutectic salt of sodium acetate hydrate having the composition (A) of the chemical formula CH ₃ COONa, nH ₂ O (n is 2.8 to 3.3) is converted to a chemical formula Na ₂ S ₂ O ₃ , nH ₂ O (n is 4.8-5.3) sodium thiosulfate and the chemical formula Na ₂ SO ₄ nH ₂ O (n is 0) sodium sulfate anhydride and a suitable amount of water-containing ternary composition (B) , 9/1 to 1/9, in particular 3/1 to 1/1 in the range of 100 wt% molar weight ratio containing transition point adjusting aids and proper amounts of ethylene glycol and salt. The latent heat storage material composition according to claim 1, further comprising a suspension for preventing phase separation, a breakthrough cooling promoting catalyst, and a surfactant. The chemical formula (MgSi) having a chemical formula (Mg.AL) ₂ SI ₄ O ₁₀ (OH), 4H ₂ O palygorskite or palygorskite as a separation inhibiting carrier for chloride compositions belonging to the range of hydrogen ion concentration (PH 7.5 to ₁₀ ) ₈ [O ₂₀ (OH) ₂ ] · 8H ₂ O attapulgite group (A), A / B mixing ratio (molar weight ratio) of zeolite (B) of chemical formula Me ² / nO ₃ , xSiO ₂ , yH ₂ O However, 100 mol% in the range of 9/1 to 1/9, particularly 3/1 to 1/1, includes 0.1 to 30 mol weight ratio of the phase separation preventing suspension. The latent heat storage material composition according to claim 1. As a breakthrough cooling accelerating catalyst for a ternary composition having a sodium acetate eutectic composition, a composite of a chemical formula Na ₄ P ₂ O ₇ , 10H ₂ O sodium pyrophosphate hydrate and a chemical formula K ₂ P2O ₇ potassium pyrophosphate ( A) and a chelate compound (B) of the chemical formula EDTA-4Na · 4H ₂ O and sodium ethylenediaminetetraacetate, wherein the A / B mixing ratio (mol%) is 9/1 to 1/9, particularly 3/1 to 1 / 0.1-30 molar weight ratios 1 at a rate within the scope 100Wet% and a surfactant in the formula _{CH 3 (CH 2) 10 CH} 2 CH 4 SO 3 Na sodium dodecylbenzenesulfonate, 0.1~10wet% The latent heat storage material composition according to claim 1, wherein a molar weight ratio in the range of 1 is included.

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