Theoretic Prediction of Melting Temperature and Latent Heat for a Fatty Acid Eutectic Mixture

This study focuses on the preparation, thermal properties of alkanes eutectic mixtures (n-Octadecane/n-Eicosane, n-Octadecane/n-Docosane and n-Heptadecane /n-Eicosane) as candidate phase change material (PCM) for low temperature latent heat storage systems in building envelopes. Their melting temperature and latent heat were tested by Differential scanning calorimetry (DSC). The testing values were closed to calculation values of accepted theory that ensured the reliability of those datas. The results indicated n-Octadecane/n-Docosane eutectic mixture was more promising PCM for buildings in terms of melting temperature (25.3°C) and latent heat values of melting (158.2J/g).

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Novel metal coated nanocapsules of ethyl esters fatty acid eutectic mixture as phase change material with enhanced thermal conductivity for energy storage applications

Thermochimica Acta ◽

10.1016/j.tca.2020.178581 ◽

2020 ◽

Vol 687 ◽

pp. 178581 ◽

Cited By ~ 3

Author(s):

S. Dhivya ◽

S. Imran Hussain ◽

S. Kalaiselvam

Keyword(s):

Thermal Conductivity ◽

Fatty Acid ◽

Energy Storage ◽

Phase Change ◽

Eutectic Mixture ◽

Ethyl Esters ◽

Energy Storage Applications ◽

Change Material ◽

Fatty Acid Eutectic ◽

Enhanced Thermal Conductivity

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Research on the Thermo Physical Properties of Lauric Acid-Capric Acid Binary Mixture Phase Change Materials

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.226-228.1704 ◽

2012 ◽

Vol 226-228 ◽

pp. 1704-1708

Author(s):

Quan Zhou ◽

Yi Zhang ◽

Hong Bin Guo ◽

Qing Hai Li ◽

Dong Xu Li

Keyword(s):

Thermal Conductivity ◽

Fatty Acid ◽

Binary Mixture ◽

Phase Change ◽

Melting Temperature ◽

Binary Mixtures ◽

Latent Heat ◽

Lauric Acid ◽

Capric Acid ◽

Heating And Cooling

Lauric acid(LA) and capric acid(CA) were mixed into binary mixture, whose melting temperature was predicted with Schroder’s equation and tested in step cooling curve method. Then latent heat was tested by DSC, and T-history method was used to test thermal conductivity of binary mixtures, heating and cooling characteristics were studied through expanded perlite(EP) adsorption of binary mixtures. Results show that Schroder’s equation can be used to predict melting temperature of fatty acid, and binary mixture prepared of 6:4 molar ratio has a high latent heat and its temperature is within a range that meets indoor comfort temperature. Thermal conductivity and the heating and cooling characteristics of the mixtures reveals that the thermal conductivity of fatty acid phase change material(PCM) is low, which restricts its latent heat release rate.

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Preparation and Properties of Capric-Lauric-Palmitic Acid Eutectic Mixtures/Expanded Graphite Composite as Phase Change Materials for Energy Storage

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1028.40 ◽

2014 ◽

Vol 1028 ◽

pp. 40-45 ◽

Cited By ~ 3

Author(s):

Xue Huang ◽

Yling De Cui ◽

Bu Ning Zhang ◽

Guo Qiang Yin ◽

Guang Zhu Feng

Keyword(s):

Thermal Conductivity ◽

Phase Change ◽

Melting Temperature ◽

Latent Heat ◽

Phase Change Materials ◽

Ternary Eutectic ◽

Eutectic Mixture ◽

Expanded Graphite ◽

Mass Ratio ◽

Eutectic Mixtures

This work is focused on the preparation and properties of ternary fatty acid eutectic mixtures/ expanded graphite form-stable phase change materials (PCMs). Based on the theoretical calculation of the mass ratio and ternary eutectic melting temperature, the ternary eutectic mixture of capric acid (CA), lauric acid (LA) and palmitic acid (PA) was prepared firstly, which is for the sake of decreasing the phase transformation temperature. Thermal characteristics such as melting temperature and latent heat of fusion of these developed eutectics measured by using Differential Scanning Calorimetry (DSC) technique, which also showed that the eutectic mixture was composed by CA, LA and PA in the mass ratio of 59.7:30.1:10.02. Then the CA–LA–PA was absorbed in expanded graphite (EG), which acts as a supporting material, the optimum mass ratio of CA–LA–PA to EG is 17:1. The CA–LA–PA/EG composites were characterized by the scanning electronic microscope (SEM), differential scanning calorimeter (DSC). The SEM observations showed that the CA–LA–PA was adsorbed into the porous structure of EG, instead of any chemical action. The DSC results indicated that the phase change temperature and latent heat of the CA–LA–PA and CA–LA–PA/EG were 19.92 °Cand 19.48 °C, and 135.49 J/g and 130.73 J/g respectively. The thermal conductivity of CA–LA–PA /EG composite PCM was improved by the high thermal conductivity of the EG. Thermal cycling test showed that the CA–LA–PA/EG composite had a good thermal reliability. All results indicated that CA–LA–PA/EG composite PCM has a proper melting temperature and latent heat for building energy conservation.

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Prediction of Melting Temperature and Latent Heat for Low-melting Metal PCMs

Rare Metal Materials and Engineering ◽

10.1016/s1875-5372(16)30091-1 ◽

2016 ◽

Vol 45 (4) ◽

pp. 874-880 ◽

Cited By ~ 5

Author(s):

Aigang Pan ◽

Junbiao Wang ◽

Xianjie Zhang

Keyword(s):

Melting Temperature ◽

Latent Heat

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Molten Salt Spectroscopy for Quantification of Radiative Absorption in Novel Metal Chloride-Enhanced Thermal Storage Media

Journal of Solar Energy Engineering ◽

10.1115/1.4029934 ◽

2015 ◽

Vol 137 (4) ◽

Cited By ~ 8

Author(s):

Philip D. Myers ◽

D. Yogi Goswami ◽

Elias Stefanakos

Keyword(s):

Heat Transfer ◽

Transition Metal ◽

Melting Temperature ◽

Latent Heat ◽

Thermal Storage ◽

Metal Chloride ◽

Eutectic System ◽

Metal Chlorides ◽

Storage Media ◽

Radiative Absorption

This study describes the development and characterization of novel high-temperature thermal storage media, based on inclusion of transition metal chlorides in the potassium–sodium chloride eutectic system, (K–Na)Cl (melting temperature of 657 °C, latent heat of 278 J/g). At the melting temperature of (K–Na)Cl, infrared (IR) radiation can play a major role in the overall heat transfer process—90% of spectral blackbody radiation falls in the range of 2–13 μm. The authors propose inclusion of small amounts (less than 0.2 wt.%) of IR-active transition metal chlorides to increase radiative absorption and thereby enhance heat transfer rates. A new IR-reflectance apparatus was developed to allow for determination of the spectral absorption coefficient of the newly formulated phase-change materials (PCMs) in the molten state. The apparatus consisted of an alumina crucible coated at the bottom with a reflective (platinum) or absorptive (graphite) surface, a heated ceramic crucible-holder, and a combination of zinc sulfide (ZnS) and zinc selenide (ZnSe) windows for containment of the salt and allowance of inert purge gas flow. Using this apparatus, IR spectra were obtained for various transition metal chloride additives in (K–Na)Cl and improved IR activity, and radiative transfer properties were quantified. Further, thermophysical properties relevant to thermal energy storage (i.e., melting temperature and latent heat) are measured for the pure and additive-enhanced thermal storage media.

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