The Phase Change Characteristics of Capric Acid-based Binary Low Eutectic Mixtures Adsorbed in Expanded Graphite

Abstract

Capric acid-hexadecanol (CA-H) and capric acid-paraffin section (CA-PS) composite phase change materials were prepared by a melting−blending method, and two new composite phase change energy storage materials based on expanded graphite were obtained by the physical adsorption method. The results showed that the optimum mass ratio of CA-H and CA-PS were 74:26 and 81:19, respectively. It was found via FT-IR that CA, H, and PS acted together by molecular force without chemical reaction. The phase transition temperature of CA-H and CA-PS was 24.22 and 26.99 °C, respectively, and the latent heat of phase transition was 190.5 and 153.7 J/g, respectively. On the other hand, the best mass ratio of CA-H/EG and CA-PS/EG was 11:1 and 7:1, respectively. On the basis of SEM and FT-IR results, it was found that CA-H and CA-PS were uniformly distributed in the pores of EG by physical action; the melting and freezing temperatures are in the range of 21∼28 °C, and the latent heat was in the range of 133∼178 J/g by DSC. CA-H/EG and CA-PS/EG had good thermal and chemical stability after 1000 accelerated melting−freezing cycling tests. According to the TG and thermal storage experiments, CA-H/EG and CA-PS/EG had excellent heat resistance, and the high thermal conductivity of EG promoted the thermal storage and release rate of CA-H and CA-PS. Therefore, CA-H/EG and CA-PS/EG can be used as candidate materials in the fields of building energy savings.

Study of Capric–Palmitic Acid/Clay Minerals as Form-Stable Composite Phase-Change Materials for Thermal Energy Storage

“…In recent years, with rapid economic development and the shortage of fossil energy, energy storage and the effective use of new energy have attracted considerable attention. As an important method to effectively improve energy efficiency, thermal energy storage has become a key research topic. − The thermal energy storage technology can be divided into sensible heat storage, chemical reaction energy storage, and latent heat storage, according to the form of energy storage . Sensible heat storage has certain shortcomings, such as a low energy storage density and large temperature changes associated with heat storage and release.…”

CuO Nanoparticle@Polystyrene Hierarchical Porous Foam for the Effective Encapsulation of Octadecanol as a Phase Changing Thermal Energy Storage Material

“…24 To overcome these limitations, in addition to PCM microcapsules, 25−27 the application of shapestable porous materials as a PCM carrier has received great interest in the literature. 28−32 To date, porous clay, 33 mineralbased materials, 14 metallic foams, 34 porous carbon, 35 and porous polymers 36,37 are the most commonly used framework materials for shape-stabilized PCM. High internal phase emulsion templated polymers (PHP) as porous polymers have been used in a wide variety of applications such as adsorption, 38,39 purification, 40,41 separation, 42 controlled release, 43,44 and scaffolding, 45 and there is limited research in energy storage application.…”

Preparation and Characterization of Lauric–Myristic Acid/Expanded Graphite as Composite Phase Change Energy Storage Material

“…Phase change materials used in construction must meet its phase transition temperature were within the scope of the indoor temperature, latent heat of large, stable chemical performance, not leak and metamorphism, etc. [17,18]. According to the phase state, phase change materials can be divided into solid-solid phase change materials [19], solid-liquid phase change material [20], solid-gas phase change material, and liquid-gas phase change material.…”