scholarly journals The Role of H-bonding in Phase Change Materials

2019 ◽  
Author(s):  
Karolina Matuszek ◽  
R. Vijayaraghavan ◽  
Mega Kar ◽  
Douglas Macfarlane
Keyword(s):  
Phase Change ◽  
Phase Change Materials ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Hirshfeld Surface ◽  
Industrial Processes ◽  
Heat Of Fusion ◽  
Organic Salts ◽  
Promising Alternative

Phase change materials (PCMs) which melt in the temperature range of 100-230 °C, are a promising alternative for the storage of thermal energy. In this range, large amounts of energy available from solar-thermal, or other forms of renewable heat, can be stored and applied to domestic or industrial processes, or to an Organic Rankine Cycle (ORC) engine to generate electricity. The amount of energy absorbed is related to the latent heat of fusion (ΔH<sub>f</sub>) and is often connected to the extent of hydrogen bonding in the PCM. Herein, we report fundamental studies, including crystal structure and Hirshfeld surface analysis, of a family of guanidinium organic salts that exhibit high values of ΔH<sub>f</sub>, demonstrating that the presence and strength of H-bonds between ions plays a key role in this property.

scholarly journals The Role of H-bonding in Phase Change Materials

2019 ◽  
Author(s):  
Karolina Matuszek ◽  
R. Vijayaraghavan ◽  
Mega Kar ◽  
Douglas Macfarlane
Keyword(s):  
Phase Change ◽  
Phase Change Materials ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Hirshfeld Surface ◽  
Industrial Processes ◽  
Heat Of Fusion ◽  
Organic Salts ◽  
Promising Alternative

Phase change materials (PCMs) which melt in the temperature range of 100-230 °C, are a promising alternative for the storage of thermal energy. In this range, large amounts of energy available from solar-thermal, or other forms of renewable heat, can be stored and applied to domestic or industrial processes, or to an Organic Rankine Cycle (ORC) engine to generate electricity. The amount of energy absorbed is related to the latent heat of fusion (ΔH<sub>f</sub>) and is often connected to the extent of hydrogen bonding in the PCM. Herein, we report fundamental studies, including crystal structure and Hirshfeld surface analysis, of a family of guanidinium organic salts that exhibit high values of ΔH<sub>f</sub>, demonstrating that the presence and strength of H-bonds between ions plays a key role in this property.

scholarly journals Effect of phase change materials on the performance of direct vapor generation solar organic Rankine cycle system

Energy ◽  
2021 ◽  
Vol 223 ◽  
pp. 120006
Author(s):  
Jahan Zeb Alvi ◽  
Yongqiang Feng ◽  
Qian Wang ◽  
Muhammad Imran ◽  
Gang Pei
Keyword(s):  
Phase Change ◽  
Phase Change Materials ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Vapor Generation ◽  
Cycle System

scholarly journals The role of phase change materials for the sustainable energy

2016 ◽  
Vol 10 ◽  
pp. 00068 ◽  
Author(s):  
Marta Kuta ◽  
Dominika Matuszewska ◽  
Tadeusz Michał Wójcik
Keyword(s):  
Phase Change ◽  
Phase Change Materials ◽  
Sustainable Energy

scholarly journals Role of Phase Change Materials Containing Carbonized Rice husks on the Roof-Surface and Indoor Temperatures for Cool Roof System Application

Molecules ◽  
2020 ◽  
Vol 25 (14) ◽  
pp. 3280
Author(s):  
Hong Gun Kim ◽  
Yong-Sun Kim ◽  
Lee Ku Kwac ◽  
Mira Park ◽  
Hye Kyoung Shin
Keyword(s):  
Thermal Conductivity ◽  
Phase Change ◽  
Phase Change Materials ◽  
Paraffin Wax ◽  
Heat Absorption ◽  
Rice Husks ◽  
Indoor Temperature ◽  
Cool Roof ◽  
Plastic Composites

This study researches the effect of phase change materials (PCMs) containing carbonized rice husks (CRHs) in wood plastic composites (WPCs) as roof finishing materials on roof-surface and indoor temperatures. A cool roof miniature model was prepared, and measurements were taken using three fixed temperatures of 30 to 32 °C, 35 to 37 °C, and 40 to 42 °C. Sodium sulfate decahydrate (Na2SO4·10H2O) and paraffin wax were selected as the PCMs. CRHs were used as additives to improve the thermal conductivities of the PCMs. At lower fixed temperatures such as 30 to 32 °C and 35 to 37 °C, the rates of increase of the surface temperatures of roofs containing CRHs with Na2SO4·10H2O, and paraffin wax, were observed to gradually decrease compared to those of the roofs without PCMs. The indoor temperatures for the above-mentioned PCMs containing CRHs were maintained to be lower than those of the indoors without PCMs. Additionally, as the CRH content in the PCM increased, the rates of increase of the roof-surface and indoor temperatures decreased due to a faster roof heat absorption by PCMs through the improved thermal conductivity of CRHs. However, under higher artificial temperatures such as 40 to 42 °C, Na2SO4·10H2O with CRHs exhibited no effect due to being out of latent heat range of Na2SO4·H2O. For paraffin wax, as CRH content increased, their roof- surface and indoor temperatures decreased. Especially, the surface temperature of the roof containing paraffin contained 5 wt.% CRHs reduced by 11 °C, and its indoor temperature dropped to 26.4 °C. The thermal conductivity of PCM was enhanced by the addition of CRHs. A suitable PCM selection in each location can result in the reduction of the roof-surface and indoor temperatures.

scholarly journals Edible Oils as Practical Phase Change Materials for Thermal Energy Storage

2019 ◽  
Vol 9 (8) ◽  
pp. 1627 ◽  
Author(s):  
Samer Kahwaji ◽  
Mary Anne White
Keyword(s):  
Thermal Stability ◽  
Energy Storage ◽  
Phase Change ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Phase Change Materials ◽  
Edible Oils ◽  
Coconut Oil ◽  
Heat Of Fusion ◽  
Vegetable Shortening

Edible oils could provide more accessible alternatives to other phase change materials (PCMs) for consumers who wish to build a thermal energy storage (TES) system with sustainable materials. Edible oils have good shelf life, can be acquired easily from local stores and can be less expensive than other PCMs. In this work, we explore whether margarine, vegetable shortening, and coconut oil are feasible PCMs, by investigations of their thermal properties and thermal stability. We found that margarine and vegetable shortening are not useful for TES due to their low latent heat of fusion, ΔfusH, and poor thermal stability. In contrast, coconut oil remained thermally stable after 200 melt-freeze cycles, and has a large ΔfusH of 105 ± 11 J g−1, a low degree of supercooling and a transition temperature, Tmpt = 24.5 ± 1.5 °C, that makes it very useful for TES in buildings. We also determined coconut oil’s heat capacity and thermal conductivity as functions of temperature and used the measured properties to evaluate the feasibility of coconut oil for thermal buffering and passive heating of a residential-scale greenhouse.

scholarly journals A Novel Polymeric Adsorbent Embedded with Phase Change Materials (PCMs) Microcapsules: Synthesis and Application

Nanomaterials ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 736 ◽  
Author(s):  
Xingang Li ◽  
Lingyu Sun ◽  
Hong Sui ◽  
Lin He ◽  
Wei Yuan ◽  
...  
Keyword(s):  
Phase Change ◽  
Phase Change Materials ◽  
Gas Adsorption ◽  
High Specific Surface Area ◽  
Paraffin Wax ◽  
Heat Of Fusion ◽  
Scanning Calorimetry ◽  
Polymeric Adsorbent ◽  
Adsorption Column ◽  
Dominant Structure

The heat released during the industrial gas adsorption (e.g., volatile organic compounds (VOCs)) on adsorbents (e.g., activated carbon) would lead to the risks of fire and explosion in the adsorption column. Herein, a novel highly-porous Vinylbenzyl chloride-Divinylbenzene (VBC-DVB) polymeric adsorbent was synthesized with embedded microcapsules (Hypercrosslinked VBC-DVB Beads (HVPM)). These microcapsules have a polydivinylbenzene-phase change materials (DVB-PCMs) core-shell structure. Paraffin wax was used as PCM filling in the spherical capsule. This microcapsules-embedded polymeric adsorbent HVPM (Φ1.5–2.0 mm) is found to possess a high specific surface area (~665 m²/g) and micropore-dominant structure. It also has heat storage capability indicated by DSC (Differential Scanning Calorimetry) analysis (11.1 J/g heat of fusion between 35.0 and 48.2 °C) for the encapsulated paraffin wax. The lab adsorption tests proved the capabilities of HVPM in adsorbing VOCs (toluene, 0.21 g/g) and controlling the temperature inside the adsorption column during the dynamic adsorption process, in which the temperature rise was lowered by 62.5%, relatively.

Sign in / Sign up

Export Citation Format

Share Document