Compatibility of Phase Change Materials and Metals: Experimental Evaluation Based on the Corrosion Rate

The construction and maintenance of building stock is responsible for approximately 36% of all CO<sub>2</sub> emissions in the European Union. One of the possibilities of how to achieve high energy-efficient and decarbonized building stock is the integration of renewable energy sources (...

Full description

Bibliographic Details
Main Authors: Milan Ostrý, Sylva Bantová, Karel Struhala
Format: Article
Language:English
Published: MDPI AG 2020-06-01
Series:Molecules
Subjects:
Online Access:https://www.mdpi.com/1420-3049/25/12/2823
_version_ 1827714693412683776
author Milan Ostrý
Sylva Bantová
Karel Struhala
author_facet Milan Ostrý
Sylva Bantová
Karel Struhala
author_sort Milan Ostrý
collection DOAJ
description The construction and maintenance of building stock is responsible for approximately 36% of all CO<sub>2</sub> emissions in the European Union. One of the possibilities of how to achieve high energy-efficient and decarbonized building stock is the integration of renewable energy sources (RES) in building energy systems that contain efficient energy storage capacity. Phase Change Materials (PCMs) are latent heat storage media with a high potential of integration in building structures and technical systems. Their solid-liquid transition is specifically utilized for thermal energy storage in building applications. The typically quite old example is the use of ice that serves as long-term storage of cold. Large pieces of ice cut in winter were stored in heavily insulated spaces and prepared for cooling of food or beverages in summer. In the contemporary use of the principle, the PCMs for building applications and tested in this study must have a melting range close to the desired temperature in the occupied rooms. As the PCMs need to be encapsulated, several types of metal containers have been developed and tested for their thermal conductivity and resistance to mechanical damage, which enhances the performance of these so-called latent heat thermal energy storage (LHTES) systems. Long-term compatibility of metals with PCMs depends, i.e., on the elimination of an undesirable interaction between the metal and the specific PCM. Heat storage medium must be reliably sealed in a metal container, especially if the LHTES is integrated into systems where PCM leaks can negatively affect human health (e.g., domestic hot water tanks). The aim of this study is to evaluate the interactions between the selected commercially available organic (Linpar 17 and 1820) and inorganic (Rubitherm SP22 and SP25) PCMs and metals widely used for PCM encapsulation (aluminum, brass, carbon steel, and copper). The evaluation is based on the calculation of the corrosion rate (CR), and the gravimetric method is used for the determination of the weight variations of the metal samples. The results show good compatibility for all metals with organic PCMs, which is demonstrated by a mass loss as low as 2.1 mg in case of carbon steel immersed in Linpar 1820 for 12 weeks. The exposure of metals to organic PCMs also did not cause any visual changes on the surface except for darker stains, and tarnishing occurred on the copper samples. More pronounced changes were observed in metal samples immersed in inorganic PCMs. The highest CR values were calculated for carbon steel exposed to inorganic PCM Rubitherm SP25 (up to 13.897 mg·cm<sup>−2</sup>·year<sup>−1</sup>). The conclusion of the study is that aluminum is the most suitable container material for the tested PCMs as it shows the lowest mass loss and minimal visual changes on the surface after prolonged exposure to the selected PCMs.
first_indexed 2024-03-10T19:03:08Z
format Article
id doaj.art-5514ee8892424d8a9ffe6695214743f4
institution Directory Open Access Journal
issn 1420-3049
language English
last_indexed 2024-03-10T19:03:08Z
publishDate 2020-06-01
publisher MDPI AG
record_format Article
series Molecules
spelling doaj.art-5514ee8892424d8a9ffe6695214743f42023-11-20T04:16:36ZengMDPI AGMolecules1420-30492020-06-012512282310.3390/molecules25122823Compatibility of Phase Change Materials and Metals: Experimental Evaluation Based on the Corrosion RateMilan Ostrý0Sylva Bantová1Karel Struhala2Brno University of Technology, Faculty of Civil Engineering, 602 00 Brno, Czech RepublicBrno University of Technology, Faculty of Civil Engineering, 602 00 Brno, Czech RepublicBrno University of Technology, Faculty of Civil Engineering, 602 00 Brno, Czech RepublicThe construction and maintenance of building stock is responsible for approximately 36% of all CO<sub>2</sub> emissions in the European Union. One of the possibilities of how to achieve high energy-efficient and decarbonized building stock is the integration of renewable energy sources (RES) in building energy systems that contain efficient energy storage capacity. Phase Change Materials (PCMs) are latent heat storage media with a high potential of integration in building structures and technical systems. Their solid-liquid transition is specifically utilized for thermal energy storage in building applications. The typically quite old example is the use of ice that serves as long-term storage of cold. Large pieces of ice cut in winter were stored in heavily insulated spaces and prepared for cooling of food or beverages in summer. In the contemporary use of the principle, the PCMs for building applications and tested in this study must have a melting range close to the desired temperature in the occupied rooms. As the PCMs need to be encapsulated, several types of metal containers have been developed and tested for their thermal conductivity and resistance to mechanical damage, which enhances the performance of these so-called latent heat thermal energy storage (LHTES) systems. Long-term compatibility of metals with PCMs depends, i.e., on the elimination of an undesirable interaction between the metal and the specific PCM. Heat storage medium must be reliably sealed in a metal container, especially if the LHTES is integrated into systems where PCM leaks can negatively affect human health (e.g., domestic hot water tanks). The aim of this study is to evaluate the interactions between the selected commercially available organic (Linpar 17 and 1820) and inorganic (Rubitherm SP22 and SP25) PCMs and metals widely used for PCM encapsulation (aluminum, brass, carbon steel, and copper). The evaluation is based on the calculation of the corrosion rate (CR), and the gravimetric method is used for the determination of the weight variations of the metal samples. The results show good compatibility for all metals with organic PCMs, which is demonstrated by a mass loss as low as 2.1 mg in case of carbon steel immersed in Linpar 1820 for 12 weeks. The exposure of metals to organic PCMs also did not cause any visual changes on the surface except for darker stains, and tarnishing occurred on the copper samples. More pronounced changes were observed in metal samples immersed in inorganic PCMs. The highest CR values were calculated for carbon steel exposed to inorganic PCM Rubitherm SP25 (up to 13.897 mg·cm<sup>−2</sup>·year<sup>−1</sup>). The conclusion of the study is that aluminum is the most suitable container material for the tested PCMs as it shows the lowest mass loss and minimal visual changes on the surface after prolonged exposure to the selected PCMs.https://www.mdpi.com/1420-3049/25/12/2823phase change materials (PCMs)metalscontainerlatent heat storagecorrosion
spellingShingle Milan Ostrý
Sylva Bantová
Karel Struhala
Compatibility of Phase Change Materials and Metals: Experimental Evaluation Based on the Corrosion Rate
Molecules
phase change materials (PCMs)
metals
container
latent heat storage
corrosion
title Compatibility of Phase Change Materials and Metals: Experimental Evaluation Based on the Corrosion Rate
title_full Compatibility of Phase Change Materials and Metals: Experimental Evaluation Based on the Corrosion Rate
title_fullStr Compatibility of Phase Change Materials and Metals: Experimental Evaluation Based on the Corrosion Rate
title_full_unstemmed Compatibility of Phase Change Materials and Metals: Experimental Evaluation Based on the Corrosion Rate
title_short Compatibility of Phase Change Materials and Metals: Experimental Evaluation Based on the Corrosion Rate
title_sort compatibility of phase change materials and metals experimental evaluation based on the corrosion rate
topic phase change materials (PCMs)
metals
container
latent heat storage
corrosion
url https://www.mdpi.com/1420-3049/25/12/2823
work_keys_str_mv AT milanostry compatibilityofphasechangematerialsandmetalsexperimentalevaluationbasedonthecorrosionrate
AT sylvabantova compatibilityofphasechangematerialsandmetalsexperimentalevaluationbasedonthecorrosionrate
AT karelstruhala compatibilityofphasechangematerialsandmetalsexperimentalevaluationbasedonthecorrosionrate