Rheological study on xylitol crystallization for its use as phase change material: analytical and statistical analysis

Navarro, Miguel (Universidad de Zaragoza) ; Gracia, Zeus (Universidad de Zaragoza) ; Asín, Jesús (Universidad de Zaragoza) ; Lázaro, Ana (Universidad de Zaragoza) ; Martí, Marta ; Delgado, Mónica (Universidad de Zaragoza)

Resumen: In a global context in which decarbonization of society is wanted through the use of renewable sources, energy storage plays a fundamental role. Among the different forms of energy storage that exists, this work focuses on latent heat energy storage (LHTES) for medium-low temperatures, between 70 °C and 120 °C. Xylitol, a sugar-alcohol, is a promising phase change material (PCM) due to its low cost, low corrosivity, high latent heat (240 J/g) and a melting temperature of 92 °C. However, its use as PCM is hindered by a high degree of supercooling and a low crystallization rate. To address these challenges, this work used a seeding and shearing technique to trigger crystallization. Rheological experiments were performed to monitor viscosity changes during crystallization, in order to study the crystallization induction time. The systematic analysis included the effects of temperature (70–90 °C), shear rate(1-100s−1), and seed crystal size (300–400 μm and 600–700 μm). Key results show that temperature is the most dominant factor. The shortest induction time at 70 °C was found at 10s, increasing to 1500s at 90 °C. Increasing seed size and reducing the rheometer gap also shortened induction times, while shear rate had minimal influence, likely due to non-uniform shear during the test. For practical applications, operating at 80 °C is recommended to balance induction time and energy loss due to supercooling. Optimizing shear-triggered mechanism, such as stirred tanks designs, can improve crystallization controllability.

Idioma: Inglés

DOI: 10.1016/j.solmat.2025.113803

Año: 2025

Publicado en: SOLAR ENERGY MATERIALS AND SOLAR CELLS 292 (2025), 113803 [9 pp.]
ISSN: 0927-0248

Financiación: info:eu-repo/grantAgreement/ES/AEI/PID2020-115500RB-I00
Financiación: info:eu-repo/grantAgreement/ES/AEI/PID2023-148958OB-C21
Financiación: info:eu-repo/grantAgreement/ES/AEI/RYC2023-044207-I
Financiación: info:eu-repo/grantAgreement/ES/DGA/E46-23R
Financiación: info:eu-repo/grantAgreement/ES/DGA/T55-20R
Financiación: info:eu-repo/grantAgreement/ES/MICINN PRE2021-097131
Financiación: info:eu-repo/grantAgreement/EUR/MICINN/TED2021-131061B–C31
Financiación: info:eu-repo/grantAgreement/ES/AEI/RED2022-134202-T

Tipo y forma: Article (Published version)

Área (Departamento): Área Estadís. Investig. Opera. (Dpto. Métodos Estadísticos)
Área (Departamento): Área Máquinas y Motores Térmi. (Dpto. Ingeniería Mecánica)