Preparation and properties of phase change energy storage building materials based on capric acid–octadecanol/fly ash–diatomite

Inorganic porous material is usually a good adsorption carrier serving for storage of solid–liquid phase change materials. As one of the largest types of industrial waste resource, reutilization of fly ash (FA) is an important way to protect environment, save energy and reduce emissions. In this study, a novel shape-stabilized phase change material (SSPCM) composed of capric acid and octadecanol/fly ash–diatomite (CA–OD/FA–DME) was prepared via vacuum adsorption method, and the appropriate mass ratio of CA–OD/FA–DME is 30:40:30 by diffusion–exudation circle experiments from the perspective of energy storage. The structure and thermal properties of the SSPCM were characterized and investigated by scanning electronic microscope (SEM), Fourier transformation infrared spectroscope (FTIR), X-ray diffraction (XRD), differential scanning calorimeter (DSC) and thermal gravimetric analyzer (TG). A series of experiments indicate that the prepared SSPCM has excellent thermal properties, thermal stability and thermal cycling stability. The energy storage wallboard (ESW) prepared by SSPCM can adjust indoor temperature and humidity effectively, and its data reveal application potential in building energy conservation and thermal recovery.