Encapsulation of dodecane in gasification biochar for its prolonged thermal/shape stability, reliability, and ambient enthalpy storage

Abstract

Latent heat storage based on phase-changing materials (PCMs) is a promising technology for thermal energy storage because of its large heating enthalpy and isothermal phase-transition temperature. However, the practical applications of PCMs is highly restricted because of their intrinsically low thermal conductivity, which limits real-time energy storage/release, seepage during the phase-transition process, and expensive supporting materials. Therefore, the development of shape-stable composite PCMs by using renewable precursors, such as biomass, has received considerable research attention because of their low cost, environmental friendliness, and availability. In this study, waste biomass materials (food waste and wood waste) activated by KOH were pyrolyzed to produce biochar/biocarbon and subsequently used for organic PCM, dodecane, encapsulation. The obtained biochar exhibited a high specific surface area and pore size distribution. The biochar–dodecane composite (FWP) was designed by using a solvent-free facile vacuum impregnation method. The composite materials exhibited high leakage resistance, improved thermal stability, enhanced thermal conductivity, and improved PCM loading capacity (67.98%). FWP exhibited high latent heat retention of 87.7% after multiple thermal cycles and excellent chemical compatibility with composite constituents. Thus, biochar, derived from biowaste, with organic PCM can be effective in numerous thermal-regulation applications, including air conditioning, and further open avenue for converting waste-to-energy.