Capric-stearic acid mixture impregnated carbonized waste sugar beet pulp as leak-resistive composite phase change material with effective thermal conductivity and thermal energy storage performance

The present investigation aims to develop a potential composite phase change material (PCM) with leak-resistive and high thermal conductivity. Sugar beet pulp (CSBP) as an industrial waste was carbonized to produce a porous framework and used for solving leakage issue and boosting thermal conductivity of capric-stearic acid eutectic mixture (CSEM) used as PCM. FTIR and XRD results proved that the integration of CSEM and CSBP was carried out physically. The SEM analysis demonstrated that the CSEM was well uniformly impregnated within the pores of CSBP scaffold. DSC analysis revealed that the CSBP/CSEM (70 wt%) composite showed melting enthalpy and temperature as 117 J/g and 24 °C. The TGA measurements demonstrated that the produced composite was thermally stable. The incorporation of CSEM with CSBP leaded to a 79% increase in its thermal conductivity and this improvement was proved by comparing heating-cooling periods of CSEM and the composite PCM. The latent heat of the composite PCM was reduced less than 3% as its melting temperature was almost constant after 1000 thermal cycles. All findings of this work disclosed that the developed CSBP/CSEM as cost-effective and environmentally friendly composite PCM can be handled potential TES material for temperature controlling of buildings.