Enhancement of the Phase Transition Enthalpy of an Organic Phase Change Material Through the Use of Clinoptilolite

The article presents a novel, energy-efficient composite of clinoptilolite and an organic phase change material (PCM), exhibiting a greater heat storage capacity than would be expected based solely on the PCM content within the composite. The study included a structural and textural analysis of clinoptilolite powder as a fine-grained material, with particular emphasis on its properties and compatibility with paraffin-based phase change materials. The second stage of the research involved determining changes in the enthalpy of melting and solidification of the composites, as well as evaluating their ability to retain the liquid phase and confirming the absence of chemical reactions between individual composite components. The obtained results demonstrated an increase in the enthalpy of the composite by approximately 14% and 44% relative to the expected values for PCM contents of 50% and 40%, respectively. Furthermore, the approximate content of paraffin-based PCM in the clinoptilolite composite at which no leakage occurs during the melting process was determined. This work represents a new approach to the integration of porous materials and phase change materials, enabling the formation of energetically favorable structures that significantly enhance the effective thermal storage capacity of PCM-based composites.