Phase change materials (PCMs) can store thermal energy as latent heat through phase transitions. PCMs using the solid-liquid phase transition offer high 100–300 J g−1 enthalpy at constant temperature. However, pure compounds suffer from leakage, incongruent melting and crystallization, phase separation, and supercooling, which limit their heat storage capacity and reliability during multiple heating-cooling cycles. An appropriate approach to mitigating these drawbacks is the construction of composites as shape-stabilized phase change materials which retain their macroscopic solid shape even at temperatures above the melting point of the active heat storage compound. Shape-stabilized materials can be obtained by PCMs impregnation into porous matrices. Porous silica nanomaterials are promising matrices due to their high porosity and adsorption capacity, chemical and thermal stability and possibility of changing their structure through chemical synthesis. This review offers a first in-depth look at the various methods for obtaining composite PCMs using porous silica nanomaterials, their properties, and applications. The synthesis and properties of porous silica composites are presented based on the main classes of compounds which can act as heat storage materials (paraffins, fatty acids, polymers, small organic molecules, hydrated salts, molten salts and metals). The physico-chemical phenomena arising from the nanoconfinement of phase change materials into the silica pores are discussed from both theoretical and practical standpoints. The lessons learned so far in designing efficient composite PCMs using porous silica matrices are presented, as well as the future perspectives on improving the heat storage materials.

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New isothermal vapor−liquid equilibrium (VLE) and vapor−liquid−liquid equilibrium data for the carbon dioxide + 1-octanol system are reported at several temperatures, 303.15, 310.15, 315.15, 323.15, and 333.15 K, and pressures up to 145 bar. A staticanalytical method with phase sampling was used. The experimental results of this study are compared with literature data when available and discussed. The new and all available literature data for the carbon dioxide +1-octanol binary system are modeled with the cubic general equation of state and Peng−Robinson equations of state (EoS) with classical van der Waals mixing rules. The aforementioned EoS's were used to model the phase behavior of the carbon dioxide + 1-octanol binary system (critical curves, the three-phase equilibrium curve, isothermal VLE, and vapor−liquid−liquid equilibria), using a semipredictive approach. The results of the calculations are compared to the new data reported in this work and to all available literature data. The results show a satisfactory level of agreement between the models and the experimental data.