Evolution of the energetic characteristics of {silicalite-1 + water} repulsive clathrates in a wide temperature range

Abstract

Recently {lyophobic porous powders + liquid} systems were proposed to be used for nontraditional energy storage and conversion purposes. This article reports the experimental study of the mechanical behavior, within the pressure–volume (PV) diagram, of the {hydrophobic silicalite-1 + water} system in the temperature range 10–80 °C. Repeated recordings of PV-isotherms and thermal effects of the repulsive clathrate during successive compression–decompression runs were performed using scanning transitiometry. An unexpected steady decline in the intrusion–extrusion pressure and volume of embedded water was found during the forced (repeated) intrusion of water into the pores of silicalite-1 and its spontaneous extrusion at constant temperature. A discussion of possible reasons of unconventional behavior of these heterogeneous systems as well as a thermodynamic analysis is presented.