Departmental Seminar - Dr. Alexander Lowe

Dr. Alexander R Lowe from the University of Silesia in Katowice, Poland will give a seminar entitled “Pressure Scanning Calorimetry as a Valuable Tool to Investigate the Heat of Liquid Confinement into Mesoporous Materials” on May 29 at 1:30 PM in the Link Room (MACN 101). 

 

Dr. Lowe completed his MSc it the Tremaine Group here at the University of Guelph before completing his PhD and is now at the University of Silesia in Poland doing a unique form of calorimetry on fluids for energy storage in porous media.

 

Abstract: Applying pressure rather than heat is an interesting mode for observing thermal effects in liquid systems. Different techniques are used to apply changes in pressure, either by rapidly changing the pressure within seconds (known as pressure perturbation calorimetry) or by steadily increasing the pressure over time (known as pressure scanning calorimetry, where it maintains a state of thermodynamic equilibrium). Scanning transitiometry applies the pressure-scanning mode in combination with a differential heat-flux calorimetric detector to measure the heat associated with the compression and expansion of a liquid. This technique has been used to investigate the heat effects of liquid intrusion and extrusion into and from the pores of hydrophobic mesoporous and microporous materials. This process can occur over a wide pressure range, depending on the porous matrix. The reverse process occurs at lower pressure through extrusion, releasing the energy stored in the intruded liquid. This cyclic behavior of liquid intrusion and extrusion can be exploited for a variety of mechanical energy storage and dissipation applications, ranging from springs (with little hysteresis) to shock absorbers (with moderate hysteresis) and bumpers (with large hysteresis and complete energy dissipation). The physical properties of these cycles can be affected by changes in solution composition, solid particle size, and surface characteristics. This presentation will demonstrate how scanning transitiometry reveals the thermal effects of intrusion and extrusion in a variety of hydrophobic mesoporous materials, including pure silica-based zeolites, grafted porous materials and metal–organic frameworks (ZIF-8).

Coffee and Timbits at 1:15 PM