Advanced PCT Measurements with Cryogenic Cooler Capabilities
The National Renewable Energy Laboratory (NREL) has a modified PCT Pro system with capabilities of hydrogen pressures up to 200 bar and a controlled temperature range from 40 to 350 K (other gases including CH4 are possible). This system allows for Qst calculations for multiple binding sites.
PCT Analysis. NREL has all the requisite equipment, capabilities, and expertise to continue to offer specialized analysis of materials specifically for their hydrogen and methane gravimetric and volumetric capacities. We have optimized techniques that enable rapid throughput with accurate and precise measurements on samples from 200 mg to grams. We have modified a Sieverts instrument, a PCTPro 2000, to allow for variable sample temperatures for PCT measurements at arbitrary temperatures from ~50 K to 350 K and pressures up to 160 bar. This capability enables the determination of the isosteric heats of adsorption.
Figure 1. Modified PCT Pro system
Figure 2. The isotherms obtained and used for the isosteric heat calculations on the new variable temperature PCT apparatus (Source: NREL)