Researchers
test the separation potential of new materials using the time-lag, a.k.a.
constant volume, method that sets the standard in the field. A film sample approximately 2 cm in diameter
is sealed in a high-pressure cell in a temperature-controlled box. One surface
of the film, supported by a porous screen, contacts a container of known
volume. Gases at different pressures (0-50 bar) are introduced to the other
surface of the film. Gas penetrates into the film and moves through it, to the
known volume. The rate of pressure rise in this known volume is monitored by
computer and analyzed in real time, using software developed at KAUST, to
determine permeability. Gas arrives at the known volume after a time lag, or
delay, the length of which is used to estimate solubility of the gas in the
film material. The lab operates twelve
of these pure gas permeation instruments, which were constructed from scratch
by the Center’s first generation of students and staff using materials sourced
from America, Europe, and KSA.
