Thanks to infrared thermography, we have studied the mechanisms of CO2 capture
by solid adsorbents (CO2 capture via gas adsorption on various types of porous
substrates) to better understand the physico-chemical mechanisms that control
CO2-surface interactions. In order to develop in the future an efficient
process for post-combustion CO2 capture, it is necessary to quantify the energy
of adsorption of the gas on the adsorbent (exothermic process). The released heat (heat of
adsorption) is a key parameter for the choice of materials and for the design of capture
processes. Infrared thermography is used, at first approach, to detect the temperature
fields on a thin-layer of adsorbent during CO2 adsorption. An analytical heat
transfer model was developed to evaluate the adsorption heat flux and to estimate, via an
inverse technique, the heat of adsorption. The main originality of our method is to
estimate heat losses directly from the heat generated during the adsorption process. Then,
the estimated heat loss is taken for an a posteriori calculation of the adsorption heat
flux. Finally, the heat of adsorption may be estimated. The interest in using infrared
thermography is also its ability to quickly change the experimental setup, for example, to
switch from the adsorbent thin-layer to the adsorbent bed configuration. We present the
first results tempting to link the thin-layer data to the propagation speed of the thermal
front in a millifluidics adsorption bed, also observed by IR thermography.