(144c) Microwave Swing Adsorption for Rapid Cycle CO2 Capture: Effect of Material and Process Parameters

In Thermal Swing Adsorption, typically a preheated gas is used to regenerate the adsorbent. Alternative, electrified, heating methods such as Joule heating (ESA), Induction heating and Microwave heating allow for a direct and contactless heating of the adsorbent, allowing independent control of the heating process and purge gas flow. Such electrified methods therefore allow to obtain the product at higher purity (less or no dilution by a purge gas) and, if available, can make use of renewable electricity, reducing the carbon footprint of the adsorption process. Disadvantages of the aforementioned methods include the need of specific materials that are compatible with the heating method and problems associated to scale up.

In the present work, we have studied the regeneration of adsorbents using microwave irradiation. Carbon based adsorbents were formulated under the form of extrudates or as structured adsorbent. A novel experimental setup, using a 915MHz Microwave generator, was built for cyclic adsorption-desorption experiments. The effect of adsorbent shape and dimensions on the efficiency of the heating process was evaluated. Temperature distribution and evolution was monitored as a function of microwave power, irradiation time and material properties. The efficiency of the conversion of microwave energy into heat generated within the adsorbent was determined. Adsorbent bed regeneration using Microwave Swing Adsorption was regeneration was evaluated for 2 important industrial applications.