Question

I have CO2 trapped in my activated carbon. What would be the most environmentally sustainable way to release it? I have heard of PSA (Pressure Swing Adsorption), which works when the adsorbent is subjected to a high-pressure environment, allowing it to adsorb CO2. Then, the pressure is reduced, causing the CO2 to desorb from the adsorbent and collect as a concentrated stream. But can that even work on activated carbon? Or is my best bet a temperature swing system (TSS), which requires lots of heat?

Answer 1

Pressure Swing Adsorption is an environmentally sustainable method to release CO2 from activated carbon, working effectively to adsorb and then desorb CO2 when pressure is altered. It aligns with carbon capture and sequestration strategies, and is preferable to Temperature Swing Systems which require more energy.

Step-by-step explanation:

The environmentally sustainable way to release CO2 trapped in activated carbon can be achieved through Pressure Swing Adsorption (PSA) or Temperature Swing System (TSS).

PSA is a viable technique where adsorption occurs at high pressure, and reducing the pressure allows for the CO2 to desorb and be collected. This process can indeed work on activated carbon, which is a commonly used adsorbent due to its efficacy in trapping gases, including CO2.

Furthermore, its use is considered environmentally friendly as activated carbon is nontoxic, inexpensive, and not a pollutant. CO2 recovery after PSD is relatively straightforward and sustainable, aligning with carbon capture and sequestration (CCS) strategies that aim to prevent CO2 emissions from reaching the atmosphere.

In the context of CCS, captured CO2 can be permanently stored underground in sealed porous rock formations. While TSS also works for releasing CO2, it requires substantial heat which may not be as environmentally sustainable as PSA. Thus for environmental sustainability, PSA is typically preferable over TSS when dealing with activated carbon.