(414a) Technological and Economic Analysis of Adsorption Processes for Direct Capture of CO2 From Air

Direct capture of CO₂ from air is a concept that can be potentially used to account for CO₂ emissions from mobile and disperse sources that are inaccessible to flue gas capture. Initially, we study equilibrium process models to determine the viability of adsorption-based air capture technologies using an amino-modified silica adsorbent, TRI-PE-MCM-41, and a structured monolithic contactor unit. Using the purity of CO₂ and annual product throughput as metrics for comparing process performance; we identify some of the operational parameters, adsorbent characteristics and sources of parasitic energy losses that have a significant effect on the performance of the process. Specifically, we will discuss a process with a daily throughput of ~1.1 tCO₂ at 88.5 %CO₂ purity using standard shipping container sized air capture modules. By accounting for the available sources of energy (low pressure steam and electricity) and geographic location, we obtain a net operating cost for air capture of CO₂ to be ~ $100/tCO₂. Recent results from more detailed adsorption models and experiments will also be presented. Finally, potential strategies for reducing the energy and monetary cost of these processes will be discussed. Our analysis supports continued work to establish the technological and economic feasibility of adsorption-based air capture.