Isotherm, Kinetic, Process Modeling, and Techno-Economic Analysis of a Diamine-Appended Metal–Organic Framework for CO₂ Capture Using Fixed Bed Contactors

Abstract

Diamine-appended metal-organic frameworks exhibiting step-shaped CO2 adsorption are exceptional candidates for energy-efficient carbon capture. However, there are few studies examining their performance in real-world capture scenarios, in part due to the challenge inherent in modeling their CO2 uptake behavior. Here, we develop a dual-site Sips model to fit experimental CO2 adsorption data for dmpn-Mg2(dobpdc) (dmpn = 2,2-dimethyl-1,3-diaminopropane; dobpdc 4-= 4,4′-dioxidobiphenyl-3,3′-dicarboxylate) and develop a linear driving force model for the adsorption kinetics based on available experimental data. These models are used to develop a dynamic, fixed bed, non-isothermal contactor model using shaped particles of the material, which is validated with experimental breakthrough data. We also examine the effects of the high heat of adsorption of the material on CO2 uptake performance and find that heat removal is essential to maximize capture performance. We finally investigate "basic" (no bed cooling during adsorption) and "modified" (bed cooling during adsorption) temperature swing adsorption (TSA) processes using dmpn-Mg2(dobpdc) and their process economics are compared to a state-of-the-art monoethanolamine (MEA) capture system, with and without heat recovery. In the absence of heat recovery, the adsorbent systems are more costly than established technology. However, with 85% heat recovery, both adsorbent-based TSA processes are projected to cost less than the MEA system. This work highlights that thermal management is vital for implementation of dmpn-Mg2(dobpdc) as a viable CO2 capture technology. Investigation of other contactor technologies that can provide unique ways to manage system heat represent promising future areas of study.

Solid with infused reactive liquid (SWIRL): A novel liquid-based separation approach for effective CO 2 capture

“…Alternatively, amine-appended MOFs have shown notable promise for CO 2 capture. However, the path to commercialization of amine-appended MOFs is still evolving; these materials have poor thermal conductivity that requires substantial heat management in the adsorption bed ( 34 ) with uncertain material scale-up costs ( 35 ).…”

Research progress in metal–organic frameworks (MOFs) in CO2capture from post-combustion coal-fired flue gas: characteristics, preparation, modification and applications

“…Ntouros et al 130 adopted the LCA to investigate and evaluate the five synthetic routes for the production of ZIF-8 and found that deionized water as a solvent was more environmentally friendly than DMF and methanol. Hughes et al 131 investigated “basic” (no bed cooling during adsorption) and “modified” (bed cooling during adsorption) temperature swing adsorption (TSA) processes using dmpn-Mg 2 (dobpdc), respectively, and compared their process economics to the most advanced MEA capture systems. This showed that both sorbent-based TSA processes were expected to cost less than the MEA systems due to 85% heat recovery.…”

Scalable Formation of Diamine-Appended Metal–Organic Framework Hollow Fiber Sorbents for Postcombustion CO2 Capture

“…Moreover, in the special case of 2-ampd-appended-Mg 2 (dobpdc), the nonisothermal operation typically associated with packed beds increases the cost of the separation process. 19 Indeed, active thermal management (i.e., cooling during adsorption) has been identified as a critical aspect in the development of sorbents with type V isotherms. 19 To develop amine-functionalized MOFs for future implementation and commercialization, an alternative approach is needed.…”