Poster Presentation Royal Australian Chemical Institute National Congress 2026

Comparison of Carbon Dioxide Adsorption Kinetics in Batch and Flow-Through Systems for Functionalised MOFs (#501)

Hetansha A Boricha 1 , Marcello B Solomon 1 , Niket S Kaisare 2 , Deanna M D'Alessandro 1
  1. School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, New South Wales, Australia
  2. Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai, Tamil Nadu, India

Adsorbents that perform well for carbon dioxide (CO2) capture in laboratory conditions often fail to translate to industrial processes, largely due to limitations in adsorption kinetics.1 Adsorption kinetics describe the rate of CO₂ uptake and are critical for assessing performance under realistic operating conditions.2 They strongly influence contact time, regeneration requirements, and overall process economics of large-scale CO2 capture technologies.3 Faster kinetics can reduce cycle times, lower regeneration energy, and improve system efficiency. The quantification of adsorption kinetics, however, is challenging and strongly dependent on the material.4

Metal-Organic Frameworks (MOFs) possess high surface area and tuneable pores, making them robust CO₂ adsorbents. Functionalised MOFs are often considered due to their superior capacity and CO2 selectivity; however, functionalisation alters the pore chemistry, including steric hindrance,5 which may affect the adsorption kinetics. This study investigates the effect of functionalisation on adsorption kinetics using three different experimental approaches: (1) volumetric, (2) gravimetric, and (3) flow-through measurements. Batch adsorption experiments will be conducted using commercial instruments, while flow-through experiments will be conducted using an in-house-built dynamic breakthrough column. These approaches impose different transport conditions for the adsorbate, which may be sensitive to different controlling mass-transfer mechanisms.4 Comparing these approaches is essential to understand whether batch-derived kinetic parameters are transferable to flow-through systems and vice versa.

The kinetic data will be analysed using models reported in literature6,7 to identify the rate-limiting step, and assumptions will be consistent with experimental design. Comparisons will be made between pristine, functionalised MOF and batch, flow-through systems to evaluate how operating mode and materials influence the controlling mass-transfer mechanism. This enables us to assess the transferability of kinetics information between batch and flow-through systems and delineate the rate-limiting mechanisms.

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  2. Ruthven, D. M., Adsorption and Diffusion, 7, (2006), 1–43.
  3. Taddei, M. et al, Mol. Syst. Des. Eng., 6, (2021), 841–875.
  4. Wang, J. Y. et al., Adsorption, 27, (2021), 295–318.
  5. Molavi, H. et al, Microporous and Mesoporous Materials, 257, (2018), 193-201.
  6. Ruthven, D. M. et al. Adsorption, 27, (2021), 787–799.
  7. Kärger, J. et al. Pure Appl. Chem., 97, (2025), 1–89.