Cellulose-Based Hybrid Composites Enabled by Metal Organic Frameworks for CO2 Capture: The Effect of Cellulosic Substrate.

A comparative study of two cellulosic materials i.e., cotton fabrics and bacterial cellulose nanofibers (NBC), is reported as substrates for metal organic frameworks (MOF-199), to prepare micro and nanocomposites of cellulose@MOF-199 for CO₂ capture. The CO₂ uptake performance was investigated using gravimetric adsorption and desorption kinetics. NBC was an efficient substrate with full coverage and uniform distribution of MOF crystals observed in NBC@MOF-199 nanocomposite. The surface area for NBC@MOF-199 and Cotton@MOF-199 were 553.4 m² g⁻¹ and 168.9 m² g⁻¹, respectively. NBC@MOF-199 showed a high adsorption capacity (2.9 mmol g⁻¹) at ambient temperature and pressure, followed by Cotton@MOF-199 (1.2 mmol g⁻¹). The kinetic studies revealed that the adsorption process is controlled by film diffusion at lower temperatures, and by sorption to active sites at higher temperatures. The estimated thermodynamic parameters represent a spontaneous adsorption with low activation energies of adsorption/desorption, promising a fast adsorption and facilitated regeneration adsorbent system with minimum energy costs. [ABSTRACT FROM AUTHOR]