Hkust-1 Infused Woven Cotton Filter for Enhanced Adsorptive Removal of Toluene Vapor from Gaseous Streams

Abstract

The utility of metal-organic frameworks (MOFs) for air/gas purification against various targets like volatile organic compounds (VOCs) is well-known. The adsorption properties of fine powdery porous MOFs (e.g., HKUST-1) have commonly been investigated after being loaded in a packed-bed system, but such a platform can be subjected to a significant space velocity/pressure drop. To overcome such shortcomings, a new fibrous MOF-based woven fiber sorbent was prepared via in-situ growth of HKUST-1 crystals on woven cotton substrates (thickness ≈1mm, diameter = 4.3 cm) at five different mass ratios of infused MOFs (i.e., 2.4, 6.6, 9.5, 31.2, and 41.8% wt/wt). The adsorption efficacy of the five woven cotton filtration systems was studied in reference to the packed bed sorbent using 1 Pa toluene vapor at near-ambient conditions. The relative adsorption performance of toluene was related to the varying content of infused HKUST-1 (e.g., 41.8 > 31.2 > 9.5 > 6.6> 2.4% wt/wt) and the surface availability (m2 [g∙HKUST-1]−1) (e.g., 435< 552< 600< 731< 1009, respectively). This research offers valuable insights into the significance of morphological features of filtration systems for various environmental applications of MOFs (such as air purification by adsorption filtration systems).

Keywords: Adsorption, HKUST-1, ICF, gaseous toluene, kinetic analysis, performance comparison