Cu(I)-COF facilitated transport membranes for aromatics-alkanes separation

Separating aromatic and aliphatic hydrocarbons can produce high-quality cracking feedstocks and recover value-added aromatic products. Covalent organic framework (COF) may find promising application owing to its exceptional structures and functionalities. In this study, Cu(I)-COF was designed and integrated into Pebax matrix to fabricate facilitated transport membranes. The immobilization of Cu(I) ions onto the COF framework effectively mitigates leaching. Additionally, the COF building blocks provides a stable electron cloud environment for Cu(I), ensuring long-term stability for over 6 months. The vertical channels in the COF afford rapid mass transfer, and the uniformly distributed Cu(I) enhances toluene affinity, thereby intensifying the transfer of toluene. For a 50 wt% toluene/n-heptane mixture, the Cu 3 L 3 -Pa-Pebax-2 membrane demonstrated a permeation flux of 1100 g·m −2 ·h −1 and a separation factor of 5.44. This study provides a new example for the application of multifunctional organic framework materials to fabricate facilitated transport membranes.