Incorporation of Cu(I) Sites into Zeolite via a Controllable Reduction Strategy for Ethylene/Ethane Separation

The development of effective adsorbents for efficient separation of ethylene (C2H4) and ethane (C2H6) is crucial for the petrochemical sector, yet this is still difficult because of their comparable molecule sizes and physical characteristics. Cu(I) could generate pi-complexes with molecules containing unsaturated bonds, enabling Cu(I)-based adsorbents to selectively and efficiently separate C2H4 from C2H6. However, the traditional autoreduction method typically requires extreme temperatures (>= 700 degrees C) to convert Cu(II) to Cu(I), leading to high energy consumption. In this study, we present a controllable reduction strategy that employs methanol as the reductant to efficiently and controllably convert Cu(II) in Y zeolite to Cu(I). With this approach, Cu(I) sites could be formed under a modest temperature of 200 degrees C. Due to the generated Cu(I) sites, the C2H4 uptake for Cu(I)-Y reaches 3.85 mmol/g and the C2H4/C2H6 selectivity is 19.21. This performance surpasses those of benchmark adsorbents, including CuX (2.31 mmol/g, 1.06), Cu(I)-doped mesoporous carbon MC-Cu-2 (1.94 mmol/g, 4.00), and Cu+@MIL-101 (2.46 mmol/g, 14.00).