A Layered Hydrogen-Bonded Organic Framework with C₃H₆-Preferred Pores for Efficient One-Step Purification of Methanol-to-Olefins (MTO) Products

Abstract

Separation of methanol-to-olefins (MTO) products to obtain high-purity C 2 H 4 and C 3 H 6 is of great importance, since it provides an alternative process for such important industrial raw materials. However, developing adsorbents with high C 2 H 4 /C 3 H 6 selectivity and productivity remains challenging. Herein, we report an ultrastable layered hydrogen-bonded framework (HOF-NBDA), which features C 3 H 6 preferred pore with multiple interlaminar interactions with C 3 H 6 . It delivers an ultrahigh C 3 H 6 uptake (3.6 mmol g −1 ) at 10 kPa, while absorbs only 0.3 mmol g −1 C 2 H 4 and shows a high C 2 H 4 /C 3 H 6 selectivity (11.1). Experimental breakthroughs show that HOF-NBDA can efficiently separate C 3 H 6 /C 2 H 4 (50/ 50, v/v) at different flow rates, temperatures, as well as relative humidities and provides a high C 2 H 4 productivity (5.7 mol kg −1 , purity ≥99.95%). Meanwhile, 4.5 mol kg −1 C 3 H 6 (purity ≥99.5%) can also be collected during the desorption process. Additionally, thanks to ultrahigh stability, good scalability, and easy regeneration, HOF-NBDA is considered as a promising material for one-step energy-efficient separation of MTO products.