Robust Two-Dimensional Hydrogen-Bonded Organic Framework for Efficient Separation of C1–C3 Alkanes

Abstract

Separating natural gas to obtain high-quality C1−C3 alkanes is an imperative process for supplying clean energy sources and high valued petrochemical feedstocks. However, developing adsorbents which can efficiently distinguish CH 4 , C 2 H 6 , and C 3 H 8 molecules remains challenging. We herein report an ultra-stable layered hydrogen-bonded framework (HOF-NBDA), which features differential affinities and adsorption capacities for CH 4 , C 2 H 6 , and C 3 H 8 molecules, respectively. Breakthrough experiments on ternary component gas mixture show that HOF-NBDA can achieve efficient separation of CH 4 /C 2 H 6 /C 3 H 8 (v/v/v, 85/7.5/7.5). More importantly, HOF-NBDA can realize efficient C 3 H 8 recovery from ternary CH 4 /C 2 H 6 /C 3 H 8 gas mixture. After one cycle of breakthrough, 70.9 L•kg −1 of high-purity (≥ 99.95%) CH 4 and 54.2 L•kg −1 of C 3 H 8 (purity ≥99.5%) could be obtained. Furthermore, excellent separation performance under different flow rates, temperatures, and humidities could endow HOF-NBDA an ideal adsorbent for the future natural gas purification.