Industrially-Driven Ultramicroporous Physisorbent with a Trifecta of Customized Functions for Upgrading C2H2/CO2 Separation Performance

Abstract

Targeting an adsorption-based strategy to achieve effective C₂H₂ purification while synchronously upgrading CO₂ effluent from C₂H₂/CO₂ mixtures is a daunting task given their similar physical natures. Herein, an ultramicroporous network with a trifecta of customized functions that can realize efficient C₂H₂/CO₂ separation is reported. Static and kinetic adsorption tests have cooperatively illustrated the potential separation performance. Column breakthrough tests confirm effective C₂H₂ purification at 298 K, yielding the desired C₂H₂ purity of 99.9–99.98% and a separation factor of 19.1 for equimolar C₂H₂/CO₂. Notably, food-grade CO₂ effluent with a higher purity of ≥99.95% can also be collected. Further, shaped 1a/PAN (PAN = polyacrylonitrile) nanofiber is formed by using an appealing net-fishing-inspired electrospinning (NFIE) strategy to accelerate the diffusion process of guests, as revealed by breakthrough tests. In situ high-resolution synchrotron X-ray diffraction (HRSXRD), simulations, etc. have explicitly unraveled the potential adsorption mechanism. Notably, the structurally stable 1a can be readily synthesized on a kilogram scale using cost-effective raw material (merely $320.3 kg⁻¹), which is of significant importance for industrial applications.