Electrospun Fibrous Carbon Molecular Sieve Membrane for the Separation of Aromatics and Cyclic Aliphatics

The separation of aromatic compounds from cyclic aliphatics has drawn decades of attention from researchers. Adsorption-based separation, an energy-saving recovery technology, can be efficiently carried out on various adsorbents. Developing cost-effective adsorbents with good selectivity and batch preparation capability is an inevitable trend. Carbon molecular sieves (CMSs) are promising, but controlling the pore size distribution is a major limitation. In this work, a series of phenolic resin-based fibrous CMSs with a concentrated distribution of ultramicropores and conjugated sp2 carbon structures was synthesized by regulating electrospinning and heat treatment. Experimental and computational studies indicate that SCF2-1000 exhibits an adsorption amount ratio of 6.8 in static adsorption, comparable to those of reported framework materials and zeolites. In equimolar benzene/cyclohexane breakthrough experiments, it achieves a high adsorption amount ratio of 11.4 and a long separation window of 2000 min g-1. FCF-1H demonstrates a dynamic adsorption selectivity factor of 30.14 and a long separation window of 8300 min g-1 in a 1:9 toluene/methylcyclohexane separation experiment. The short-range and concentrated ultramicropores allow rapid, selective adsorption and easy regeneration without decline. This work offers a feasible pathway toward separating and purifying mixed gases containing aromatics and their hydrogenation products in industrial processes.