Direct production of o-xylene from six-component BTEXs using a channel-pore interconnected metal-organic framework

Abstract

Metal-organic frameworks (MOFs) with precisely controlled pore dimensions have greatly enriched the versatility of molecular sieving materials. Here, we report a channel-pore interconnected MOF (JNU-2) for direct production of o-xylene from six-component BTEXs (benzene, toluene, ethylbenzene, o-xylene, m-xylene, and p-xylene) in a single adsorption process. Individual adsorption measurements show complete exclusion of o-xylene and benchmark adsorption of other BTEXs. Competitive adsorption studies reveal record-high adsorption selectivity of other BTEXs over o-xylene. Vapor-phase breakthrough experiments verify its superior separation potential for sieving o-xylene from BTEXs. We further demonstrate o-xylene purification by simply soaking JNU-2 (10 g) in BTEXs (18 mL, 90% o-xylene) at room temperature, realizing an average of 15.2 mL of o-xylene (99.5%+ purity, 94% recovery) for 10 cycles. Considering its exceptional stability, JNU-2 may have great promise for energy-efficient o-xylene separation from BTEXs.