Amino-Functionalized Metal-Organic Frameworks Featuring Ultra-Strong Ethane Nano-Traps for Efficient CH/CH Separation.

Developing high-performance porous materials to separate ethane from ethylene is an important but challenging task in the chemical industry, given their similar sizes and physicochemical properties. Herein, a new type of ultra-strong CH nano-trap, CuIn(3-ain) is presented, which utilizes multiple guest-host interactions to efficiently capture CH molecules and separate mixtures of CH and CH. The ultra-strong CH nano-trap exhibits the high CH (2.38 mmol g) uptake at 6.25 kPa and 298 K and demonstrates a remarkable selectivity of 3.42 for CH/CH (10:90). Additionally, equimolar CH/CH exhibited a superior high separation potential ∆Q (2286 mmol L) at 298 K. Kinetic adsorption tests demonstrated that CuIn(3-ain) has a high adsorption rate for CH, establishing it as a new benchmark material for the capture of CH and the separation of CH/CH. Notably, this exceptional performance is maintained even at a higher temperature of 333 K, a phenomenon not observed before. Theoretical simulations and single-crystal X-ray diffraction provide critical insights into how selective adsorption properties can be tuned by manipulating pore dimensions and geometry. The excellent separation performance of CuIn(3-ain) has been confirmed through breakthrough experiments for CH/CH gas mixtures.