Amino-Functionalized Metal-Organic Frameworks Featuring Ultra-Strong Ethane Nano-Traps for Efficient C 2 H 6 /C 2 H 4 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 C 2 H 6 nano-trap, CuIn(3-ain) 4 is presented, which utilizes multiple guest-host interactions to efficiently capture C 2 H 6 molecules and separate mixtures of C 2 H 6 and C 2 H 4 . The ultra-strong C 2 H 6 nano-trap exhibits the high C 2 H 6 (2.38 mmol g -1 ) uptake at 6.25 kPa and 298 K and demonstrates a remarkable selectivity of 3.42 for C 2 H 6 /C 2 H 4 (10:90). Additionally, equimolar C 2 H 6 /C 2 H 4 exhibited a superior high separation potential ∆Q (2286 mmol L -1 ) at 298 K. Kinetic adsorption tests demonstrated that CuIn(3-ain) 4 has a high adsorption rate for C 2 H 6 , establishing it as a new benchmark material for the capture of C 2 H 6 and the separation of C 2 H 6 /C 2 H 4 . 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) 4 has been confirmed through breakthrough experiments for C 2 H 6 /C 2 H 4 gas mixtures.