決定論的横ずれ移動に着想を得た金属有機構造体による精密断面積ふるい分けによるC4オレフィンおよびパラフィン異性体の同時分離

The simultaneous separation of n/iso-C₄H₈ and n/iso-C₄H₁₀ mixtures presents a significant challenge due to the minimal difference in kinetic diameters (Δ < 0.2 Å) between n-butane and iso-butene. Inspired by the passive sorting mechanism of droplets via deterministic lateral displacement (DLD) in microfluidic architectures, we designed and synthesized a zinc-based metal-organic framework (CALF-20) featuring a canonical DLD array-like structure, wherein Zn' serves as periodic micropillar-like structural motifs. CALF-20 exhibits a critical pore cross-section precisely tailored to lie between the minimum cross-sectional areas of iso-C₄H₈ and n-C₄H₁₀, enabling simultaneous specific recognition of n-C₄H₈ and n-C₄H₁₀ while achieving complete steric exclusion of iso-C₄H₈ and iso-C₄H₁₀. The dual-ligand system in CALF-20 provides multiple cooperative binding sites for intelligent molecular recognition of linear C4 hydrocarbons, as further elucidated by theoretical calculations. Consequently, CALF-20 demonstrates high adsorption capacities of 2.7 and 2.5 mmol g^-1 for n-C₄H₈ and n-C₄H₁₀, respectively, while effectively excluding branched isomers. Dynamic breakthrough experiments validated the capability of CALF-20 to simultaneously produce high-purity (>99.999%) iso-C₄H₈ and n-C₄H₁₀ in a single operational step. Moreover, subsequent desorption yielded n-C₄H₈ and n-C₄H₁₀ with instantaneous purity exceeding 99.99%. This work establishes a DLD-inspired materials design paradigm, providing a groundbreaking and generalizable strategy for the efficient sieving separation of similarly challenging isomeric gas systems.