麻豆淫院

UNIST and Hanyang University researchers have developed a novel porous material capable of high-purity separation of xylene isomers at room temperature. This breakthrough promises to significantly reduce energy consumption and process complexity in petrochemical refining.

Their findings were in the online version of Angewandte Chemie International Edition.

Xylene, a key raw material used in plastic bottles, synthetic fibers, and fragrances, exists as three isomers鈥攐rtho-, meta-, and para-xylene鈥攅ach with distinct applications. These isomers, along with ethylbenzene, are typically produced as a mixture in petrochemical processes, requiring energy-intensive separation steps under high temperature and pressure.

The research team successfully developed a porous metal鈥搊rganic framework (MOF) that selectively captures and separates these isomers under ambient conditions.

Unlike conventional MOFs, which feature open channels on multiple sides, this innovative design has blocked side pores and open vertical channels. This structure was achieved by incorporating a large organic molecule called DABCO into a nickel-based framework.

This configuration functions as a molecular sieve: the bent shape of ortho-xylene is effectively filtered out at the entry point, while the elongated para-xylene and ethylbenzene molecules can pass through and be adsorbed within the internal pores.

This specially designed MOF demonstrated up to 268 times higher selectivity for ortho-xylene compared to existing materials, with performance maintained over multiple reuse cycles. Such high selectivity at room temperature represents a significant advancement over traditional high-temperature separation methods.

Professor Lah explained, "Our new material can spontaneously separate specific xylene isomers at ambient conditions, overcoming the limitations of high-temperature, high-pressure processes. This innovation could lead to more energy-efficient and environmentally friendly petrochemical separation techniques, contributing to sustainable industrial practices."

The research was conducted by Seonghwan Lee, Amitosh Sharma, and Jae Hyeok Lee, who served as first authors.