Molecular sieving of iso-butene from C<sub>4</sub> olefins with simultaneous high 1,3-butadiene and n-butene uptakes.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38472257.
- Also identified by DOI 10.1038/s41467-024-46607-y and PMC identifier 10933363.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Iso-butene (iso-C<sub>4</sub>H<sub>8</sub>) is an important raw material in chemical industry, whereas its efficient separation remains challenging due to similar molecular properties of C<sub>4</sub> olefins. The ideal adsorbent should possess simultaneous high uptakes for 1,3-butadiene (C<sub>4</sub>H<sub>6</sub>) and n-butene (n-C<sub>4</sub>H<sub>8</sub>) counterparts, endowing high efficiency for iso-C<sub>4</sub>H<sub>8</sub> separation in adsorption columns. Herein, a sulfate-pillared adsorbent, SOFOUR-DPDS-Ni (DPDS = 4,4'-dipyridyldisulfide), is reported for the efficient iso-C<sub>4</sub>H<sub>8</sub> separation from binary and ternary C<sub>4</sub> olefin mixtures. The rigidity in pore sizes and shapes of SOFOUR-DPDS-Ni exerts the molecular sieving of iso-C<sub>4</sub>H<sub>8</sub>, while exhibiting high C<sub>4</sub>H<sub>6</sub> and n-C<sub>4</sub>H<sub>8</sub> uptakes. The benchmark Henry's selectivity for C<sub>4</sub>H<sub>6</sub>/iso-C<sub>4</sub>H<sub>8</sub> (2321.8) and n-C<sub>4</sub>H<sub>8</sub>/iso-C<sub>4</sub>H<sub>8</sub> (233.5) outperforms most reported adsorbents. Computational simulations reveal the strong interactions for C<sub>4</sub>H<sub>6</sub> and n-C<sub>4</sub>H<sub>8</sub>. Furthermore, dynamic breakthrough experiments demonstrate the direct production of high-purity iso-C<sub>4</sub>H<sub>8</sub> (>99.9%) from C<sub>4</sub>H<sub>6</sub>/iso-C<sub>4</sub>H<sub>8</sub> (50/50, v/v), n-C<sub>4</sub>H<sub>8</sub>/iso-C<sub>4</sub>H<sub>8</sub> (50/50, v/v), and C<sub>4</sub>H<sub>6</sub>/n-C<sub>4</sub>H<sub>8</sub>/iso-C<sub>4</sub>H<sub>8</sub> (50/15/35, v/v/v) gas-mixtures.