Interaction-selective molecular sieving adsorbent for direct separation of ethylene from senary C<sub>2</sub>-C<sub>4</sub> olefin/paraffin mixture.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38245536.
- Also identified by DOI 10.1038/s41467-024-45004-9 and PMC identifier 10799885.
- 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
Olefin/paraffin separations are among the most energy-intensive processes in the petrochemical industry, with ethylene being the most widely consumed chemical feedstock. Adsorptive separation utilizing molecular sieving adsorbents can optimize energy efficiency, whereas the size-exclusive mechanism alone cannot achieve multiple olefin/paraffin sieving in a single adsorbent. Herein, an unprecedented sieving adsorbent, BFFOUR-Cu-dpds (BFFOUR = BF<sub>4</sub><sup>-</sup>, dpds = 4,4'-bipyridinedisulfide), is reported for simultaneous sieving of C<sub>2</sub>-C<sub>4</sub> olefins from their corresponding paraffins. The interlayer spaces can be selectively opened through stronger guest-host interactions induced by unsaturated C = C bonds in olefins, as opposed to saturated paraffins. In equimolar six-component breakthrough experiments (C<sub>2</sub>H<sub>4</sub>/C<sub>2</sub>H<sub>6</sub>/C<sub>3</sub>H<sub>6</sub>/C<sub>3</sub>H<sub>8</sub>/n-C<sub>4</sub>H<sub>8</sub>/n-C<sub>4</sub>H<sub>10</sub>), BFFOUR-Cu-dpds can simultaneously divide olefins from paraffins in the first column, while high-purity ethylene ( > 99.99%) can be directly obtained through the subsequent column using granular porous carbons. Moreover, gas-loaded single-crystal analysis, in-situ infrared spectroscopy measurements, and computational simulations demonstrate the accommodation patterns, interaction bonds, and energy pathways for olefin/paraffin separations.