Robust Anion-Pillared Ultramicroporous Material for C₂H₂/C₂H₄ Separation with High C₂H₂ Uptake and Selectivity

Area of Science:

• Materials Science
• Chemical Engineering
• Separation Science

Background:

• Ethylene purification is critical for industrial applications.
• Separating trace acetylene from ethylene is a significant challenge.
• Existing methods often lack efficiency and selectivity.

Purpose of the Study:

• To develop a robust adsorbent for selective acetylene removal from ethylene.
• To achieve high acetylene adsorption capacity and ethylene/acetylene separation selectivity.
• To demonstrate the adsorbent's performance in industrial-relevant conditions.

Main Methods:

• Synthesis of a novel adsorbent, FJI-W88, incorporating SiF₆^2-.
• Characterization of FJI-W88's adsorption properties using acetylene/ethylene mixtures.
• Evaluation of selectivity using Ideal Adsorbed Solution Theory (IAST).
• Column breakthrough experiments to assess purification efficiency.

Main Results:

• FJI-W88 exhibits ultrahigh acetylene uptake (2.80 mmol g^-1 at 0.01 bar).
• Exceptional acetylene/ethylene selectivity (IAST selectivity of 698 for a 1/99 mixture).
• Achieved high purity ethylene (≥99.95%) with high yield (230.0 mol kg^-1).
• Stable performance under high temperature and humidity.

Conclusions:

• FJI-W88 is a highly effective adsorbent for acetylene removal from ethylene.
• The adsorbent demonstrates excellent selectivity and capacity for efficient ethylene purification.
• FJI-W88 shows robustness for practical industrial applications.