Efficient Propylene/Ethylene Separation in Highly Porous Metal-Organic Frameworks

Area of Science:

• Materials Science
• Chemical Engineering
• Separation Science

Background:

• Light olefins (C2-C4) are crucial petrochemical feedstocks.
• Efficient separation of light olefins is vital for various chemical production processes.
• Recent advancements focus on synthesizing light olefins from methanol or syngas, increasing the need for effective separation techniques.

Purpose of the Study:

• To investigate the adsorption and separation performance of novel Fe2M-L metal-organic frameworks (MOFs) for light olefins.
• To compare the efficacy of Fe2M-L MOFs against established materials like ZIF-8, MIL-101(Cr), HKUST-1, and activated carbon for C3H6/C2H4 separation.
• To evaluate the adsorption capacities, selectivities, and desorption dynamics of the studied materials.

Main Methods:

• Single-component gas adsorption experiments for ethylene (C2H4) and propylene (C3H6).
• Binary gas breakthrough experiments using a C3H6/C2H4 (1:9) mixture.
• Adsorption heat measurements for C2H4 and C3H6 on selected MOFs.
• Comparative analysis of adsorption and desorption kinetics.

Main Results:

• Fe2M-L, HKUST-1, and activated carbon exhibited higher C3H6 adsorption capacities compared to MIL-101(Cr) and ZIF-8.
• HKUST-1 and activated carbon demonstrated good C3H6/C2H4 adsorption selectivity.
• All tested adsorbents selectively adsorbed C3H6 from the mixture, yielding purified C2H4.
• Fe2M-L MOFs displayed faster C3H6 and C2H4 desorption rates, indicating lower regeneration energy requirements.

Conclusions:

• Fe2M-L MOFs are highly promising for selective C3H6/C2H4 separation.
• These MOFs offer efficient separation with a potential for reduced energy consumption in regeneration.
• The study highlights the potential of tailored MOFs in advancing petrochemical separation technologies.