Direct Ink 3D Printing of Porous Carbon Monoliths for Gas Separations

Area of Science:

• Materials Science
• Chemical Engineering
• Additive Manufacturing

Background:

• Additive manufacturing (3D printing) offers advanced fabrication of monolithic adsorbents with superior structural properties compared to traditional beads or pellets.
• Research on 3D printing of porous carbon adsorbents remains limited, despite the growing interest in advanced materials for gas separation and storage.

Purpose of the Study:

• To report the direct ink 3D printing of porous carbon monoliths.
• To characterize the structural and adsorption properties of the 3D printed porous carbon.
• To evaluate the gas separation performance and cyclic stability of the developed adsorbent.

Main Methods:

• Formulation of a printable ink using commercial activated carbon, poly(4-vinylphenol), Pluronic F127, and bentonite.
• Direct ink 3D printing using a modified commercial 3D printer.
• Post-printing carbonization and characterization of the porous carbon monolith.

Main Results:

• The 3D printed porous carbon exhibited a stable structure with a BET surface area of 400 m²/g and a total pore volume of 0.27 cm³/g.
• Gas adsorption isotherms for CO2, CH4, C2H6, N2, CO, and H2 were measured, and selectivities for key gas pairs were calculated using IAST.
• The adsorbent demonstrated excellent cyclic stability for CO2 adsorption and desorption over ten cycles without loss of working capacity.

Conclusions:

• Direct ink 3D printing is a viable method for fabricating porous carbon adsorbents with desirable structural and adsorption properties.
• The developed 3D printed porous carbon shows potential for applications in gas separation and carbon capture technologies.
• The material's stability and performance over multiple cycles highlight its practical applicability.