Additive Manufacturing and Functionalization of Hollow Polypropylene Sorbents for Water Remediation

Area of Science:

• Materials Science
• Environmental Engineering
• Polymer Chemistry

Background:

• Growing demand for clean water necessitates advanced pollutant removal technologies.
• Organic micropollutants pose significant risks to water quality and ecosystem health.
• Current sorbent materials often lack sufficient surface area and tailored functionalities for efficient contaminant capture.

Purpose of the Study:

• To establish a method for additive manufacturing of functional polymer sorbents with hollow porous architectures.
• To enhance interactions with organic micropollutants through tailored material design and surface functionalization.
• To investigate the impact of structural features on pollutant adsorption efficiency and kinetics.

Main Methods:

• Utilized core-shell filaments (polypropylene shell, poly(acrylonitrile-co-butadiene-styrene) core) for 3D printing via material extrusion.
• Created hollow structures by solvent extraction of the core material post-printing.
• Introduced sulfonic acid functionalities through a sulfonation-induced crosslinking reaction to enhance chemical stability and pollutant affinity.

Main Results:

• Successfully fabricated 3D-printed hollow polymer sorbents with controllable void sizes and shell thicknesses.
• Demonstrated that larger voids and thinner shells improve structural integrity during sulfonation.
• Hollow sulfonated polypropylene sorbents showed strong affinity for cationic pollutants, with enhanced adsorption kinetics due to increased accessible surface area.

Conclusions:

• Additive manufacturing offers a promising route for creating advanced structured sorbents with hollow architectures.
• The developed hollow sulfonated polymer sorbents provide an effective solution for water contaminant removal.
• Optimized structural features, such as void size, significantly enhance both pollutant removal efficiency and adsorption speed.