Development of 3D-Printed Permeable Reactive Barrier Adsorbents Utilizing Zeolite Composites for Copper (II) Removal in Acid Mine Drainage

Zeolite-based ceramic structures was fabricated using a viscous solution 3D printing (3DP) technique to demonstrate their effectiveness in removing heavy metal ions from acid mine drainage (AMD) runoff. Zeolite, a low-cost hydrated aluminosilicate clay, is widely used in water treatment due to its excellent ion-exchange and adsorption capabilities. In the Philippines, abundant reserves of natural zeolite (Philippine Natural Zeolite, PNZ) have been utilized in various separation and purification applications. However, traditional forms of zeolite—such as loose granules or powders—are difficult to deploy and recover from environmental systems. This study employed a Direct Ink Writing (Eazao Bio) – a commercially available benchtop multi-material 3D printer to create custom, structured zeolite composite devices that are deployable, retrievable, and reusable. These 3D-printed structures offer improved efficiency in extracting heavy metals from AMD. Furthermore, surface modification and functionalization of the 3D-printable ink significantly enhance the adsorption performance of the final product, making it a promising sorbent material for use in permeable reactive barriers (PRBs).