3D-Printed Materials for Wastewater Treatment

Abstract

The increasing levels of water pollution pose an imminent threat to human health and the environment. Current modalities of wastewater treatment necessitate expensive instrumentation and generate large amounts of waste, thus failing to provide ecofriendly and sustainable solutions for water purification. Over the years, novel additive manufacturing technology, also known as three-dimensional (3D) printing, has propelled remarkable innovation in different disciplines owing to its capability to fabricate customized geometric objects rapidly and cost-effectively with minimal byproducts and hence undoubtedly emerged as a promising alternative for wastewater treatment. Especially in membrane technology, 3D printing enables the designing of ultrathin membranes and membrane modules layer-by-layer with different morphologies, complex hierarchical structures, and a wide variety of materials otherwise unmet using conventional fabrication strategies. Extensive research has been dedicated to preparing membrane spacers with excellent surface properties, potentially improving the membrane filtration performance for water remediation. The revolutionary developments in membrane module fabrication have driven the utilization of 3D printing approaches toward manufacturing advanced membrane components, including biocarriers, sorbents, catalysts, and even whole membranes. This perspective highlights recent advances and essential outcomes in 3D printing technologies for wastewater treatment. First, different 3D printing techniques, such as material extrusion, selective laser sintering (SLS), and vat photopolymerization, emphasizing membrane fabrication, are briefly discussed. Importantly, in this Perspective, we focus on the unique 3D-printed membrane modules, namely, feed spacers, biocarriers, sorbents, and so on. The unparalleled advantages of 3D printed membrane components in surface area, geometry, and thickness and their influence on antifouling, removal efficiency, and overall membrane performance are underlined. Moreover, the salient applications of 3D printing technologies for water desalination, oil–water separation, heavy metal and organic pollutant removal, and nuclear decontamination are also outlined. This Perspective summarizes the recent works, current limitations, and future outlook of 3D-printed membrane technologies for wastewater treatment.

Recent advancement in viologen functionalized porous organic polymers (vPOPs) for energy and environmental remediation

“…Significant progress has been made in developing very effective adsorbents for separation methods that rely on sorption in the last several years. 54,55 In the field of pollutant removal from water and wastewater treatment, vPOPs have been regarded as highly promising absorbent substances because of their distinctive properties such as redox activity, tuneable pore diameter, free exchangeable anions and so on. Here, we have categorized pollutants into two classes, namely,: (i) organic pollutants and (ii) inorganic pollutants, and discussed the role of vPOPs in removing them from water thoroughly.…”

4D hydrogels: fabrication strategies, stimulation mechanisms, and biomedical applications

“…Additionally, 3D hydrogels undergo shape morphism to produce more complex designs and shapes, also known as four-dimensional (4D) fabrication. 32,33 There are multiple actuators that can drive shape morphism within hydrogels, such as pH, temperature, light, and ions. [34][35][36] In the case of 4D fabrication, hydrogel structures can change their shape or properties over time in response to environmental cues, making them attractive for tissue engineering, drug delivery, and soft robotics applications.…”

Nano-enabled 3D-Printed Structures for Water Treatment

“…To date, a majority of the reviews published on the environmental application of 3D-printed structures have predominantly explored the fabrication of membranes and membrane spacers, with some reference to studies incorporating nanomaterials to enhance their water treatment performance. − The recent increase in the number of studies focusing on the integration of nanomaterials into 3D printing feedstock for improved environmental performance of the resulting structures requires a comprehensive review exploring the nano-enabling strategies, the current state of the art, and prospects for future developments. This review focuses specifically on studies that have investigated the addition of nanomaterials into 3D-printed structures for water treatment applications.…”