Development of a schwarzite-based moving bed 3D printed water treatment system for nanoplastic remediation.

Bramha Gupta,Rushikesh S Ambekar,Abhradeep Majumder,Ashok Kumar Gupta,Partha Kumbhakar,Raphael M Tromer,Chandra Sekhar Tiwary,P M Ajayan,Rupal Sinha,Douglas S Galvao,Partha Sarathi Ghosal

doi:10.1039/d1ra03097c

Abstract

The impact of micro and nanoplastic debris on our aquatic ecosystem is among the most prominent environmental challenges we face today. In addition, nanoplastics create significant concern for environmentalists because of their toxicity and difficulty in separation and removal. Here we report the development of a 3D printed moving bed water filter (M-3DPWF), which can perform as an efficient nanoplastic scavenger. The enhanced separation of the nanoplastics happens due to the creation of a charged filter material that traps the more surface charged nanoparticles selectively. Synthetic contaminated water from polycarbonate waste has been tested with the filter, and enhanced nanoplastic removal has been achieved. The proposed filtration mechanism of surface-charge based water cleaning is further validated using density function theory (semi-empirical) based simulation. The filter has also shown good structural and mechanical stability in both static and dynamic water conditions. The field suitability of the novel treatment system has also been confirmed using water from various sources, such as sea, river, and pond. Our results suggest that the newly developed water filter can be used for the removal of floating nanoparticles in water as a robust advanced treatment system.

Highlights

The extensive use of plastics and their subsequent unplanned disposal have made them one of the most notable water pollutants in the last few decades
M-3DPWF absorbed 11.43% water, while in the dynamical one, it absorbed 13.42% water. These results indicated that the water lter is highly stable in the stationary as well as in dynamical conditions
Considering the difficulties associated with the remediation of nanoplastics by conventional ltration processes, a novel 3D printed moving bed water lter has been developed with the opposite surface charged acrylonitrile butadiene styrene (ABS) media, selectively trapping the nanoplastics from the water

Summary

Introduction

Advanced physical treatment processes, such as dissolved air oatation, rapid sand lter, disc lters, and biological processes, have been employed to remove microplastics from the wastewater.[17,18,19,20,21] The average removal efficiency using disc lters was found to be around 40%, while dissolved air oatation and rapid sand ltration techniques accounted for removal of around 48% and 90%, respectively.[17]. 3D printing is the competitive technique due to its numerous advantages, such as its capability to fabricate complex structures, agility to print a wide spectrum of compatible materials, sustainability, and scalability.[30,31,32,33,34,35,36] a schwarzite-based 3D structured porous lter was used due to its large surface area, positive and negative curving topologies with tunable spongy size and shape, and intriguing properties These crystalline constructions can have a large number of porous unit cells, rigid foam-like materials with tunable mechanical and electronic properties.[27,37]. The proposed technology can be an advanced and feasible solution for the concerns of nanoplastics contamination in water bodies worldwide

Experimental details

Simulation details

Results and discussions

Conclusions