Successful Removal of Microplastics from Municipal Wastewater Using a Combination of Technologies (Treatment Train): Coagulation and Cobalt-Based Nanostructures
Irtiqa Imini Pishgiri Masdumiyat (Safety Promotion and Injury Prevention),
Vol. 13 No. 4 (1404),
17 August 2026
,
Page 44-58
https://doi.org/10.22037/iipm.v13i4.52875
Abstract
Background and Aim: The aim of this study was to enhance advanced oxidation processes (AOPs) using nanoparticles. In this regard, developing a photo catalyst-based advanced oxidation process could provide an appropriate solution for removing these pollutants under light irradiation.
Methods: The selection of an appropriate treatment process for microplastics and nanoplastics depends on the desired water quality, particle size, presence of natural organic matter, and energy and cost constraints. The integration of multiple technologies is more effective than relying on a single treatment unit. Conventional approaches include adsorption, biochar, activated carbon, coagulation–flocculation, flotation, microfiltration, ultrafiltration, nanofiltration, and reverse osmosis, which concentrate or separate these particles. Therefore, the application of advanced oxidation processes is essential for the subsequent degradation of these concentrated secondary contaminants.
Results: When combined with alum flocculation, this photocatalyst reduced the number of microplastics in the influent wastewater of Treatment Plant A from 3979±420 to 454±4 particles and in Treatment Plant B from 4651±135 to 561±6 particles in the final effluent. Under optimal conditions, the reduction in the number of microplastics throughout the entire process reached 87.7–88.6%, which was attributed to the separation and degradation of the PET and PP polymer structures. Furthermore, the use of Co₃O₄/g-C₃N₄ photocatalyst after flocculation resulted in a reduction in microplastic mass, as an indicator of photocatalytic degradation, of approximately 68% for PET and 66.1% for PP. Therefore, this combined method not only effectively separated microplastics from the aqueous phase but also, through photocatalytic degradation, reduced the mass and caused structural changes in a portion of the polymers.
Conclusion: The study showed that the combination of coagulation and Co₃O₄/g-C₃N₄ nanocomposite for PMS activation enabled the degradation of PET and PP microplastics under UVC irradiation. XRD and FESEM results confirmed Co₃O₄ loading and the formation of a Z-scheme heterojunction, indicating enhanced electron transfer and reactive species generation.
- واژههای کلیدی : میکروپلاستیکها ؛ تصفیه فاضلاب شهری؛ اکسیداسیون پیشرفته؛ پراکسیمونوسولفات؛ نانوساختار Co₃O₄/g C₃N₄
How to Cite
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