Optimizing Microplastic Removal using Biochar

Optimizing Microplastic Removal using Biochar Abstract Nowadays, plastics are almost a necessity in people's daily lives. Unfortunately, the process of plastic recycling is still in its infancy, and plastics are often discarded in the environment. That evokes a massive deposit of plastic products in rivers, lakes and oceans. This throw-away culture is not without consequences, as the 'end of life' of plastic products is not equal to an 'end of impact'. Plastics break down into smaller and smaller pieces. These so-called microplastics (MP) are persistent and cause health issues and ecotoxicological damage. The objective of this project is to optimize MPs removal using carbon-based materials such as biochar and activated carbon. These materials are environmentally friendly, sourced from renewable resources, and stable in water, making them safe for use without introducing additional pollutants. Biochar and activated carbon are effective for adsorbing microplastics due to their high surface area and porous structure, which allows them to trap microplastic particles. Their surface chemistry, including various functional groups, enables strong interactions with different types of microplastics. This study compared four different materials: 1) sand (which served as a control), 2) raw biochar, 3) coconut fiber, and 4) iron-modified biochar (Fe-Biochar) and four different temperature treated biochar (550°C,650°C,750°C,850°C). Approximately one gram of adsorbent material was exposed to a solution containing 0.2 and 0.02 µm sized labeled polystyrene MPs at a concentration of 1 mg/L. Periodic samples were collected and analyzed for MP concentration using a fluorescence spectrophotometer. The results indicated that the Fe-Biochar had the best performance, with an MPs removal efficiency of 99.99% within six hours. Biochar and coco fiber had an adsorption efficiency of 56% and 44%, respectively, in 48 hours, with sand showing only 29% removal efficiency after 72 hours. And the 850°C treated biochar removal 76% MPs within 48 hours. The results show that the negatively charged MP particles are highly attracted to Fe-Biochar media, and the largest surface area attached more MPs, leading to high removal. This paper was presented at WEFTEC 2025, held September 27-October 1, 2025 in Chicago, Illinois. Presentation time 09:30:00 09:45:00 Session time 08:30:00 10:00:00 Session Innovative Approaches to Micropollutant Removal in Wastewater Session location McCormick Place, Chicago, Illinois, USA Topic Contaminants of Emerging Concern & Trace Organics Topic Contaminants of Emerging Concern & Trace Organics Author(s) Song, Jianqiao, Venkiteshwaran, Kaushik, Dizbay-Onat, Melike, Winkler, Walker Author(s) J. Song 1 , K. Venkiteshwaran 1 , M. Dizbay-Onat 1 , W. Winkler 1 Author affiliation(s) University of South Alabama 1 Source Proceedings of the Water Environment Federation Document type Conference Paper Publisher Water Environment Federation Print publication date Oct 2025 DOI 10.2175/193864718825160020 Volume / Issue Content source WEFTEC Copyright 2025 Word count 6 Purchase price $11.50 Get access Log in Purchase content Purchase subscription You may already have access to this content if you have previously purchased this content or have a subscription. Log in Need to create an account? You can purchase access to this content but you might want to consider a subscription for a wide variety of items at a substantial discount! Purchase access to 'Optimizing Microplastic Removal using Biochar' Add to cart Purchase a subscription to gain access to 18,000+ Proceeding Papers, 25+ Fact Sheets, 20+ Technical Reports, 50+ magazine articles and select Technical Publications' chapters. Log in to view subscription options Log in to view rental option