Eco-friendly magnetic biochar: An effective trap for nanoplastics of varying surface functionality and size in the aqueous environment

The surge in nano/microplastics (NPs/MPs) through myriad daily products released in the aqueous environment highlights the importance of the urgent development of mitigation techniques. The study has assessed the performance of iron-modified biochar pyrolyzed at two different temperatures, i.e., 550 °C (FB-550) and 850 °C (FB-850), with magnetic extractability for the easy and prompt removal of NPs of varying size and surface functionality. NP1 (1000 nm, carboxyl), NP2 (1000 nm, amine), and NP3 (30 nm, carboxyl) were subjected to batch experiments with the composites. Rapid elimination of all the NPs (<10 min) from the water system using robust magnetic-composites was observed. A higher-order of reaction kinetics (n > 2) was found through the general order model, and a good fit for Sips isotherm suggests ultrafast NPs removal and heterogeneous nature of the composite surface. Maximum removal capacities for NP1 (225.11 mg/g), and NP3 (206.46 mg/g) were obtained using FB-850, whereas FB-550 showed higher removal of NP2 (290.20 mg/g). The influence of solution pH on the sorption of NPs was limited with significant variation in zeta potential, suggesting the probability of surface complexation of NPs. The spectroscopic analysis of reaction mixture showed the disappearance of COO− peak, generation of FeOOH stretching, and shift in Fe-O band, confirming the involvement of surface complexation in the sorption process. Minimal impact of environmental parameters, reaction spontaneity, and efficient removal of NPs in complex aqueous matrices justify the composites’ environmental applicability. No-iron release and excellent reusability of the utilized adsorbents support the large-scale applicability of the composites.

Latest Posts

Policy Brief: Role of chemicals and polymers of concern in the global plastics treaty

This policy brief provides arguments on and insights into why and how plastic chemicals and polymers of concern should be integrated in the global plastics treaty. The document is an output of the Scientists’ Coalition for an Effective Plastics Treaty (SCEPT working group on chemicals, polymers and products) and aims at policymakers involved in the Intergovernmental Negotiation Committee[…]

Characteristics of microplastics in the beach sediments of Marina tourist beach, Chennai, India

The paper provides new insights into marine environments and human activities and suggests plastic waste should be controlled through laws that regulate waste sources and plastic additives in order to solve the problem of plastic accumulation in the oceans.

Microplastic pollution in coastal ecosystem off Mumbai coast, India

The paper strengthens the evidence that microplastics are present in the studied biota, suggesting that they are transferred between trophic levels through the interconnected food chain/web. The presence of micro plastics in fish guts highlights the need for further research on processing interventions for reducing microplastic contamination.

Personal protective equipment (PPE) pollution driven by the COVID-19 pandemic in coastal environment, Southeast Coast of India

PPE (face masks and gloves) were surveyed at six Indian beaches. There were 496 PPE counted with an average density of 1.08 × 10−3 PPE m−2. Previous studies found similar PPE density. Face masks accounted for 98.39% of all PPE recorded, while gloves accounted for only 1.61%. As a result of the increase in vaccination[…]

Effects of Marine Littering and Sustainable Measures to Reduce Marine Pollution in India

The research seeks to depict and reduce marine plastic pollution in India. A GIS map has been created to show plastic input from different river basins. In order to address the challenges of marine litter in India, a guiding model has been developed. According to the predictive model, India produces 536 thousand tons of municipal[…]