Interaction of metal oxide nanoparticles with microplastics: Impact of weathering under riverine conditions

WATER RESEARCH

卷:189

Article

Singh, Nisha¹  Khandelwal, Nitin¹  Tiwari, Ekta¹  Naskar, Nabanita²  Lahiri, Susanta²  Luetzenkirchen, Johannes³  Darbha, Gopala Krishna^1,4 

[1] Indian Inst Sci Educ & Res Kolkata, Dept Earth Sci, Environm Nanosci Lab, Mohanpur 741246, W Bengal, India

[2] Saha Inst Nucl Phys Kolkata, Chem Sci Div, Kolkata 700019, W Bengal, India

[3] Karlsruhe Inst Technol KIT, Inst Nucl Waste Disposal INE, D-76344 Eggenstein Leopoldshafen, Germany

[4] Indian Inst Sci Educ & Res Kolkata, Ctr Climate & Environm Studies, Mohanpur 741246, W Bengal, India

关键词: Cerium oxide;    Polypropylene;    Sorption;    Batch experiments;    Roughness;   

DOI  :  10.1016/j.watres.2020.116622

来源: Elsevier

【 摘 要 】

The ubiquitous distribution of microplastics (MPs) leads to inevitable interactions with the toxic pollutants present in the environment including metal-oxide nanoparticles. This study investigates the interaction of CeO2 nanoparticles (CeNPs) with MPs generated from a disposable plastic container. Further, rough MPs (R-MPs), generated through mechanical abrasion of MPs with sand, were used to probe the impact of roughness. To understand the sorption kinetics and underlying interaction processes, batch experiments were carried out. The results distinctly indicate that CeNPs sorption occurred on MPs surfaces and was consistent with the pseudo-second order kinetics model. For pristine MPs, the sorption capacity was as high as 12.9 mg/g while for R-MPs kinetic equilibrium was achieved faster and an enhanced sorption capacity (13.4 mg/g) was identified. A rise in sorption with an increase in salinity was noted while pH and humic acid exhibited a negative correlation. The observed interactions were attributed to the aggregation profile and surface charge of CeNPs and MPs. Surprisingly, CeNPs also got loaded onto MPs in non-agitated and undisturbed conditions. The sorption process was influenced by the type of aqueous matrix and the sorption capacity at equilibrium followed the trend: distilled water> synthetic freshwater> river water. FTIR spectra, zeta potential, SEM imaging, and elemental mapping revealed electrostatic interaction as the dominant mechanism. This work contributes towards the knowledge gap on the environmental risk of MPs. (C) 2020 Elsevier Ltd. All rights reserved.

【 授权许可】

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