We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Reactivity of selected model microplastics with ozone
AI summary Read the abstract
Researchers conducted the first laboratory study on the reactivity of model microplastics — PEEK, PTFE, LDPE, and PET — with atmospheric ozone, finding that ozone alters the surface chemistry of these plastics in ways that could affect their environmental fate and potential to carry other pollutants.
Microplastics (MPs) are nowadays observed in all environmental compartments. However, in the atmosphere, the presence of this new pollutant is not well documented and not well understood. So far, atmospheric microplastic particles have been observed in megacities,1 in remote mountain areas2 and even over the open ocean,3 albeit in low concentrations. Microplastics exposed to the atmosphere, undergo ageing under the influence of atmospheric oxidants and sunlight. As the MPs are altered over time, their physicochemical properties are modified. In particular, the polymer structure of MPs can become more porous increasing their exposed surface compared to their new counterparts. This in turn can lead to an increased reactivity between atmospheric oxidants / pollutants and polymers. Furthermore, their physicochemical changes can ultimately lead to fragmentation, giving rise to the formation of more and smaller particles. It therefore seems important to quantify the reactivity of these new pollutants with atmospheric oxidants, as this can affect the role of MPs in the atmosphere, and their environmental fate. The present study provides the first results of a laboratory study on the reactivity of model microplastics, PEEK, PTFE, LDPE, PET, with ozone in a in a DRIFT (Diffuse Reflectance Infrared Fourier Transform) optical cell for the in-situ monitoring of MPs surface aging, coupled with an ozone analyser and a soft ionization Mass spectrometer (SIFT-MS), for the real-time monitoring of the gas-phase. The in-situ monitoring of MPs properties with DRIFTs revealed important chemical changes on their surface due to their exposition to ozone. We suggest that carboxylic acids and/or esters are amongst the most prominent reaction products. We also determine the ozone uptake coefficient (γss) of the MPs, and the evolution of their specific surface area before and after exposure to ozone. The values of γss measured are in the range of 10-8 to 10-9, indicating that MPs are not an important sink of gaseous O3 in the atmosphere. Further analysis of the gas-phase with SIFT-MS, evidenced the formation of VOCs and particularly carboxylic acids amongst the most prominent reaction products of MPs reaction with ozone. The impact of the modification of chemical functionalities at the surface of these microplastic on their environmental behaviour (e.g. hygroscopicity) and the reactivity of microplastics on the composition of the atmosphere is further discussed.Ref. : [1] Dris et al., 2015, Environ. Chem / [2] Allen et al., 2015, Nat. Geosci. / [3] Trainic et al., 2020, Commun. Earth Environ.
More Papers Like This
Reactivity of four model microplastics with ozone.
AI summary Read the abstract
Researchers investigated the reactivity of four model microplastic types with ozone, examining how ozone treatment affects the physicochemical properties of microplastics as a potential water treatment strategy for degrading plastic particles.
Changes in physical and chemical properties of microplastics by ozonation
AI summary Read the abstract
Researchers examined how ozone treatment in water systems changes the physical and chemical properties of six common types of microplastics. They found that ozonation altered surface roughness, wettability, and chemical composition of the plastics, with some types being more affected than others. The findings are important because these changes could influence how microplastics interact with other pollutants and organisms in treated water.
Surface modification of polyethylene microplastic particles during the aqueous-phase ozonation process
AI summary Read the abstract
Researchers examined the surface modification of polyethylene microplastics during aqueous-phase ozonation, finding that increasing ozone dosage and exposure time progressively increased carbonyl and hydroxyl functional groups on the particle surface. FTIR and XPS analysis showed ozonation altered the surface chemistry of polyethylene microplastics in ways that could change their environmental fate and pollutant adsorption capacity.
Comparison of surficial modification of micro-sized polyethylenein between by UV/O3 and UVO submerged system
AI summary Read the abstract
Researchers compared ozone and UV oxidation methods for chemically modifying the surface of polyethylene microplastics in water, finding that different treatment combinations create distinct surface changes. Understanding how weathering alters microplastic surfaces is important for predicting their environmental behavior and toxicity.
The effect of Ozonation on the chemical structure of microplastics
AI summary Read the abstract
Ozone treatment of microplastics in water caused oxidative changes to polymer surfaces including carbonyl group formation and surface cracking, which altered hydrophobicity and potentially increased the capacity of treated particles to adsorb contaminants, suggesting that ozonation in water treatment may chemically transform rather than eliminate microplastic hazards.
Research digests by email
When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.