Emissions of Secondary Formed ZnO Nano-Objects from the Combustion of Impregnated Wood. An Online Size-Resolved Elemental Investigation

Abstract

The release of secondary nano-objects formed during waste combustion processes is becoming a matter of concern, considering their known toxicity and the fact that the 100% efficiency of filtering systems is not always ensured. An increased cytotoxicity and genotoxicity on human peripheral blood lymphocytes is known particularly in the case of ZnO, which is often contained in paints and waterproof agents, heading to a relevant quantity present in the waste wood material. In this study, the behavior of ZnO nanoparticles during wood combustion and the effect of the reduction potential of generated carbon species on the release of secondarily formed ZnO-containing nano-objects were investigated. By hyphenating a modified scanning mobility particle sizer (SMPS) and inductively coupled mass spectrometry (ICP-MS), it was possible to obtain simultaneously size-resolved and chemical information on the emitted nanoparticles. Through the established correlation between SMPS and ICP-MS signals, Zn-containing particles were efficiently resolved from the combustion generated particles. Transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDS) on size-selected particles confirmed the SMPS and ICP-MS data. The use of electron diffraction allowed determining the structure of the crystalline materials as hexagonal ZnO. A possible mechanism of reduction of ZnO to Zn and further reformation as secondary nano-objects is proposed.

Elemental and Thermo-gravimetric Characterization of Trace Metals in Leaves and Soils as Bioindicators of Pollution in Kyiv City

“…However, the matrix and locally generated redox conditions can also affect the release of these metals. For Cd and Zn (having a boiling point of 765 °C and 907 °C, respectively), it is possible that they can volatilize in elemental form and re-form oxides by interacting with O 2 (Foppiano et al, 2018 ). A linear function can approximately fit the decrease of the metal signals during the isothermal regime (at 960 °C).…”

Evaporation of Metals during the Thermal Treatment of Oxide Nanomaterials in Cellulose-Based Matrices

“…Regarding the analytical development to investigate the fate of metal nanomaterials in thermal treatment processes, efforts are needed to further develop online analytical techniques. To study the chemical and physical phenomena involved in such processes when nanomaterials are thermally treated (such as the morphology), hyphenated methods combining spectrometry, such as ICP-MS/OES, and particle size analysis, such as SMPS (Scanning Mobility Particle Sizer) and APS (Aerosol Particle Sizer), showed the possibility to gain this information online and at the same time. , Because the nanomaterials are usually diluted in waste, ICP-MS can be used instead of ICP-OES to measure low concentrations of metals in gases. However, this requires appropriate sampling concepts to get rid of (or at least to reduce) the gas amount generated by the organic and inorganic matrix.…”

Airborne metal nanoparticles released by azides detonation: determination and potential public exposure

“…As described in Figure S1 (SI), the airborne particles can be directly collected on a transmission electron microscopy (TEM) grid after detonation 23,24 . Figure 1 shows an overview of the collected particles generated by the detonation of silver (a) and copper (b) azides, without any particle size selection tool.…”