Comparative study of the soot formation process in a “nucleation” and a “sooting” low pressure premixed methane flame

Unveiling trends in soot nucleation and growth: When secondary ion mass spectrometry meets statistical analysis

“…In addition, the criteria used to identify soot particles in the condensed phase are often based on the experimental measurements used to identify them, thus over the years a variety of definitions partially overlapping or contradicting each other arose [6][7][8][9][10][11]. The emission of thermal radiation is one of the possible criteria to identify nascent soot particles (NSPs), which can be operationally defined as the smallest entities in the condensed phase capable of emitting radiation described by Planck's law (often cited as blackbody-like or graybody radiation) [8].Soot particles are generally at thermal equilibrium with the combustion gas, and therefore emit thermal radiation in a continuous spectrum that can be fitted with Planck's law. This emission can be used to identify soot particles even as their size approaches the limit of large organic molecules or small molecular clusters [12,13].…”

A comprehensive protocol for chemical analysis of flame combustion emissions by secondary ion mass spectrometry

“…Although the wafer surface ROI d provides chemical information on the condensable gas phase, the contributions to the mass spectra from condensable gas and soot particles cannot be easily separated on the soot deposit ROI c. This asymmetry is due to the larger diffusion coefficient of the gas compared to the particles. This approach is a further improvement of our previous work based on deposition on microfiber glass filters . In particular, soot particles and condensable gas tend to form a homogenous mix on the surface of the glass microfiber filters, and, as a result, their contributions are very tricky to separate.…”

“…However, it is reasonable to believe that post‐sampling aggregation does not affect the surface chemical composition, and therefore TOF‐SIMS surface analysis is still expected to be representative of the surface chemical composition of the sampled particles. Furthermore, it has already been shown for a premixed flame that the condensed gas phase contains masses as high as m / z 400. A similar mass distribution is identified for the zone outside the soot spot in this work (Figure D).…”

Particulate Matter Produced by Micro-Scale Biomass Combustion in an Oxygen-Lean Atmosphere

“…Modelling of soot formation is based on experimental work on laminar flames of simple and clean fuels like ethylene and methylene, and to date, no model describes the formation precisely. But there is an agreement on the basic mechanism of soot formation, and a mechanism known as HACA -hydrogen abstraction-C 2 H 2 addition, that also describes the evolution of PAHs, manages to describe the nucleation of soot [18]. For the description of this mechanism, a basic chemical and physical frame was created.…”

“…These two steps are creating agglomerates that, after further reactions, turn into impure carbon nuclei. Oxidation by O 2 and OH appears at all steps [18]. The main source of these pollutants is incomplete combustion and is controllable to some degree, because when biomass is combusted on grate pyrolysis always takes place, by the quality of the combustion process.…”