Investigation of soot precursor molecules during inception by acetylene pyrolysis using reactive molecular dynamics

<p>Soot inception by acetylene pyrolysis at 1350–1800 K is investigated using reactive molecular dynamics. The composition and chemical structure of soot precursor molecules formed during inception are elucidated. During soot inception, increasing the process temperature leads to faster deplet...

Full description

Saved in:
Bibliographic Details
Main Authors: A. Ganguly, K. M. Mukut, S. Roy, G. Kelesidis, E. Goudeli
Format: Article
Language:English
Published: Copernicus Publications 2025-04-01
Series:Aerosol Research
Online Access:https://ar.copernicus.org/articles/3/185/2025/ar-3-185-2025.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850198956364005376
author A. Ganguly
K. M. Mukut
S. Roy
G. Kelesidis
E. Goudeli
author_facet A. Ganguly
K. M. Mukut
S. Roy
G. Kelesidis
E. Goudeli
author_sort A. Ganguly
collection DOAJ
description <p>Soot inception by acetylene pyrolysis at 1350–1800 K is investigated using reactive molecular dynamics. The composition and chemical structure of soot precursor molecules formed during inception are elucidated. During soot inception, increasing the process temperature leads to faster depletion of C<span class="inline-formula"><sub>2</sub></span>H<span class="inline-formula"><sub>2</sub></span> molecules and faster formation of C<span class="inline-formula"><sub>2</sub></span>H<span class="inline-formula"><sub>3</sub></span>, C<span class="inline-formula"><sub>2</sub></span>H<span class="inline-formula"><sub>4</sub></span>, C<span class="inline-formula"><sub>2</sub></span>H<span class="inline-formula"><sub>6</sub></span>, CH<span class="inline-formula"><sub>4</sub></span>, and C<span class="inline-formula"><sub>2</sub></span> with the concurrent appearance of H<span class="inline-formula"><sub>2</sub></span> molecules. Small molecules consisting of 1–5 C atoms (C<span class="inline-formula"><sub>1</sub></span>–C<span class="inline-formula"><sub>5</sub></span>) are formed due to reactive collisions and grow further to larger hydrocarbon compounds consisting of 6–10 C atoms. At initial stages of inception, prior to the formation of incipient soot, three-member rings are formed, which are associated with the formation of compounds with fewer than 10 C atoms. Once incipient soot is formed, the number of C<span class="inline-formula"><sub>1</sub></span>–C<span class="inline-formula"><sub>10</sub></span> compounds and the number of three-member rings drop, while the number of five- and six-member rings increases, indicating that the formation of larger rings is associated with the growth of soot clusters. The chemical structure of soot precursor molecules obtained by bond order analysis reveals that molecules with up to 10 C atoms are either linear or branched aliphatic compounds or may contain three-member rings fused with aliphatic components. Molecules with more than 10 C atoms often exhibit structures composed of five- or six-member C rings, decorated by aliphatic components. The identification of molecular precursors contributing to soot inception provides crucial insights into soot formation mechanisms, pinpointing potential pathways of soot formation during combustion.</p>
format Article
id doaj-art-f4490f5c9acb432ebab2f325802bdfd0
institution OA Journals
issn 2940-3391
language English
publishDate 2025-04-01
publisher Copernicus Publications
record_format Article
series Aerosol Research
spelling doaj-art-f4490f5c9acb432ebab2f325802bdfd02025-08-20T02:12:45ZengCopernicus PublicationsAerosol Research2940-33912025-04-01318520310.5194/ar-3-185-2025Investigation of soot precursor molecules during inception by acetylene pyrolysis using reactive molecular dynamicsA. Ganguly0K. M. Mukut1S. Roy2G. Kelesidis3E. Goudeli4Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria, AustraliaDepartment of Mechanical Engineering, Marquette University, Milwaukee, WI, USADepartment of Mechanical Engineering, Marquette University, Milwaukee, WI, USAFaculty of Aerospace Engineering, Delft University of Technology, Delft, the NetherlandsDepartment of Chemical Engineering, The University of Melbourne, Parkville, Victoria, Australia<p>Soot inception by acetylene pyrolysis at 1350–1800 K is investigated using reactive molecular dynamics. The composition and chemical structure of soot precursor molecules formed during inception are elucidated. During soot inception, increasing the process temperature leads to faster depletion of C<span class="inline-formula"><sub>2</sub></span>H<span class="inline-formula"><sub>2</sub></span> molecules and faster formation of C<span class="inline-formula"><sub>2</sub></span>H<span class="inline-formula"><sub>3</sub></span>, C<span class="inline-formula"><sub>2</sub></span>H<span class="inline-formula"><sub>4</sub></span>, C<span class="inline-formula"><sub>2</sub></span>H<span class="inline-formula"><sub>6</sub></span>, CH<span class="inline-formula"><sub>4</sub></span>, and C<span class="inline-formula"><sub>2</sub></span> with the concurrent appearance of H<span class="inline-formula"><sub>2</sub></span> molecules. Small molecules consisting of 1–5 C atoms (C<span class="inline-formula"><sub>1</sub></span>–C<span class="inline-formula"><sub>5</sub></span>) are formed due to reactive collisions and grow further to larger hydrocarbon compounds consisting of 6–10 C atoms. At initial stages of inception, prior to the formation of incipient soot, three-member rings are formed, which are associated with the formation of compounds with fewer than 10 C atoms. Once incipient soot is formed, the number of C<span class="inline-formula"><sub>1</sub></span>–C<span class="inline-formula"><sub>10</sub></span> compounds and the number of three-member rings drop, while the number of five- and six-member rings increases, indicating that the formation of larger rings is associated with the growth of soot clusters. The chemical structure of soot precursor molecules obtained by bond order analysis reveals that molecules with up to 10 C atoms are either linear or branched aliphatic compounds or may contain three-member rings fused with aliphatic components. Molecules with more than 10 C atoms often exhibit structures composed of five- or six-member C rings, decorated by aliphatic components. The identification of molecular precursors contributing to soot inception provides crucial insights into soot formation mechanisms, pinpointing potential pathways of soot formation during combustion.</p>https://ar.copernicus.org/articles/3/185/2025/ar-3-185-2025.pdf
spellingShingle A. Ganguly
K. M. Mukut
S. Roy
G. Kelesidis
E. Goudeli
Investigation of soot precursor molecules during inception by acetylene pyrolysis using reactive molecular dynamics
Aerosol Research
title Investigation of soot precursor molecules during inception by acetylene pyrolysis using reactive molecular dynamics
title_full Investigation of soot precursor molecules during inception by acetylene pyrolysis using reactive molecular dynamics
title_fullStr Investigation of soot precursor molecules during inception by acetylene pyrolysis using reactive molecular dynamics
title_full_unstemmed Investigation of soot precursor molecules during inception by acetylene pyrolysis using reactive molecular dynamics
title_short Investigation of soot precursor molecules during inception by acetylene pyrolysis using reactive molecular dynamics
title_sort investigation of soot precursor molecules during inception by acetylene pyrolysis using reactive molecular dynamics
url https://ar.copernicus.org/articles/3/185/2025/ar-3-185-2025.pdf
work_keys_str_mv AT aganguly investigationofsootprecursormoleculesduringinceptionbyacetylenepyrolysisusingreactivemoleculardynamics
AT kmmukut investigationofsootprecursormoleculesduringinceptionbyacetylenepyrolysisusingreactivemoleculardynamics
AT sroy investigationofsootprecursormoleculesduringinceptionbyacetylenepyrolysisusingreactivemoleculardynamics
AT gkelesidis investigationofsootprecursormoleculesduringinceptionbyacetylenepyrolysisusingreactivemoleculardynamics
AT egoudeli investigationofsootprecursormoleculesduringinceptionbyacetylenepyrolysisusingreactivemoleculardynamics