Particulate number emissions during cold-start with diesel and biofuels: A special focus on particle size distribution

Ali Zare, Timothy A. Bodisco, Puneet Verma, Mohammad Jafari, Meisam Babaie, Liping Yang, Mostafiz Rahman, Andrew P.W. Banks, Zoran D. Ristovski, Richard J. Brown, Svetlana Stevanovic

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    5 Citations (Scopus)
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    The share of biofuels in the transportation sector is increasing. Previous studies revealed that the use of biofuels decreases the size of particles (which is linked to an increase in particulate toxicity). Current emission regulations do not consider small particles (sub-23 nm); however, there is a focus in future emissions regulations on small particles. These and the fact that within cold-start emissions are higher than during the warmed-up operation highlight the importance of a research that studies particulate matter emissions during cold-start. This research investigates the influence of biofuel on PN and PM concentration, size distribution, median diameter and cumulative share at different size ranges (including sub-23 nm and nucleation mode) during cold-start and warm-up operations using diesel and 10, 15 and 20% mixture (coconut biofuel blended with diesel). During cold-start, between 19 and 29% of total PN and less than 0.8% of total PM were related to the nucleation mode (sub-50 nm). Out of that, the share of sub-23 nm was up to 9% for PN while less than 0.02% for PM. By using biofuel, PN increased between 27 and 57% at cold-start; while, the increase was between 4 and 19% during hot-operation. The median diameter also decreased at cold-start and the nucleation mode particles (including sub-23 nm particles) significantly increased. This is an important observation because using biofuel can have a more adverse impact within cold-start period which is inevitable in most vehicles’ daily driving schedules.

    Original languageEnglish
    Article number101953
    Number of pages11
    JournalSustainable Energy Technologies and Assessments
    Early online date8 Jan 2022
    Publication statusPublished - Jun 2022

    Bibliographical note

    © 2022, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International

    Copyright © and Moral Rights are retained by the author(s) and/ or other copyright owners. A copy can be downloaded for personal non-commercial research or study, without prior permission or charge. This item cannot be reproduced or quoted extensively from without first obtaining permission in writing from the copyright holder(s). The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the copyright holders.

    Funding Information:
    The authors would like to acknowledge the support of Australian Research Council Linkage Projects funding scheme (project number LP110200158), Prof. Jochen Mueller, Mr. Andrew Elder and Mr. Noel Hartnett for their assistance.

    Publisher Copyright:
    © 2022 Elsevier Ltd


    • Biofuel
    • Cold-start
    • PN
    • Particle size distribution
    • Sub-23 nm

    ASJC Scopus subject areas

    • Renewable Energy, Sustainability and the Environment
    • Energy Engineering and Power Technology


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