Mostafa, AMustafa, AhmadYoussef, IMourad, M2022-02-102022-02-102022-01https://doi.org/10.14456/ea.2022.11http://repository.msa.edu.eg/xmlui/handle/123456789/4839ScopusFinding sustainable alternative fuel to substitute fossil fuel is a study area of interest for most organizations and societies. Such alternative energy should keep the balance between emissions improvement and diesel engine performance. Water-diesel (W/D) emulsion fuel is considered as an auspicious alternative fuel that can improve diesel engine performance and lower harmful exhaust emissions. This review critically discusses the effect of the obtained blend on diesel engine performance and emission characteristics based on the available experimental findings in the literature. The review also highlights the concept of water-diesel emulsion fuel, surfactant, and hydrophilic-lipophilic balance value (HLB). The types of emulsion and micro-explosion phenomena were also discussed. According to the literature review, most of the researchers suggested a significant improvement of the environmental footprint when W/D is used to reduce particulate matter (PM) and nitrogen oxides (NOX). However, other studies criticize the increase in carbon monoxide (CO) and hydrocarbon (HC) emissions. © 2022, Thai Society of Higher Eduation Institutes on Environment. All rights reserved.en-USEmissions characteristicsEngine performanceMicro-explosion phenomenonWater-diesel emulsionArticlehttps://doi.org/10.14456/ea.2022.11