Abstract

The influence of n-heptane mixed with jatropha oil methyl ester (JOME)–diesel with different metal oxide additions, such as aluminum oxide (Al2O3), titanium dioxide (TiO2), and carbon-based nanoparticles (NPs) including multiwalled carbon nanotubes (MWCNTs) at a quantity of 60 mg/L, and enrichment of hydrogen (H2) at a quantity of 6 lpm are studied on a diesel engine to understand the crucial combustion parameters. The combustion and emission parameters are mainly affected by the inclusion of NPs and H2 infusion. The 20 vol% of JOME is mixed with 80 vol% of neat diesel to prepare the B20 blend. The n-heptane at a quantity of 10 vol% is blended in the B20 to prepare the B20H10 blend. Further, the fictionalized NPs with QPAN80 surfactant are blended in the B20H10 blend and supplied to the Compression Ignition engine as a pilot fuel, and H2 at 6 lpm is supplied with the intake air. The NPs to surfactant ratio is optimized at a ratio of 1:4, and the prepared blends are found to be homogeneous and stable. The B20–n-heptane–NP blends with H2 infusion significantly enhanced performance and combustion, and pollutants are greatly reduced. The brake thermal efficiency, cylinder pressure, and heat release rate are improved by about 10.9%, 33.3%, and 9.14%, respectively, for the B20H10 + MWCNT60 + 6H2 blend than D100. The brake-specific fuel consumption, carbon monoxide (CO), carbon dioxide (CO2), and hydrocarbon (HC) emissions are reduced by 16.6%, 15.4%, 10.7%, and 10.8%, respectively, however, the Nitrogen Oxide (NOx) emissions are increased with H2 infusion. © 2025 The Authors. Energy Science & Engineering published by Society of Chemical Industry and John Wiley & Sons Ltd.