Improving performance and emissions characteristics of compression ignition engine: Effect of ferrocene nanoparticles to diesel-biodiesel blend

•Ferrocene nanoparticles improves CI thermal efficiency by 3% for diesel fuel.•Ferrocene nanoparticles improves CI thermal efficiency by 8% for B30 fuel.•Biodiesel blend could be increased without loss in engine power.•Ferrocene improves NOx and CO2 emissions for both base fuels. The impact of different concentrations of ferrocene nanoparticles to diesel and B30 (30%biodiesel and 70% diesel) base fuels on performance, combustion characteristics, and CO2 and NOx emissions characteristics of a compression ignition (CI) engine is investigated. The biodiesel was prepared through esterification and transesterification processes to waste frying oil. A 4-stroke, air-cooled, single cylinder CI engine was used to perform these experiments. The results revealed that thermal efficiency of CI engine running on B30 fuel was less than this of neat diesel fuel. The addition of ferrocene to diesel and B30 base fuels has increased brake thermal efficiency by 3% and 8%, respectively. The optimal concentrations of ferrocene nanoparticles in diesel and B30 base fuels were specified as 250 and 300 mg/L, respectively. The ferrocene has increased CO2 and decreased NOx emissions for diesel fuel at medium and high loads. Adding ferrocene to B30 base fuel has increased CO2 at all loads while NOx has only decreased at high loads, respectively.