Effects of the NiFe2O4 nanoadditive on the performance and emission characteristics of diesel engines: ultrasonic green synthesis by T3 hormone

Abstract

NiFe₂O₄ nanosheets were successfully synthesized via combined ultrasonic and combustion methods using triiodothyronine (T3) hormone as a biotemplate. Isodiesel and heavy diesel were selected as feedstocks to evaluate the ultrasound-assisted catalytic oxidation process. In this study, we focused on high performance of diesel engine with NiFe₂O₄ nanosheets. Various conditions such as catalyst dosage, hydrogen peroxide dosage, frequency range and catalyst morphologies of NiFe₂O₄ were investigated to achieve optimized conditions. High levels of sulfur compounds (98%) were removed using NiFe₂O₄ catalysts under determined conditions (1.0 g L⁻¹ catalyst, O/S mole ratio = 2, frequency = 40 kHz and morphology of the nanocatalyst = nanosheets). The nickel ferrite nano additive was mixed with isodiesel and heavy diesel using an ultrasonicator device to achieve better stability. The results indicated that under the optimum amount (1% w/v), the NiFe₂O₄ nanostructure is the best additive to reduce NO_x, CO, HC and smoke emission in diesel engines. Moreover, a change in the flash point and viscosity of diesel fuels was observed with the addition of nanosheets. NiFe₂O₄ could be recycled 3 times without a significant decrease in catalyst activity.