Catalytic performance of NiFe2O4 and Ni0.3Zn0.7Fe2O4 magnetic nanoparticles during biodiesel production

•NiFe2O4 and Ni0.3Zn0.7Fe2O4 magnetic nanoparticles were successfully synthesized via combustion reaction.•Structural, morphology and magnetism of the catalysts depend on amount of Zn2+.•The catalysts display very good performance during biodiesel production.•However, catalytic activity is influence by its acidity and zeta potential. In this study, catalytic performance of nanoferrites NiFe2O4 and Ni0.3Zn0.7Fe2O4 is reported. Nickel–ferrite and mixed nickel–zinc ferrite were successfully synthesized by combustion reaction using a conical reactor with production of 10 g per batch. Crystallinity and purity or quantitative analysis of the catalyst were checked by using X-ray diffraction and energy dispersive X-ray analysis. Surface chemistry was examined via Fourier transform infrared (FTIR) analysis; N2 physisorption at 77 K was conducted to obtain textural properties of the catalyst; a thermogravimetric analysis, a scanning electron microscope and a transmission electron microscopy were used to check the thermal stability and morphology of the catalyst, respectively. The catalysts were used to convert soybean oil into biodiesel in a batch mode and the reaction mixture was analyzed using a pre-calibrated gas chromatograph (GC). The presence of a single-phase spinel structure in the synthesized nanoparticles was confirmed by the XRD results. The Ni0.3Zn0.7Fe2O4 had a lower surface area value of 71.5 m2g−1 and higher saturation magnetization value of 31.50 emu/g than sample NiFe2O4 which had 87.6 m2g−1 and 17.85 emu/g, respectively. Biodiesel yield of 94% was obtained with Ni0.3Zn0.7Fe2O4 and 49% was obtained with NiFe2O4. Better performance of Ni0.3Zn0.7Fe2O4 when compared to that of NiFe2O4 could be attributed to higher acidity of the former. Findings from this study suggest that the development of nickel-zinc ferrite nanoparticles as magnetic heterogeneous catalysts could provide an environmentally friendly platform for biodiesel production.