Parkia speciosa: A basic heterogeneous catalyst for production of soybean oil-based biodiesel

•Fabrication of biomass derived heterogeneous catalyst from Parkia speciosa.•Calcination at 700 °C performed to generate the catalyst MB700.•Biodiesel yield of 96.4% obtained at optimum reaction conditions.•Catalyst was recyclable and showed 92.8% yield at the end of 5th cycle.