Production, characterization, and emission characteristics of biodiesel derived from castor (<i>Ricinus communis</i>) and black mustard (<i>Brassica nigra</i>) seeds

In this work, biodiesel was synthesized from castor and black mustard oil seeds, through homogenous alkaline transesterification with methanol. The impact of parameters such as alcohol amount, catalyst quantity, temperature, and reaction time have been optimized. The yield of castor biodiesel (COB) was 93.53% w/w at 20.7 wt.% methanol, and black mustard biodiesel (MOB) was 93.88% w/w at 20 wt.% methanol. The other conditions wt.% KOH, temperature, and reaction time were 0.5, 60 °C, and 60 min respectively. (COB) and (MOB) were mixed with diesel fuel (DI) in various ratios to obtain (B5, B10, B15, B20, B30, and B50), and the physicochemical properties of biodiesel are measured employing ASTM standards. The diesel one-cylinder engine was used as a test engine. CO2, CO, NOx, and SO2 emissions from biodiesel and its blends were measured and compared to DI. COB and MOB blends emitted less CO2, CO, and SO2 emissions than DI, along with a slight increase in NOx emissions. Based on the results, (COB) and (MOB) were reliable substitute fuels for reducing environmental pollution.