Performance and emission characteristics of a diesel engine fuelled by biodiesel from black soldier fly larvae: Effects of synthesizing catalysts with citric acid

Biodiesel has several environmental benefits, such as biodegradability, renewability and lower soot emissions. However, biodiesel has undesirable properties such as higher viscosity and density and low calorific value compared to petroleum diesel, resulting in high Brake Specific Fuel Consumption (BSFC), reduced Brake Power (BP) and increased NO(X) emissions creating an environmental concerns in biodiesel development. This study investigated the effects of synthesizing transesterification catalysts (CaO and NaOH) with Citric Acid (CA) on the quality of biodiesel and biodiesel blends produced from Black Soldier Fly Larvae (BSFL) (Hermetia Illucens). The quality of biodiesel and blends was determined based on fuel properties, engine performance and emission composition characteristics. The tests were performed on a single-cylinder, four-stroke, Compression Ignition (CI) diesel engine at five loads at a constant speed of 1500 rpm. The results showed that synthesizing the catalysts with CA significantly affected the fatty acid profile of the biodiesel compared to physical fuel properties. B100 (pure BSFL biodiesel) exhibited higher BSFC by 10.57–13.97 % and lower BP by 4.21–7.83 % than diesel fuel. However, the Brake Thermal Efficiency (BTE) of biodiesel was higher than that of diesel fuel by 0.82–4.34 % at maximum load. Synthesizing catalysts with CA improved the viscosity of biodiesel by 0.93–2.81 % and effectively reduced NO(X), HC and Smoke opacity by 2.23–3.16 %, 4.95–5.83 % and 20.51–41.15 %, respectively.