The catalytic potential of calcium oxide synthesized from mud clam shell as a heterogeneous catalyst for biodiesel production was studied. The mud clam shell calcium oxide was characterized using particle size analyzer, Fourier transform infrared spectroscopy, scanning electron microscopy, and BET gas sorption analyzer. The catalyst performance of mud clam shell calcium oxide was studied in the transesterification of castor oil as biodiesel. Catalyst characterization and transesterification study results of synthesized catalyst proved the efficiency of the natural derived catalyst for biodiesel production. A highest biodiesel yield of 96.7% was obtained at optimal parameters such as 1 : 14 oil-to-methanol molar ratio, 3% w/w catalyst concentration, 60°C reaction temperature, and 2-hour reaction time. Catalyst reusability test shows that the synthesized calcium oxide from mud clam shell is reusable up to 5 times.

Various heterogeneous catalysts are often used to produce biodiesel from non-edible crude oils. In this study a highly active heterogeneous calcium oxide (CaO) nanocatalyst with a diameter and surface area of 66 ± 3 nm and 90.61 m2/g, respectively, was synthesized from Polymedosa erosa (P. erosa) seashells through a calcination-hydration-dehydration technique. The nano-CaO catalysis impact was investigated in a two-step transesterification of triglycerides from crude Jatropha oil as a biodiesel along with other reaction parameters such as catalyst ratio, reaction time, and methanol to oil ratio. Fourier transform infrared spectroscopy, transmission electron microscope, X-ray diffraction, and Brunauer-Emmett-Teller spectrographic techniques were utilized to evaluate the CaO nanocatalyst spectral and structural characteristics. The effect of the transesterification parameters on reaction kinetics and Jatropha biodiesel (JB) yield were analyzed by employing a three-factor-five-level response surface methodology model based on a full factorial, two-block, central composite design. The adequacy of the predicted model was verified, and a 98.54% JB yield was reported at optimal parametric conditions, i.e., 0.02:1 (w/w) catalyst ratio, 133.1 min reaction time, and 5.15:1 mol/mol of methanol to the pretreated oil. An average of 95.8% JB yield was obtained from the catalyst reusability up to the sixth cycle. Fuel property test results of JB were found to be highly commensurate with the biodiesel standard EN 14214.

The physiochemical properties of biodiesel are significantly influenced by its fatty acid composition (FAC). This research investigates FAC of Jatropha biodiesel (JB) synthesized using feedstocks originated from the east (JBEM) and west (JBWM) Malaysian regions together with biofuel properties. The critical properties of pure biodiesels and blends were analysed according to ASTM D6751/EN 14214 standards. The JB properties were precisely regulated by its FAC features such as saturated fatty acids (SFAs), unsaturated fatty acids (USFAs), degree of unsaturation, and long chain saturated factor. The influence of SFA and USFA was inversely associated over biodiesel properties. The presence of higher SFA greatly affects biodiesel properties like the cetane number, cold filter plugging point, kinematic viscosity, density, cloud point, and pour point; conversely, the fuel properties such as oxidation stability, iodine value, acid value, water content, and flash point were improving with USFA contents. Blending of biofuels with petro diesels considerably improved their fuel properties.

The application of nonedible feedstock for the production of biodiesel has become an area of research interest among clean energy experts in the past few years. This research is aimed at the utilization of Pongamia pinnata (karanja), a nonedible feedstock from the state of Sarawak, Malaysia, to produce biodiesel to be known as crude karanja oil (CKO). A one-step transesterification process utilizing 7 : 1-10 : 1 wt% methanol (CH 3 OH) and 0.5-1.2 wt% sodium hydroxide (NaOH) at 65 ∘ C for 1.5 hrs has been used for the biodiesel production yielding 84% conversion. The physiochemical properties of the CKO produced revealed that it conforms with EN14214 standards for brake power (BP), brake specific fuel consumption (BSFC), and brake thermal efficiency (BTE) as they are all noted be optimal at B40.

Biodiesel is one of the promising renewable sources to fulfill the future energy demand of the world. Sustainable feedstock for biodiesel production is one of the major criteria to ensure the process of renewability. Chicken fat is an encouraging feedstock for biodiesel. In this study, waste chicken fat was converted to biodiesel via catalysed transesterification. Optimised process parameters were recorded at 1:4 oil-to-methanol volume ratio and 0.5 wt% KOH catalyst concentration with a biodiesel yield of 96%. The FT-IR spectral analysis of chicken fat and chicken fat biodiesel confirmed the conversion of chicken fats into biodiesel. The physico-chemical properties of biodiesel were tested in accordance with ASTM D6751 and EN 14214 biodiesel standards. The specific fuel properties of chicken fat biodiesel that include calorific value, viscosity and acid value were found to be lower than that of petrodiesel. The diesel engine performance tests confirmed that the biodiesel blends performance was similar to petrodiesel.  It is noted that while the brake horsepower increased with the increase of biodiesel blending percentage, the engine power output was found to decrease. Specific fuel consumption also increased along with the biodiesel blending percentage.