Biodiesel methyl ester production and testing from selected African tropical seed oil feedstocks

摘要

The urgent need for alternative energy, climate change mitigation and environmental protection in the world today cannot be over-emphasized. Researchers are at top gear in search of non-edible energy crops. The huge environmental benefits of renewable energy notwithstanding, new discoveries in this area arise every day. The potentials of selected tropical seed-oils for biodiesel production and utilization as fuels were therefore explored and subsequently produced. The seed-oils studied include: sand box tree, fluted pumpkin seed and wild melon seeds. Oils of these seeds were extracted, optimized, synthesized and characterized as biodiesel fuels by transesterification process using different alcohol/oil ratios of (4:1 and 6:1) and catalysts types (NaOH and KOH) at optimization temperatures of 38oC and 55oC and reaction time of 5 mins and 30 mins respectively. Optimized biodiesel produced were investigated for their chemo-physical properties in conformity with ASTM standards of biodiesel. Results showed that sandbox tree seeds, wild melon seeds and pumpkin seeds have high percentage oil content (69.32%; 70.24% and 46.88%) respectively. They also hold great potentials as feedstocks in biodiesel production. Chemo-physical properties of the biodiesel produced as well as their blends with automotive gas oil (AGO) fell within specification. Pumpkin seed oil however showed highest average percentage optimized yield of biodiesel (97%) in (1 wt of oil), NaOH catalyst, and alcohol to oil ratio of 6:1 at a reaction temperature of 55°C. Under the given conditions, different biodiesel fuels and blends were successfully produced from the selected feedstock with properties very close to that of conventional AGO. They can therefore be commercialized for large scale utilization as biodiesel fuels or as blends with existing AGO which would be more environmentally friendly.