The potential of telfairia pedata for liquid biofuel and soap production
Nyagah, Priscillah Kanyua
MetadataShow full item record
About two billion people around the world have no access to modern energy. More than 84% of Kenya population use kerosene for cooking and lighting therefore it is necessary to search for suitable alternatives to liquid and cooking fuels. In this study, oil extracted from Telfairia pedata Hook (Oyster nut) was transesterified in methanol using sodium hydroxide catalyst. Methyl ester obtained was characterized by GC-MS and further tested for fuel properties relative to conventional diesel fuels (automotive diesel and kerosene). The results identified linoleate, hexadecanoate and octadecanoate as the fatty acid esters in the methyl ester. The ester viscosity at (40o C) was in the range of 4.22±1.9 mm2/s for Telfairia pedata compared to 4.188 mm2/s for automotive diesel fuels. The flash point of the ester was much higher (127oC) than referenced diesel fuels (74oC) and they are within the European standard EN-14214 for biodiesel of >100oC. The density of Telfairia pedata ester was 0.8752 g/cm3of which was higher than 0.8621 g/cm3 automotive diesel and 0.7884 g/cm3kerosene respectively. The esters were further blended with automotive diesel in ranges of 5-70% on volume ratio. Blends of 20% biodiesel in 80% petroleum diesel demonstrated the most ideal properties with viscosity and density very close to that of pure petroleum diesel. The esters were further tested in a multi-wick stove following standard water boiling test (WBT) and their performance in terms of time to boil, heat transfer efficiency, power output and specific fuel consumption .The esters burnt with odorless and non pungent smell with mean thermal transfer efficiency of 45±0.5% compared to 50±0.5% thermal transfer efficiency of petroleum kerosene fuel. However, the ester demonstrated fire power of 1136±7.4W which was 19.2% much lower compared to that of kerosene fuel. Telfairia pedataester showed fuel properties very close to automotive diesel and thus could be used in diesel appliances without any modifications. Coconut esters on the other hand showed properties close to kerosene and gave stove performance characteristics almost similar to kerosene making it most favorable as bio-kerosene. An emission test was conducted to demonstrate suitability of the methyl esters (biodiesel) in reduction of CO emission in liquid fuel cooking stoves. The test system consisted of a stove platform an exhaust hood and a gas analyzer fitted with a non-dispersive infrared spectrometer system. All fuels emitted carbon monoxide; however T. pedata biodiesel fuel registered 53% less CO emission compared to kerosene fuel. Physiochemical analysis of extracted seed oil was carried out in order to justify its usefulness in soap industry. The following values were obtained for the various parameters measured; saponification 230.0±4.5 mg KOH/g, iodine value 109±1.0g I2/100g, acid value 1.0±0.1 mg KOH/g. The analytical values obtained were significant in favor of the utilization of the Telfairia pedata for soap production. The lather volume and total fatty matter were 25ml and 6.5% lower than that of coconut respectively. Coconut soap showed better results for soap making due to its abundant lauric acid present compared to T. pedata (lather volume 640 cm3 and 625 cm3 respectively) however the blends of the two showed better results than T. pedata oil ( Total Fatty Matter, 81.6% and 80.6% respectively).