The recently observed depletion in the petroleum resources, which also mainly constituted carbon ... more The recently observed depletion in the petroleum resources, which also mainly constituted carbon dioxide emission and global warming problems call for renewable and sustainable alternative fuels. Oils were extracted from various seeds: Jatropha curcas (Botuje), Pentaclethra macrophylla (Apara) and soybean, using petroleum ether (40-60℃). Alkali catalyzed transesterification of the oils (biodiesel production) in the presence of different kinds of alcohol (methanol, ethanol and propanol) were carried out using sodium hydroxide as catalyst. In the case of Jatropha oil, potassium hydroxide served as catalyst. Effect of catalysts to obtain optimum biofuel was established. In the case of soybean oil, fatty acid methyl ester, FAME, (96%), fatty acid ethyl ester, FAEE, (84%) and fatty acid propyl ester, FAPE, (37.50%) were produced. In waste palm kernel oil, methyl ester (72.92%) and ethyl ester (46.25%) were obtained. In refined palm kernel oil, methyl ester (70.83%), ethyl ester (66.67%) and (14.17%) propyl ester were produced. However, only methyl ester conversion (20.83%) was possible in Pentaclethra macrophylla oil. In Jatropha curcas using KOH catalyst, only methyl ester (80%) formation was possible. Moreover, yields were affected as the alcohol alkyl became bulkier giving relatively lower value of biodiesel. Sulphur content (0.01) obtained for each of the biofuel was satisfactory when compared with ASTM standard (0.05 maximum). The cetane value of soybean oil (45.5), refined palm kernel oil (46) and used oil (44.6) were quite reasonable compared with the special standard (47). The combustion energy of the fuels from refined palm kernel oil, waste palm kernel oil and soybean are 39, 36 and 45.5 respectively. The total glycerol content (Gc) of the methyl and ethyl esters emanated from soybean are quite reasonable and fell within standard.
Paint systems containing color-change or fluorescing compounds were found to be sensitive to unde... more Paint systems containing color-change or fluorescing compounds were found to be sensitive to underlying corrosion processes by reacting to the pH increase associated with the cathodic reaction that accompanies corrosion. The sensitivity of acrylic-based coating systems for detection of cathodic reactions associated with corrosion was determined by applying constant cathodic current and measuring the charge at which color change or fluorescence was detected. Unaided visual observation of coated samples detected changes resulting from a charge corresponding to a hemispherical pit with a depth of 10 µm. Characteristics of modified acrylic coating systems were studied by titration tests. Electrochemical impedance spectroscopy also was performed to test the influence of the indicating compound addition on the coating corrosion protectiveness. The time for color change was determined to be controlled by the sensitivity of the coating to pH increase, and not by the coating protectiveness.
Uploads
Papers by bill mowers