Bagasse, corncob and sawdust were used as lignocellulosic substrates for the production of cellulase enzyme using Aspergillus flavus after ballmilling and pretreatment with caustic soda. From the fermentation studies, sawdust gave the best result with an enzyme activity value of 0.0743IU/ml while bagasse and corncob gave 0.0573IU/ml and 0.0502IU/ml respectively. The three lignocellulosics gave their maximum enzyme activities at about the twelfth hour of cultivation, suggesting that the 12th hour is the optimum time when the enzyme may be harvested.

This study focused on the production of biodiesel via transesterification of refined soybean oil obtained locally. Sodium hydroxide was used as the alkali catalyst and methanol (as alcohol) was used in the transesterification process due to its low cost. The methanol-to-oil molar ratio was maintained at 6:1. The effect of reaction temperature with time and the catalyst loading were studied. The reaction temperature and the catalyst loading were varied at 30, 40, 50, 60 and 70 o C; and at 0.5 and 1.0% weight of oil, respectively. After transesterification of the soybean oil, the fatty acid methyl esters [FAMEs (biodiesel)] conversion was found to rise with an increase in the catalyst loading and also with the reaction temperature but no significant difference (P > 0.05) was found between the temperatures of 60 o C and 70 o C. The optimum methyl esters conversion of 97.89% was achieved at 60 o C for 3 h with 1% (w/w) catalyst. The viscosity (at 40 o C), density, cloud point, pour point, flash point and acid number were 3.40 cSt, 0.86 g/ml, -1 o C, -7 o C, 175 o C and 0.19, respectively. This optimum methyl esters conversion obtained met ASTM standard of D-6751. Therefore, soybean oil has been shown in this study as a good candidate for biodiesel production and the data acquired can be scaled up for large scale production.

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Literature on the oxidative pyrolysis of propane is very sparse for temperatures above 600 OC. Hence the present work was carried out between 600 and 700 OC at 1 atm total pressure using a plug flow quartz reactor and the MS10-C2 mass spectrometer as the analytical tool. Small amounts of oxygen were added into the propane stream such that the oxygen can only participate in the early stages of reaction, thus throwing some light on the nature of the initiation reactions in pyrolysis and oxidation systems. Results were compared with computer predictions. The following observations were made: (1) a faster rate of decomposition of propane in the presence of oxygen than in its absence; (2) a product distribution (at the initial stages) in order of magnitude C3H8, C2H4, CH,, H, , and C2Hs as compared to the order CH, , C2H4, C3H6, H, , and C2H6 in the absence of oxygen; (3) the mechanism reported in the literature for temperatures between 500 and 600 "C is also operative at higher temperatures; (4) a 28 reaction step model fits the experimental data. The role of H 0 2 in relation to the observed product spectrum is also fully discussed

The pyrolytic behavior of propane is followed between 600 and 800 °C with a view to elucidating the mechanism and kinetics. This is effected by continuous sampling of the pyrolytic products through an MS10-C2 mass spectrometer and the results are compared with computer predictions. Quantification of the products is done by resolving the superimposed mass spectra with the aid of a novel matrix-inversion program (written by the authors). The numerical integration program employed is based on the semiimplicit trapezoidal rule. A 19 reaction step model based on generation and interaction of free radicals is proposed with the appropriate rate constants and integrated. The main products are CH4, C2H4, C3H6, H2, and C2H6. The predictions fit well the experimental data giving an activation energy at 245 kj/mol and an overall reaction order of unity with respect to propane concentration.