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Biodiesel is an alternative diesel fuel consisting of the alkyl monoesters of fatty acids from vegetable oils or animal fats. Biodiesel is a promising alternative fuel derived from animal fats or vegetable oil through transesterification with methanol. Base catalyzed transesterification is the most commonly used technique as it is the most economical process. Presently, a lot of heterogeneous catalysts have been formulated that are more effective than the homogeneous catalysts. CaO/Al2O3 was synthesized using incipient wetness impregnation method. The biodiesel was developed and optimized using Box-behnken response surface methodology (RSM) design provided using MINITAP-17 statistical software. The four independent variables considered are: reaction time, methanol to oil ratio, reaction temperature and catalyst concentration. The response chosen was fatty acid methyl ester (FAME) yields which were obtained from the reaction. The result from analysis of variance (ANOVA) showed a satisfactory result. Moreover, the input variables showed greater significance on the response which are reaction time and temperature base on F and P-value. The statistical models developed for predicting biodiesel yield revealed a significant agreement between the experimental and predicted values (R = 0.9686). An optimum methyl ester yield of 93.29 % was achieved with optimal conditions of methanol/oil molar ratio of 6:1, temperature of 600C, reaction time of 120 min and catalyst concentration of 1.0 wt%. The properties of the biodiesel produced also falls within the range prescribed by ASTM standard

The growing concerns about global warming and depleting petroleum reserves have made scientists/researchers focus more on the use of natural fibres such as Maize cob, bagasse, coir, sisal among others. About 180 kg of cobs are obtained from each ton of maize shelled which has little utilization or no utilization. This study utilizes maize cob from SAMMAZ-14 maize variety for the extraction of nano cellulose using Chemico-mechanical method. Alkaline hydrolysis was performed with 5% NaOH for 4hrs with MLR of 1:10. Ball milling was done for 5 hrs with BMR of 30:1. The extracted nanocellulose were characterized by thermal characterization (TG and DTG), field emission scanning electron microscopy (FE-SEM), Energy Disperse X-ray (EDX) and atomic force microscopy (AFM), which confirmed the extracted Maize cob nano fibres (MC-NF) were in nano scale ranging from 1-100 and 1-200nm in diameter and length respectively. Thermal analysis showed MC-NF has more thermal stability than untreated maize cob (MC-UT) whose degradation was initiated at lower temperature with higher charred formation. Morphological studies showed MC-NF has spindle like structures while the untreated maize cob (MC-UT) is plain due to high amorphous portion on the cellulosic structure.

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A silane coupling agent is an organosilicon compound with special structure possessing organic functional groups and hydrolysable groups. In this study, a superhydrophobic-superoleophilic nano-silica film on ceramic membrane was constructed by a modified Stöber technique by using tetraethoxy-silane (TEOS) and fluoroalkyl silane (FAS). The colloidal nano-silica based silane sol coating solution was synthesized via co-hydrolysis and co-condensation of TEOS and FAS. Particle size distribution of the colloidal nano-silica based silane sol was evaluated using particle size analyzer as depicted. The contents of the relative elements of the colloidal nano-silica based silane sol were examined using energy dispersive x-ray (EDX) spectra. Extent of superhydrophobicity-superoleophilicity was determined using the contact angle measurements. The surface wettability of superhydrophobicity-superoleophilicity was determined using the contact angle measurements. Also, the effects of grafting times and coating cycles on the wettability of the modified kaolin-based hollow fiber membrane were determined. The results revealed that the modified kaolin-based hollow fiber membrane exhibited oil contact of 0o and water contact angle of 160o and, demonstrating its considerable antiwetting applications like in oil-water filtration process. While, with an increase in grafting times and coating cycles, the wettability of the superhydrophobic-superoleophilic nano-silica film was enhanced due to increase in surface roughness provided by the hydrolysable groups on the surface of the ceramic membrane. In conclusion, this study presents a feasible route to the surface superhydrophobicity-superoleophilicity testing of ceramic membranes