The avocado seed was used as a raw material for the production of biodiesel as an alternative to petrodiesel. The oil was extracted using a soxhlet extractor with n-hexane as the solvent and transesterified with methanol (5:1 oil to methanol ratio) using potassium hydroxide as catalyst in 15 minutes reaction time. The percentage yield of the purified biodiesel was 78%. The physical and chemical properties of the biodiesel on comparison to standard biodiesel and petroleum diesel indicated that it was of good quality. It had a relative density of 0.86, cetane number of 62.2, kinematic viscosity of 3.94cst. The economies of this extraction turns avocado seed from bio-waste to wealth.

This research work was conducted to demonstrate the mechanism of white board marker ink production using locally sourced raw materials such as charcoal and used lube oil. In the production of the ink, the charcoal served as a pigment, used lube oil served as the primary binder or resin, ethanol served as solvent and gum Arabic served as an additive. The charcoal was obtained from processing of Mango, Oil bean (Ugba) and rubber trees, which were further crushed to their finest particles respectively and the used lube oil was obtained from mechanical engineering servicing unit of automobile engines. The crushed charcoal samples were characterized to determine the physio-chemical properties of some mineral elements such as Ca, Cu, P, K, C, S, N. however the mineral component that controlled the production of this ink was the Carbon content. The different ink samples were formulated in terms of odour, colour, hazardous reaction, pH, density and viscosity and compared with that of international standards. Results obtained showed a good match, indicating the reliability and the quality of the produced white board marker ink. The pH results for Ugba ink = 5.43, Rubber ink = 6.79, and Mango = 7.41. Empirical models were used to predict concentration with that of experimental values, a plot of concentration against time in terms of production yield revealed that the order of magnitude was rubber>Ugba>Mango whereas in terms of penetration and writing ability Ugba>rubber>mango. Furthermore, the research demonstrates the significance of the characteristics of the charcoal and the used lube oil in the quality of the end product. Finally, the research revealed that ink produced from the oil bean (ugba) charcoal and lube oil was best in terms of write-ability and quality in the production of white board marker ink.

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Predictive models for process parameters during regeneration of spent catalyst in an industrial fluid catalytic cracking (FCC) unit are presented. The models adopt a twophase theory where the dense region of the regenerator is divided into a bubble-phase and an emulsion-phase. The bubble-phase is modelled as a plug flow reactor, while the emulsion-phase is modelled as a continuous stirred tank reactor (CSTR). Profiles for regenerator-temperature, quantity of coke burnt, and flue gas composition, at different operating conditions are also presented. Model-predictions are compared with plant data and good agreement is obtained. Simulation results indicate that inlet-air velocity and catalyst-bed height have significant influence on the performance of the rege nerator. The model-estimated optimum operating conditions of the regenerator are regeneratortemperature of about 1000 K, inlet-air velocity of about 13.5 m/s, and catalyst-bed height of 13 m.

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