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An experimental study has been carried out on an alternative source of energy from citrus peel waste. A widely used material, pectin, has been extracted from orange peel (OP) and subsequently converted into ethanol with the use of a bacteria and fungi. Dried peels were split into several particle sizes of 0.075, 0.5, 1.0 and 5 mm. It was noted that OP with 0.75 mm particle size produced pectin of low volume while larger 1.0 mm OP particle size produced a high pectin volume. OP of 802 g was used to produce 1, 770 ml of pectin, this illustrate that citrus fruit (specifically orange) contains pectin in a large quantity. A mixture of E.coli (bacteria) with yeast (fungus), and their individual components were used on pectin obtained. However, it was observed that a mixture of pectin, E.coli & S. cerevisiae, and a combination of sample pectin with E.coli produced an encouraging volume of ethanol as against no ethanol produced when a mixture of sample pectin, yeast and pectin sample only. The amount of energy contained in the gross ethanol produced was 1526.6 btu, this can be combined with purified gasoline so as to attain the optimum energy content that can be used to run an indigenous processing plant for citrus fruit in Nigeria.

The optimum conditions for the fermentation of a local legume known as African locust bean (Parkia biglobosa) into a vegetable protein based food condiment or spice (Iru) were developed using Levenberg-Marquardt (or Powell) method (using PSI software) with three (3) variables namely; inoculum concentration (bacillus subtilis), temperature and the fermentation duration. P. biglobosa seeds were fermented at various temperature of 40 - 70 °C for five days (120 hours) with different concentrations of Inoculum. The proximate analysis shows that fermentation increased the percentage protein. Protein had the highest composition with about 51 % after 72 hours at the lowest fermentation temperature of 40°C.

Most papers are made from virgin wood-based pulp of hardwood sources but recently, softwood have received enormous attention as alternative to hard wood because the hardwood takes a significant number of years to mature enough for use in the pulp and paper industry unlike softwood which are majorly annual plants. The annual crop in focus in this work is the yellow open-pollinated variety of corn which generates tons of waste at harvest. A novel attempt is made to ascertain the viability of corn sheaths as raw material for the pulp and paper industry by carrying out a comprehensive analysis on the pulp and paper made from the pulp. The sheaths were dried, shred and cut into pieces suitable for the digester and the pulps obtained were analysed for physico-chemical properties. Hand sheets were also made using the generated pulp and its physico-mechanical properties were analysed. Results obtained were compared with pulp from corn husks from other parts of the country, three Nigerian fibre sources – silk cotton, bagasse and rice straw and other foreign non-wood sources and found to be of competitive properties. Pulp properties of Lignin content, ash content, cellulose, hot and cold water solubility of the fibres were 13.72 ± 1.21%, 1.27 ± 0.23%, 53.26 ± 1.11%, 15.20 ± 2.11 and 6.14 ± 2.43 respectively while the mechanical properties of paper from the pulp were Bursting strength (282.163 KPa m2/g), Tear strength (146.119), Tensile strength (257.6N/m) and Tensile Index (3.9Nm/g). It was found that in all properties, the corn sheath was better than the rice straw fibers but not as good as the silk cotton and bagasse fibers. However, the corn sheath has been identified, as a viable raw material for the pulp and paper industry in Nigeria.

Studies on the epoxidation of rubber (Hevea brasiliensis) seed oil, a renewable source with formic acid was performed in the presence of 30% hydrogen peroxide at a of temperature 40, 50, 60, 70 °C. The process is favoured by an increase in temperature forming a product with high oxirane content which is as a result of mole ratios of formic acid and hydrogen peroxide. Products of high oxirane content are commercialy viable in the production of polyvinyl chloride (PVC). Natural rubber and other products can be obtained from this in- situ technique. Studies in this research shows that the rate of epoxidation increases with an increase in temperature.Oxirane values of 2.30, 3.62 and 4.73 for the various temperature. However high oxirane content of 6.22 was obtained at 70 °C which is in line with literature. FTIR analysis was also carried out on the epoxidized rubber seed oil which shows the peaks of oxirane cleavage.

This study involves the extraction of oil from three sources: orange peel, guava leaves, and cassia fistula leaves using Soxhlet apparatus. The variables considered in this study were time of extraction and sample weight. Minitab statistical software was used to randomize the runs. The combination of operating parameters that gave the optimum yield for the three sources were identified. The regression equation for each source was reported. The coefficient of determination (R2) value for orange, guava leaves and cassia fistula extract were 99.51%, 99.90%, and 99.77% respectively. This shows that the model is a good prediction tool for extraction of oil from these sources. Based on the R2 values guava leaves (99.90%) gave the highest prediction accuracy followed by Cassia fistula (99.90%), with orange leaves having the lowest R2 value (99.77%) among the three sources considered.

The effectiveness of remediating soils polluted with crude and treated hydrocarbon oil using a fungi - Aspergillus niger, bacteria - Pseudomonas aeruginosa and the combination of the two were investigated and the first order kinetics were studied. Eight systems of 500g soil sample were polluted with both raw and treated crude oil. Four systems were polluted with 100 ml treated crude oil while other remaining systems with same quantity of raw crude oil. Two systems with raw and treated crude oil were left as control (RCC and TCC). Samples of soil polluted with raw crude oil were amended with A. niger (RCA) and P. aeruginosa (RCP) respectively, while treated crude samples were also treated with same (TCA) and (TCP) only. The last two systems were treated with both P. aeruginosa and A. niger (RCAP and TCAP). First order bioremediation kinetics and biostimulant efficiency for these systems were studied by monitoring Total Petroleum Hydrocarbon (TPH). The result obtained at the end of the bioremediation period, revealed that treated crude oil polluted soil remediate faster and better than raw crude oil polluted soil. The highest level of bioremediation occurred in systems amended with both A. niger and P. aeruginosa which had about 98 % TPH decrease.

The anaerobic digestion process for biogas production was investigated on food waste (FW) and cow dung (CD) using Pseudomonas aeruginosa as inoculum. The food waste and cow dung were co-digested as the substrate with bacteria (P. aeruginosa). Five digesters were prepared to observe the maximum gas production potential, methane production rate and duration for biogas production. Food waste (FW) was co-digested with bacteria in two proportions (1:5ml, 1:10ml) and co-digested with Cow dung (CD) in two proportions (1:1, 1:0.5). The digesters were all operated in batch process under mesophilic condition (35ºC). The daily weights of the tubes were measure and some physical characteristics of the substrate were determined before and after the process. Production of gas started 3-4 days after commencement for the digesters with cow dung, 4-5days for the digesters with bacteria and 3 days with only food waste. Food waste with 1kg, cow dung produced the most biogas with a cumulative volume of 88.5g/kg. The highest concentration of biogas was found in the 1st digester consisting of 2kg CD and 2kg FW with a methane content of 52% and 48% CO2. The availability and renewable nature of food waste, ease of management of biogas produced and development of energy makes biogas a better option than the use of fossil fuel to the much-awaited solution to the energy crisis in Nigeria and developing countries.