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The complex and ordered arrangements of the lignocellulosic materials make them recalcitrant for their conversions to ethanol. Pretreatment is a crucial step in overcoming these hindrances. In this study, a 23-full factorial design of experiments optimization technique was applied on the alkaline peroxide oxidation pretreatments of rice husks biomass. The low–high levels of the influencing variables on pretreatments were; temperature (100–120 °C), time (1–2 h), % (v/v)H2O2 concentration (1–3%). Under the prevailing pretreatments, the optimum conditions were predicted and validated to be 109 °C, 2 h, and 1.38% H2O2 which yielded 56% (w/w) cellulose content, 55% (w/w) hemicellulose solubilization, and 48% (w/w) lignin removal. At the established optimum pretreatment conditions, and considering variations in biomass and enzymes loadings, maximum reducing sugars production was 205 mg/g dry biomass at different enzymatic hydrolysis conditions of 3% biomass loading, hydrolysis temperature of 45 °C, hydrolysis time of 24 h, and 35 FPU/g cellulose enzyme loading. The highest cellulose conversion of 33% yielded 24 g/L ethanol at the end of the first day of saccharification and fermentation. Physical, structural, and morphological investigations on raw and treated materials using tools such as stereomicroscopy, scanning electron microscopy, and fourier transform infrared spectroscopy further revealed the effectiveness of chosen method on rice husks biomass.

In this research work, the comparative analysis of the production of high yield and environmental friendly biodiesel obtained from the transesterification of waste soybean oil, using technical grade CaO catalyst and CaO catalyst derived from chicken eggshells, was investigated. The results of the transesterification process, SEM (using ME 600T polarising optical microscope) and XRF (using Thermo Scientific ARL OP-TIM’X 166) analysis revealed a similar catalytic performance trend when the two forms of the CaO catalysts were used separately. For technical grade CaO catalyst (using response optimizer), the optimal conditions established for the production of biodiesel were methanol/oil mole ratio of 7.1, catalyst concentration of 5.9 wt/wt% oil and reaction time of 2.1 hours, with 92.6% biodiesel yield. Using CaO catalyst derived from chicken eggshells, the optimal conditions were 7.0 methanol/oil mole ratio, 6.0 wt/wt% catalyst concentration and reaction time of 2.2 hours, with 91.4% biodiesel yield. Impact assessment of the biodiesel production was carried out using ReCiPe Endpoint (E) V1.12/World ReCiPe E/E method (SimaPro 8.0 software) and AAnalyst 200 Perkin Elmer (AAS). The results of the impact assessment showed that technical grade CaO catalyst has more negative impact on human health and a lesser impact on ecosystems. In contrast, CaO catalyst derived from chicken eggshells waste has a fairly lesser negative impact on human health and a fairly more pronounced negative effects on ecosystems.

The effects of frying unripe plantain and sweet potato (separately) in soyabean oil on the properties of the oil were investigated. Also, the effect of the degradation of the oil on biodiesel yield obtained from the oil was considered. Physico-chemical properties of soyabean oil (acid value, saponification value, viscosity, density, colour) were measured daily after being used for frying for days. The fatty acid profile of the oil was analysed daily using GC/MS and biodiesel was produced daily from the oil sample. The results of the frying process showed increase in oil Acid values in the two cases; sweet potato (1.10 – 1.16mgKOH/g) and unripe plantain (1.12 – 1.71mgKOH/g). And increase in oil saponification values (146 – 271mgKOH/g for sweet potato and 175 – 340mgKOH/g for unripe plantain). The oil became less dense, less viscous and darker in colour for both batches during repeated frying. Five day Frying process reduced the percentage unsaturated fatty acid contents of oil (for unripe plantain from 81.94% to 36.80% and for sweet potato from 82.46% to 40.10%) and increased the percentage saturated fatty acid composition of the oil (unripe plantain from 12.18% to 34.70% and sweet potato from 12.24% to 27.50%). As frying progress, there was reduction in biodiesel yield, though insignificant difference in yield was observed between the biodiesel obtained from unripe plantain frying process and that obtained from the sweet potato frying process

The research work investigated the production of adhesive from cassava starch. Cassava tubers were processed into starch-based adhesives, using two different gelatinization enhancers (that is HCl and NaOH) which were introduced separately. The adhesives were produced by considering two varied process parameters, namely percentage weight of borax in starch solution (8 – 20%) and reaction temperature (65 – 85°C). Comparative analysis of the adhesive obtained (using HCl and NaOH as gelatinization enhancers) include the determination of its bond strength, viscosity, drying time, pH and density. As the borax weight percent increases up to 14 % and reaction temperature reduces (using NaOH) the drying time increases, while the drying time reduces as both the borax weight percent and temperature reduce (using HCl). The results of the adhesive physical properties fall within the standard range for each of the properties and this implied that the adhesive produced was of high quality.

In this study, alkaline peroxide oxidation pretreatment was evaluated for sugarcane bagasse, a lignocellulosic biomass. By comparing the effects of NaOH- H2O2 and Ca(OH)2 on pretreatments at specified reaction time periods (3, 6, 9, and 12 h) and reaction temperatures (60, 70, 80, and 90 h), optimum responses in term of cellulose content, hemicellulose solubilization, and lignin removal were established. Optimum pretreatment conditions of 80 o C reaction temperature, 3 h reaction time, and 30 mL/L of water hydrogen peroxide concentration (1%H2O2) solubilized 69.5%(w/w) hemicellulose for the sodium hydroxide peroxide (SHP) pretreatments, 75.8%(w/w) lignin removal was also achieved with 59.2%(w/w) cellulose retained in the solid fraction. In addition, the responses for the optimum conditions for the calcium hydroxide peroxide (CHP) pretreatments, the cellulose content, hemicellulose solubilization, and lignin removal were 50.3%, 66.6%, and 65.4%(w/w) respectively. Pretreatments showed both NaOH- H2O2 and Ca(OH)2-H2O2 to be useful pretreatment agents for the disruption of the polysaccharide complex. The study also revealed that NaOH-H2O2 pretreatment stands as a better choice to Ca(OH)2-H2O2 pretreatment.

The use of vegetable extracts as milk coagulants has evolved recently in soft cheese processing. In this study, two types of cheeses were produced from locally sourced raw cow milk using two different coagulants, Calotropis procera leaf and CaCl2. Protein, fat, Zn, Mg, and Fe were the nutrients and minerals that were assayed. The protein (18.4%), Fat (7.93%), Mg (4.13%), Zn (4.01%), Fe (2.59%) of Calotropis procera coagulated cheese was significantly higher than CaCl2 coagulant produced cheese with protein content of (9.13%), Fat (5.53%), Mg (2.34%), Zn (2.59%), Fe (1.13%). The higher ash content in the cheese produced with CaCl2 coagulant makes it susceptible to microbial growth, as a result, reducing its shelf-life. The study suggests that cow milk and Calotropis procera produced cheese appears promising in nutritional contents with further quality improvement.