DEPARTMENT OF CHEMICAL ENGINEERING

This study focuses on the production of biodiesel from waste cooking oil (WCO) using calcined cow bone as a heterogeneous catalyst through the transesterification process. The research aimed to promote sustainable energy production by converting waste oils into biodiesel while utilizing animal bone waste as a low-cost, environmentally friendly catalyst. The WCO was pretreated and characterized to determine its physiochemical properties, which included an acid value of 1.4025 mg KOH/g, free fatty acid (FFA) content of 0.7012%, peroxide value of 16 meq/kg, iodine value of 44.1 g I₂/100 g, viscosity at 40 °C of 53.5 cP, saponification value of 362.667 mg KOH/g, moisture content of 2.678%, and density of 0.9176 g/cm³. These results confirmed that the feedstock required pretreatment before transesterification to minimize soap formation and enhance biodiesel yield. Characterization of the catalyst was performed using analytical techniques such as X-ray fluorescence (XRF), Brunauer–Emmett–Teller (BET) surface area analysis, and Fourier transform infrared spectroscopy (FTIR) to confirm the presence of CaO and evaluate its surface properties.The transesterification reaction was carried out using methanol and cow bone-derived catalyst under optimized conditions. The resulting biodiesel was washed, purified, and analyzed for key physiochemical properties. The biodiesel exhibited an acid value of 0.561 mg KOH/g, density of 0.901 g/cm³, viscosity at 40 °C of 8.86 cP, and a flash point of 115 °C. These results were within acceptable limits prescribed by ASTM D6751 and EN 14214 standards, indicating that the produced biodiesel possesses good fuel properties suitable for use in diesel engines. The study concludes that waste cooking oil can serve as an efficient feedstock for biodiesel production, and cow bone ash is a promising, sustainable, and economical catalyst. This dual utilization of waste materials not only reduces environmental pollution but also supports circular economy practices and sustainable energy development.

Palm Oil Mill Effluent (POME) is a wastewater byproduct of palm oil production, characterized by its high organic content and potential pollutant to water bodies and capable of causing significant environmental damage. This study therefore seeks to evaluate the treatment methods by coagulation and adsorption processes to remove suspended solids and pollutants, thereby purifying the wastewater for safe discharge or reuse. These methods are essential for environmental protection, resource recovery, and economic sustainability. The POME sample was collected, diluted, and analyzed to determine its physicochemical properties before treatment. Its pH was adjusted to both acidic and alkaline conditions using hydrochloric acid and sodium hydroxide, monitored with pH indicator paper. Processed periwinkle shell powder served as a natural coagulant and adsorbent. Standard laboratory instruments were used to assess parameters such as pH, turbidity, total dissolved solids, electrical conductivity, and salinity before and after treatment. The study evaluated the effects of coagulant dosage, contact time, and pH on the treatment of Palm Oil Mill Effluent (POME) using a periwinkle shell–chitosan composite. Significant reductions in total dissolved solids (TDS) and salinity were achieved at moderate dosages (0.55– 0.82 g/L), contact times of 105–150 minutes, and near-neutral pH (7–8.2), showing effective coagulation and adsorption. X-ray diffraction (XRD) analysis revealed crystalline peaks at 2θ values of 23.9°, 26.5°, 27.5°, 33.4°, 36.4°, 38.1°, 41.4°, 43.1°, 46.0°, 48.6°, 50.5°, and 53.1°, corresponding to aragonite, muscovite, quartz, and orthoclase phases. Crystallite sizes (111–702 Å) confirmed a fine heterogeneous structure with high surface activity, making the composite suitable for efficient and sustainable POME purification

This research investigates the feasibility and performance of polymer flooding as an enhanced oil recovery (EOR) method for Nigerian sandstone reservoirs. With the growing need to improve oil recovery from mature fields and reduce dependency on primary and secondary recovery techniques, polymer flooding has emerged as a promising tertiary recovery strategy. The study focuses on evaluating the technical and operational effectiveness of injecting hydrolyzed polyacrylamide (HPAM) polymer solution under representative Nigerian reservoir conditions using the CMG-STARS simulation software. A detailed reservoir model was developed, incorporating a six-layer sandstone formation characterized by an average porosity of 20%, initial pressure of 2299.2 psi, and oil viscosity of 5 cP. Two simulation cases were analyzed: a base case (without EOR) and a polymer flooding case with a 2000 ppm polymer solution injected over a 30-year production period (2025–2055). The performance of both scenarios was evaluated based on field oil production rate, bottom-hole pressure, water cut, and cumulative oil recovery. The results revealed that polymer flooding significantly improved reservoir performance compared to the base case. While the base case exhibited a steady decline in pressure and oil rate leading to early depletion around 2047, the polymer injection maintained an average pressure of about 2100 psi throughout the simulation. The polymer case also achieved a cumulative oil
recovery of 23.6 million stock tank barrels (MMSTB), representing an incremental gain of 5.8 MMSTB (32.6%) over the base case. Furthermore, water cut was reduced from 89% to 68%, indicating better mobility control and sweep efficiency. These findings confirm that polymer flooding is a technically viable and cost-effective EOR method for Nigerian sandstone reservoirs, capable of improving oil displacement efficiency and extending field life. The study recommends that field pilot projects be implemented to validate simulation outcomes and optimize polymer formulation for local reservoir conditions. Overall, this research demonstrates that polymer flooding can play a vital role in maximizing Nigeria’s oil recovery potential, supporting energy sustainability, and promoting efficient reservoir management.

Ikpoba River is the major recipient for municipal waste and industrial effluent in Benin City,samples of water were collected at five different locations in the river for some selected heavy metal analysis in order to determine the extent of pollution. Samples were collected in August to December 2021. Chemical analyses of samples river water and Dam was collected at predetermined sampling points were undertaken, the observations obtained were subjected to ANOVAand correlation analysis. Results obtained showed that each point source has its relative contribution to the overall degradation of the river water quality. The heavy metals were determined with atomic absorption spectrophotometry (AAS). From river water and dam the heavy metal concentrationwere found to be in the increasing order, fe>zn>cu> pb>Cd for all the five samples point collection as show in the result analysis. It also shows that the lead was not present in one of the point and Cadmium were not also detection in all of five sample. The analyses carried out also show the level of phosphate, nitrate, magnesium, pH, BOD,DO, electrical conductivity and turbidity in all the five stations and the turbidity was also notice to be relatively high. Most of the heavy metal determine were below the maximum permissible limit set by FEPA and WHO

The extensive use of synthetic fertilizers in agriculture has led to environmental concerns, necessitating the exploration of sustainable alternatives. Thisstudy investigates the optimization of organic fertilizer production from neem leaves (Azadirachta indicd) and evaluates its efficacy on maize (Zea mays Ld) growth and yield. This research determined the impact of drying temperature on the nutrient composition of neem leaf powder and established the optimal application rate for maize cultivation. The findings demonstrate that drying temperature significantly influenced the fertilizer's nutritional quality. While potassium content remained stable, nitrogen and phosphorus concentrations decreased markedly at temperatures exceeding 45°C, with losses exceeding 20% and 13%, respectively, at 65°C. Consequently, mild drying (< 45°C) was identified as the optimal processing parameter. In a field experiment using a Randomized Complete Block Design (RCBD), the application of the optimized neem leaf powder at 120 kg ha -1 resulted in the most significant improvements, enhancing soil pH, organic carbon, and available NPK. This treatment also produced the highest maize grain yield of 4.58 t ha -1 , a 90% increase over the unfertilized control, alongside superior plant height and a reduced anthesis-silking interval. The study concludes that NEEM processed by means of air-drying represents a viable, sustainable organic fertilizer source capable of replenishing soil nutrients depleted by maize production, offering environmental and economic benefits for small-scale farmers in tropical agricultural systems.

Palm Oil Mill Effluent (POME) is a wastewater byproduct of palm oil production, characterized by its high organic content and potential pollutant to water bodies and capable of causing significant environmental damage. This study therefore seeks to evaluate the treatment methods by coagulation and adsorption processes to remove suspended solids and pollutants, thereby purifying the wastewater for safe discharge or reuse. These methods are essential for environmental protection, resource recovery, and economic sustainability. The POME sample was collected, diluted, and analyzed to determine its physicochemical properties before treatment. Its pH was adjusted to both acidic and alkaline conditions using hydrochloric acid and sodium hydroxide, monitored with pH indicator paper. Processed periwinkle shell powder served as a natural coagulant and adsorbent. Standard laboratory instruments were used to assess parameters such as pH, turbidity, total dissolved solids, electrical
conductivity, and salinity before and after treatment. The study evaluated the effects of coagulant dosage, contact time, and pH on the treatment of Palm Oil Mill Effluent (POME) using a periwinkle shell–chitosan composite. Significant reductions in total dissolved solids (TDS) and salinity were achieved at moderate dosages (0.55– 0.82 g/L), contact times of 105–150 minutes, and near-neutral pH (7–8.2), showing effective coagulation and adsorption. X-ray diffraction (XRD) analysis revealed crystalline peaks at 2θ values of 23.9°, 26.5°, 27.5°, 33.4°, 36.4°, 38.1°, 41.4°, 43.1°, 46.0°, 48.6°, 50.5°, and 53.1°, corresponding to aragonite, muscovite, quartz, and orthoclase phases. Crystallite sizes (111–702 Å) confirmed a fine heterogeneous structure with high surface activity, making the composite suitable for efficient and sustainable POME purification

The global petroleum industry faces continuous and costly challenges in resolving stable water-in-oil (W/O) emulsions, a process that traditionally relies on expensive, non-biodegradable synthetic demulsifiers. This study investigated the development and optimization of a sustainable, bio-based demulsifier derived from a synergistic blend of extracts from Citrus sinensis (orange) and Musa spp. (banana) peels, aiming to provide an environmentally responsible alternative. The demulsifier was prepared via solvent extraction of the agricultural waste. Characterization showed the blended formulation possessed an optimal pH of 5.8 and a density of 998.0 kg/m³. Chemical analysis using Fourier-Transform Infrared Spectroscopy (FTIR) confirmed the presence of non-ionic, amphiphilic functional groups (O-H, C-H, and C-O), indicative of a surfactant-type demulsifier system4. The demulsification performance was optimized using Response Surface Methodology (RSM), analyzing the interactive effects of demulsifier dosage, temperature, and demulsification time to maximize the final water cut percentage. The resulting quadratic model demonstrated a strong correlation and predictive power, indicated by an excellent Coefficient of Determination (R²) of 0.9768. The synergistic blend achieved a peak demulsification efficiency under the tested conditions, with the maximum recorded water cut being 20 v/v%. This efficiency is attributed to the complementary action of the constituent compounds: the lipophilic D-limonene (C. sinensis) acts as a solvent to weaken the interfacial film, while the hydrophilic saponins and phenolic compounds (Musa spp.) competitively adsorb at the interface to promote rapid droplet coalescence.

Heavy metals are classified as hazardous chemical substances. They are major environmental pollutants and these pollutants affects the welfare of the environment, reduces the quality of life and eventually causes death. They are a collection of metal sand metalloids that have an atomic density larger than 4 g/cm3. A major source of Pb(II) pollutant is the automobile battery waste in automobile worship. This study was done to investigate the transport of Pb (II) in soil using response surface methodology. This investigation was carried out using a packed bed, which is a cylindrical vessel filled with uncontaminated sand. The bulk density, porosity, moisture content and pH of the soil were determined using standard procedures. The soil was then contaminated with stock solutions of Pb (II). A two - level, two - factor central composite design (CCD) was used for the design of the study. The factors considered for this study were depth and time while the concentration of Pb (II) was the response. The concentration level of Pb (II) at each point was determined using the atomic adsorption spectrophotometer (AAS). The results showed that the transport of heavy metals in soil is greatly influenced by the physico – chemical properties of the soil. The time factor had only a marginal
effect on the concentration level of Pb (II) while an increase in depth showed a significant decrease in Pb (II) concentration. The optimum concentration level was found to be at 30cm deep, after 36hrs of contamination. The findings from this investigation shows that time and depth of the soil is the predominant factor in the transport of Pb (II) on packed bed

This study investigated the effect of process parameters, temperature, hydrolysis time, and acid concentration in the pretreatment of cassava peels and sawdust on sugar yield. The pretreatment steps were performed using the Box Behnken full factorial of a central composite design (CCD) in a response methodology (RSM) with DESIGN EXPERT. Dilute acid was applied in the pretreatment process to enhance the generation of fermentable sugar yields by the DNS method. Forty six (46) experimental runs were carried out at parameters range of; temperature (30 – 100°C), HCl concentration (1 – 5%w/w), and time (15 – 90 mins). The concentration of the reducing sugar produced for each was used to study the effect of variation of process parameters. The results reveal that temperature, time and acid concentration significantly affected sugar yield. The optimum amount of the reducing sugar yield 6327.77 mg/L was obtained at 5/5g, 65°C, 52.5min, 3%w/w.

This study aims to optimize the extraction of bioactive compounds from guava leaves using the Soxhlet extraction method to investigate the impact of key variables such as mass of the solvent, temperature and extraction time (hours) on the bioactive extraction yield, to characterize the extracted bioactive compounds to identify key functional groups, and to optimize the bioactive yield. The study employed a central composite design (CCD), with 19 experimental runs where Response Surface Method (RSM) was utilized to optimize extraction conditions, evaluating the effects of mass (1.00-10.00 g), extraction time (30-300 min), and temperature (50-90°C). ANOVA and quadratic regression models assessed the influence of these variables on the yields of terpenoids and flavonoids. The qualitative and quantitative analysis of extracted compounds was conducted using colorimetric chemical tests and FTIR spectroscopy. Statistical validation included model significance testing (p-values), R², adjusted R², predicted R², and adequate precision. The qualitative analysis of guava leaf extract identified flavonoids (yellow), terpenoids (reddish- brown), saponins (froth), alkaloids (reddish-brown precipitate), and tannins (greenish-black). Quantitative results showed the highest percentages in flavonoids (15%) and terpenoids (16%), followed by saponins (2%), alkaloids (1.75%), and tannins (0.183%). Extraction efficiency was highest at intermediate conditions, with significant quadratic effects observed for all three independent variables. The regression models yields for the two major extract, terpenoid and flavonoid, demonstrated high accuracy with R2 is 0.7915 for terpenoid and R² = 0.8957 for flavonoid, with ANOVA confirming model significance (F-value = 0.17, p = 0.9585) and (F- value = 8.59, p = 0.0019) for terpenoid and flavonoid respectively. Also, the extraction yield was significantly affected by mass, time, and temperature. Terpenoid yield declined beyond 55 g and 165 min due to solvent saturation, while flavonoids degraded above 70°C. Optimal conditions enhanced solubilization and diffusion, but excessive parameters caused thermal degradation, volatilization, poor solvent penetration, and reduced extraction efficiency. These findings support guava leaves as a rich source of bioactive compounds with antioxidant, anti- v | P a g e inflammatory, and antimicrobial properties, valuable for pharmaceutical and nutraceutical applications.