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Some organic pollutants change the color, smell, and other characteristics of water leaving it undesirable for use. However, other organic pollutants do not change the physical properties of the water, yet, they make the water non-useful. This study was carried out to determine the characteristics of petroleum contaminated water and how it can be purified using economical filters for possible reuse in rural areas of the Niger Delta, of Nigeria. The filters were made from rice husk ash, and white clay, as main materials, while calcium carbonate and poly (propylene carbonate) were used as binders and pore former. The water samples were tested for conductivity, turbidity, pH, heavy metals, and total hydrocarbon contents. The results showed a significant decrease in the amount of petroleum/organic pollutants present in the water sample before purification. The filter candle made using poly (propylene carbonate) as a binder was found to be the most efficient in removing organic pollutants, but it was not very effective in the removal of heavy metals and also, the pH of the filtrate became more acidic. Filtrates from other filters, however, had pH in an acceptable range. Dodecanoic acid and hexadecanoic acid were found to be removed from the polluted water using the filters.

Trace metals when present in crude oil or fuels are of economic significance in refining and to the combustion engines that use them. Herein, we develop a laboratory activity that trains students on how to analyze crude oil samples for ash and trace metal content while giving them the opportunity to acquire skills needed as a quality control analyst in the industry. Students were divided into three groups and were trained on sample preparation, standard preparation, and quantificational and operational use of the flame atomic absorption spectrophotometer. Each group after preparing their samples quantified the concentration of Pb, Cu, Ni, Zn, and Mn in crude oil samples. The discussion over the results enabled the students to draw inferences on the sampling methods, and ways to improve precision and accuracy in instrumental analysis.

Isoberlinia dokasawdust; an abundant waste material was pre-treated using FeCl3, HCl, NaOH, sequential HCl and NaOH treatments at 121 °C for 15 min to mitigate the challenges of its utilisation as a carbon source for bioethanol production. The effects of these treatments on the biomass were evaluated using Fourier transform infrared (FTIR) spectroscopy and gravimetric methods. The capability of the pre-treated residue to produce fermentable sugars and bioethanol were also assessed. The treated biomass were saccharified using cellulase mix from Aspergillus nigerand Trichoderma reesiand fermented using Saccharomyces cerevisiae. The result shows that the chemical treatments significantly (p< 0.05) diminished the lignin contents and improved cellulose content of the treated samples; evident from decreased FTIR spectral intensities related to lignin. The cellulase mixture efficiently digested the treated biomass and resulted in significant (p< 0.05) sugar yield compared to the untreated biomass. Although the sequential HCl and NaOH treatment had the highest reducing sugar yield (280.1 mg/g), its ethanol yield (172.2 mg/g) was low, possibly due to formation of inhibitory bye-products. The alkali treatment reduced the lignin content and resulted in the highest ethanol yield (230.7 mg/g). Isoberlinia dokasawdust demonstrated great potential to be used as a sustainable feedstock for bioethanol production.

Bioethanol is an environmentally friendly alternative to petroleum energy sources. This study evaluated the effects of H2O, HCl, NaOH and FeCl3pretreated rice husk feedstocks on the production of bioethanol. The pretreatments were carried out using water, 0.1 M HCl, NaOH and FeCl3at 121 °C for 15 min, followed by simultaneous saccharification and fermentation (SSF) as well as separate hydrolysis and fermentation (SHF). The raw and pretreated lignocellulosic feedstocks were analyzed using Fourier transform infrared spectroscopy. Saccharification and fermentation were accomplished using Trichoderma reeseicellulase and Saccharomyces cerevisiae, respectively. The products obtained after saccharification and fermentation were collected and analyzed for reducing sugars and ethanol contents using 3,5-dinitrosalicylic acid and high-performance liquid chromatography, respectively. Enzyme hydrolysis of the FeCl3and HCl treated samples resulted in hydrolysates containing 3.845 and 3.402 mg/ml glucose equivalent, respectively. In all pretreatments, SSF for each pretreatment produced more ethanol than the SHF method; the FeCl3pretreatment gave the highest ethanol yield of 3.011 ± 0.034 and 3.802 ± 0.041% in the SHF and SSF methods, respectively. Utilization of FeCl3pretreatment of rice husk is a potential option for bioethanol production in the future.

Some organic pollutants change the color, smell, and other characteristics of water leaving it undesirable for use. However, other organic pollutants do not change the physical properties of the water, yet, they make the water non-useful. This study was carried out to determine the characteristics of petroleum contaminated water and how it can be purified using economical filters for possible reuse in rural areas of the Niger Delta, of Nigeria. The filters were made from rice husk ash, and white clay, as main materials, while calcium carbonate and poly (propylene carbonate) were used as binders and pore former. The water samples were tested for conductivity, turbidity, pH, heavy metals, and total hydrocarbon contents. The results showed a significant decrease in the amount of petroleum/organic pollutants present in the water sample before purification. The filter candle made using poly (propylene carbonate) as a binder was found to be the most efficient in removing organic pollutants, but it was not very effective in the removal of heavy metals and also, the pH of the filtrate became more acidic. Filtrates from other filters, however, had pH in an acceptable range. Dodecanoic acid and hexadecanoic acid were found to be removed from the polluted water using the filters.