Determination of Uptake and Release of 2,4-Dichlorophenol on the Nigerian Clay Soil using Gas-Liquid Chromatography

The uptake and release of 2,4-dichlorophenol on Nigerian clay soil was studied by introducing varying concentrations of the chlorophenol in 0.01 M aqueous calcium chloride solution at pH 4.5 into pretreated clay (0.6% OM) samples. The clay soil was treated with hydrogen peroxide followed by varying  concentrations of sulphuric acid (0.1, 2.0, 4.0 and 6.0 N). The uptake of 2,4-dichlorophenol was higher for treated clay soil samples with lower cation exchange capacity. The sorption isotherm plots were  non-linear, suggesting that sorption of sorbate onto sorbent is by adsorption mechanism and that charged species are involved. The sorption process was well described by the Freundlich isotherm. Clay soil samples with higher cation exchange capacities released smaller amounts of the adsorbed chlorophenols, therefore retaining close to half of the adsorbed amount due to strong adsorption of the charged species on the clay surface. The clay soils with lower cation exchange capacities released higher amounts of the adsorbed chlorophenols, due to the higher contribution of hydrophobic interaction between organic matter and hydrophobic sites on the clay surface.KEYWORDS: 2,4-dichlorophenol, adsorption, sulphuric acid treatment, hydrophobic interaction, desorption

Alternative Energy Source in a Developing Country: Biodiesel Option in Nigeria

The depleting reserves of petroleum and attendant environmental issues have led to the search for more eco - friendly and renewable fuels. Biodiesel obtained from various renewable sources have been  recognized as one of the alternative fuels due to its biodegradability, high cetane number, no sulphur emissions and low  volatility. In this paper, biodiesel was obtained from waste frying oil (WFO) by esterification to reduce the free fatty acid (FFA) content (determined by standard titration methods) and then transesterified using base catalyzed transesterification method. The WFO had an FFA content of 11.3%. The WFO was esterified hourly (1, 2, 3, 4) for reduction in %FFA until about < 1% FFA was achieved prior to transesterification. The esterified oil was transesterified in batches to establish  optimum conditions for the reaction by varying; time, temperature, stirring speed and methanol to oil molar ratio respectively. The methyl ester yield from the efficient based catalyzed transesterification of WFO were found to be 50oC, 6:1 methanol-to-oil molar ratio, 1% w/v catalyst concentration and a reaction time duration of 40 minutes, 96% optimum yield and the result of the FTIR analysis confirms the formation of methyl ester having wavelength of absorption at  2959.475nm, 2784.153nm, 1747.191 and 1469.005 respectively. The fuel properties of the methyl ester produced were compared with set ASTM standards and were found to be in line with the standards.Keywords: Waste frying oil, co-solvent, Transesterification, Yield, FTIR analysis and Fuel Propertie

Phytochemical and Antioxidant Properties of Pericap of Garcinia kola Extract

The powdered pericap of the plant was extracted with methanol at room temperature of 25OC, partitioned with n-hexane, ethylacetate and butanol respectively. The extract and fractions were subjected to phytochemical analysis using established standard procedures. Antioxidant screening using DPPH (2, 2−diphenyl−1−picryl hydroxyl radical) procedure was carried out on the fractions and compared with ascorbic acid as standard. The result of the screening revealed that the pericalp contained alkaloids, flavonoids, tannins and saponins as chemical constituents. The (DPPH) radical scavenging assay of the plant revealed high antioxidant activity.There was significant activity among the extract and fractions, with the petroleum ether fraction showing the highest activity. The study demonstrated that the pericap of the plant is a good source of antioxidants. Keywords: Antioxidants, phytochemical, extracts, pulp, Garcinia kol

Phytochemical and Anticancer Studies on Ten Medicinal Plants Used in Nigeria

Ten medicinal plants used in Nigerian ethno medicine were subjected to phytochemical and anticancer studies using established standard procedures. The result of the study revealed the presence of phytochemical constituents such as alkaloids, saponins, tannins and flavonoids. Anona muricata, Andrographis paniculata and Garcinia kola were active against the lung cancer cell lines at different concentrations. The study justifies the use of the plant in traditional medicine as remedy against cancer. Keywords: cytotoxic, anticancer, plant extract