Kinetic Studies of Catalytic Oxidation of Cyclohexene Using Chromium VI Oxide in Acetic Acid Medium

Cyclohexene was oxidized using chromium (VI) oxide (CrO3) in pure acetic acid medium. The products of oxidation were analysed using simple qualitative analysis, IR spectroscopy and Gas chromatography-Mass spectrometry (GC/MS). Kinetics studies were carried out to determine the order of reaction, rate constant and the activation energy with respect to the oxidant using pseudo-order approximation method. The influence of Cu2+, Co2+ and Fe2+ as catalysts were also investigated. Qualitative analyses of the products revealed the presence alcohols and ketones while the GC/MS shows the presence of cyclohexanol (2.46%), cyclohexanone (5.05%), 2-cyclohexen-1-one (59.37%), 1,2-cyclohexanediol monoacetate (9.88%), 2-hydroxy-cyclohexanone (1.75%) and bi-2-cyclohexen-1-yl (5.16%). The reaction order was shown to be 2nd order with respect to the CrO3 with activation energy of 45.32 kJ mol-1 while Co2+ and Fe2+ indicated some catalytic activity on the reaction

Mechanism for partial oxidation of Cyclohexene by Chromium (VI) oxide in acetic acid

The oxidation of cyclohexene by chromium (VI) oxide in aqueous and acetic media has been studied. The reaction products were analysed using classical method, IR and GC/MS analyses. The major products of the oxidation reaction in acetic acid medium are cyclohexanol, cyclohexanone, cyclohex-2-en-1-one, cyclohexan-1,2-diol monoacetate and  Bi-2-cyclohexen-1-yl. However, no reaction was observed between cyclohexene and chromium (VI) oxide in aqueous medium. Based on the result a mechanism for the oxidation reactions has been proposed involving dissociation of acetic acid to form an acetate anion which attacks the chromium (VI) oxide to form an acetochromate ion. The latter then attacks cyclohexene to form an acetochromate cyclohexenyl ion intermediate which undergoes electron shift and rearrangement to produce cyclohexanone and chromium (IV) oxide, thereby regenerating the acid. The proposed mechanism suggests that the acetic acid serves both as homogeneous catalyst as well as medium for the reaction

Assessment of Physicochemical Properties of Biodiesel from African Grapes (Lannea microcarpa Engl.& K.Krause)

The African Grape (Lannea microcarpa) seed oil was extracted and subjected to fuel properties tests according to standard method for oil and fuel analysis to evaluate its suitability as oil crop for biodiesel production in Nigeria. The oil was transesterified using alkali hydrolysis to biodiesel. The yields of the oil and its methyl ester were 41.20 ±1.32% and 85 ± 1.30% respectively. The biodiesel produced was analysed for its  physicochemical properties and yielded the following properties; kinematic viscosity at 40oC (5.80 cSt), acid value (1.66 mgKOHg-1), flash point (96 oC), cloud point (+9oC), sulphur content (0.03 wt %), and free glycerol (0.54%). The results obtained showed that most of the important properties were within the recommended standards for a biofuel grade biodiesel and suggest the potential of L. microcarpa seeds as a source of biodiesel.Keywords: African Grape, Lannea microcarpa, Seeds, Oil, Biodiese

The Effect of Trichlia emetica Leaf Extract on the Flammability of Flexible Polyurethane Foam

Due to the health and environmental consequences of conventional flame retardants the incorporation of new plant based flame retardants becomes imperative. Hence the choice of the leaves of Trichlia emetica as a flame retardant on flexible polyurethane foam based on Hausa folklore tradition that it is used as a flame retardant. Analysis of the treated flexible polyurethane foam revealed that add on percentage ranged from 9-21%, Ignition time between ranged within 6-14 sec, flame propagation rate 0.42-0.22 cm/s, after glow time decreased from 12 sec to 2 sec and char formation increased from 18% to 26%. Which indicated a modification of the flammability characteristics of the flexible polyurethane foamKeywords: Add on, After glow, Char, Flame propagation rate, Flame retardants, Ignition time, Polyurethan

Study of Bioavailability of Ca and Zn in the Flesh of Yellow Terminalia catappa (Linn) Fruits

The analyses of antinutritional and mineral composition of the flesh of yellow fruits variety of Terminal catappa using standard methods were conducted. The results (mg/100g dry sample) are as follows: Total oxalate 1.90, soluble oxalate 1.62, tannin 16.28, phytate 2872.67, saponin 1.495, nitrate 0.64, hydrocyanic acid 4.19, Ca 143.30, Mg 48.50 and Zn 1.42. Bioavailability studies revealed that the oxalate content of the fruit have no effect on Ca availability as Oxalate]/[Ca] and [Oxalate]/[Ca + Mg] are below critical level of 2.5. However, phytate affect both the Ca and Zn bioavailability with [Phytate]/[Ca] and [Ca][Phytate]/[Zn] above critical level of 0.2 and 0.5 respectively.Keywords: Anti-nutritional, Terminal catappa, fruits, minerals, bioavailability

Comparative Studies of Gasoline Samples Used in Nigeria

Comparative analysis was carried out on five samples of gasoline in the Nigerian market based on octane number, sulphur content, Reid vapour pressure, specific gravity, boiling point characteristics and chemical content. The result revealed that, Nigerian and Kuwait gasolines have low octane numbers in comparison to others. The Nigerian sample has the least sulphur content while the Holland has the highest. The specific gravities were all within the acceptable range of 0.75-0.85. Likewise the boiling point characteristics of all the samples were within suitable values in favour of Nigerian weather conditions. Chemical composition analysis shows high proportion of aromatics, above acceptable limits and low oxygenated compounds. The findings revealed that the quality of some gasolines being sold in Nigeria is below the international standard

Contribution of Factors Affecting Crop Production in Bangladesh: An Empirical Analysis with Production Function Approach

Bangladesh has achieved a tremendous success in food production in last few decades amidst challenges of land degradation, land use changes and climate effect. In spite of the increasing trend of yields of crops, there still remain some challenges to meet the growing needs due to increase in population and loss of land to development activities. This study aims to identify the rate of contributions or economics of factors of crop production in Bangladesh. Cobb-Douglas production function has been applied in this study of crop production using a number of production factors within the broad terms land, labour and capital. Secondary data, representing factors of production, have been selected based on literature reviews so that they can be appropriate for this study. Data of crop production have been considered as dependent variables, whereas, land area coverage for agricultural production, labour employed in agriculture, agricultural household expenditure, fertilizer applied and irrigation coverage have been considered as independent variables. Land and labour is negatively correlated with crop production, whereas, fertilizer is positively correlated. Crop production which shows decreasing return to scale deserves the adoption of new technology and good agricultural management practices

Characterization of Dabagi clay deposit for its creamics potential

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