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The discharge of oil and grease (O&G) containing effluent without treatment may contaminate the aquatic environs and freshwater. The removal of O&G from simulated refinery desalter effluent (SRDE) by activated carbon (AC) originated from chemical activation/carbonization of corn cobs (CCs) was investigated through fixed-bed column studies. The corn cobs activated carbon (CCAC) was characterized to determine its physicochemical properties, and the functional groups presently active on it partaking in the column adsorption process. The CCAC size (150, 300 and 600 µm), initial adsorbate concentration (200, 300 and 400 mg/L), and bed height (100, 200 and 300 mm) were varied to observe their influence on the adsorption of O&G and breakthrough time (τ) at a constant flow rate of 10.5 mL/min in a 10 mm diameter column of length: 60 mm. The removal of O&G from SRDE was inspected using the Bohart-Adams (B-A) and Yoon-and-Nelson (Y-N) kinetic models. Breakthrough time and %O&G removal decreased with increasing CCAC particle size and feed concentration and improved with rising bed height (BH). The void fractions (ε) at BHs of 100, 200 and 300 mm were 0.0247, 0.0124 and 0.0082, respectively. The ideal residence time () was 4.49 min. The B-A model yielded the highest degree of fit to the data than the Y-N model with R 2 within 0.8217 and 0.9771. This means that the B-A model can be used to predict the breakthrough curve of any desired values for the present study. This work also revealed that CCs could be packed in a fixed-bed column for O&G reduction from refinery desalter effluent.

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Temperature relationships of Vigna subteranea flower (VSFE) extract on the corrosion of carbon steel in 2.0 M H2SO4 at 303-323 ˚K was studied by weight loss method. The obtained results show that VSFE extract acts as inhibitor for carbon steel in H2SO4 solution. The inhibition efficiency was found to increase with increase in VSFE extract concentration but decreased with acid concentration and temperature, which is suggestive of physical adsorption mechanism although chemisorption may play a part. The adsorption of VSFE onto the carbon steel surface was found to follow the Langmuir adsorption isotherm. The correlation coefficient (R²) ranging from 0.9992 ≥ R² ≤ 0.9715 was obtained. Both kinetic parameters (activation energy, pre-exponential factor, enthalpy of activation and entropy of activation) and thermodynamics of adsorption (enthalpy of adsorption, entropy of adsorption and Gibbs free energy) were evaluated and discussed from the effect of temperature on the corrosion and inhibition processes.

Abstract:In this research work, melon oil was used as feedstock for methyl ester production. The research was aimed at optimizing the reaction conditions for methyl ester yield from the oil. Response surface methodology (RSM), based on a ve level, four variable central composite designs (CCD) was used to optimize and statistically analyze the interaction e ect of the process parameter during the biodiesel production processes. A total of 30 experiments were conducted to study the e ect of methanol to oil molar ratio, catalyst weight, temperature and reaction time. The optimal yield of biodiesel from melon oil was found to be 94.9% under the following reaction conditions: catalyst weight -0.8%, methanol to oil molar ratio -6:1, temperature -55• C and reaction time of 60mins.The quality of methyl ester produced at these conditions was within the American Society for Testing and Materials (ASTM D6751) speci cation.