The Swietenia macrophylla wood used for the study was sun dried for about 48 h, pulverized using a hammer mill and then sieved to a particle size of about 425μm using Wiley milling machine. The prepared materials were pyrolyzed in a fixed-bed pyrolysis reactor in the temperature range from 425 to 500 °C. The product yields were collected at an interval of 25 °C. The maximum yield of bio-oil was recorded as 69.5wt.% at the pyrolysis temperature of 450 °C. The physicochemical properties and compositions of the feed materials and produced bio-oil were measured in order to quantify their potential for bio-energy use and industrial applications. The properties specifically measured include density, moisture content, ash content, pH, refractive index, cetane index, elemental composition, viscosity, and heating values. The ultimate analysis of the product showed that the contents of carbon, oxygen, hydrogen, nitrogen, and sulfur were 50.2%, 42.6%, 6.6%, <0.4% and <0.06% respectively. The viscosity, density, pH, moisture content, API gravity, ash content, HHV and LHV of bio-oil produced were found to be 4.6 mm 2 /s, 0.951 g/ml, 5.64, 21.4wt.%, 19.29, 0.15wt%, 29.52 MJ/kg and 28.08 MJ/kg respectively. These values were found to be in the ranges of values reported in the literature for bio-oils produced from biomass. The produced bio-oil had the much needed organic compounds typical of other woody biomass employed in commercial bio-oil manufacture. These compounds were classified into several groups; organic acids, ketones, phenols, alcohols, and aldehydes. The main components identified in the bio-oil are the aromatic and aliphatic compounds as well as carboxyl groups. The GCMS analysis of the product indicated the presence of 24 compounds which are useful as industrial chemicals and flammable gases: they include alkanes, alkenes, phenols, hydrogen, and levoglucosan. This study on bio-oil has demonstrated that mahogany wood is a useful biomass for the much sort potential fossil fuel substitute and finds vast application in the biofuel industry.

The inhibition of carbon steel corrosion induced in 1 M H 2 SO 4 by soy polymer (SP) from an extract of Glycine Mac-L and polyvinylpyrrolidone (PVP) respectively was investigated at 30-60 °C using hydrogen gas evolution, potentiodynamic polarization and quantum chemical computation technique respectively. Results obtained from hydrogen gas evolution technique revealed that SP and PVP respectively acted as an inhibitor for corrosion of carbon steel in 1 M H 2 SO 4 solution. The increase in inhibition efficiency (IE%) of SP and PVP reached a maximum at 89.5% and 84.36% respectively, and the increment was found to be dependent on inhibitor concentration. The combination of mixture of SP and PVP as single inhibitor showed better inhibition improvement compared to individual inhibitor. Temperature study reveals that inhibition efficiency decreased with a rise in temperature suggesting physical adsorption. The computed parameters for the activation energies and heat of adsorption of the corrosion process supported the physical adsorption mechanism proposed. Regression analysis (adsorption isotherm model) was used to approximate the adsorption characteristics of the SP and PVP. Polarization data revealed that SP and PVP respectively adsorption acted as a mixed type inhibitor and also affected the anodic and cathodic partial reactions process. Quantum chemical computations were performed using the density functional theory to establish a clear link existing between the effectiveness of the inhibitor and its electronic properties.

No abstract

No abstract

Animal feeds contributes to a greater percentage of the cost of production of livestock. For the increment in productivity and profit, farmers are advised to produce their feed themselves to reduce the cost of production. This work is aimed at producing a simple single unit fish feed pelletizer at a lost cost for peasant farmers. A fish feed pelletizer has been designed and constructed. It consists of hopper, screw conveyor, barrel, dies, drives system and heater. The design was carried out using engineering principles with due consideration to cost, ease of operation, serviceability, durability, and performance. It is designed to be driven by a 1.5 HP, three-phase electric motor with a heating element of 1500 W attached to the barrel surface to ensure adequate heating of the feed as they travel through the barrel. The test that determines the performance of the pelletizer was carried out which showed a throughput capacity of 17 kg/h, machine efficiency of 73.33% and a pelletizing efficiency of 90.90% with low mechanical damage of 9.10%. The cylindrical pellets size produced by the pelletizer was in the range of 2–8 mm diameter, which is suitable for fish and poultry farming. The machine was produced using locally sourced materials at a production cost of one hundred and eight thousand naira only (N 108,000.00).