Evaluation of Blends of Agricultural Solid Biomass Waste for Solid Fuel Production

In this study, the calorific values of solid fuel samples and their blends in different proportions were determined. Waste samples as sawdust, charcoal, palm kernel bagasse, palm kernel shell, corn cob, palm fronds and coconut shell were subjected to combustion in an isothermal bomb calorimeter and their heating temperature profiles and corresponding heating values were estimated. Individual materials and different blending ratios in weight by weight (1:1, 1:1:1, 3:1:1, 1:3:1, and 1:1:3) heating contents were established. Burning time test was evaluated for blended materials with highest caloric values. Charcoal had the highest calorific value amongst all individual samples with a calorific value of 17,062 kJ/kg with palm fronds having the least heating value of 12,997 kJ/kg. In the 1:1 ratio mix, charcoal:palm oil bagasse had the highest heating content of 21,907 kJ/kg. Considering the ratios of three different solid mass in varying weight proportions, the combination of charcoal:coconut shell:palm oil bagasse (1:1:1) in equal weight percent gave the highest heating content of 23,373 kJ/kg. The blend of charcoal:coconut shell:palm kernel bagasse had the highest burning time of 20 minutes and 12 seconds. From the evaluations, charcoal in mixed proportions with other solid biomass are excellent materials to be considered for solid fuels production

Oxidation Stability of Fatty Acid Methyl Ester under Three Different Conditions

Maintaining fuel stability is one important criterion in sustaining the quality of fuels. This research investigated the production of biodiesel from waste groundnut oil and the oxidation stability of the biodiesel samples stored under three conditions (a vacuum, a fridge and an exposure to atmosphere) by considering their saponification values, percentage of free fatty acid, peroxide values, iodine values and viscosity. Maximum biodiesel yield was obtained at 9 methanol/oil mole ratio, 1.0w/w%Oil KOH catalyst concentration, reaction time of 60 minutes and reaction temperature of 60 0C. The results showed that biodiesel oxidation stability is adversely affected by increase in saponification value, percentage of free fatty acid, peroxide value; and decrease in iodine value and viscosity. Also, the results of these physico-chemical properties shows that vacuum is the most favourable storage condition, compared to freezing and atmospheric conditions. Keywords: Atmosphere, Biodiesel, Refrigerator, Trans-esterification, Vacuu

ASSESSMENT OF THE POTENTIAL EMISSIONSFROM BIODIESEL PRODUCED FROM GROUNDNUT AND SOYBEAN OILS

Biodiesel an alternative fuel to fossil fuel) does not only require production at commercial level, but the production process also needs to be a clean and environmental friendly. This research aim at assessing the potential emissions form the biodiesel produced from the trans-esterification of groundnut oil and soybean oil, using KOH homogenous catalyst. The impact assessment of the potential emissions wasanalysed, quantified and characterized using Simapro 8.2.3.0. Comparatively, soybean biodiesel produced higher yield of biodiesel compare to yield obtained from groundnut oil biodiesel, under same experimental conditions. Also, high yields of biodiesel observed (97.1 % using both soybean oil and 92.1 % using groundnut oil) were at experimental conditions of 52.5oC and catalyst concentration 0.9 wt/wt%, at constant methanol/oil mole ratio of 6 and reaction time of 1 hour. The impact assessment of the emissions from the biodiesels obtained from the two oils revealed that groundnut oil biodiesel has the potential to release more fresh water toxic substances, terrestrial toxic substances and human toxic substances

Estimation of critical fluxes, thermal stabilities and failure criteria of cellulose‐based membranes and modelling of salt diffusivity during pervaporative desalination

The consequences of highly saline freshwater on the ecosystem and humans are quite alarming and have gained little attention in recent times. Progressive advances in pervaporation have helped to unlock its potentials in the desalination of salty streams. In this study, desalination of lagoon‐water using cellulose acetate membrane (CAM) and its copper‐doped nanocomposite (CA‐CuNP) membrane was investigated. A newly developed model was used in estimating salt diffusion coefficients in steady and unsteady state situations. At the experimental phase, permeate fluxes increased with temperature but dropped when the critical fluxes (5.11–6.01 L/m2h and 5.29–7.56 L/m2h) were exceeded for the CAM and CA‐CuNP membranes respectively. At steady state, the critical permeate volumes for the pristine and nanocomposite membranes were 0.2273 and 0.1826 L with corresponding fluxes of 0.034 and 0.031 L/m2h after 10 and 9 h, respectively. The estimated steady and unsteady diffusivities for the membranes are: 1.46 * 10–4–8.43 * 10–3 m2/h (4.06 * 10–7–2.34 * 10–6 m2/s) and 2.44 * 10–4–0.17 * 10– 4 (6.78 * 10–8–4.72 * 10–9 m2/s), respectively. The nanocomposite membrane gave slightly higher salt rejection with fluxes mimicking the power law model. Thermal resistance of the pristine membrane improved from 219.36 to 221.18 °C after doping it with copper nanoparticles. Furthermore, the estimated critical permeate fluxes are indicative of saturation conditions for the CAM and CA‐CuMP membranes and hence are signals for membrane plugging which then implies that proactive measures can then be taken to abate such situations

Synthesis of PET-Magnesium Oxide-Chitosan Nanocomposite Membranes for the Dehydration of Natural Gas

Flat thin-film magnesium oxide-chitosan nanocomposite membranes were synthesized with polyethylene terephthalate (PET) and employed for natural gas dehydration. The water vapor permeation was most pronounced with a nanocomposite membrane doped with 0.9 g MgO nanoparticles (NP) as a result of a significant upsurge in the permeability of water vapor in the membrane (0.87). With the increase in MgO NP, large macro-voids are created, substratum pore size, and thickness together with the water vapor permeation were upsurged. The dehydration of natural gas performance of magnesium oxide-chitosan nanocomposite membranes synthesized with PET was enhanced with the increase in MgO NP embedded in the membrane. Though water vapor permeation was restricted by the polyester non-woven material used as a support for the nano composite membranes, as the three membranes did not reach the permeation coefficient of 1. However, the permeation coefficient increased with an increased MgO NP, with three mambrane samples (M1, M2 and M3) having permeation coefficient of 0.763, 0.77 and 0.87 respectively. The gas reduced with an increase MgO NP, with M1, M2 and M3 having 3.46×10−2, 3.17×10−2 and 3.88×10−3 kg/m3 respectively. From the adsorption study, the discrepancy observed between CH4 and vapor with isotherm models was ascribed to the different adsorption behavior of CH4 and vapor on the membrane-active area. The cost of making the membrane cannot be considered as a terminal criterion because most of the cost-effective option is not always the optimum one. The membranes confirmed their suitability for the dehydration of natural gas

A comparative evaluation of fermentable sugars production from oxidative, alkaline, alkaline peroxide oxidation, dilute acid, and molten hydrate salt pretreatments of corn cob biomass

Production of high value-added products from lignocelluloses is an economically sustainable alternative to decreasing dependence on fossil fuels and making the chemical processes environmentally friendly. In this study, different methodologies of alkaline (Ca(OH)2 and NaOH), dilute acid (10%w/w H2SO4), hydrogen peroxide (H2O2), alkaline peroxide oxidation (H2O2/Ca(OH)2 and H2O2/NaOH), and molten hydrated salt (MHS) mediated (ZnCl2.4H2O) pretreatments were employed in the hydrolysis of corncob amenable to enzymatic hydrolysis. Optimal enzyme hydrolysis temperature (considering 45 and 50 ℃) and time (2, 24, 72, and 96 h) were investigated for each pretreatment procedure to ascertain the concentrations of glucose, xylose, and total sugar present in the corncob. At 45 ℃ and 96 h, NaOH alkaline pretreatment achieved the best optimum total sugar production of 75.54 mg/mL (about 54% and 88% increments compared to dilute acid pretreatment (35.06 mg/mL total sugars) and MHS (9.32 mg/mL total sugar) pretreatment respectively). In this study, total sugars production increased appreciably at 45 ℃ and longer hydrolysis period (96 h) compared to hydrolysis at 50 ℃ (with maximum total sugars production of 18.00 mg/mL at 96 h). Scanning electron microscopic imaging of the untreated and treated samples displayed cell wall distortion and surface disruptions.Covenant University, Ota, Nigeria.http://www.aimspress.com/journal/energypm2021Chemical Engineerin

A Review on Corrosion in Concrete Structure: Inhibiting Admixtures and Their Compatibility in Concrete

The development in marine industry and its effort in building bridges has placed a huge demand on reliability and duration of service of reinforcing steel in concrete. Literature has documented several studies on corrosion of reinforcing steel in concrete induced via carbonation and chloride in marine milieus. Extension of concrete structures service life has been one of the foremost strong worries of the concrete industry, especially for marine industry. Hence, the necessity to employ a cost effect system for shielding the reinforced steel in concrete from corrosion. Studies have shown that one prospective solution in combating corrosion deterioration in reinforced steel in concrete structures is the introduction of corrosion-inhibiting admixtures into concrete. This review discussed at length corrosion in reinforced concrete and corrosion inhibitors in relation to concrete together with the classification of inhibitors based on the method of applications. This review further reports corrosion-inhibiting admixtures in concrete. As a result, the aspects of corrosion inhibitors this manuscript reviewed are corrosion inhibitors employed as admixtures in concrete for new construction in the marine industry. Furthermore, corrosion inhibitors are employed for repairs and maintenances admixed with concrete for patches on marine structures, squirted onto the surface of the concrete or put on the concrete surface via saturation treatment. As a result of the excellent properties of functional nanostructured materials, the advancement in the implementation of functional materials in inhibiting admixtures in concrete is fast growing in marine industry. Hence, the Integration of functional materials in inhibiting admixture and their compatibility were reviewed. The significance of inhibitors employed as admixtures in concrete for practical applications of corrosion are the suppression or mitigation of corrosion process of metals used in marine industry and the patches of already constructed structures. The current problems related to corrosion-inhibiting admixtures in concrete and the future research and development directions were discussed

Synthesis and characterization of zeolite-Y using Ficus exasperata leaf: A preliminary study

In this study, Ficus exasperata (Fe) leaf (sand paper leaf) raw sample was characterized using proximate and ultimate analysis and the ash was characterized using X-ray fluorescence (XRF), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) spectroscopy. XRF analysis showed that Alumina (Al2 O3) and Silica (SiO2) were 6.50% and 67.50%, Energy Dispersive X-ray (EDX) analysis showed high presence of silica (42.40%), alumina (15.00%) and Oxygen (20.80%). FTIR unveiled peaks with zeolite-Y patterns. SEM analysis indicates good surface morphology and hexagonal shaped crystal lattice in comparison with commercial zeolite-Y

Data on calcium oxide and cow bone catalysts used for soybean biodiesel production

Biodiesel was produced from soybean oil using calcium oxide and cow bone as heterogeneous catalysts, through transesterification process. The soybean oil used was characterized using gas chromatography mass spectrometer (GCMS) and the cow bone catalyst produced was characterized X-ray fluorescence (XRF) spectrometer. The effects of the variation of methanol/oil mole ratio, catalyst concentration and reaction temperature on biodiesel yield during the transesterification of soybean oil were investigated. Reaction time of 3 h and stirring rate of 500 rpm were kept constant. Using Response Optimizer (Minitab 17), the optimum conditions for biodiesel production were established. It was observed that the calcination of cow bone catalyst enhanced its conversion to apatite-CaOH. Also, the results obtained showed that the performance trends of calcined cow bone catalyst and the conventional CaO catalyst were similar. Keywords: Biodiesel, Calcined cow bone, Catalyst, Soybea