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Hydrodeoxygenation (HDO) is an effective route to upgrade bio-oil to hydrocarbon bio-oil, but the development of efficient catalysts for bio-oil HDO still remains a challenge. In this study, non-sulfided Fe-Co/SiO 2 catalysts were used to upgrade bio-oil using HDO. A series of Fe-Co/SiO 2 catalysts with different Fe/Co mole ratios were prepared, characterized and evaluated. The Fe and/or Co loading did not change SiO 2 crystalline structure. The Fe and/or Co metals increased the amount and strength of Fe-Co/SiO 2 catalyst acidity. Physicochemical properties of upgraded bio-oils produced using Fe-Co/SiO 2 catalysts such as water content, total acid number, viscosity and higher heating values improved in comparison to raw bio-oil. Bimetallic Fe-Co/SiO 2 catalysts resulted in better HDO performance than monometallic Fe/SiO 2 or Co/SiO 2 catalysts. This was due to the synergistic effect of Fe and Co occurring on the SiO 2 support. Fe-Co/SiO 2 catalyst having medium amount of acidity was more effective for bio-oil upgrading. The highest hydrocarbons content produced using Fe-Co(1)/SiO 2 catalyst was 22.44%. The mechanism of bio-oil HDO on Fe-Co/SiO 2 catalysts is proposed. [ABSTRACT FROM AUTHOR]

A series of NiO/HZSM-5 catalysts were used to convert alkali lignin to hydrocarbon biofuels in a two-stage catalytic pyrolysis system. The results indicated that all NiO/HZSM-5 catalysts reduced the content of undesirable phenols, furans, and alcohols of the biofuel compared to non-catalytic treatment. The NiO/HZSM-5 catalyst with the lowest amount of NiO generated the highest biofuel yield in all catalytic treatments, and it also produced biofuel with the highest content of hydrocarbons. The emission of carbon oxides (CO and CO2) increased in the treatments with higher-NiO loading HZSM-5 due to the redox reaction between NiO and the oxygenated compounds in the bio-oil. Ni2SiO4 was generated in the used NiO/HZSM-5 catalysts during the high-temperature pyrolysis process. [ABSTRACT FROM AUTHOR]

Raw bio oil includes multicomponents. In order to avoid the interference between complex reactions, the model compounds, instead of the real bio oil, have been widely used for the study of raw bio-oil upgrade. In this work, the hydrodeoxygenation (HDO) of raw pine pyrolysis bio oil was investigated at 200 °C using Pd/Zn synergistic catalysis under hydrogen pressures of 200, 300, and 400 psi, separately. The resulting product included gas, liquid, and coke. The gas was characterized using a gas chromatography. The liquid was characterized using a gas chromatography-mass spectrometry. The results showed that the HDO performance achieved promotion to some extent by the Pd/Zn synergistic catalysis compared with use of Pd/C or Zn2+, independently. The HDO also gave rise to improvements on physicochemical properties of bio oils. Notably, the highest water content (13.16 wt%) revealed that deoxygenation reaction could be promoted by Pd/Zn synergistic catalysis compared with use of Pd/C or Zn2+, independently. More importantly, the highest hydrocarbon yield (19.15% on the base of liquid part) could be obtained by the treatment of 300 psi pressure and 200 °C temperature over Zn/Pd/C synergistic catalysis. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Although most of jet fuels are currently made from petroleum, nonfood oilseeds such as flax and canola seeds may be an alternative for renewable jet fuel production in the near future. Vegetable oils produced from those oilseeds can be upgraded to liquid hydrocarbons to produce renewable jet fuels. The production efficiency and cost are heavily relied on the vegetable oil fatty acid profile (FAP). Previous research indicated that vegetable oil FAP is affected by oilseed species and oil extraction conditions. Cold press oil extractions from flax and canola seeds were conducted. The effect of the frequency controlling the screw rotating speed on the oil extraction efficiency and quality was discussed. Characterization of the vegetable oils produced, including density, pH value, viscosity, moisture, element component, heating value and FAP, was carried out. The residual oil contents left in the cold press meals were also determined. The results show that the oil extraction efficiency of oilseeds increased when the frequency decreased. For flax and canola seeds, their highest oil extraction efficiency was the same (81.0%), which was both obtained at 15 Hz. The cold press frequency had a minor influence on the FAPs of flax oils. However, the FAPs of canola oils produced at 15 Hz were different from those produced at 20 Hz and 25 Hz to some extent. The main fatty acid in flax and canola oils was linolenic acid and erucic acid, respectively. [ABSTRACT FROM AUTHOR]

A series of Co-Mo/HZSM-5 catalysts was prepared using an impregnation method for the thermal conversion of prairie cordgrass (PCG). The catalysts were characterized by BET measurements, XRD, FTIR spectroscopy, and TEM. The Co-Mo/HZSM-5 catalysts were tested in the thermal conversion of PCG to produce hydrocarbon biofuel in a two-stage catalytic pyrolysis system. The products were analyzed and included incondensable gas, bio-oil, and biochar. Compared to non-catalytically obtained bio-oil, the chemical composition, water content, higher heating value, viscosity, and density of the catalytic bio-oils were improved. The results indicated that 4 %Mo-2 %Co/HZSM-5 showed a robust ability in the catalytic cracking of PCG with the highest yield of hydrocarbons at 41.08 %. [ABSTRACT FROM AUTHOR]

Individually, sunflower oil produced from inedible sunflower seeds with hulls and sunflower meats without hulls were catalytically cracked over the ZSM-5 catalyst in a fixed-bed reactor at three reaction temperatures (450 °C, 500 °C, and 550 °C). Characterizations of hydrocarbon biofuel, distillation residual, and non-condensable gas were carried out. The reaction temperature on the hydrocarbon biofuel yield and quality from sunflower seed oil and sunflower meat oil were discussed and compared. In addition, a preliminary cost analysis of the sunflower seed dehulling was carried out. The results showed that the highest hydrocarbon biofuel yield was obtained from upgrading sunflower meat oil at 500 °C. The highest meat hydrocarbon biofuel yield was 8.5% higher than the highest seed hydrocarbon biofuel yield. The reaction temperature had a significant effect on the distribution of non-condensable gas components. Furthermore, the reaction temperature affected the yield and properties of hydrocarbon biofuel. The unit cost of producing sunflower meat oil was lower than that of producing sunflower seed oil. Comprehensively, sunflower meat could be a more economical feedstock than sunflower seed to produce hydrocarbon biofuel. [ABSTRACT FROM AUTHOR]

In an energy-limited world, biomass may be converted to energy products through pyrolysis. A byproduct of this process is biochar. A better understanding is needed of the sorption characteristics of biochars, which can influence the availability of plant essential nutrients and potential water contaminants such as phosphorus (P) in soil. Knowledge of P retention and release mechanisms when applying carbon-rich amendments such as biochar to soil is needed. The objectives of this study were to quantify the P sorption and availability from biochars produced from the fast pyrolysis of corn stover ( Zea mays L.), Ponderosa pine ( Pinus ponderosa Lawson and C. Lawson) wood residue, and switchgrass ( Panicum virgatum L.). We determined the impact of biochar application to soils with different chemical characteristics on P sorption and availability. Sorption of P by biochars and soil-biochar mixtures was studied by fitting the equilibrium solution and sorbed concentrations of P using Freundlich and Langmuir isotherms. Biochar produced from Ponderosa pine wood residue had very different chemical characteristics than corn stover and switchgrass. Corn stover biochar had the highest P sorption (in average 79% of the initial solution P concentration) followed by switchgrass biochar (in average 76%) and Ponderosa pine wood residue biochar (in average 31%). Ponderosa pine wood residue biochar had higher bicarbonate extractable (available) P (in average 43%) followed by switchgrass biochar (33% of sorbed P) and corn stover biochar (25% of sorbed P). The incorporation of biochars to acidic soil at 40 g/kg (4%) increased the equilibrium solution P concentration (reduced the sorption) and increased available sorbed P. In calcareous soil, application of alkaline biochars (corn stover and switchgrass biochars) significantly increased the sorption of P and decreased the availability of sorbed P. Biochar effects on soil P was aligned with their chemical composition and surface characteristics. [ABSTRACT FROM AUTHOR]

The effect of biochar addition on the chemical properties of acidic soil such as soil pH, electrical conductivity (EC), cation exchange capacity (CEC), and exchangeable acidity were investigated to determine the liming potential of biochars. This study was conducted by incubating acidic soil (clayey, smectitic, acid, mesic, shallow, Aridic Ustorthent) of pH < 4.80 with biochars for 165 days. The biochars were produced from two biomass feedstocks such as corn stover (Zea mays L.) and switchgrass (Panicum virgatum L.) using microwave pyrolysis (at 650°C). Corn stover biochar, switchgrass biochar, and lime (calcium carbonate) were applied at four rates (0, 52, 104, and 156 Mg ha−1) to acidic soil. Amendment type, application rate, and their interaction had significant effects (p < 0.05) on soil pH, EC, and CEC of acidic soil. Exchangeable acidity was significantly affected by amendment type. Application of corn stover biochar had shown a relatively larger increase in soil pH than switchgrass biochar at all application rates. The ameliorating effect of biochars on chemical properties of acidic soil was consistent with their chemical composition. [ABSTRACT FROM AUTHOR]

Design skill is an integral part of an engineer's education. Hence, incorporating a design course into agricultural engineering education in Africa will create agricultural engineers who are not only technically strong, but also innovators. The need for well-planned design input for agricultural engineering students is evident, by looking at the changing scenario in the world of work. It is envisaged that a formal course would serve better than occasional pieces of design-related information cited in individual subjects. A new core course on Design Methodology intended for agricultural engineering students in Africa is proposed and a framework of implementation and evaluation is presented. A design cycle consisting of needs analysis, concept hunt, environmental conditions, function-analysis, ergonomic and aesthetic parameters is described. The course incorporates elements of research, conceptualization and decision making. It is also expected to stimulate thinking, group discussions and creativity in general The course would enable the students to conceive, formulate and take up design-orientated final year projects. The course proposed here may be introduced in agricultural engineering programmes throughout Africa to improve students' education. Whether they pursue careers in industry or academia, this course will prepare agricultural engineers in Africa to be engaged in problem solving from the moment they enter the professional field. [ABSTRACT FROM AUTHOR]

Abstract: The goal of this study was to determine the comparative properties of dry-formed medium density fiberboards (MDF) made from renewable biomass (wheat and soybean straw) and those from conventional soft wood fiber. The MDF properties evaluated were modulus of elasticity, modulus of rupture, internal bond strength, thickness swell, and screw holding capacity. The results show that MDF made from wheat straw fiber and soy straw fiber have weaker mechanical and water resistance properties than those made from softwood fiber. Soybean straw is comparable to wheat straw in terms of both mechanical and water resistance properties to make MDF. Water resistance of MDF decreased drastically with increasing straw fiber composition. Wheat straw fiber and soybean straw fiber should be physically or chemically treated to increase their water resistance property for MDF production. [Copyright &y& Elsevier]

An article is presented describing the background information on the use of ozone, bacteriocins and irradiation for destroying pathogens in food products. Their effectiveness on some pathogens of importance in food processing systems and issues of concern are highlighted. It could be concluded that although each one has the potential for use as an alternative preservation technology in specific food processing applications, no single method, except irradiation, is likely to be effective against all food spoilage and food poisoning microorganisms in all food matrices. However, the synergistic effect of one of these methods and other 'hurdles' or modes of food preservations could be used to ensure the microbial safety and prevention of the development of undesirable sensory and chemical changes in some food products. Bacteriocins may contribute an additional barrier in the 'hurdle concept' of food safety. [ABSTRACT FROM AUTHOR]