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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]

Catalytic fast pyrolysis (CFP): The cover image demonstrates one promising technology (CFP) for converting biomass to liquid biofuels. The yield and quality of biofuels are depended on biomass species, reactor type, operating conditions (temperature, heating rate, etc.) and the activity of appropriate catalysts. Based on current catalytic research, a novel two‐stage reactor was tested for exploration of catalytic biomass pyrolysis. Lignocellulosic biomass materials such as prairie cordgrass can be converted into hydrocarbon biofuel over bifunctional Co‐Mo/HZSM‐5 catalysts, for which the effects of different metal loading levels were investigated for their influence on the pyrolysis products (bio‐oil, bio‐char, and non‐condensable gas). The physicochemical properties (such as water content, density, viscosity, higher heating value, and chemical composition) of pyrolysis products were characterized. The results indicate that integrating two‐stage catalytic pyrolysis system and Co‐Mo/HZSM‐5 could improve the yields and quality of bio‐oil with higher hydrocarbon content. Although further research is needed, the study confirms that catalytic biomass pyrolysis using a two‐stage reactor system might be an effective pathway for converting lignocellulosic biomass to advanced biofuels. More details can be found in the Full Paper by Shouyun Cheng, Lin Wei, Xianhui Zhao et al. on page 706 in Issue 6, 2016 (DOI: 10.1002/ente.201500452). [ABSTRACT FROM AUTHOR]

Although hydrodeoxygenation (HDO) is proven a promising process for upgrading pyrolysis bio-oil to hydrocarbon biofuel, catalyst efficiency remains a challenge. Integrating heterogeneous catalysts with supercritical liquid in a bio-oil HDO process was investigated in this study. Bifunctional Fe-Ni/HZSM-5 catalysts were firstly used to upgrade bio-oil to hydrocarbon biofuel in supercritical methanol. The loading of Fe and Ni did not change HZSM-5 crystalline structure, but BET surface area and total pore volume of Fe-Ni/HZSM-5 catalysts decreased significantly compared to HZSM-5 support. Physicochemical properties of biofuel produced by Fe and/or Ni loaded HZSM-5 catalysts such as water content, total acid number, viscosity and higher heating value improved in comparison with raw bio-oil. Bimetallic Fe-Ni/HZSM-5 catalysts were more effective for bio-oil HDO compared to monometallic Fe/HZSM-5 or Ni/HZSM-5 catalyst , and this was attributed to the synergistic effect of Fe and Ni on HZSM-5 support. Fe-Ni(2)/HZSM-5 catalyst produced biofuel with the highest hydrocarbon content at 28.60%. [ABSTRACT FROM AUTHOR]

Upgraded bio-oil can partly replace fossil fuels to reduce the environmental issues caused by the massive consumption of fossil fuels. Hydrodeoxygenation is a promising route for upgraded bio-oil production from pyrolysis bio-oil. Non-sulfide catalysts are effective in bio-oil hydrodeoxygenation due to low cost and high activity. Ni-Zn/Al 2 O 3 catalysts were first used to selectively produce hydrocarbon upgraded bio-oil through bio-oil hydrodeoxygenation. Upgrading pine sawdust bio-oil to upgraded hydrocarbon bio-oil was performed using a series of Ni and/or Zn loaded Al 2 O 3 catalysts. The crystalline structure of Al 2 O 3 was maintained after Ni and/or Zn loading, but BET surface area and total pore volume of Ni-Zn/Al 2 O 3 catalysts decreased significantly compared to Al 2 O 3 support. Bimetallic Ni-Zn/Al 2 O 3 catalysts were more effective than monometallic Ni/Al 2 O 3 or Zn/Al 2 O 3 catalyst . Bimetallic 15%Ni-5%Zn/Al 2 O 3 catalyst generated the highest upgraded bio-oil yield at 44.64 wt% and produced the upgraded bio-oil with the highest hydrocarbon content at 50.12%. Physicochemical properties of upgraded bio-oils including heating value, water content and pH were significantly improved in comparison with raw bio-oil. The improved catalytic performance of bimetallic Ni-Zn/Al 2 O 3 catalyst was associated with the synergistic effect of Ni and Zn on Al 2 O 3 support. [ABSTRACT FROM AUTHOR]

This study investigated microwave pyrolysis of switchgrass with particle sizes from 0.5 mm to 4 mm and determined the effects of reaction temperature and time on the yields of bio-oil, syngas, and bio-char. A prediction model was satisfactorily developed to describe the bio-oil conversion yield as a function of reaction temperature and time. Second-order reaction kinetics was also developed to model the switchgrass pyrolysis. Switchgrass with different particle sizes was found to be similarly pyrolyzed by microwave heating. The research results indicated that thermochemical conversion reactions can take place rapidly in large-sized switchgrass by using microwave pyrolysis. GC-MS analysis indicates that the bio-oil contained a series of important and useful chemical compounds: phenols, aliphatic hydrocarbons, aromatic hydrocarbons, and furan derivatives. These chemical compounds evolved were related to the pyrolysis conditions. [ABSTRACT FROM AUTHOR]

In this study, modified clean fractionation process was optimized for prairie cordgrass, with usage of alternative organic constituent - ethyl acetate. Other constituents of the solvent mixture included ethanol and water. Clean fractionation solvent was used in different proportions of the constituents. Process efficiency was determined by lignin recovery, solvent composition, as well as time and temperature applied to each sequential process. Glucose yield during enzymatic hydrolysis and overall pretreatment were calculated. Optimal conditions (125°C, 37 min, with the solvent composition of ester:ethanol:water = 32.5:22.5:45) yielded a 20% lignin recovery, 38% glucose yield during enzymatic hydrolysis and 26% xylose recovery in aqueous fraction. [ABSTRACT FROM AUTHOR]

Catalytic cracking of camelina oil over Zn/ZSM-5 catalyst in a fixed-bed tubular reactor was investigated. An optimization study on the catalytic cracking conditions based on nine well-planned orthogonal experiments was carried out. Three main operation conditions including reaction temperature, liquid hourly space velocity and oil extraction press frequency were studied to examine their effects on the yield and quality of hydrocarbon biofuel produced. Characterization of the catalyst, hydrocarbon biofuel and non-condensable gas was conducted. There was no significant difference between the bulk structures of fresh Zn/ZSM-5 and used Zn/ZSM-5. Small ZnO particles dispersed well on the parent ZSM-5. Hydrocarbon biofuel contained 65.18% hydrocarbons and its properties including dynamic viscosity, density and higher heating value were improved after upgrading, compared to camelina oil. It was found that the oil extraction press frequency was the most important factor and liquid hourly space velocity was the least important factor for the hydrocarbon biofuel production. In addition, the optimum conditions for camelina oil upgrading were a combination of reaction temperature of 550 °C, a liquid hourly space velocity of 1.0 h −1 and an oil extraction press frequency of 15 Hz. [ABSTRACT FROM AUTHOR]

Cracking of camelina oil over non-catalyst and ZSM-5 catalyst doped with different Zn concentrations (0, 10, 20 and 30 wt.%) in a fixed-bed reactor was investigated. The fresh and used catalysts were characterized using XRD, FT-IR, BET and TEM. Characterizations of the produced hydrocarbon biofuel, distillation residual and non-condensable gas were carried out. The effect of non-catalyst and catalyst on the physicochemical properties and yield of products was discussed. The results showed that the introduction of Zn did not change the zeolite crystalline structure and ZnO might deposit on the external surface and/or inside the pores of the support ZSM-5. After upgrading, hydrocarbon biofuel had a lower viscosity, lower density, higher heating value (HHV) and higher water content than raw camelina oil. The optimum Zn concentration to ZSM-5 was 20 wt.%, at which the highest hydrocarbon biofuel yield and comprehensively the best quality were obtained. Compared to non-catalytic cracking of camelina oil, the loading of Zn to ZSM-5 could improve some physicochemical properties of the hydrocarbon biofuel. In addition, the loading of Zn to ZSM-5 could facilitate the chemical reactions such as decarbonylation and dehydrogenation. [ABSTRACT FROM AUTHOR]

Abstract: The main objective of this study was to fractionate prairie cordgrass (PCG) obtaining the highest cellulose digestibility. Following clean fractionation (CF) processing, the PCG lignocellulosic biomass was fractionated into three main building blocks: cellulose, hemicellulose and lignin. Effects of processing factors such as time, temperature, catalyst concentration and organic solvent mixture composition were evaluated. Organic solvent–aqueous mixture contained methyl isobutyl ketone (MIBK), ethanol and water in different proportions. Sulfuric acid was used as a catalyst. In order to evaluate the degree of pre-treatment, enzymatic saccharification was employed on the cellulose fraction obtained from the CF process. Response surface methodology was used for process optimization and statistical analysis. Optimal conditions (39min, 154°C, 0.69% catalyst and 9% MIBK) resulted in 84% glucose yield and 87% acid insoluble lignin (AIL). [Copyright &y& Elsevier]

Abstract: Microwave pyrolysis of distillers dried grain with solubles (DDGS) was investigated to determine the effects of pyrolytic conditions on the yields of bio-oil, syngas, and biochar. Pyrolysis process variables included reaction temperature, time, and power input. Microwave pyrolysis of DDGS was analyzed using response surface methodology to find out the effect of process variables on the biofuel (bio-oil and syngas) conversion yield and establish prediction models. Bio-oil recovery was in the range of 26.5–50.3wt.% of the biomass. Biochar yields were 23.5–62.2% depending on the pyrolysis conditions. The energy content of DDGS bio-oils was 28MJ/kg obtained at the 650°C and 8min, which was about 66.7% of the heating value of gasoline. GC/MS analysis indicated that the biooil contained a series of important and useful chemical compounds: aliphatic and aromatic hydrocarbons. At least 13% of DDGS bio-oil was the same hydrocarbon compounds found in regular unleaded gasoline. [Copyright &y& Elsevier]