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The synthesis of liquid fuel and fuel additives from abundant biomass substrates has acquired significant attention in recently. Among these value-added chemicals, 5-Ethoxymethylfurfural (5-EMF) is considered one of the most desirable gasoline alternatives because of its high stability, environmental friendliness, and high energy density of 8.7 kWhL−1. This 5-EMF could be directly produced from different biomass or biomass-derived substrates via etherification reactions in ethanol medium by straightforward synthetic methods using homogeneous catalysts and heterogeneous catalysts. In the current review, the role of different starting materials, homogeneous catalysts, and heterogeneous catalysts in the synthesis of 5-EMF is extensively discussed. Furthermore, the effect of different solvent system viz; single-phase, biphasic solvents, ionic liquids, and deep eutectic solvents (DES), on 5-EMF synthesis has also been discussed. The advantages and challenges of the chemocatalytic synthesis of EMF in different reaction systems are also discussed. We also tried to focus on the most economical way to produce EMF from HMF, and the mechanistic studies are summarized here along with catalyst deactivation data. [ABSTRACT FROM AUTHOR]

In the current work, the operating conditions for the Fischer–Tropsch process were optimized using experimental testing, kinetic modelling, simulation, and optimization. The experiments were carried out using a Ce-Co/SiO2 catalyst to examine how operating parameters affected the conversion of CO and product selectivity. A power-law kinetic model was used to represent the reaction rates in a mathematical model that was created to replicate the Fischer–Tropsch synthesis (FTS). It was decided to estimate the kinetic parameters using a genetic optimization technique. The developed model was validated for a range of operating conditions, including a temperature range of 200–240 °C, a pressure range of 5–25 bar, a H2/CO ratio of 0.5–4, and a space velocity range of 1000–5000 mL/gcat·h. The mean absolute relative error (MARE) between the experimental and predicted results was found to be 11.7%, indicating good agreement between the experimental data and the predicted results obtained by the mathematical model. Optimization was applied to maximize the production of liquid biofuels (C5+). The maximum C5+ selectivity was 91.66, achieved at an operating temperature of 200 °C, reactor total pressure of 6.29 bar, space velocity of 1529.58 mL/gcat·h, and a H2/CO feed ratio of 3.96. The practical implications of the present study are maximizing liquid biofuel production from biomass and municipal solid waste (MSW) as a renewable energy source to meet energy requirements, reducing greenhouse gas emissions, and waste management. [ABSTRACT FROM AUTHOR]

In the liquid biofuel production process, free fatty acids are important precursors for biodiesel and bio-aviation fuel. Enzymatic hydrolysis to produce free fatty acids has attracted more and more attention. However, enzymatic hydrolysis requires ensuring efficient expression of lipase and high product yield. In the shaking flask, the optimal addition amount of citric acid was 3 g/L, and the composition of composite amino acids was: histidine 0.1 mol/L, aspartic acid 0.03 mol/L and lysine 0.03 mol/L. On the basis of the shaking flask optimization, a 5 L fermentation tank was scaled up to obtain 25,000 U/mL of lipase after multiple batches of stable fermentation. This was the first time to cultivate Y. lipolytica using composite amino acid medium to produce high enzyme-activity lipase, demonstrating the industrial value of this lipase fermentation process. Finally, soybean oil was hydrolyzed to produce free fatty acids on a self-made static reactor. The optimized reaction conditions were: material flow rate 2813 mL/min, reaction temperature 45 °C, water content 25 wt% and lipase consumption 3 wt%. The yield of free fatty acids was 80.63% after 12 h under optimal reaction conditions in the self-made static reactor, 11.95% higher than that in the stirred reactor, which showed its industrial potential in the production of free fatty acids. [ABSTRACT FROM AUTHOR]

Environmental pollution and the depletion of fossil fuels have created a growing interest in the world community for renewable energy. Large-scale production of liquid biofuels is supported by governments. Iran is a developing country that supplies its energy needs from fossil fuels. However, clean energy must be used to prevent environmental pollution and ensure food security. In this study, with a case study of Golestan province as one of the leading provinces in the field of agriculture, the existing capacities in this country have been studied. The results showed that 58,945.95 tons of biodiesel and 527.55 million liters of bioethanol can be produced annually in this province. By creating suitable grounds for the production of this fuel, solving technological problems and the support of the people and the government of this province, it is able to supply 2% of the fuel of the country's gasoline engines. Also, the produced biodiesel can supply approximately 13% of the province's diesel. Reports indicate that it has the largest share in the production of liquid biofuels in the agricultural waste sector. [ABSTRACT FROM AUTHOR]

Liquid biofuels have emerged as a worldwide alternative fuel with potential to replace fossil fuels. Due to their wide availability as derivatives of organic materials from plants, they have attracted much attention and investment in developing countries including Tanzania, as alternative sources of energy. This study examined effects of oil quality from stem barks and phylloclades of Euphorbia tirucalli trees of different girth sizes (viz., 20 cm, 30 cm, 40 cm, 50 cm, 60 cm, 70 cm, and 80 cm) from semi-arid, coastal, and southern highlands in Dodoma, Dar es Salaam, and Mbeya Southern highland, agro-ecological zones in Tanzania. Using Soxhlet extraction method, oils were extracted from E. tirucalli stem barks with different girth sizes while oils from phylloclades were extracted from matured apical phylloclades collected from shoots of E. tirucalli trees from which the stem bark samples had been collected. Oil yields were determined by measuring the weight of oil (g) by the total weight of sample extracts used (20 g), and the average oil yield on each sample was determined. Oil quality was evaluated as oxidative stability index (OSI), acid values (AVs), and percent free fatty acids (%FFAs). Their results were then compared with the European Union (EU) oil quality standard specifications prescribed in EN 14214 of 6 h, 0.5 mg KOH/g, max and 0.020 maximum wt% limits, respectively. Differences in the quality of E. tirucalli (stem bark and phylloclades) oil were analyzed statistically with paired-sample t test (two-tailed) using the SPSS 15.0 software package. Results showed that the difference in OSIs from stem barks were not significantly higher (3–5 h) than phylloclades (3–4 h) at the p > 0.5 level. Also, the difference in AVs and %FFAs from the stem barks (7.6–7.4 mg KOH and 3.8–3.6%) was not significantly lower than those from the phylloclades (8.4–8.1 mg KOH and 4.3–4.0%) respectively. The quality of oil from stem bark and phylloclades samples at different stem girth sizes semi-arid agro-ecological zone was not significantly higher than from southern highland and coastal agro-ecological zones, respectively. Thus, there were no significant differences in the quality of E. tirucalli oil (stem bark and phylloclades) among stem girth sizes in different agro-ecological zones. The AVs and %FFAs of oils from stem bark and phylloclades were higher than the recommended standards, while the OSIs were below the biofuel standard limit. High AVs and %FFAs reduced oil quality by producing considerably low OSIs values than recommended standards. Finally, the study concluded that E. tirucalli oil requires purification to reduce levels of AV and %FFA contents so that the oil becomes suitable for application as liquid biofuel for energy generations. [ABSTRACT FROM AUTHOR]

In the current work, the operating conditions for the Fischer–Tropsch process were optimized using experimental testing, kinetic modelling, simulation, and optimization. The experiments were carried out using a Ce-Co/SiO2 catalyst to examine how operating parameters affected the conversion of CO and product selectivity. A power-law kinetic model was used to represent the reaction rates in a mathematical model that was created to replicate the Fischer–Tropsch synthesis (FTS). It was decided to estimate the kinetic parameters using a genetic optimization technique. The developed model was validated for a range of operating conditions, including a temperature range of 200–240 °C, a pressure range of 5–25 bar, a H2/CO ratio of 0.5–4, and a space velocity range of 1000–5000 mL/gcat·h. The mean absolute relative error (MARE) between the experimental and predicted results was found to be 11.7%, indicating good agreement between the experimental data and the predicted results obtained by the mathematical model. Optimization was applied to maximize the production of liquid biofuels (C5+). The maximum C5+ selectivity was 91.66, achieved at an operating temperature of 200 °C, reactor total pressure of 6.29 bar, space velocity of 1529.58 mL/gcat·h, and a H2/CO feed ratio of 3.96. The practical implications of the present study are maximizing liquid biofuel production from biomass and municipal solid waste (MSW) as a renewable energy source to meet energy requirements, reducing greenhouse gas emissions, and waste management.

This study investigates the effects of catalyst preparation techniques on the yield and quality of liquid biofuel produced from slow catalytic pyrolysis of microalgae Chlorella sp. using various catalysts, including acid catalysts (HZSM-5) and base catalysts (activated carbon). The effects of different temperatures, catalyst loading, and reaction time on the yield and quality of liquid biofuels, including chemical composition, density, and the resulting viscosity at the optimal variable, were investigated. The results showed that slow catalytic pyrolysis using 1 wt.% activated carbon catalyst, a temperature of 550°C, and a reaction time of three hours produced a maximum yield of liquid biofuel at 50.38 wt.% with high aromatic hydrocarbons, less oxygen and acid, a density of 0.88 kg/L, and a viscosity of 5.79 cSt that satisfied specifications of biodiesel No. 2. Slow catalytic pyrolysis with a variety of catalyst types and catalyst preparation techniques affects the increase in yield and quality adjustment of liquid biofuel. The proposed technology can be further developed for commercial applications, replacing conventional diesel fuel.

In the liquid biofuel production process, free fatty acids are important precursors for biodiesel and bio-aviation fuel. Enzymatic hydrolysis to produce free fatty acids has attracted more and more attention. However, enzymatic hydrolysis requires ensuring efficient expression of lipase and high product yield. In the shaking flask, the optimal addition amount of citric acid was 3 g/L, and the composition of composite amino acids was: histidine 0.1 mol/L, aspartic acid 0.03 mol/L and lysine 0.03 mol/L. On the basis of the shaking flask optimization, a 5 L fermentation tank was scaled up to obtain 25,000 U/mL of lipase after multiple batches of stable fermentation. This was the first time to cultivate Y. lipolytica using composite amino acid medium to produce high enzyme-activity lipase, demonstrating the industrial value of this lipase fermentation process. Finally, soybean oil was hydrolyzed to produce free fatty acids on a self-made static reactor. The optimized reaction conditions were: material flow rate 2813 mL/min, reaction temperature 45 °C, water content 25 wt% and lipase consumption 3 wt%. The yield of free fatty acids was 80.63% after 12 h under optimal reaction conditions in the self-made static reactor, 11.95% higher than that in the stirred reactor, which showed its industrial potential in the production of free fatty acids.

For the future energy markets, where the role of fossil fuels will be minimized and district heating systems will become more efficient through the use of waste streams, a new concept is proposed based on tri-generation of Fischer–Tropsch (FT) products, heat, and power. The challenge of combining the transport sector with a District Heating (DH) network and power grid is presented in this article by discussing the operating modes of the gasifier, FT product output (as a raw material for refinery) and waste stream generated after the synthesis reactor, preliminary process management schemes, market factors, and economic attractiveness. The feasibility of the concept was examined for an existing combined heat and power plant in Lithuania, which could become a potential demo plant. To demonstrate the feasibility of this concept, which may help create independence from fossil fuels through the use of syngas (for a sudden increase in heat demand), a techno-economic assessment was performed. The analysis of various scenarios showed that the cost of the FT product may be between 0.67 and 1.47 €/kg for gasifier capacities ranging from 10 to 40 MW. However, the economic attractiveness assessment revealed that the concept is profitable at a liquid biofuel (FT product) prime cost below 1.07 €/kg (without electrolysis capability). [ABSTRACT FROM AUTHOR]

This study investigates the effects of catalyst preparation techniques on the yield and quality of liquid biofuel produced from slow catalytic pyrolysis of microalgae Chlorella sp. using various catalysts, including acid catalysts (HZSM-5) and base catalysts (activated carbon). The effects of different temperatures, catalyst loading, and reaction time on the yield and quality of liquid biofuels, including chemical composition, density, and the resulting viscosity at the optimal variable, were investigated. The results showed that slow catalytic pyrolysis using 1 wt.% activated carbon catalyst, a temperature of 550°C, and a reaction time of three hours produced a maximum yield of liquid biofuel at 50.38 wt.% with high aromatic hydrocarbons, less oxygen and acid, a density of 0.88 kg/L, and a viscosity of 5.79 cSt that satisfied specifications of biodiesel No. 2. Slow catalytic pyrolysis with a variety of catalyst types and catalyst preparation techniques affects the increase in yield and quality adjustment of liquid biofuel. The proposed technology can be further developed for commercial applications, replacing conventional diesel fuel. [ABSTRACT FROM AUTHOR]

[Display omitted] • A high-quality liquid biofuel was successfully formulated from WCO biodiesel oil, distilled Yang-Na oil, and petroleum diesel oil. • The liquid biofuel was efficiently utilized in a small agricultural diesel engine with efficiency levels equivalent to a commercial B10 petroleum diesel oil. • The blended fuel can offer cost-effective and sustainable energy for agricultural countries, reducing their reliance on foreign petroleum sources and enhancing energy security through domestic resources. This study reports a highly efficient and cost-effective liquid biofuel for agricultural diesel engines by a ternary blending of waste cooking oil (WCO) biodiesel, distilled Yang-Na oil, and petroleum diesel oil. Biodiesel oil from WCO synthesized by NaOH-catalyzed pilot plant-scale solar reactor exhibited fuel properties that met ASTM-D6751 and EN-14214 standards. Crude Yang-Na was distilled at 280 oC to obtain distilled Yang-Na oil with major components of α-Gujernene (63.07 wt.%), α-Caryophyllene (19.08 wt.%), γ-Gujernene (5.16 wt.%), and γ-Elemene (5.23 wt.%), along with 7.46 wt.% of other hydrocarbon compounds. The ternary blendings of waste cooking oil (WCO) biodiesel, distilled Yang-Na oil, and petroleum diesel oil were formulated (50:30:20 and 50:25:25) and their physicochemical properties were evaluated and compared with a commercial B10 petroleum diesel oil. The formulated liquid biofuels met standards and closely resembled petroleum diesel with a viscosity of 3.86 cSt, density value of 876 kg m-3, and heating values of 9991 kcal/kg. The performance testing of the blended fuels in a small agricultural diesel engine showed the efficiency levels matched with a commercial B10 petroleum diesel oil and outperformed individual biodiesel and distilled Yang-Na oil. Variances in Brake Power and Brake Specific Fuel Consumption were <1% with low emissions of CO 2 , CO, HC, and NO x , while Engine Torque and biofuel consumption during cultivation showed differences of 3.42% and 2.54%, respectively. Accordingly, the obtained blended fuel is a promising option for community resource utilization, offering an alternative energy source for future communities. [ABSTRACT FROM AUTHOR]

Due to the worldwide increase in the demands for bioenergy sources to replace fossil fuels. Euphorbia tirucalli oil produced by stems and modified leaves (phylloclades) is a valuable liquid fuel as an alternative energy source for biofuel production. In this study, E. tirucalli oils were extracted from stem barks with varying stem girths (20cm–80cm) and fully grown apical phylloclades. Soxhlet apparatus was used in oil extraction according to Luque de Castro and García (2000). The percentage (%) oil yield was calculated by the weight of extracted oil to the total weight of the dried sample (20g). The study hypothesized that significantly higher oil yields would be obtained from larger stem girths than phylloclades of the same trees in different Agro-Ecological Zones (AEZs). Likewise, the difference in oil yields was higher in the Semi-arid AEZ than in the Southern highland and the Coast AEZs (p > 0.05). Results showed slightly higher oil yields from large stem girths [16.47% ± 0.34%/(20g) max ≡ 82.35% ± 0.34%/(100g) max] than phylloclades [15.7% ± 0.49%/(20g) max ≡ 78.5% ± 0.34%/(100gmax] in different AEZs. Oil yields from Semi-arid [82.35% ± 0.34%/(100g) max and 78.5% ± 0.49%/(100g) max] were slightly higher than Southern highland [79.0% ± 0.34%/(100g) max and 76.4% ± 0.49%/(100g) max] and the Coast [76.4% ± 0.34%/(100g) max and 70.25% ± 0.49%/(100g) max] AEZ. But the difference in oil yields was not significant (p > 0.05). Results exhibited increasing patterns in the percentage (%) oil yields from low (20cm) to larger (80cm) stem girths. High oil yields between stem girths (82.35%) and phylloclades (78.5%) suggest that E. tirucalli oil is suitable for liquid biofuel production as an energy source in Tanzania.

The necessity to find renewable and low carbon fuels as a critical component of the strategy to reduce greenhouse gas emissions in Canada has caused the biofuels industry to rapidly expand. However, there is a higher capacity for the use of biofuels to replace conventional petroleum fuels in Canada than outlined by cur rent regulations and programs. A wide range of feedstocks, processes, and applications for liquid biofuels can be found in Canada at varying degrees of progress. To reach the full potential of the biofuels industry in Canada, it is important to understand the broad landscape of the biofuels industry and areas of promise. The objective of this paper is to provide a comprehensive overview of the current state of liquid biofuels in Canada. This includes national feedstock availability and conversion processes to produce liquid biofuels. Both biochemical and thermochemical processes over a wide range of technology readiness levels, from R&D to commercialization, will be included. Current industry, government, and/or academic support for these production activities will b e referenced where applicable. The transportation applications of commercially available liquid biofuels in Canada will be reviewed. Finally, comments on future prospects to boost environmental and economic competitiveness of the biofuels industry in Canada will be provided.

The article is devoted to the issues of the current state of obtaining environmentally friendly liquid biofuel (bio-oil) from lignocellulosic biomass by its thermochemical conversion, as well as the prospects for the development of this direction in the near future. At present, thermochemical conversion of plant biomass (fast pyrolysis), which contains a large amount of lignocellulose, into liquid biofuel is one of the developing directions for involving unconventional energy sources into the energy balance of Ukraine. In this regard, it is of interest to assess the current state of the development of industrial production of liquid biofuel from plant biomass lignocellulose and further prospects in this branch of bioenergy. For this purpose, based on the study of scientific bibliography concerning the problem of liquid biofuel production, the existing experience of various countries in the industrial production of biodiesel fuel by the fast pyrolysis method is analyzed and the possibility of using lignocellulosic biomass as a raw material for its production is shown. It also provides information on technologies that have reached the industrial level. It has been established that the technology for producing biofuel from lignocellulosic biomass is widespread in many countries of the world. The paper describes the technological scheme of fast pyrolysis of wood and the main stages of production. It is shown that using the technology of thermochemical conversion of lignocellulosic biomass, it is possible to obtain a high-quality hydrocarbon product - bio-oil, and a description of the main advantages of this product is given. As a result of the work, it was established that the technology of bio-oil production from lignocellulosic biomass by the method of fast pyrolysis has broad prospects for further development. The results obtained by the authors of the article can be used in the further study of issues related to the thermochemical conversion of biomass into liquid biofuel. Ref. 12. [ABSTRACT FROM AUTHOR]

It is obvious that Iran agricultural industry, unlike Brazil and USA, cannot afford to provide conventional biomass, i.e. sugary or starchy biomass for bioethanol production, mainly due to climatic and geographic conditions. With some exception of date (fruit), first-generation ethanol production triggers food vs. fuel debates in Iran and put nation to hunger. Agricultural products including apple, barley, carrot, corn, grape, orange, potato, rice, sugar beet, sugarcane, and wheat are consumed domestically, exported, or even lost because of poor harvesting and processing conditions such as transportation or packaging. These products may alone generate 21.56 million ton per annum green wastes upon processing in the food industry. Every year about 5.4 billion liters of bioethanol can be produced by establishing second-generation ethanol plants next to the food processing sectors. Seventy-seven-percent of this amount of bioethanol can easily support 5% ethanol (E5) policy to phase out the consumption of 4.2 billion liters methyl tert-butyl ether (MTBE) for raising the octane number of gasoline in the country. If more comprehensive policy is adopted, larger quantities of lignocellulosic feedstocks can be gathered from agro as well as forestry practices. Second-generation bioethanol technology can help Iran to tackle air pollution in its big cities and to address the adverse effects of MTBE on its populations and ecosystem. The other advantages are improvement of fuel security, mitigation of climate change, and development of economy. The motivation can be created through passing a framework policy to cut fossil fuel subsidies, to mandate bioethanol blends in gasoline, and to impose carbon taxes. Development of coherent socially and environmentally relevant strategies and facilitation of investment in bioethanol industry are also necessary. • Agro-food industry generates more than 21.56 million ton wastes each year in Iran. • 5.4 billion liters of ethanol can be obtained annually by conversion of Iranian wastes. • Iranian law-makers must mandate the use of ethanol or its derivatives in gasoline. • 4.2 billion liters of MTBE can be replaced annually by bioethanol in Iran. • Higher ethanol ratios in gasoline can efficiently reduce air pollution in big cities. [ABSTRACT FROM AUTHOR]

In the light of the growing importance of biofuels in the world and Ukraine's potential for its production, the current research focuses on analysing future development of liquid biofuel market and production possibilities in Ukraine until 2030 using the AGMEMOD model. The AGMEMOD model is an econometric, dynamic, partial equilibrium, multi-commodity model which has the capacity to evaluate changes in Ukrainian agricultural policy and the impacts of political decisions on the agricultural sector in Ukraine. The current paper offers an introduction of state aid in the form of direct support and tax preferences for liquid biofuels producers to meet the needs of the domestic market in biofuels and to achieve the indicative target of 10% consumption biofuels in the total consumption of motor fuel by transport sector till 2020. For the quantitative assessment of these effects, the AGMEMOD model was used. The results of this study indicate that implementation of the direct state support, introduction of the system of returning and cancelling excise duty for biofuels producers will stimulate the achievement of the indicative target of 10% biofuels' consumption by the transport sector. [ABSTRACT FROM AUTHOR]

This paper reports experimental measurements of the radiation characteristics of green algae used for carbon dioxide fixation via photosynthesis. The generated biomass can be used to produce not only biofuels but also feed for animal and food supplements for human consumptions. Particular attention was paid to three widely used species namely Botryococcus braunii, Chlorella sp., and Chlorococcum littorale. Their extinction and absorption coefficients were obtained from normal–normal and normal–hemispherical transmittance measurements over the spectral range from 400 to 800 nm. Moreover, a polar nephelometer was used to measure the scattering phase function of the microorganisms at 632.8 nm. It was observed that for all strains, scattering dominates over absorption. The magnitudes of the extinction and scattering cross-section are functions of the size, shape, and chlorophyll content of each strain in a non-trivial manner. Absorption peaks at 435, 475, and 676 nm corresponding to chlorophyll a and chlorophyll b. The results can be used for scaling and optimization of CO2 fixation in ponds or photobioreactors as well as in the development of controlled ecological life support systems.

The use of fossil hydrocarbons is accompanied by such problems as the depletion of energy resources and high levels of anthropogenic emissions. One of the options for solving these problems can be the involvement in the fuel sector of composite mixed fuels using gas hydrates and vegetable liquid bio-fuels. In this research we test a hypothesis that gas hydrate with added rapeseed oil will make an energy-efficient and environmentally friendly composite fuel. According to the experimental findings, the co-combustion of gas hydrates and liquid biofuels shows high potential. It shortens the ignition delay by 1.5 times at 700 °C in the combustion chamber and by half at 800 °C compared with the combustion of methane hydrate alone. It also produces 18–32% less carbon monoxide, 12–22% less nitrogen oxides, and 14–33% less sulfur oxides than the direct combustion of rapeseed oil. On the basis of the results obtained, we have developed a predictive mathematical model simulating the heat transfer in a layer of composite fuel. A methane hydrate and rapeseed oil mixing scheme is proposed for combustion chambers. We also provide recommendations on how to use the research findings in a number of energy-related applications. [Display omitted] [ABSTRACT FROM AUTHOR]

There are presented the results of the bibliographical and theoretical research of the methods of liquid substances dosage. Based on the research were elaborated the method and continuing dosage installation of multicomponent mixtures to obtain liquid biofuel of high quality and minimum cost. In the proposed "Biomixt" installation the liquids flow is provided by the pressure reduction (suction) at the pump inlet. The theoretical analysis and experimental research of the installation allowed the justification of hydrodynamic parameters (cross-sectional area S of the pipes, pressure difference Δр, type of fluid flow Re>104), that provides the needed ratio of the components with the error δ<0.5%. [ABSTRACT FROM AUTHOR]

Abstract The production of substitutes for liquid fossil fuels is of utmost importance for the decarbonization of the transport sector. This paper assesses the economic feasibility of producing hydrotreated vegetable oil (HVO) using waste vegetable oils as feedstock. The supply of hydrogen for the upgrading of the oil is obtained through a high-temperature electrolysis process, fed by low-carbon electricity. The use of waste materials eliminates the competition with food crops (e.g. soybean or rapeseed) and promotes the recycle of substances that should be treated for disposal. The results of the study show that the production cost of HVO with the considered plant are around 33% higher than that of fossil diesel. Moreover, the variable that has the strongest impact on the production cost of HVO is the price of the waste vegetable oil, which affects the final results more than the electricity price and the cost of the electrolyser. [ABSTRACT FROM AUTHOR]

Technical lignin, which can be potentially obtained in large amounts as a by-product from kraft pulping, represents a potential resource for manufacturing fuels and chemicals. Upgrading of lignin, by lowering its molecular weight, is a valuable alternative to precipitation from black liquor, which occurs in the Lignoboost process. The solubility properties of Lignoboost lignin and filtered lignin in a number of technically feasible solvents were compared, and it was found that both lignins were dissolved in similar solvents. With the exception of furfural, the best lignin solvents generally were organic solvents miscible with water, such as methanol. It was possible to dissolve more filtered lignin in higher concentrations than Lignoboost lignin; additionally, the viscosities of the filtered lignin solutions were also considerably lower than those of Lignoboost lignin, especially at higher concentrations. Methods for non-organic component removal from filtrated lignin were tested, and it was concluded that several cold acidic treatments after dewatering can lower the ash content to values below 0.5% by weight.

Transport is one of the sectors of the energy consumption where the presence of renewable energies is lower and its increase is hard to achieve especially in countries that import all the fuels that they consume. This paper addresses the progress that Portugal is making toward a more sustainable transport sector. A near- and medium- term scenario analysis is performed, based on the energy consumption in the past and on a detailed evaluation of the trends for renewable energy in the transport sector. The near-term scenarios aim at portraying the conditions that allow the country to fulfill the target of 10% renewable share in transportation established by the European Union. The medium-term scenarios highlight the implications, in terms of emission reduction and of energy independence, deriving from the use of electric vehicles and natural gas, synthetic and fossil, as alternatives to liquid fuels. The results show that electric vehicles would substantially reduce the total energy consumption and the greenhouse gas emissions, while the promotion of routes for synthetic natural gas would contribute to taking advantage of local resources. The paper also provides some insights about the design of future policies to build a more sustainable transport sector. [ABSTRACT FROM AUTHOR]

Naphthalene as a fuel additive to ethanol was examined in a swirl combustor with the objective to obtain efficient burning and ultra-low emissions using different heating value fuels. Naphthalene is a polyaromatic compound often regarded as a waste fuel that results in high levels of pollutants emission. The effectiveness of naphthalene as a fuel additive to ethanol on NO and CO emissions and stability was determined. The naphthalene concentration was varied from 0 to 0.4 mol/L in ethanol, corresponding to a heating value increase of 8.8% on a volumetric basis (or 5.7% on mass basis). Emissions data were reported for Colorless Distributed Combustion (CDC) using N 2 /CO 2 dilution, at equivalence ratios (Φ) of 0.9 and 0.7. The data under normal fuel–air combustion conditions also reported, clearly showing the benefits of CDC. NO and CO emission below 1 and 6 ppm, respectively, were achieved under CDC conditions for each of the naphthalene-ethanol fuels examined. The results at both the equivalence ratios showed lower NO emission with increase in naphthalene concentration, which provided higher heating value fuel mixture. The CO emission was also low and remained negligibly unchanged with change in naphthalene concentration and equivalence ratio. The results show the use of naphthalene addition to ethanol for increased heating value fuel with ultra-low emissions and higher stability under distributed combustion conditions. [ABSTRACT FROM AUTHOR]

The article provides the analysis of production and usage of sustainable liquid fuels (biodiesel and bioethanol) in Lithuania in compliance with the National Energy Strategy and European policy. With regard to the principles of economic, environmental and social sustainable development and evaluating biofuel supply sources, the national aim is to reduce greenhouse gas emissions and the consumption of fossil fuel, especially in transport sector. The use of alternative fuels in the EU-28 is regulated by Directives, and in many countries, liquid biofuels are blended with mineral fuels. In Lithuania, the share of liquid biofuels reached 5.75% of the total volume of transport fuel in 2010, and this share should increase to 10% until 2020. In the Baltic States, as well as in other East European countries (Finland and others), biodiesel is produced mainly from the rapeseed oil and bioethanol – from the starch containing cereals (wheat, triticale, etc.), sugar beet or potatoes. Lithuania promotes production of liquid biofuel via economic and legal measures. Revised legislation provides favourable conditions for the development of biofuel production. Established biofuel production framework exceeds the capacities, which are required by Lithuania's obligations, related to liquid biofuel consumption in transport sector. In the article, the liquid biofuel production and the tasks for reduction of GHG emissions in the EU and Lithuania were overviewed. The analysis of biofuel production and policy in Lithuania was carried out. Energy from RES and the share of liquid biofuels were investigated. The trends of the liquid biofuel production and consumption were reviewed. The selection of biofuel feedstock was disclosed. The legislations regulating production and consumption of biofuels in Lithuania were shown. The evaluation of biofuels impact on environmental pollution was performed. National policy regarding the increase of biofuels use in Lithuania was presented. [ABSTRACT FROM AUTHOR]

In the ever-increasing demand for alternative fuels, one promising solution is the partial substitution of conventional fossil fuel with biofuel rather than completely replacing it. In this experimental study, a 300 kW th (thermal power) oil-fired furnace is fueled with blends of crude castor oil and diesel to examine the feasibility of using these blends as a substitute for pure diesel in industrial applications. Castor oil is derived from castor seeds, which possesses low heating value, high oxygen content and high viscosity. A furnace test was conducted for pure diesel and castor oil/diesel blends with various mixing ratios. Pure diesel and blends with 5%, 10%, 20% and 30% castor oil were comparatively investigated by focusing on wall temperatures in the radiative section of the furnace, gas temperatures in the convective section and emission products from combustion. All experiments were performed under the operating condition of optimum (minimum) excess O 2 concentration in the flue gas. The air supply rates for the minimum excess oxygen requirement were 245, 241, 240, 237 and 236 Nm 3 /h, respectively, for pure diesel and 5%, 10%, 20% and 30% blended castor oil at the fixed liquid-fuel supply rate of 20 L/h. Excellent stable combustion was observed during the experiments with the castor oil/diesel blended fuels. Both the wall temperature and gas temperature dropped slightly with increases in castor oil content in the blends; nevertheless, they were very close compared with pure diesel. Additionally, with increasing castor oil content in the blends, NO and CO emissions only slightly decreased and increased, respectively. Accordingly, it is verified that the use of 5–30% castor oil in the blends produces similar furnace temperature distributions and comparable emission levels of CO, NO and SO 2 when compared to pristine diesel. [ABSTRACT FROM AUTHOR]

Liquid furanic hydrocarbons, a class of biomass-based fuels and chemicals, are typically required to achieve moderate product selectivity and yield under harsh conditions (e.g., high temperature and H 2 pressure) involving multi-step processes over different catalysts. In this study, a single-step catalytic process was developed for direct conversion of various saccharides to furanic biofuels such as 2,5-dimethylfuran and 2-methylfuran with high yields (>95%) at 110–130 °C. The negatively charged hydride (H − ) of readily available polymethylhydrosiloxane (PMHS) acting as green H-donor over hydrophobic Pd nanoparticles did not obstruct upstream reactions (e.g., hydrolysis, isomerization and dehydration) for the in situ formation of furanic aldehydes/alcohols from sugars, and could selectively facilitate the subsequent hydrodeoxygenation of carbonyl and hydroxyl groups other than the furanic ring in one pot, as clarified by deuterium-labeling study. Importantly, the unreduced Pd(II) nanocatalysts also exhibited comparable performance in the selective hydrodeoxygenation reaction. Moreover, the catalytic strategy was extended to various carboxides for quantitative production of corresponding furanic/aromatic hydrocarbons at room temperature that were more pronounced than previously reported results, and the optimal Pd/MIL-53(Al) coated with polydimethylsiloxane (Pd/MIL-53(Al)-P) was highly stable with little deactivation and Pd leaching for at least five consecutive cycles. [ABSTRACT FROM AUTHOR]

Biomass production for bioenergy use may contribute to rural development by increasing household incomes, local employment and energy supply, especially in developing countries. This paper presents a value-chain approach to evaluating the profitability and competitiveness of producing biodiesel or ethanol. We apply a ‘rapid appraisal’ accounting framework to the case of Tanzania, which is a data scarce setting and therefore well-suited to the proposed approach. The framework also estimates the number of jobs created in the biofuel sector under different production arrangements and related demand for land resource. We evaluate the potential trade-offs between different scales of biofuel production (both the scale of feedstock production and biofuel processing). We find that only sunflower-biodiesel is profitable, especially if produced in large-scale estate farming systems. Estate farming is the best option for profits and competitiveness, even if domestic biofuel production is never competitive on the international market for energy. We also find that the number of jobs depends crucially on the involvement of smallholders. Establishing out-grower schemes (or similar arrangements), rather than estate farms, should be a key policy objective if biofuels production is going to improve rural economy. However social benefits may be gained at a cost of reduced international competitiveness and increased land exploitation. [ABSTRACT FROM AUTHOR]

This paper presents a heuristic methodology for estimating the possible variation of the liquid biofuel potential of a region, an appraisal made for a future period of time. The determination of the liquid biofuel potential has been made up either on the account of an average (constant) yield of the energetic crops that were used, or on the account of a yield that varies depending on a known trend, which can be estimated through a certain method. The proposed methodology uses the variation of the yield of energetic crops over time in order to simulate a variation of the biofuel potential for a future ten year time period. This new approach to the problem of determining the liquid biofuel potential of a certain land area can be useful for investors, as it allows making a more realistic analysis of the investment risk and of the possibilities of recovering the investment. On the other hand, the presented methodology can be useful to the governmental administration in order to elaborate strategies and policies to ensure the necessity of fuels and liquid biofuels for transportation, in a certain area. Unlike current methods, which approach the problem of determining the liquid biofuel potential in a deterministic way, by using econometric methods, the proposed methodology uses heuristic reasoning schemes in order to reduce the great number of factors that actually influence the biofuel potential and which usually have unknown values. [ABSTRACT FROM AUTHOR]

Technical lignin, which can be potentially obtained in large amounts as a by-product from kraft pulping, represents a potential resource for manufacturing fuels and chemicals. Upgrading of lignin, by lowering its molecular weight, is a valuable alternative to precipitation from black liquor, which occurs in the Lignoboost process. The solubility properties of Lignoboost lignin and filtered lignin in a number of technically feasible solvents were compared, and it was found that both lignins were dissolved in similar solvents. With the exception of furfural, the best lignin solvents generally were organic solvents miscible with water, such as methanol. It was possible to dissolve more filtered lignin in higher concentrations than Lignoboost lignin; additionally, the viscosities of the filtered lignin solutions were also considerably lower than those of Lignoboost lignin, especially at higher concentrations. Methods for non-organic component removal from filtrated lignin were tested, and it was concluded that several cold acidic treatments after dewatering can lower the ash content to values below 0.5% by weight. [ABSTRACT FROM AUTHOR]

The rural community still lacks access to clean, cost effective and sustainable form of energy that is needed to power their socio-economic activities, particularly for agriculture, water supply and food processing. Understanding that energy has a close link with poverty reduction, economic growth and sustainable development, a study on the process of modifying plant oil (PO) to produce a suitable liquid biofuel that can run diesel engines commonly used in rural areas for various social-economic activities was carried out. The research was part of works by Policy Innovation System for Clean Energy Security (PISCES) research project, which was a five-year initiative project funded by the UK's Department for International Development (DFID). PISCES, which had partners in Kenya, India, Sri Lanka, United Kingdom and Tanzania, intended to provide policy makers with information and approaches that can unlock the potential of bioenergy to improve energy access and livelihoods in rural communities. The PO used was indigenous non-edible oil from Jatropha (Jatropha Curcas L.) seeds. Modified Plant Oil (MPO) presents a potential clean, cost-effective, sustainable and accessible fuel to meet rural basic energy needs. MPO can also power rural agroprocessing activities by being used in power tillers, millers, water pumps, etc., and become an important key for socio-economic development of rural population relying on agricultural activities. The use of renewable energy from PO will contribute to sustainable energy source and to reduce CO2 emission, contributing to reduce climate change problems. [ABSTRACT FROM AUTHOR]