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Rapeseed is currently cultivated as an industrial crop in Latvia as a source of oil rich biomass to contribute to renewable energy goals of the European Union. However, rapeseed oil can also be used as a feedstock biobased polyurethane production. Latvian State Institute of Wood Chemistry have developed polyols based on rapeseed oil and have developed biobased and volatile organic compounds-free polyurethane coatings. The main aim of this study was to present a Life Cycle Inventory of spring and winter rapeseed produced in Northern European country Latvia based on primary data of agricultural practices used in this region. The study was carried in accordance with ISO 14040 and ISO 14044. Data were collected from a large crop company in Latvia to ensure a specific and accurate data collection for the definition of the complete supply chain. The reference unit of this study was defined as 1 ha, time horizon 2008–2016, stages from the raw materials production to the seed harvesting were considered. The data presented will add to and expand the existing knowledge of rapeseed production in other European countries. Lastly, this paper is the first in a series of papers that will result in a complete Life Cycle Assessment for these develop polyurethane coatings based on rapeseed oil polyols to avoid black box unit process and provide transparent results. [ABSTRACT FROM AUTHOR]

Abstract: The depleting fossil fuels with their ever increasing prices have paved ways for alternative fuels. Biodiesel is one of those alternative fuels which have picked up keen interest of the people due to its similar properties to diesel. However due to biodiesel being costlier than diesel in the present scenario, it has not been preferred to diesel. However if the cost of biodiesel is reduced then its effective usage can be made, either by blending with conventional diesel or by utilizing its byproduct (glycerol) effectively. One way is to use glycerol to produce hydrogen. Hydrogen, being another source of renewable energy, is also seen as a clean fuel for transportation purpose. Hydrogen can be prepared through glycerol via various routes namely steam reforming, auto-thermal reforming, partial oxidation, etc. The paper here focuses on the steam reforming process. This process is used widely used in the industries and it would not require much change in the system if the feedstock is changed to glycerol from naphtha or natural gas. However like every process this process also has some limitations which hinder the effective production of hydrogen. The paper throws light on these challenges, along with few possible solutions which can be used in order to avoid or eliminate these challenges and help in efficient production of hydrogen. [Copyright &y& Elsevier]

Abstract: In recent years, environmental problems caused by the use of fossil fuels and the depletion of petroleum reserves have driven the world to adopt biodiesel as an alternative energy source to replace conventional petroleum-derived fuels because of biodiesel''s clean and renewable nature. Biodiesel is conventionally produced in homogeneous, heterogeneous, and enzymatic catalysed processes, as well as by supercritical technology. All of these processes have their own limitations, such as wastewater generation and high energy consumption. In this context, the membrane reactor appears to be the perfect candidate to produce biodiesel because of its ability to overcome the limitations encountered by conventional production methods. Thus, the aim of this paper is to review the production of biodiesel with a membrane reactor by examining the fundamental concepts of the membrane reactor, its operating principles and the combination of membrane and catalyst in the catalytic membrane. In addition, the potential of functionalised carbon nanotubes to serve as catalysts while being incorporated into the membrane for transesterification is discussed. Furthermore, this paper will also discuss the effects of process parameters for transesterification in a membrane reactor and the advantages offered by membrane reactors for biodiesel production. This discussion is followed by some limitations faced in membrane technology. Nevertheless, based on the findings presented in this review, it is clear that the membrane reactor has the potential to be a breakthrough technology for the biodiesel industry. [Copyright &y& Elsevier]

Abstract: In the last few years, biodiesel has emerged as one of the most potential renewable energy to replace current petrol-derived diesel. It is a renewable, biodegradable and non-toxic fuel which can be easily produced through transesterification reaction. However, current commercial usage of refined vegetable oils for biodiesel production is impractical and uneconomical due to high feedstock cost and priority as food resources. Low-grade oil, typically waste cooking oil can be a better alternative; however, the high free fatty acids (FFA) content in waste cooking oil has become the main drawback for this potential feedstock. Therefore, this review paper is aimed to give an overview on the current status of biodiesel production and the potential of waste cooking oil as an alternative feedstock. Advantages and limitations of using homogeneous, heterogeneous and enzymatic transesterification on oil with high FFA (mostly waste cooking oil) are discussed in detail. It was found that using heterogeneous acid catalyst and enzyme are the best option to produce biodiesel from oil with high FFA as compared to the current commercial homogeneous base-catalyzed process. However, these heterogeneous acid and enzyme catalyze system still suffers from serious mass transfer limitation problems and therefore are not favorable for industrial application. Nevertheless, towards the end of this review paper, a few latest technological developments that have the potential to overcome the mass transfer limitation problem such as oscillatory flow reactor (OFR), ultrasonication, microwave reactor and co-solvent are reviewed. With proper research focus and development, waste cooking oil can indeed become the next ideal feedstock for biodiesel. [Copyright &y& Elsevier]

Abstract: Biodiesel is a low-emissions diesel substitute fuel made from renewable resources and waste lipid. The most common way to produce biodiesel is through transesterification, especially alkali-catalyzed transesterification. When the raw materials (oils or fats) have a high percentage of free fatty acids or water, the alkali catalyst will react with the free fatty acids to form soaps. The water can hydrolyze the triglycerides into diglycerides and form more free fatty acids. Both of the above reactions are undesirable and reduce the yield of the biodiesel product. In this situation, the acidic materials should be pre-treated to inhibit the saponification reaction. This paper reviews the different approaches of reducing free fatty acids in the raw oil and refinement of crude biodiesel that are adopted in the industry. The main factors affecting the yield of biodiesel, i.e. alcohol quantity, reaction time, reaction temperature and catalyst concentration, are discussed. This paper also described other new processes of biodiesel production. For instance, the Biox co-solvent process converts triglycerides to esters through the selection of inert co-solvents that generates a one-phase oil-rich system. The non-catalytic supercritical methanol process is advantageous in terms of shorter reaction time and lesser purification steps but requires high temperature and pressure. For the in situ biodiesel process, the oilseeds are treated directly with methanol in which the catalyst has been preciously dissolved at ambient temperatures and pressure to perform the transesterification of oils in the oilseeds. This process, however, cannot handle waste cooking oils and animal fats. [Copyright &y& Elsevier]

Biodiesel is a renewable fuel that is commonly used in diesel engines around the world mostly in blends with the conventional diesel. There are many studies concerning its production and its properties and a series of them confirms the biodiesel advantages when compared with conventional diesel in relation of the environmental impacts. In spite of many advances concerning the biodiesel production and properties its behavior at low temperatures is worst than the conventional diesel, and, unfortunately, low temperature property information concerning fatty acid ethyl esters (FAEE) and the biodiesel is still scarce for researchers. This paper presents nine solid-liquid phase diagrams of FAEE binary mixtures to complement the studies of FAEE phase diagram previously reported. All of the phase diagrams have been determined using differential scanning calorimetry (DSC) and also modelled using both the Predictive UNIQUAC and the ideal solution models. The results have been shown good correlation between experimental and modelled data. [ABSTRACT FROM AUTHOR]

Biodiesel, a non-toxic biodegradable fuel from renewable sources such as vegetable oils, has been developed in order to reduce dependence on crude oil and enable sustainable development. The knowledge of phase equilibrium in systems containing compounds for biodiesel production is valuable, especially in the purification stage of the biodiesel. Nonetheless, the refining process of biodiesel and by-products can be difficult and can elevate the production costs considerably unless it has an appropriate knowledge about the phase separation behavior. In addition, the transesterification reaction yield for producing biodiesel depends upon several operation parameters e.g. the feed molar ratio oil-to-alcohol and the temperature. These parameters were analyzed through a thermodynamic analysis by direct Gibbs energy minimization method in this paper, with the purpose of calculating the chemical and phase equilibrium of some mixtures containing compounds found in biodiesel production. For this, optimization techniques associated with the GAMS ® 2.5 software were utilized and the UNIQUAC and NRTL models were applied to represent the non-idealities of the liquid phases. Also, binary interaction parameters of studied compounds were correlated for NRTL and UNIQUAC models by using the least squares principle. The results showed that the use of optimization techniques associated with the GAMS software are useful and efficient tools to calculate the chemical and phase equilibrium by minimizing the Gibbs energy. Moreover, a good agreement was observed in cases in which calculated data were compared with experimental data. [ABSTRACT FROM AUTHOR]

The use of liquid fossil fuel as an energy source has long been considered unsustainable and most importantly the liquid fossil fuel will be diminished by the middle of this century. In addition, the fossil fuel is directly related to environmental degradation and greenhouse emission. Biofuel produced from plants, animals or algae products can offer an alternative to reduce our dependency on fossil fuel and assist to maintain healthy global environment. Micro-algae is becoming popular candidate for biofuel production due to their high lipid contents, ease of cultivation and rapid growth rate. This paper reviews the current state-of-the-art of biofuel from algae as a renewable energy source. [ABSTRACT FROM AUTHOR]

Abstract: Alongside with biofuel development, social acceptance issues have been underestimated. While social acceptance can emerge as powerful barrier for biofuel development, this article provides discussion on social acceptance in biofuel context. An acceptance framework based on life cycle biofuel production had been referred for a better understanding on social acceptance issues. Malaysia has been referred for the discussion as the country has faced with acceptance issue in their biofuel program. The discussion point out different societal groups will demand specific consideration for either support or oppose biofuel. This paper concludes that biofuel development will be constraint if social acceptance issues remain neglect. [Copyright &y& Elsevier]

Abstract: This paper examines the competitiveness, role, and impact of microalgal biodiesel in the 21st century using a global energy system model with a detailed technological representation. The major conclusions are the following. First, the competitiveness of microalgal biodiesel decreases as CO2 stabilization constraints become more stringent. The share of microalgal biodiesel and renewable jet fuel produced from it in total global final energy consumption over the time horizon 2010–2100 is 5.1% in the case without CO2 constraints compared with 3.9% and 0.7% in the case of CO2 stabilization at 550ppmv and 400ppmv, respectively. This is because production and combustion of microalgal biodiesel release as much CO2 as is captured from anthropogenic sources and assimilated by microalgae and because CO2 prices raised by stringent CO2 stabilization constraints make the economics of microalgal biodiesel unattractive. Second, the competitiveness of microalgal biodiesel is also greatly affected by microalgal production cost and microalgal lipid yield. Under a 400ppmv CO2 stabilization constraint, a 50% microalgal production cost decrease leads to increase in total global microalgal biodiesel production over the time horizon by a factor of 6.5, while a 50% microalgal lipid yield increase leads to increase in it by a factor of 4.5. Third, microalgal biodiesel plays an important role in satisfying the energy demand in the transport sector, thereby replacing petroleum products and Fischer–Tropsch synfuels. An increasing proportion of microalgal biodiesel is converted into renewable jet fuel over time to be used as a fuel for aircraft. Fourth, either without CO2 constraints or under the 550ppmv CO2 stabilization constraint, the participation of microalgal biodiesel in the global energy market would have a large impact on the global energy supply and consumption structure. This is not only because of its substitution for other forms of final energy, but also because of the need to satisfy the demand for CO2 for microalgal production. [Copyright &y& Elsevier]

Abstract: In the production of biofuels for transport many critics have argued about the poor energy efficiency and environmental performance of the production industries. Optimism is thus set on the production of second generation biofuels, while first generation biofuels continue to dominate worldwide. Therefore it is interesting to consider how the environmental performance of first generation biofuel industries can be improved. The field of industrial symbiosis offers many possibilities for potential improvements in the biofuel industry and theories from this research field are used in this paper to highlight how environmental performance improvements can be accomplished. This comes in the form of by-product synergies and utility synergies which can improve material and energy handling. Furthermore, the processes and products can gain increased environmental performance improvements by the adaption of a renewable energy system which will act as a utility provider for many industries in a symbiotic network. By-products may thereafter be upcycled through biogas production processes to generate both energy and a bio-fertilizer. A case study of an actual biofuel industrial symbiosis is also reviewed to provide support for these theories. [Copyright &y& Elsevier]

Abstract: To meet the demand of its fast growing economy, China has become already the second largest buyer of crude oil. China is facing critical problems of energy shortage and environment deterioration. Rational and efficient energy use and environment protection are both getting more attention in China. Biomass energy is renewable energy made from biological sources. China''s biomass resources are abundant, which could provide energy for future social and economic development. However technologies for biomass resource conversion in China are still just beginning. In this paper, current biomass resource distribution and technologies of biomass energy, including power generation, biofuel production and biomass-based chemical production are reviewed. [Copyright &y& Elsevier]

Abstract: Biodiesel has received much attention in recent years. Although numerous reports are available on the production of biodiesel from vegetable oils of terraneous oil-plants, such as soybean, sunflower and palm oils, the production of biodiesel from microalgae is a newly emerging field. Microalgal biotechnology appears to possess high potential for biodiesel production because a significant increase in lipid content of microalgae is now possible through heterotrophic cultivation and genetic engineering approaches. This paper provides an overview of the technologies in the production of biodiesel from microalgae, including the various modes of cultivation for the production of oil-rich microalgal biomass, as well as the subsequent downstream processing for biodiesel production. The advances and prospects of using microalgal biotechnology for biodiesel production are discussed. [Copyright &y& Elsevier]

Abstract: Biodiesel is one of the candidates for alternative fuels since it is renewable, sustainable and produced from domestic or non-food crop resources with less detrimental environmental impact. There are several different approaches to the production process. In this paper a new production method, the supercritical methanol process, was investigated and its environmental performance was compared with the conventional alkali-catalyzed process using LCA as a tool. The supercritical process is technically a simpler production process and offers the advantages of higher yields and the production of less environmentally damaging wastes. However, it still generates a significantly higher environmental load since the methanol recovery unit requires a large amount of energy. [Copyright &y& Elsevier]

If the agricultural products market is limited and much of agricultural land is not utilized as is the case in many countries in the world at present, then agriculture should be directed to the production of new alternative products. The land can be used to produce non-food products including biodiesels for the domestic energy market to diminish imports. Much research has been done on biodiesels over the last 20 yr after the oil crisis in 1973. At present, concern about environmental regulations has been the major reason to look for alternative fuel. A significant level in terms of physico-chemical properties of biodiesel has been obtained but there is a lack of full or partial replacement of fossil fuel that needs to be discussed.This paper presents the experimental results carried out to evaluate the effect of anticorrosion additive in biodiesel (from palm oil) on diesel engines, performance, emissions and wear characteristics. This biodiesel is defined as the methyl ester of palm oil also known as palm oil diesel. The results of this investigation will be used to find compatible lubricant for biodiesel engine. [Copyright &y& Elsevier]