As the fossil fuels are depleting day by day, there is a need to find out an alternative fuel to fulfill the energy demand of the world. Biodiesel is one of the best available resources that have come to the forefront recently. In this paper, a detailed review has been conducted to highlight different related aspects to biodiesel industry. These aspects include, biodiesel feedstocks, extraction and production methods, properties and qualities of biodiesel, problems and potential solutions of using vegetable oil, advantages and disadvantages of biodiesel, the economical viability and finally the future of biodiesel. The literature reviewed was selective and critical. Highly rated journals in scientific indexes were the preferred choice, although other non-indexed publications, such as Scientific Research and Essays or some internal reports from highly reputed organizations such as International Energy Agency (IEA), Energy Information Administration (EIA) and British Petroleum (BP) have also been cited. Based on the overview presented, it is clear that the search for beneficial biodiesel sources should focus on feedstocks that do not compete with food crops, do not lead to land-clearing and provide greenhouse-gas reductions. These feedstocks include non-edible oils such as Jatropha curcas and Calophyllum inophyllum , and more recently microalgae and genetically engineered plants such as poplar and switchgrass have emerged to be very promising feedstocks for biodiesel production. It has been found that feedstock alone represents more than 75% of the overall biodiesel production cost. Therefore, selecting the best feedstock is vital to ensure low production cost. It has also been found that the continuity in transesterification process is another choice to minimize the production cost. Biodiesel is currently not economically feasible, and more research and technological development are needed. Thus supporting policies are important to promote biodiesel research and make their prices competitive with other conventional sources of energy. Currently, biodiesel can be more effective if used as a complement to other energy sources.

A comprehensive review on biodiesel as an alternative energy resource and its characteristics

World energy demand is expected to increase due to the expanding urbanization, better living standards and increasing population. At a time when society is becoming increasingly aware of the declining reserves of fossil fuels beside the environmental concerns, it has become apparent that biodiesel is destined to make a substantial contribution to the future energy demands of the domestic and industrial economies. There are different potential feedstocks for biodiesel production. Non-edible vegetable oils which are known as the second generation feedstocks can be considered as promising substitutions for traditional edible food crops for the production of biodiesel. The use of non-edible plant oils is very significant because of the tremendous demand for edible oils as food source. Moreover, edible oils’ feedstock costs are far expensive to be used as fuel. Therefore, production of biodiesel from non-edible oils is an effective way to overcome all the associated problems with edible oils. However, the potential of converting non-edible oil into biodiesel must be well examined. This is because physical and chemical properties of biodiesel produced from any feedstock must comply with the limits of ASTM and DIN EN specifications for biodiesel fuels. This paper introduces non-edible vegetable oils to be used as biodiesel feedstocks. Several aspects related to these feedstocks have been reviewed from various recent publications. These aspects include overview of non-edible oil resources, advantages of non-edible oils, problems in exploitation of non-edible oils, fatty acid composition profiles (FAC) of various non-edible oils, oil extraction techniques, technologies of biodiesel production from non-edible oils, biodiesel standards and characterization, properties and characteristic of non-edible biodiesel and engine performance and emission production. As a conclusion, it has been found that there is a huge chance to produce biodiesel from non-edible oil sources and therefore it can boost the future production of biodiesel.

Non-edible vegetable oils: A critical evaluation of oil extraction, fatty acid compositions, biodiesel production, characteristics, engine performance and emissions production

From a Novel

Annual Energy Outlook 2008 With Projections to 2030

The rapid depletion of conventional fossil fuels and day-by-day growth of environmental pollution due to use of extensive use of fossil fuels have raised concerns over the use of the fossil fuels; and thus search for alternate renewable and sustainable sources for fuels has started in the last few decades. In this context biomass derived fuels seems to be the promising path; and various routes are available for the biomass processing such as pyrolysis, transesterification, hydrothermal liquefaction, steam reforming, etc.; and the hydrothermal liquefaction (HTL) of wet biomass seems to be the promising route. Therefore, this article briefly enlightened a few concepts of HTL such as the elemental composition of bio-crude obtained by HTL, different types of feedstock adopted for HTL, mechanism of HTL processes, possible process flow diagrams for HTL of both wet and dry biomass and energy efficiency of the process. In addition, this article also enlisted possible future research scope for concerned researchers and a few of them are setting up HTL plant suitable for both wet and dry biomass feedstock; analysing influence of parameters such as temperature, pressure, residence time, catalytic effects, etc.; deriving optimized pathways for better conversion; and development of theoretical models representing the process to the best possible accuracy depending on nature of feedstock.

A review on hydrothermal liquefaction of biomass

\n Hydrotreating process is an alternate approach for producing diesel hydrocarbons from the biomass-based oils. In the present study, used cooking oil was selected for the hydrotreating process due to its high abundance. A batch reactor was used for carrying out the experiments. To increase the reaction rate a manganese, cerium promoted ruthenium-based catalyst supported on Al2O3 was used. The design of experiments was used for optimizing the process parameters. The Taguchi method was selected as it reduces the number of experiments which saves time and money. The study was aimed at increasing the conversion percentage and diesel selectivity and reducing the naphtha selectivity. Since multi-objective optimization was required, fuzzy logic was incorporated which utilizes the human thought logic. The analysis of variance shows that the reaction temperature and reaction pressure significantly affect the output parameters. Higher temperature leads to cracking of the oil resulting in the formation of large amount of lower carbon chains. Moreover, high hydrogen pressure results in increase in the hydrogenation process, thereby increasing the diesel selectivity. The optimized parameters obtained from the study were 360 °C reaction temperature, 40-bar initial reaction pressure, and 200-min reaction time. Confirmation experiment was carried out using these parameters, and the conversion efficiency and diesel selectivity was 89.7% and 88.2%, respectively. The study shows that the combination of Taguchi and fuzzy logic is an effective method for optimizing the process parameters of the hydrotreating process.

Optimization of the Process Parameters for Hydrotreating Used Cooking Oil by the Taguchi Method and Fuzzy Logic

Copper selenide (Cu1.8Se) and silver selenide (Ag2Se) have garnered unprecedented attention as efficient absorber materials for cost-effective and sustainable solar cells. Phase pure preparation of these exotic materials in a nano-regime is highly desirable. This account outlines a simple and easily scalable pathway to Cu1.8Se and Ag2Se nanocrystals using novel complexes [Cu{2-SeC5H2(Me-4,6)2N}]4 (1), [Ag{2-SeC5H2(Me-4,6)2N}]6 (2) and [Ag{2-SeC5H3(Me-5)N}]6·2C6H5CH3 (3·2C6H5CH3) as single source molecular precursors (SSPs). Structural studies revealed that the Cu and Ag complexes crystallize into tetrameric and hexameric forms, respectively. This observed structural diversity in the complexes has been rationalized via DFT calculations and attributed to metal-metal bond endorsed energetics. The thermolysis at relatively lower temperature in oleylamine of complex 1 afforded cubic berzelianite Cu1.8Se and complexes 2 and 3 produced orthorhombic naumannite Ag2Se nanocrystals. The low temperature synthesis of these nanocrystals seems to be driven by the observed preformed Cu4Se4 and Ag6Se6 core in the complexes which have close resemblance with the bulk structure of the final materials (Cu1.8Se and Ag2Se). The crystal structure, phase purity, morphology, elemental composition and band gap of these nanocrystals were determined from pXRD, electron microscopy (SEM and TEM), EDS and DRS-UV, respectively. The band gap of these nanocrystals lies in the range suitable for solar cell applications. Finally, these nanocrystal-based prototype photo-electrochemical cells exhibit high photoresponsivity and stability under alternating light and dark conditions.

Facile one pot synthesis of highly photoresponsive coinage metal selenides (Cu1.8Se and Ag2Se) achieved through novel Cu and Ag pyridylselenolates as molecular precursors.

The exponential decay of crude oil and environmental degradation forced researchers to investigate alternative sustainable fuels. One of the promising alternatives to petroleum oil is orange peel o...

Naveen Kumar

Papers

Optimization of the Process Parameters for Hydrotreating Used Cooking Oil by the Taguchi Method and Fuzzy Logic

Facile one pot synthesis of highly photoresponsive coinage metal selenides (Cu1.8Se and Ag2Se) achieved through novel Cu and Ag pyridylselenolates as molecular precursors.

Experimental investigation and artificial neural network modeling of performance and emission of a CI engine using orange peel oil- diesel blends

Waste glycerol derived bio-propanol as a potential extender fuel for compressed ignition engine

Optimization Analysis of Injection Angle and Injector Nozzle of an Advanced Compressed Air Engine Kit