Biofuel

Contribution of N2O to the greenhouse gas balance of first‐generation biofuels

by Adam Posthuma

The contribution of N2O to the greenhouse gas balance of first‐generation biofuels

by Adam Posthuma

Agricultural Research for Development in the Tropics: Caught between Energy Demands and Food Needs

by Folkard Asch

Asch, F., Huelsebusch, Chr., 2009.
Agricultural research for the Tropics: caught between energy demands and food needs. Journal of Agriculture and Rural Development in the Tropics and Subtropics 110 (1), 75–91

The use of plant biomass for fuel is almost as old as mankind. However, a continuously growing population and the... more The use of plant biomass for fuel is almost as old as mankind. However, a continuously growing population and the increasingly rapid exploitation of both fossil fuels and natural resources such as soil, water and biodiversity, have stimulated a debate of how to balance the needs and demands for food, feed, non-food raw materials and most recently energy in agricultural systems. Against the background of the current population growth, mankind faces the problem that the global system is closed and the available resources are finite. Energy is the only resource constantly supplied to the system from outside. All energy resources available on earth are in one way or the other transformations
of one of the four following: a) solar energy - which can be exploited directly, is transformed into biomass by photosynthesis, and drives the global wind and water cyle, b) tidal force owing to gravitational pull between earth and moon, c) the earth’s internal heat exploited as geothermic energy and d) nuclear energy. Of these, solar, tidal and geothermic energy are energy sources, which are not finite in time periods humans can still grasp. Based on data on fossil fuel reserves and consumption figures...

Biofuel Plant Simulation (presentation overview) - SARK7

by Scott Mongeau

Produced as independent research for SARK7 - presented at Palisade Europe 2010 Risk Management conference in London

Bioethanol, valuation, risk management, productivity,
simulation, techno-economic analysis Bioethanol, valuation, risk management, productivity,
simulation, techno-economic analysis

Genetic associations, variability and diversity in seed characters, growth, reproductive phenology and yield in Jatropha curcas (L.) accessions

by Arun Shanker

Stability of biodiesel and its blends: a review

by Siddharth Jain

Biodiesel consists of long chain fatty acid esters derived from feed stocks such as vegetable oils, animal fats and... more Biodiesel consists of long chain fatty acid esters derived from feed stocks such as vegetable oils, animal fats and used frying oil, etc. which may contain more or less unsaturated fatty acids which are prone to oxidation accelerated by exposure to air during storage and at high temperature may yield polymerized compounds. Auto oxidation of biodiesel can cause degradation of fuel quality by affecting the stability parameters. Biodiesel stability includes oxidation, storage and thermal stability. Oxidation instability can led to the formation of oxidation products like aldehydes, alcohols, shorter chain carboxylic acids, insolubles, gum and sediment in the biodiesel. Thermal instability is concerned with the increased rate of oxidation at higher temperature which in turn, increases the weight of oil and fat due to the formation of insolubles. Storage stability is the ability of liquid fuel to resist change in its physical and chemical characteristics brought about by its interaction with its environment and may be affected by interaction with contaminants, light, factors causing sediment formation, changes in color and other changes that reduce the clarity of the fuel. These fuel instabilities give rise to formation of undesirable substances in biodiesel and its blends beyond acceptable quantities as per specifications and when such fuel is used in engine, it impairs the engine performance due to fuel filter plugging, injector fouling, deposit formation in engine combustion chamber and various components of the fuel system.
The present review attempts to cover the different types of fuel stabilities, mechanism of occurrence and correlations/equations developed to investigate the impact of various stability parameters on the stability of the fuel. A review of the use of different types of natural and synthetic antioxidants has also been presented which indicates that natural antioxidants, being very sensitive to biodiesel production techniques and the distillation processes have varying impacts on fuel stability and available literature is very much scarce. The work on the use of synthetic antioxidants on the stability of biodiesel (both distilled and undistilled) from various resources has indicated that out of various 8 synthetic antioxidants studied so far only 3 antioxidants have been found to increase the fuel stability significantly. However, effectiveness of these antioxidants is in the order of TBHQ > PY > PG.

Jatropha Curcas Oil: A Future Source of Biodiesel

by Siddharth Jain

Presented in International Symposium on Renewable Feedstock for Biofuel and Bio-based Products held at Austin, USA from 10- 13 Aug 2010

Acid base catalyzed transesterification kinetics of waste cooking oil

by Siddharth Jain

The present study reports the results of kinetics study of acid base catalyzed two step transesterification process of... more The present study reports the results of kinetics study of acid base catalyzed two step transesterification process of waste cooking oil, carried out at pre-determined optimum temperature of 65 °C and 50 °C for esterification and transesterification process respectively under the optimum condition of methanol to oil ratio of 3:7 (v/v), catalyst concentration 1%(w/w) for H2SO4 and NaOH and 400 rpm of stirring. The optimum temperature was determined based on the yield of ME at different temperature. Simply, the optimum concentration of H2SO4 and NaOH was determined with respect to ME Yield. The results indicated that both esterification and transesterification reaction are of first order rate reaction with reaction rate constant of 0.0031 min− 1 and 0.0078 min− 1 respectively showing that the former is a slower process than the later. The maximum yield of 21.50% of ME during esterification and 90.6% from transesterification of pretreated WCO has been obtained. This is the first study of its kind which deals with simplified kinetics of two step acid–base catalyzed transesterification process carried under the above optimum conditions and took about 6 h for complete conversion of TG to ME with least amount of activation energy. Also various parameters related to experiments are optimized with respect to ME yield.

Prospects of biodiesel from Jatropha in India: A review

by Siddharth Jain

The increasing industrialization and modernization of the world has to a steep rise for the demand of petroleum... more The increasing industrialization and modernization of the world has to a steep rise for the demand of petroleum products. Economic development in developing countries has led to huge increase in the energy demand. In India, the energy demand is increasing at a rate of 6.5% per annum. The crude oil demand of the country is met by import of about 80%. Thus the energy security has become a key issue for the nation as a whole. Petroleum-based fuels are limited. The finite reserves are highly concentrated in certain regions of the world. Therefore, those countries not having these reserves are facing foreign exchange crises, mainly due to the import of crude oil. Hence it is necessary to look forward for alternative fuels, which can be produced from feedstocks available within the country.
Biodiesel, an ecofriendly and renewable fuel substitute for diesel has been getting the attention of researchers/scientists of all over the world. The R & D has indicated that up to B20, there is no need of modification and little work is available related to suitability and sustainability of biodiesel production from Jatropha as non-edible oil sources. In addition, the use of vegetable oil as fuel is less polluting than petroleum fuels. The basic problem with biodiesel is that it is more prone to oxidation resulting in the increase in viscosity of biodiesel with respect to time which in turn leads to piston sticking, gum formation and fuel atomization problems.
The report is an attempt to present the prevailing fossil fuel scenario with respect to petroleum diesel, fuel properties of biodiesel resources for biodiesel production, processes for its production, purification, etc. Lastly, an introduction of stability of biodiesel will also be presented.