Biodiesel Conversion to Relieve our Addiction to Foreign Oil: A Review and Analysis of Relevant Literature
Abstract
This literature review is meant to sort and organize my research thus far into the expansive biodiesel and biofuel advancements since the discovery of transesterification. The world petroleum consumption has grown exponentially throughout the 20th century, drying up many of our once rich oil reserves. As our non-renewable fuels dry up and our atmosphere fills with their exhaust, we must look to renewable and clean bio-fuels such as biodiesel to supplement our energy use. The sources referenced and analyzed in this review aid to understand the background of biodiesel in our society since its first successful use in 1892, and the series of discoveries leading to our expansive knowledge of the production, application, and environmental consequences of biodiesel.
What is Biodiesel?
Today, biodiesel is a fuel used in compression ignition engines which is derived from feedstock and economically non-competitive oils like soybean oil or animal fats like lard or algae biomass composed primarily of lipids and triglycerides. This fuel can be mixed in proportion to petroleum in order to supplement standard diesel. (Wikipedia; Biodiesel) “Biodiesel is the product obtained through the transesterification of animal fats or vegetable oil, yielding fatty acid methyl esters or FAME” (Kemp; 107) The process of transesterification is where the fat molecule in the form of a glycerin molecule bonded to 3 fatty acids (hydrocarbon chains) is torn apart by the addition of methanol alongside an alkaline catalyst such as sodium or potassium hydroxide, resulting in the transfer of each fatty acid to a methanol molecule and leaving the glycerin byproduct which is then filtered out. The chemical properties such as viscosity and free fatty acids (FFAs) of the resulting liquid are dependent on the type of oil or fat used. (Kemp; 108-9)
Biodiesel vs. Conventional Diesel
Petroleum diesel is a derivative of crude oil, which has been refined through the careful distillation of the oil in order to separate the different hydrocarbon molecules by taking advantage of their varying boiling points. (Kemp; 59) The end result of the refining and treatment of the crude oil are saturated and aromatic hydrocarbons. (Wikipedia; Diesel fuel) Compared to this, biodiesel is a much cleaner fuel, containing less sulfur oxides and sulfates while producing fewer unburned hydrocarbons, carbon monoxide and particulate matter. The improved emissions can be credited to the inherently higher purity of biodiesel. (Kemp; ?? In addition, the U.S. Departments of Agriculture and Energy have conducted studies on the lifecycle of biodiesel, and how its emissions affect our atmosphere. They found that while biodiesel is slightly less energy efficient when produced, the CO2 emissions, particulate matter, and carbon monoxide emissions are all lowered. (Sheehan; 33)
History of Biodiesel in an Internal Combustion Engine
Biodiesel was the original fuel intended to be used in diesel engines, as Rudolf Diesel, the inventor of the diesel engine had originally used peanut oil to demonstrate his newly invented engine at the 1900 Paris World Fair (Wikipedia; Rudolf Diesel) The diesel engine was developed throughout the 20th century as a replacement to the steam engine, and began to be used in ships, submarines, locomotives, trucks, and heavy machinery. (Wikipedia; Rudolf Diesel) As the diesel engine was revised, biodiesel underwent immense advancements
Biodiesel Developments
Biodiesel has undergone 3 generations since the discovery of transesterification in 1853, when two chemists, E. Duffy and J. Patrick, experimented with the process while trying to make soap. (History of Biofuels) The 1st generation was based upon food-stocks, or human consumed food oils. This generation was not useful because it competed with food markets to produce biodiesel, which made the cost of biodiesel unfathomable. Second generation biodiesel was generated from feed-stocks, which is raw natural biomass which is processed specifically for use in biodiesel. These feed-stocks did not compete with markets to the extent that food-stocks do, but their competition at all still made biodiesel inconvenient at higher production rates. Lastly, third generation biodiesel depends on algae biomass with high triglyceride content such as Chlorella. Third generation biodiesel has recently been developed, and promises a green biofuel which does not compete with any industries for their feed-stocks, making it affordable as well.
Environmental Effects of Biodiesel Emission
The improved emissions of biodiesel can be credited to the inherently higher purity of biodiesel compared to petroleum diesel. (Wikipedia; Biodiesel) In addition, the U.S. Departments of Agriculture and Energy have conducted studies on the lifecycle of biodiesel, and how its emissions affect our atmosphere. They found that while biodiesel is slightly less energy efficient when produced, the CO2 emissions, particulate matter, and carbon monoxide emissions are all lowered. However, Biodiesel does cause a rise in NOx and Total Hydrocarbons (THC) emissions (Sheehan; 33), both of which can be minimized by advanced catalytic converters and Exhaust Gas Recirculation (EGR) valves (Gedeon; 16)
Abstract
This literature review is meant to sort and organize my research thus far into the expansive biodiesel and biofuel advancements since the discovery of transesterification. The world petroleum consumption has grown exponentially throughout the 20th century, drying up many of our once rich oil reserves. As our non-renewable fuels dry up and our atmosphere fills with their exhaust, we must look to renewable and clean bio-fuels such as biodiesel to supplement our energy use. The sources referenced and analyzed in this review aid to understand the background of biodiesel in our society since its first successful use in 1892, and the series of discoveries leading to our expansive knowledge of the production, application, and environmental consequences of biodiesel.
What is Biodiesel?
Today, biodiesel is a fuel used in compression ignition engines which is derived from feedstock and economically non-competitive oils like soybean oil or animal fats like lard or algae biomass composed primarily of lipids and triglycerides. This fuel can be mixed in proportion to petroleum in order to supplement standard diesel. (Wikipedia; Biodiesel) “Biodiesel is the product obtained through the transesterification of animal fats or vegetable oil, yielding fatty acid methyl esters or FAME” (Kemp; 107) The process of transesterification is where the fat molecule in the form of a glycerin molecule bonded to 3 fatty acids (hydrocarbon chains) is torn apart by the addition of methanol alongside an alkaline catalyst such as sodium or potassium hydroxide, resulting in the transfer of each fatty acid to a methanol molecule and leaving the glycerin byproduct which is then filtered out. The chemical properties such as viscosity and free fatty acids (FFAs) of the resulting liquid are dependent on the type of oil or fat used. (Kemp; 108-9)
Biodiesel vs. Conventional Diesel
Petroleum diesel is a derivative of crude oil, which has been refined through the careful distillation of the oil in order to separate the different hydrocarbon molecules by taking advantage of their varying boiling points. (Kemp; 59) The end result of the refining and treatment of the crude oil are saturated and aromatic hydrocarbons. (Wikipedia; Diesel fuel) Compared to this, biodiesel is a much cleaner fuel, containing less sulfur oxides and sulfates while producing fewer unburned hydrocarbons, carbon monoxide and particulate matter. The improved emissions can be credited to the inherently higher purity of biodiesel. (Kemp; ?? In addition, the U.S. Departments of Agriculture and Energy have conducted studies on the lifecycle of biodiesel, and how its emissions affect our atmosphere. They found that while biodiesel is slightly less energy efficient when produced, the CO2 emissions, particulate matter, and carbon monoxide emissions are all lowered. (Sheehan; 33)
History of Biodiesel in an Internal Combustion Engine
Biodiesel was the original fuel intended to be used in diesel engines, as Rudolf Diesel, the inventor of the diesel engine had originally used peanut oil to demonstrate his newly invented engine at the 1900 Paris World Fair (Wikipedia; Rudolf Diesel) The diesel engine was developed throughout the 20th century as a replacement to the steam engine, and began to be used in ships, submarines, locomotives, trucks, and heavy machinery. (Wikipedia; Rudolf Diesel) As the diesel engine was revised, biodiesel underwent immense advancements
Biodiesel Developments
Biodiesel has undergone 3 generations since the discovery of transesterification in 1853, when two chemists, E. Duffy and J. Patrick, experimented with the process while trying to make soap. (History of Biofuels) The 1st generation was based upon food-stocks, or human consumed food oils. This generation was not useful because it competed with food markets to produce biodiesel, which made the cost of biodiesel unfathomable. Second generation biodiesel was generated from feed-stocks, which is raw natural biomass which is processed specifically for use in biodiesel. These feed-stocks did not compete with markets to the extent that food-stocks do, but their competition at all still made biodiesel inconvenient at higher production rates. Lastly, third generation biodiesel depends on algae biomass with high triglyceride content such as Chlorella. Third generation biodiesel has recently been developed, and promises a green biofuel which does not compete with any industries for their feed-stocks, making it affordable as well.
Environmental Effects of Biodiesel Emission
The improved emissions of biodiesel can be credited to the inherently higher purity of biodiesel compared to petroleum diesel. (Wikipedia; Biodiesel) In addition, the U.S. Departments of Agriculture and Energy have conducted studies on the lifecycle of biodiesel, and how its emissions affect our atmosphere. They found that while biodiesel is slightly less energy efficient when produced, the CO2 emissions, particulate matter, and carbon monoxide emissions are all lowered. However, Biodiesel does cause a rise in NOx and Total Hydrocarbons (THC) emissions (Sheehan; 33), both of which can be minimized by advanced catalytic converters and Exhaust Gas Recirculation (EGR) valves (Gedeon; 16)