Rudolf Diesel invented the diesel engine in the 1890s. From the beginning, this engine could run on a variety of fuels, including vegetable oil. In 1900, one of the new diesel engines featured at the Paris Exposition was powered by peanut oil. However, because cheap petroleum fuels were easily available, few people were interested in alternatives (Pahl, 2005, pp. 18-22).
As early as the 1930s, there was interest in splitting the fatty acids from the glycerin in …
Biodiesel that leaves the production plant in good condition can become unacceptable during distribution without proper care and attention. Biodiesel can degrade due to oxidation, contact with water, and/or microbial activity.
In general, biodiesel will degrade more quickly than petro-diesel. In one sense, this is a good thing: a biodiesel spill will biodegrade quickly and not cause as many environmental problems as a petro-diesel spill. Nevertheless, both fuels will eventually degrade, and the same good housekeeping practices that apply …
Introduction to Saponification
Saponification is a chemical reaction that involves the production of a metal salt or soap. The reaction involves the attack on a methyl ester, free fatty acid, triglyceride, or other glyceride by a hydroxide ion, –OH.
The hydroxide ion implies the presence of water in the system. If water could be eliminated, then there would be no soap formation. However, this is a practical impossibility. There is always some water present, and there will always be …
Three general types of reactors are used for biodiesel production: batch reactors, semi-continuous-flow reactors, and continuous-flow reactors.
The batch process is inexpensive, requiring much less initial capital and infrastructure investment. It is flexible and allows the user to accommodate variations in feedstock type, composition, and quantity. The major drawbacks of the batch process include low productivity, larger variation in product quality, and more intensive labor and energy requirements.
The semi-continuous process is similar to the batch process except that …
The methoxide ion, –OCH3, is the active catalyst for the production of methyl esters. It is this chemical unit that attacks the triglyceride molecules and produces the methyl esters. It is regenerated at the end of each reaction step when a hydrogen ion is stripped from a nearby methanol molecule.
If ethanol is being used, then the corresponding catalyst is called ethoxide, –OCH2CH3.
Most small producers create the methoxide ions needed for …
Biodiesel is a diesel fuel substitute made from a variety of oils, fats, and greases.
Biodiesel, a diesel fuel substitute that can be made from a variety of oils, fats, and greases, is of interest to farmers for a number of reasons: It can provide an additional market for vegetable oils and animal fats; it can allow farmers to grow the fuel they need for farm machinery; and it can decrease U.S. dependence on imported oil since fuel feedstocks …