David G. B. Boocock, professor of chemical engineering at U of T, has found a way to use mad cow carcasses to create diesel fuel. He explained his findings in a lecture last week
The fuel is called “biodiesel”-diesel made from organic fats and oils. This fuel is actually very common in Europe where approximately 50 per cent of cars have diesel engines. Originally, biodiesel was made from vegetable oils, making it a renewable resource. Rapeseed oil is the most common type in Europe, but any vegetable oil can work.
The fuel is biodegradable. “Bugs love the stuff!” Boocock said, and therefore oil spills are not a problem as scientists can use microbes to break down the oil. It has no sulfur and therefore does not emit sulfuric acid, it mixes in all proportions with normal diesel fuel, and it runs in a normal diesel engine.
So where does the mad cow come in? Since the fuel is contained in crops, and animals like cows eat the crops, the fuel becomes a part of their body in the form of fat.
Normally after a carcass is used by a restaurant the fat is taken away to a renderer where it is made into something useful, like biodiesel. As a result of the spread of Bovine Spongiform Encephalopathy (BSE, or mad cow disease) many nations, including Canada, have an excess of cow carcasses.
Boocock said the only thing stopping the conversion of these carcasses into biodiesel is a lack of incentives: chemists need either government regulation to mandate a conversion of carcasses to fuel or for the diesel fuel market to demand biodiesel.
What is stopping the world from switching to diesel engines and more environmentally friendly biodiesel fuel? Diesel engines are more expensive than regular gasoline engines. However in Europe fuel is expensive, and diesel engines with cheaper fuel are actually less costly in the long term.
In North America trucks and some trains are the main guzzlers of diesel fuel, as they are the only vehicles who need the more powerful engine. But even in this limited market, there would not be enough biodiesel fuel to supply them all. Estimates are that at most Canada could supply 20 per cent of its vehicles with pure biodiesel fuel.
The solution, however, is to do more with the biodiesel fuel we do have. Biodiesel fuel mixes with normal diesel fuel, and biodiesel does not contain sulfur. Since it can thicken the diesel as sulfur normally does, fuel companies can remove sulfur from the fuel. This new fuel will not emit sulfurous gas and will not contribute to environmental degradation.
The government has mandated that sulfur levels in diesel fuel must come down from their current level of 0.5 per cent to a negligible level by 2006. Many American states however, are more aggressive, already mandating all diesel fuel to have a certain percentage biodiesel in it. Scientists label the mixed fuel for its percentage biodiesel. For example, B-10 means 10 per cent of the fuel is biodiesel. The higher the B-number, the greater its contribution against global warming. Normal levels are between B-5 and B-15.
We could not use 100 per cent pure biodiesel, especially in Canada, because it binds together and becomes useless at low temperatures. Boocock says as long as we use B-15 or less we will not encounter any solidifying problem.
Boocock has researched how to mix together the substances that produce biodiesel fuel. Before the reaction the two liquids look like oil and water stacked on top of one another-they do not mix together. He demonstrated his new method of mixing the two together. He adds a catalyst, in this case lye, and a fourth substance to increase the surface area of the mixture and give the molecules space to react. He demonstrated to the audience the old method too, which is still in use in Europe, of just mixing the two substances with the lye and shaking it furiously like a bottle of salad dressing. His method produced better and more complete results.
