Biodiesel, The Catalysts For Production
The process of homemade biodiesel production is similar to
making soap. Vegetable oils and animal fats are triglycerides,
containing glycerin. To turn vegetable oil into biodiesel fuel
you must first eliminate the glycerin. When fat or oil is
separated from glycerin it is considered to be 'esterfied'.
During both homemade and professional biodiesel production,
alcohol (either methanol or ethanol) is added to displace the
glycerin so that it becomes a waste product. The chemical
reaction for this process is triggered by the addition of lye.
When you purchase Methanol you might notice that it is also
marketed under a lot of different names. Among them are alcohol,
wood alcohol, wood naphtha, wood spirits, methyl hydrate (or
'stove fuel'), carbinol, colonial spirits, Columbian spirits,
Manhattan spirits, methylol, methyl hydroxide, hydroxymethane,
monohydroxymethane and pyroxylic spirit. The bottom line is that
all of these nicknames and brands describe one product -
methanol.
Be careful when buying something called methylcarbinol as this
name can be used to describe both methanol and ethanol. Check
the ingredients to make sure that it is methanol you are buying
and not ethanol. Ethanol is just simply harder to work with when
it comes to creating homemade biodiesel.
Another mistake would also be to substitute Methylated spirits
(denatured alcohol) or isopropyl alcohol (rubbing alcohol) as
neither succeeds in creating biodiesel fuel. You can also buy
large amounts of methanol from bulk liquid fuels distributors
who supply to biodiesel production.
It is lye that changes the glycerin into biodiesel fuel (or the
fat to soap in the soap making process. The lye catalyst can be
either sodium hydroxide (caustic soda, NaOH) or potassium
hydroxide (KOH). Sodium hydroxide is often easier to obtain and
it's cheaper to use.
If you use potassium hydroxide, the process is the same, but you
need to use 1.4 times as much. You can get both NaOH and KOH
from craft stores, soap makers' suppliers and from chemical
suppliers. Other chemicals that are necessary for biodiesel
production, such as isopropyl alcohol (isopropanol) for
titration, are available from drug stores and chemical suppliers.
Of all of the chemicals used in biodiesel production, the lye is
the most dangerous. Don't get it on your skin or in your eyes,
don't breathe any fumes, keep lye away from food, and keep it
away from children and pets. Lye also reacts with aluminum, tin
and zinc so don't use any of these metals as a vessel or
container for holding your biodiesel.
By the end of the biodiesel production process the glycerin will
be sitting at the bottom of a container in two floating layers.
The bottom glycerin layer will clearly separated from the
biodiesel. The biodiesel at the top can then be removed or
siphoned off and used neat in a diesel car or diesel engineer
blended with petroleum-based diesel fuel.