What Goes Into The Production of Biodiesel

Biodiesel production is the lipid transesterification process which is used to convert a base oil in to the desired esters (biodiesel).  Any fatty free acids in the base oil can either be converted into soap and then removed from the process or they can be further esterified in order to produce more biodiesel using an acidic catalyst.  One this process has been completed unlike normal vegetable oil, biodiesel has very similar combustion properties as that of petroleum diesel and in some cases is replacing it.

To produce biodiesel the following types of products can be used in the production process.

1. Virgin oil feedstock - Rapeseed and Soybean oils are the most commonly used of these feedstock oils.  With soybean oil being used to produce about 90% of the fuel stocks available.
2.  Waste vegetable oil - it is what it says.  Oil that has previously been used for cooking etc.
3.  Animal Fats - Such as tallow, lard, yellow grease, chicken fat and the by products from the production of Omega-3 fatty acids which comes from fish oil.
4.  Sewage - There is a company in New Zealand which has successfully developed a system for using sewage waste as a substrate for algae which can then be used to produce biodiesel.

At present the production methods that are used to produce biodiesel involve the dissolving of a catalyst such as sodium hydroxide in alcohol and then agitating this mixture with vegetable oil in a large vat for 2 hours.  The liquid is then allowed to sit for between 12 to 24 hours when a slow chemical reaction occurs that creates both biodiesel and glycerin (this by product is then separated away from the biodiesel). 

However a microreactor has been developed at OSU which eliminates the mixing, standing time for separation and potentially no need for a dissolved catalyst to be included in the production of biodiesel.  They are also looking at a looking at developing a method for coating the microchannels with a non-toxic mettallic catalyst which would eliminate the need for the chemical catalyst altogether and which will then make the production of biodiesel even simpler.

So as you can see the future for biodiesel production could be altered in such a way that the use of a dissolved catalyst and chemical catalyst will no longer be required.