WFU Biofuels

Wake Forest students, faculty, staff and associates making and testing vegetable-oil based fuels.

Tuesday, October 25, 2005

What's coming out of that pipe?

I've been reading a lot of papers on testing and production of B100. I found a very good review article (Analytical Methods Used in the Production and Fuel Quality Assessment of Biodiesel, Transactions of the ASAE, Vol 44(2), 193-200). There are several methods used to monitor fuel quality; Gas, High Performance Liquid and Gel Permeation Chromatography. As well as spectroscopic methods; proton and carbon 13 NMR and Near IR. Other methods are viscometry, titrations and enzymatic reactions.
I was surprised to find that Near IR or Viscometry are the methods of choice for routine evaluation in production. Soy oil has a viscosity of 32.66 mm^2/s at 38C and Soy FAME has a value of 4.41 mm^2/s at 40C. This method is suitable for process-control purposes. So if you are producing B100 and the viscosity changes a lot then you go to GC analysis to figure out what’s wrong. A lot cheaper and faster.
I’ve also been reading about continuous reaction processes. I have many more questions than answers. I’d like to go and tour a B100 plant to see how the big boys do this. I have learned that without some technical advantage then only scale of economy will allow you to be competitive in the market place. Here’s an example of a company that has spun off from CARNEGIE MELLON UNIVERSITY. Full article here: (full article here: )

“Conventional biodiesel plants use batch processing, mixing together alcohol and liquid catalysts that are stirred and heated to produce a methylester from a pure plant oil or animal fat, along with the by-product, glycerine. The processing of pure oils prevents them from thickening too much in colder temperatures.
By contrast, Capital Technologies' equipment and process involves microwave heating, proprietary solid catalysts and continuous processing that can be expanded by adding production modules that the company is assembling at a South Side manufacturing facility, said Marc Portnoff, senior scientist at CMU's Center for Advanced Fuel Technology.
The CMU center developed the new process with financial sponsorship from Capital Technologies, which until recently was a research and development venture backed by investors, including Jackson and John Sununu, former New Hampshire governor and onetime chief of staff during the first Bush administration.
Among the advantages of the new technology are that it takes up less space, in part because of the microwave heating, and can be readily expanded, said Portnoff. He, along with the CMU center's director, David Purta, expects to leave his CMU post to join the new venture in several weeks.
In addition, because it uses solid rather than liquid catalysts, "Our cleaning process [to remove impurities from the biodiesel] is a lot easier," and the manufacturing facility can be much smaller, Portnoff said. Production rates also are double the rates for conventional processes, he added.”

I have found papers reporting FAME synthesis using microwaves and solid catalysis. The technical advantages are faster reaction times (less energy input) and little or no washing. That’s right, little or no washing!!! Now imagine a centrifuge at the end and you have a nice continuous process. So as we build a batch processor I’d like to see someone build a small bench-top continuous processor, sort of a proof of concept project.


At 10:46 AM, Blogger oilySOB said...

This is really cool!
Does liquid catalyst mean that we need to purchase from a different source that supplies liquid, or do we convert our catalyst to liquid somehow (melting?)?

I think you're right in that we need to either be bigger than others or more innovative than others to be more successful. (In the end, if another, larger producer does end up "eating our lunch", then I would still be happy that we could be producing fuel for ourselves and the university cheaply and responsibly.)

I think bean-o (AKA "The Shaman") is doing some great stuff here. I would love to see us successfully implement new, cutting-edge techniques to make our b100 more easily and cheaply. Great work!

At 1:50 PM, Blogger Asa Gray said...

I agree with the Oily SOB: this is neat stuff. Big Rig and I were talking about making a kinematic viscosimeter last week. I have an old mentor that is famous for making cool machines on the cheap. I'll give him a call. Does anyone have a physics (or chem) professor that likes challenges like this?


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