The Imisides processing method

[dgs]

A while ago I posted a thread about using quick lime to dry methoxide. Recently there has been some discussion about this method on the Australian Biofuels Forum. As a response to this the architect of the method Mark Imisides has made a few posts and given a link to his own site.

For us non chemists the first part of the link is taken up with technical aspects so it may be best to go straight to the method itself. As Mark says it is not necessary to understand the chemistry to try this method. As there has been some recent discussion on here about ambient processing I thought it may be of interest.

http://drchemical.com.au/biodiesel

Here is an extract from Marks Post on the Biofuels Forum.

Re: The Imsides method
Please note that I have now set up a link on my website devoted to this method. http://drchemical.com.au/biodiesel Note to moderators - this is not a commercial site, and all the information is freely available.  at last it seems that people are starting to wake up to the fact that heating your biodiesel and doing titrations is not necessary.


The first section lays out the chemistry of the process, and the second takes you through the method. You do not have to understand the chemistry of the process to follow the method.


My website lays out the process and the chemistry in detail, so all these questions will be answered there. For those of you that are students of Chemistry I can help you understand some of the finer details if you wish, but for the rest of you, just follow the process as laid out and it'll work. The beauty of this method is that all the quantities are bulk quantities, and there are no fiddly titrations or exact weighing required.

Also there is a place at the bottom where you can ask questions or make comments, and I will respond accordingly.

[DavidShinn]

Hi Dave,

I think one of the conclusions we came to last year after the testing was that the method might have benefits for those who are using methanol that is wet to start with as the quicklime reacts with any water as well as removing 'some' byproduct water from the koh/methanol reaction.

Do you feel the urge for more testing coming on?

Kind regards

David.

[dgs]

Hi David, one of the problems I had was to try and get the settled methoxide out of the cubie without any of the CaO fines. Ideally a cubie with a tap would be good but could only be used once as the Calcium Hydroxide sets really hard in the bottom.

In his instructions Mark doesn't mention this, presumably he can only use his 200 litre methoxide mixer only once for this reason.

The other point I've realised is he mentions 13kgs of KOH for 870 litres of WVO which is a massive amount, almost 15gms/litre.  As he doesn't know any acid value he just wants to ensure there is enough catalyst to achieve 100% conversion and as the methoxide contains no or little water then very little soap will be formed by saponification.

[Julian]

Makes interesting reading, if only I understood the chemistry!

I did try using quicklime and cement powder to dry recovered methanol some years ago, but it didn't seem to work for me.  Most unscientific tests, but I never seemed to be able to improve the SG of the methanol ... most probably me doing things wrong again!

I'd question the comment regarding the 55°C minimum reaction temperature as, inspired by Dave, I've been reacting at ambient temperatures for some time with pleasing results.  I have to admit that Frankinpump raises the temperature of the bio, but the conversion is evident way below 55°C.

Also interesting was the comment about shear as the bio is pumped back into the IBC.  In comparison to the shear created in the pump (especially a Frankinpump which must be particularly inefficient given the energy available to raise the bio temperature) I'd have thought this was insignificant, but it may explain why we see conversion at low temperatures.

Some years ago I was involved in diesel emulsification tests and, in conjunction with one of the universities, the company developed and pump like devise to emulsify water and diesel.  I've always wondered if a similar device would be beneficial in bio production ... it would be quite easy to convert a centrifugal pump to do the job.