quote:

Originally posted by JohnTF:
as far as I have read comes in at least 2 levels , M1 lower grade , then Tech higher grade , mostly what the racers are using.

I think you have that backwards. "M1" is a part number designation for VP Racing Fuels pure methanol (99.95%). This is the stuff they use in $100,000 racing engines. That's what I had been using for biodiesel. The VP dealer that I get it from recently started selling a "tech grade" methanol that is cheaper and less pure. The "tech grade" methanol isn't a VP product. I'm going to start using that the next time I buy.

Ken

quote:

it stops producing at about 200 degrees. Quality is between 95 and 98% pure.

Wow...that's pretty cool with that short of a reflux area.

Oh-Wait! You probably don't do any prewash, do you? I couldn't get away with such a short reflux region and going to so high a temp...I do the 5% prewash, so I need to avoid water.

I do 40 gallon batches so I run my still every other batch, I get about 9 gallons of glycerin per batch. By the way had a great time at your place Andrew and hope to meet up with you again some day.

Ryan you are correct I do not use the prewash for that very reason. It doesn't save me much time to do a prewash and it makes it more trouble to recover the Methanol and recovery is more important than time saved in the process of washing.

Blair

quote:

Originally posted by Andrew Morris:
Bpine,

quote:

I use 22% in my process and when I fill my 15 gallon recovery still with about 12 gallons of Glycerin I get back 3 1/2 to 4 gallons of methanol.

how is it going?

The 12 gallons, is that 2 batches? What size batch?

I did a rough calc. and it sounds like you are getting under 15% total use. That is excellent!

I use a 40 gal. appleseed with vacume recovery. Typical batch:

100 liters wvo titrate 1.5 naoh
22 liters meth
base \ base with 5% prewash
distill everything together at 145 degrees f. and 27 in. hg. 3 to 4 hours
recover about 10 liters 85 to 90% methanol. ( tested with homade hydrometer)
3/27 tested before and after recovery, no evidence of reaction reversal

I experimented with recovery BEFORE prewash:
175 degrees @ 27 in. hg 4 hours
recovered 90% of original methanol (very high purity)
When I added 5% prewash I got lots of peanut butter and about 50% yield of biodeisel.
The peanut butter seemed to be pure soap. The was no liquid glycerin.

I believe that if I would have stopped recovery sooner the batch may have been successfull.

I have just recieved a store bought hydrometer and plan to experiment further.

If anyone has experience along these lines I welcome your responce.

quote:

Originally posted by BeeRanch:
. . . no evidence of reaction reversal. . . .

The primary compounds created in a reverse reaction will not show up in the 3/27 test.

In the normal biodiesel reaction the starting compound is tri-glycerides (TG). The TG converts to di-glycerides (DG). The DG converts to mono-glycerides (MG). The MG converts to biodiesel (BD).

In reality, BD is only produced from MG.

The TG becomes fully converted at a point in time in the reaction when the overall reaction is only about 95% complete. So, even though there is no more TG to be converted, the reaction must proceed until more of the DG and MG are converted. (This assumes you are trying to meet the ASTM spec for BD.)

The 3/27 test is only an indicater test and works because the BD, MG, and DG are all soluble in methanol. Only TG is insoluble, so it is the only compound that drops out.

A reverse reaction occurs when BD is converted, first, to MG. The MG then converts to DG. Only the DG can convert to TG.

Therefore, the first compounds formed by a reverse reaction will not show up in the 3/27 test.

Having said the above, the effects of a reverse reaction may be acceptable to you. If you produce BD for your own use, keep it dry, do not use the BD in the newer (2007) diesel engines, and use it timely, then I don't think a reverse reaction will cause you any real problems.

Producer, thanks for your reply.

I have a couple of questions:

Is there a test that can be done by homebrewers to show evidence of a reverse reaction?

Has anyone successfully produced vegtable oil from glycerin and biodeisel?

quote:

Originally posted by BeeRanch:
. . . Is there a test that can be done by homebrewers to show evidence of a reverse reaction?

Methanol is "produced" as by-product of the reverse reaction.

If you recover methanol and can accurately measure its specific gravity, then yes, there is at least one test that will show evidence of a reverse reaction.

Check your recovered methanol for specific gravity. If the specific gravity of the methanol approaches the specific gravity of pure methanol, then that is evidence that a reverse reaction may be occurring.



As to your second question "Has anyone successfully produced vegtable oil from glycerin and biodiesel?" I don't know, but I doubt it.

The reaction to produce "pure" vegetable oil is the same transesterification reaction employed to produce BD, so it is reversible. As you approach 100% pure vegetable oil, then MG, DG, and BD would have a greater influence on the results. You might have to continuously remove excess methanol and provide a large amount of excess glycerol to drive the reaction towards vegetable (TG) oil.

Keep in mind that I am not a chemist. I just play one around biodiesel. This is very important to remember when reading the previous two paragraphs.

I'm a little confused. I can't find a straight answer on how much methanol we should be able to recover on average from the biodiesel with a 5% prewash.
I made 246.35 liters yesterday and recovered 5 liters of Methanol from the biodiesel after draining off the glycerine. I had the temp up to 90c or 194f and noticed the methanol only distilled only while the heating element was on. My original methanol input was 22% or 54.197 liters / 14.3 gallons of methanol.

Any insight from you guys would be appreciated.

Rico I used to have a thermostat as well and every time it would cycle the methanol stopped so I just let the heat go for a set length of time now and it works well. Once again I get 3 1/2 to 4 gallons of 95 to 98% methanol out of approx 12 gallons of glycerin.

Sorry to burst the thread, but if I cap the glycerin in a cubee will I be able to recover methanol months down the road? I would consider stocking some and giving it away if so. pm me if any interest located in northern illinois

quote:

if I cap the glycerin in a cubee will I be able to recover methanol months down the road?

I hope so...as I have exactly this and some of my raw glycerin cubees are a year old waiting for me to recover them. Seems to be working so far.

Greetings,
I just finished up recovering meth from some two year old cubies of raw glycerin. The plastic on some of the cubies was breaking down and leaking.
YUCK! I still(HA HA)recovered my usual meth - 13 gals. from 45 gals raw glycerin.
Terrybear

quote:

Originally posted by AwesomeNet:
HDJ80,

Could you explain your setup as well? I built a separate distillation system. My first run was with 90 liters of biproduct and I had 16 liters of methanol when I got foam. The foam messed up my purity calculations since glycerine has a higher density than water. I estimate that the purity was in the mid 90's when I got about 1/4 liter of glycerine in my methanol cubie.

Steve

Sorry Steve that I was so late to reply but I don't visit too often these days...
I use 2 Hot water Cylinders one to make the bio then after settling the glycerol is transferred (by gravity) to the second, then with the aid of air pumps and heat I bubble the bio in the processor and the glycerol in the second HW heater distilling from both the bio and glycerol at the same time in separate vessels. Works extremely well and uses no pumps pipes, hoses etc which could fail with the heat causing a mess or catastrophic results.
I have been doing this for nearly 2 years and recover 33% methanol at 100% purity… Also the air washing of the bio after this takes only 24 hours to finish the bio to make it ready for using.
Passes 3/27 everytime..

Bio Setup