help with first batch

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Oct 9, 2009 | 11:41 AM

72f2504x4390

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From: spokane WA

help with first batch

Did my first batch the other day and got about 4% unreacted with the methanol test.

Did my second batch last night and got about 2% unreacted.

So I have been doing more reading and I think my KOH base might be too low, getting conflicting #'s

The recipe I was following suggested 5.0 base + titration. The oil I am using titrates very low @ 2.0
25% methanol
This is a 4 gallon batch, with paint stir agitation processed for 60 minutes kept between 120-135F.

First batch I used 7.0/liter.

Second batch I used 8.0/liter.

So I have read more and find some other #'s for base using koh. I see 7.0 and 9.0/liter.

Looking for complete reaction, but not too much soap(read, easy wash)

Any advice appreciated.

Oct 9, 2009 | 12:52 PM

fabmandelux

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From: Paradise Found!

Quote:

Originally Posted by 72f2504x4390

5.0/ltr is way to low. Base for KOH at 100% is 7.8/ltr + titration.

The KOH that I get is 90%, so I use a base of 8.2/ltr + titration.

If your KOH is 90% you should have used 8.2 + 2 for a final figure of 10.2/ltr.

120 deg is to cold, and would require longer mix time.

Oct 9, 2009 | 01:21 PM

72f2504x4390

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From: spokane WA

I was trying to keep it between 130-140 but I need to watch it a little closer. It was up around 130 for most of the time, but I know it was down in the 120's at one point.

going to try another batch here in a bit. Not sure on the potency of my KOH, got it from braintan.com it doesn't specify the potency. Probably should figure on it being 90%

I will use your figures and see how it works out.

I am getting close to that figure with trial and error anyway.

Oct 10, 2009 | 12:31 AM

binuya

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From: Seattle

Don pretty much has it covered. I am curious as to how you are determining that amount of unreacted bio out of 3ml.

You may already know this, but if you don't, your 3/27 test needs to be held at 68f for 20 minutes. I usually control temp with a water bath if ambient temps aren't at 68f. Higher temps can give a false pass, whereas colder temps can give a false fail.

Oct 10, 2009 | 10:09 AM

72f2504x4390

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From: spokane WA

I was using 25ml of bio and 225ml of meth. Basically the same just larger scale. with 25ml, every 1ml of oil=4%

I wasn't paying much attention to temp. My last batch last night using fab's #'s looked pretty bad with the 3/27 test but my methanol was probably 50-55 degrees.

Theres so much bad info out there its scary. I wonder how many people just follow directions and never test and just run it.

Thanks guys. One more thing learned. I am sure I am not done with the questions.

Oct 10, 2009 | 11:17 AM

Rushmore X

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From: Rapid City SD

I confess, I don't test every batch... Probably should test the next one. Got spoiled by Magnesol, cured a lot of Ill's.

Oct 20, 2009 | 10:27 PM

72f2504x4390

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From: spokane WA

Thanks guys, I got it goin on now.

Still had problems with my next few batches, figured out I wasn't processing long enough. Bumped up my time from 60 minutes to 90 minutes and it took care of it.

Got to get a larger supply of KOH then it will be time to play with Methanol recovery.