Author Topic: Help! Reaction not happening.  (Read 95 times)

Offline Sonex

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Help! Reaction not happening.
« on: July 13, 2025, 12:44:23 PM »
Having made biodiesel for years, I've had this problem come up again.  The oil titrated at about 4.  I mixed KOH in the methanol until it dissolved.  The mixture then got mixed into the heated up oil.  I stirred it up.  A couple hours later, I came to drain out the glycerin, but there was none.  No reaction took place.  WTF?

Could the oil contain cleaning agents, which stymie the reaction?  What should I do with this bad batch?

Offline neisel

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Re: Help! Reaction not happening.
« Reply #1 on: July 13, 2025, 01:14:07 PM »
"I've had this problem come up again.."

How did you fix the problem when it happened before?

Please include the quantities of chemicals, WVO etc you used. It might be helpful for those who understand chemistry.

Offline Sonex

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Re: Help! Reaction not happening.
« Reply #2 on: July 14, 2025, 02:20:18 AM »
The last time this problem came up, I ended up throwing out the whole batch and starting over.   :-[

It's about a 35 gallon batch of oil.  I poured left over glycerin from a previous batch in it and let it settle out and drain off before mixing in about 6 gallons of methanol with approx 50 oz of KOH dissolved in it.

Does anyone know of a university lab, which would analyze a sample of what I have?
« Last Edit: July 16, 2025, 11:29:10 AM by Sonex »

Offline dgs

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Re: Help! Reaction not happening.
« Reply #3 on: July 17, 2025, 05:02:07 PM »
The last time this problem came up, I ended up throwing out the whole batch and starting over.   :-[

It's about a 35 gallon batch of oil.  I poured left over glycerin from a previous batch in it and let it settle out and drain off before mixing in about 6 gallons of methanol with approx 50 oz of KOH dissolved in it.

Does anyone know of a university lab, which would analyze a sample of what I have?

Don't throw the batch away, there will be plenty to salvage. i don't know why this has happened but I'm sure you will have had a reaction.

so....heat up your batch and add what glycerol you have (even the stuff you used to pre treat it with) when it cools you will have a layer of glycerol with bio on the top.

Do you know how to do a 10/90 dropout test.
FOC water tests by Sandy brae or Karl Fischer for forum members.

Offline Sonex

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Re: Help! Reaction not happening.
« Reply #4 on: July 18, 2025, 02:53:40 AM »
Any idea how to get glycerol if I'm out of it?

Offline dgs

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Re: Help! Reaction not happening.
« Reply #5 on: July 18, 2025, 10:48:37 AM »
Any idea how to get glycerol if I'm out of it?

Sorry, no. Thats why I mentioned the glycerol that you washed the oil with, not ideal but better than nothing. You can use pure glycerine but it is expensive here in the UK, i don't know about the States.

Anyone make bio who is close to you to help you out.
« Last Edit: July 18, 2025, 10:50:41 AM by dgs »
FOC water tests by Sandy brae or Karl Fischer for forum members.

Offline Sonex

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Re: Help! Reaction not happening.
« Reply #6 on: July 19, 2025, 06:08:36 PM »
Thanks for the suggestion.  I just ordered a couple gallons of glycerine to use as you have suggested.  I'm curious myself to see if it has any effect.
« Last Edit: July 19, 2025, 10:32:20 PM by Sonex »