nightmare batches!!!

[Vijay]

Hoping someone can shine some light on the worst lot of batches I've ever had. I'm on the third lot without actually making a batch   

The problem seems to point to glyc washing but no idea why. This lot of oil has had 4-5 pre glyc washes and still titrated at 12. I have also condensed it for 12 hours at 90c, settled for 3 days and then dropped the bottom lot to make sure there was no water.

Because of the 2 previous nightmare batches, Yesterday I did a Dr P sample using 17g of sodium to 220ml meth and let it settle all day. I had some glyc drop and some bio on the top - but loads of soap 

So today I did another Dr p with 9g sodium and 220ml meth. Straight away it went like a soft jelly. It has settled all day and no glyc drop.

Anyone ever had this sort of thing and any idea what I can do to save this batch?

Pic attached of the 2 sample batches

Cheers

Vijay

[Vijay]

the other thing I have noticed in the previous failed batches, is the less sodium I have used in test samples, the more jelly it makes - how???

[RichardP]

Can you blend it with a much better lower titrating oil?

One thing I have done with really crappy oil is give it 2 or 3 glyc washes but add around a liter of meth with 1g/l caustic after the glyc has gone in, that helped massively to help the oil convert, though with high titrating oil you will not have a high conversion rate.

[Vijay]

I blended the second lot with much better (very clean) oil then did glyc pre washes and had the same issue. That is now sitting in containers to be dealt with at a later date

I did 4-5 glyc washes as I always do. Do you mean add a litre of meth and 1g per litre of oil after each glyc wash?

[dgs]

I blended the second lot with much better (very clean) oil then did glyc pre washes and had the same issue. That is now sitting in containers to be dealt with at a later date

I did 4-5 glyc washes as I always do. Do you mean add a litre of meth and 1g per litre of oil after each glyc wash?

Hi Vijay. I think Richard means to add the chemicals to the glyc wash as it is going. This method "enhanced glycerol pre wash" was something I came up with years ago. As the chemical reaction with high titrating oil yields quite a lot of water the answer is to neutralise the oil in the presence of glycerol which has a massive affinity for water, So after the glycerol is removed

the oil is left neutral and dry.

Looking at your 1st post you have glyc washed 4 to 5 times and still your oil titrates at 12 Gosh that means your oil originally titrated at probably over 20 with sodium, thats bloody high.

Suggestion, add the correct chemicals to nuetralise the oil (use a minimum of methanol) to the glycerol you are going to use for the wash. That should leave the oil dry and neutral. I think you would be better off using potassium for the whole method, using sodium for oil that titrates so high is bound to cause issues.

One last thought, from what you say if you titrated with potassium your level would be well over 30! Wow, no wonder you are having issues.

[Vijay]

right, so is it 1l of meth and 1g of sodium to each litre of oil with each glyc pre washes? (I normally do 4 or 5 which each wash being better glyc).

So you think start doing glyc washes again with it? I only have the same glyc I've used already on this oil.  What would be the min of meth?

[countrypaul]

Each gram of NaOH you add will create about 0.45g of water, but also 7.5g of soap (assumes oleic acid). So 12g of NaOH will give you 90g of soap. For reference, a bar of PalmOlive soap weighs 90g!

It is worth titrating the oil just to be sure of how bad it is. The cost of the chemicals to just make the oil usable may be more than it is worth to you. How much of this oil do you have?

If you are willing to experiment further, you could try an acid then base approach. Treat the oil with Methanol/Sulphuric acid to esterify the FFA, followed by the normal transesterification. The esterifcation process with Sulphuric acid is quite slow but wil convert the FFA to Bio allowing the Base method to convert the oil to Bio without all the reagents being used up neutralising the FFA.

[Vijay]

Each gram of NaOH you add will create about 0.45g of water, but also 7.5g of soap (assumes oleic acid). So 12g of NaOH will give you 90g of soap. For reference, a bar of PalmOlive soap weighs 90g!

It is worth titrating the oil just to be sure of how bad it is. The cost of the chemicals to just make the oil usable may be more than it is worth to you. How much of this oil do you have?

If you are willing to experiment further, you could try an acid then base approach. Treat the oil with Methanol/Sulphuric acid to esterify the FFA, followed by the normal transesterification. The esterifcation process with Sulphuric acid is quite slow but wil convert the FFA to Bio allowing the Base method to convert the oil to Bio without all the reagents being used up neutralising the FFA.

Got to be honest, haven't got the time or head to start messing with acid at the moment, so got to rule that out.

So why am I getting so much soap, I've done glyc washes and even ran the condensor at 90c for 12 hours to remove water. Is it just bad oil = soap regardless?

[Vijay]

oh and I did titrate it which was 12

[dgs]

oh and I did titrate it which was 12

But didn't you say the 12 titration was after glyc washing. Have you titrated the oil before ie as is. It would give you a better idea of how bad it really is.

[Vijay]

I didn't mate. But what I did do was a test sample with the same good oil (after Nigel's heads up) and it titrated at 5. So somehow (and I have no idea how) the glyc washes have made my oil worse?

Just had a thought, would 5% petrol help clean this oil?

[dgs]

I didn't mate. But what I did do was a test sample with the same good oil (after Nigel's heads up) and it titrated at 5. So somehow (and I have no idea how) the glyc washes have made my oil worse?

Just had a thought, would 5% petrol help clean this oil?

What can I say, has someone pranked you with a little sulphuric in your glyc?

[countrypaul]

Each gram of NaOH you add will create about 0.45g of water, but also 7.5g of soap (assumes oleic acid). So 12g of NaOH will give you 90g of soap. For reference, a bar of PalmOlive soap weighs 90g!

It is worth titrating the oil just to be sure of how bad it is. The cost of the chemicals to just make the oil usable may be more than it is worth to you. How much of this oil do you have?

If you are willing to experiment further, you could try an acid then base approach. Treat the oil with Methanol/Sulphuric acid to esterify the FFA, followed by the normal transesterification. The esterifcation process with Sulphuric acid is quite slow but wil convert the FFA to Bio allowing the Base method to convert the oil to Bio without all the reagents being used up neutralising the FFA.

Got to be honest, haven't got the time or head to start messing with acid at the moment, so got to rule that out.

So why am I getting so much soap, I've done glyc washes and even ran the condensor at 90c for 12 hours to remove water. Is it just bad oil = soap regardless?

Not entirely surprised about your decision to avoid the acid step, it is not for the faint hearted, but I thought it ought to be at least mentioned.

Blowing air through the oil at 90C for 12 hours would result in some oxidation and creation of more FFA - how much is difficult to say without titrating it before hand and afterwards.

If the oil titrates at 12 then 10% of the oil will appear as soap, that is plenty to give you a jelly unfortunately. If you are using 17g/L of NaOH then you will have 8g/L of water present so that will catalyse more soap formation than the simple 90g from neutralising the FFA present.

I think you need to check all components again, is the solution you are using for titrating fresh and correct strength? Is the caustic soda still god and not ben left open to the air so it could absorb water/CO2?  As Dave sugestscould anyone have tampered with the Glycerol?

You could check the amount of caustic left in the glycerol with a back titration.  Titrate some acid (say 0.1*ml vinegar) and see what that comes out at (likely quite a high figure). Mix 1ml of glyc with 0.1*ml of the vineger and then titrate with your normal caustic solution the difference between the two sorts of titration will give you a value for the glycerol. If it turns out to be acidic then you have a problem.

*Not sure what quantity of vinegar you would need, or what quantity you can measure, so you may need 1ml diluted to 10 to get 1ml with the 0.1 you need, you may even need 0.01ml.

[Vijay]

Each gram of NaOH you add will create about 0.45g of water, but also 7.5g of soap (assumes oleic acid). So 12g of NaOH will give you 90g of soap. For reference, a bar of PalmOlive soap weighs 90g!

It is worth titrating the oil just to be sure of how bad it is. The cost of the chemicals to just make the oil usable may be more than it is worth to you. How much of this oil do you have?

If you are willing to experiment further, you could try an acid then base approach. Treat the oil with Methanol/Sulphuric acid to esterify the FFA, followed by the normal transesterification. The esterifcation process with Sulphuric acid is quite slow but wil convert the FFA to Bio allowing the Base method to convert the oil to Bio without all the reagents being used up neutralising the FFA.

Got to be honest, haven't got the time or head to start messing with acid at the moment, so got to rule that out.

So why am I getting so much soap, I've done glyc washes and even ran the condensor at 90c for 12 hours to remove water. Is it just bad oil = soap regardless?

Not entirely surprised about your decision to avoid the acid step, it is not for the faint hearted, but I thought it ought to be at least mentioned.

Blowing air through the oil at 90C for 12 hours would result in some oxidation and creation of more FFA - how much is difficult to say without titrating it before hand and afterwards.

If the oil titrates at 12 then 10% of the oil will appear as soap, that is plenty to give you a jelly unfortunately. If you are using 17g/L of NaOH then you will have 8g/L of water present so that will catalyse more soap formation than the simple 90g from neutralising the FFA present.

I think you need to check all components again, is the solution you are using for titrating fresh and correct strength? Is the caustic soda still god and not ben left open to the air so it could absorb water/CO2?  As Dave sugestscould anyone have tampered with the Glycerol?

You could check the amount of caustic left in the glycerol with a back titration.  Titrate some acid (say 0.1*ml vinegar) and see what that comes out at (likely quite a high figure). Mix 1ml of glyc with 0.1*ml of the vineger and then titrate with your normal caustic solution the difference between the two sorts of titration will give you a value for the glycerol. If it turns out to be acidic then you have a problem.

*Not sure what quantity of vinegar you would need, or what quantity you can measure, so you may need 1ml diluted to 10 to get 1ml with the 0.1 you need, you may even need 0.01ml.

I renewed the titratinsolution and got the same results as the old. Caustic is a new bag (but had the same sort of issues with the end of the old stuff which has always been in a small clip top container). Glycerol is left in sealed containers in the garden and doubt very much anyone has gone near it.

So if I forget about the glycerol, what can be done with 85l of this oil in the processor that's titrating at 12, what are my options? 2 stage process? https://biopowered.co.uk/wiki/Two_stage_process

[countrypaul]

I suspect the glycerol you are using has no caustic left in it, as a result it will remove water but will not neutralise any of the FFA so the titration figure will remain at 12 unless you add some more reagent (see option 3).

I see a few options:

1) Get rid and cut your losses (Ebay?)

2) Mix it with good oil (I would suggest <25%), even with very good oil that will still give you a titration figure of 3. You could then process the mix normally.

3) Follow Dave's suggestion to reduce the level of FFA, that is mix some methoxide with the glycerol and use the mix to wash the oil. Repeat several times to get the titration down to below a reasonable figure (I woud sugget a titration below 3).

4) Try a 2 stage process, but I suspect this will be troublesome given how high the oil titrates. If using 17 g/L NaOH you are adding a lot of water and producing alot of soap, as a result I would not be in the least surprised if you end up with Jelly (as you have already experienced).