Curry oil cock up.

[Glycer-rides]

 At least it was a nice day to spend a la shed...doing 4 stages.

This oil, from a new source, looked good. Clear reddy-orange with a spicy nose to it.
Settled for a month, bottom 10% drained off, glyc. washed. That should be good to go, easy peasy...
I will spare the details, but:
S1 27% uc.
S2 18% uc.
First ever S3.... 15% uc.
S4 ......14% uc!

Low glyc yield all round. On the latter stages it wasn''t drained before the next stage.
In the dim and distant past I recall reading of curry oil probs? Any ideas?

[Tony]

Perhaps it's a mix of veg and mineral oil?

Whenever you think you've got it all in hand, there's a batch that likes to show you you're not as much in control as you thought

[Glycer-rides]

Thanks Tony, that thought crossed my mind.
Too true!

I suppose I might ask N***, in a nice way, where he gets it and why he didn't filter it for his wvo use.

[dgs]

I have had similar batches in the past, probably due more to wet oil, but not as bad as that.

it is never a good idea leaving the glyc in between stages, it 'holds on' to some of the next stage chemicals.

You say low glyc yield, but if you added so much excess chemicals surely you would end up with more glycerol than normal.

[Glycer-rides]

I'm sure it wasn't wvo wet, Dave.

The glyc volume decreased 35% after the glyc wash. Something's transfered across, hopefully not all soap...

With wet wvo, the glyc wash turns 'brown and bubbly'.

[dgs]

OK, I understand now.

I wasn't suggesting it was water that is your problem in your case. I suppose it could be mineral oil, but how did it get in there.

I wonder if anyone has ever done a dropout on mineral oil, just to see the phase split and to see if any oil dissolves into the methanol.

I will do it now and report back.

[Glycer-rides]

Well, used engine oil doesn't split with glyc, so I'd expect mineral oil to perform the same with meth?

So how did 25L of clear (not used) mineral oil end up in my wvo?


I've now asked the guy I got it from.

[dgs]

I added 10mls 10-40 mineral oil to 90 mls of methanol. Gave it a good shake. An emulsified layer of about 40mls settled. The methanol phase is cloudy. The emulsified layer is semi-solid, if the tube is held horizontally, the meniscus hardly alters. It has now been 15 mins.

If nothing alters, could we assume that if your bottom phase goes clear then mineral oil is not present?

I have done tests with glyc and WMO, to see if the glyc removes any suspended carbon. As you say there does not appear to be any split. However, due to the SG difference between the two, I think they do split, but the WMO transfers so much carbon to the glyc that it masks any visual split.

[dgs]

It has now been 75mins since the test started, the bottom layer has reduced to 25mls and the methanol phase is nearly clear. The emulsified layer looks like dessicated cocanut, only a dirty orange colour.

i have just started another 10/90 which has 1.5mls of 10-40 motor oil and 8.5mls of finished bio, with 90mls of methanol. (I think this more replicates what you may have)
At the moment there is 8mls of the same bottom layer. (dessicated cocanut)

As said if your bottom dropout layer is clear, from the above results I would doubt the reason for your unusual reaction is mineral oil.

[Glycer-rides]

Thanks Dave, useful tests there.
The wvo comes from a trustworth source and he has confirmed it was his normal stuff.
It must be me! The drop out is exactly the same shade of orange as the wvo was.

With the excess KOH added having not much effect, I would have expected jelly territory but there was no sign of this.

I gave up last night and stopped the inaction with a 5% wash. I will drain tonight. Probably should have left it 'live'.

[dgs]

Certainly a strange one Andy.

I've just checked the tests again, just mineral oil shows a little under 25mls of 'whatever' and the bio/mineral oil shows a little under 8mls. I don't think there will be any more change now.

The dropout test is measuring bio/oil in roughly a 50/50 ratio. We rely on the soluble proportion of the diglycerides and all the monoglycerides to roughly equal the amount of bio contained in the oil dropout. (the reason why the test usually works)

If for some reason these di's and mono's are in a much higher proportion in your partly converted oil it would account for what you are finding, but I have no idea why this should be.

[Glycer-rides]

I left the 5% wash 24 hrs before draining it. What drained out looked unexceptional.
Heated it back up to around 50C and glyc washed the bio. Again, what came out looked normal, no real loss of yield.

I did a 10/90 on the bio and got a similar result, 15% u/c, rising to 17% u/c the next day.

Tonight I did a 500 mL Dr. Pepper on the bio to see if I could get a full conversion.  (measuring 3g KOH was hard, no spare batteries left for my 'drug dealer' mini scales...)
It processed OK, no soap or mono/di layer BUT the 10/90 is showing...................15% u/c, which I expect will rise to 18%.

In summary, still stumped!

[Tony]

Are you sure the meth you are 3/27 testing against is pure?

I've had problems with dropout before, and that turned out to be because I had left the top off the jar of meth I used for this testing, and it must have absorbed some moisture from the air.   It seems only a tiny amount is needed to mess up the test.

Alternatively, have you got some "known good" bio to double check your 3/27 test with?

There was a chap I met locally that called me over to look at an odd batch.  3/27 gave dropout that formed into balls.  Couldn't get any further conversion with a Dr Pepper, and his meth was pure enough.  Never did figure that one out.

[Glycer-rides]

It's pretty new decanted Trinity reclaimed, so I think it's OK. I'll try another cubie.

That's a good idea, Tony. I'll try testing some known good bio.

My drop out also has a ball-like, 'spawny' look to it initially, which later evens out to look normal.

I'd can this batch...if I had any cans!

[dgs]

I was worried about this exact same thing when I started using Trinity reclaimed. I did some comparative tests with virgin stuff and the dropout was exactly the same.