I haven't fiddled with bio for a long time as I found my 1HZ diesel and 1989 300d ( both IDI )engines likes veg oil and diesel mixed together.The portions are dictated by the season.
I'm doing 1 litre batches of bio at present to get my hand in again.
I took a litre of veg oil out of a settling tank and reacted it with 7.5 g naoh and 160 ml meth at 50deg c (the 7.5g was a guess... no titrating fluid but I do have electronic mini scales for the 7.5g ) and achieved separation.
Set that glyc aside for future pre treatment of fresh oil in the next one L batch.
The barely bio failed a 3/27 with about .75 ml fallout and very cloudy. (No washing) 3ml oil measured by syringe
Reacted the barely bio with another 2.5g naoh and 50 ml meth at 50 deg c (the 2.5 g naoh was yes another guess amount) separated a small amount of glyc and did the 3/27 (actually was probably 3/40 as had no accurate way of measuring 27 ml at this stage).
Result was still a smaller fail and cloudy.
Maybe 0.3ml dropout.Set that bio aside.
Pretreated the next one litre of fresh oil with the reserved glyc at 50 deg c and let sit after mixing and sitting for 15 min. Drained the glyc and discarded it.
Reacted the oil with 6.5 g ( measured on scales )naoh and 160 ml meth ( again a guess at the naoh quantity but glyc pretreat pushed me to guess lower)...yep...plenty of guessing I know But its early days yet
Much smaller amount of glyc dropout this time.
Drained the glyc and immediately did a 3/27 but again would have been 3/40 (still no accurate way of measuring 27 ml) and no washing.
Sample went clear in maybe 10 sec and a quantity of about 0.2 ml small flakey bits of soap? settled out (sucked up the flakes in a pipette)
Temp in the shed was lucky to be 14 deg c as was the temp of the methanol.
I brought the 3/27 test inside for the night house was approx 18-21 deg c all night ( combustion heater ).At 8am and 18 deg c the 3/27 test had no dropout
I'm asking all the other learned people here
1. the fast and clear 3/27 on the second batch ( but really a 3/40) was a good indication of a pass? (I could measure 40 ml accurately).The 3/27 was a 5 soft shake affair in agitation terms.
2. Did the extra methanol in the 3/27 give a false result?
3. What does the production of soap flakes indicate ? Excess NaoH ? ( they looked like pale white/ yellow floaty things that did join together in a rough edged shape in the bottom of the vessel. )
4. Can I deduce that the production of small amounts of soap in a 3/27 (in addition to a fast clearing meth sample in the 3/27 ) also constitute a complete reaction?
My reason for aiming so high is my wife drives a w163 ml270 cdi ( with all the common problems leaking everything under the bonnet) and we plan to fuel it with bio/diesel blends
Yours in gloves Peter
After reading this again (as you do) soap flakes =water? ... but none in first test, and glyc pretreat in the 2nd test?...
oil came from the top of half empty 1000L storage been sitting for 8 months
The pre-treatment is the first stage of a multi-stage reaction. There is a trade-off when doing multi-stage reactions.
Within reason, the more stages you perform the less total chemicals are required but the longer it takes to do the total reaction.
Right now, because you do not know how much chemicals you used, there is not really much else someone can say with any certainty about what you have done.
It will be interesting to see what you achieve when you can do some accurate measuring (temp and quantities)
The grams naoh are accurate as is the quantities of meoh in the methoxide.
Im happy with the methoxide being accurate.
My only dodgy bit is 1n the quantity of meoh in the 3/27 test, hence my term 3/40
So...is using more than 27 ml meoh in the 3/27 going to give an accurate result?
Cheers and thanks
The methanol volume is a bit low. s/b 200ml/Lt oil. Is it is new oil then 7.5gr.Lt is more than enough. Prof Van Gerpen suggests as high as 9 NaOH + titration. The 9 is usually reversed for those using KOH, but who am I to argue, although I personally think 9 is high for NaOH and use 5.5 + titration, which usually puts me around 7.5 NaOH total.
** Biodiesel Glycerine Soap - The Guide
- on 5 continents helping people make & sell soap from the Biodiesel Glycerine.
I do not know what flakes in the 3/27 test mean.
One post says they are a carbonate caused by using less than fresh NaOH.
Use the find function to search for flakes.
There are lots of variables in processing biodiesel including but not limited to:
Amount of chemicals used
How dry the oil is
Titration of the oil.
The tune playing on the radio
If the 3/27 test that went clear in 10 seconds or less was performed at 20C or less I would think that is good.
The formula 5g+titration NaOH mixed into 200ml methanol per litre of oil being reacted in a single stage is designed to "Just Scrape In" to meed ASTM conversion
As Legal Eagle has pointed out, more chemicals will increase the likelihood of passing the 3/27 test.
Also, if you do a two stage procedure properly, you can use less total chemicals for the same results.
My experience with flakes in the 3/27 test, both white and amber in color, is that they disappear if you do a reprocess on the batch what are they?
" I don't know what I don't know until I know"
1994 GMC 6.5 Tubo 2005 Dodge ram 3500, 3 VW's 2000, 2002, 2005.
Thank you people for taking the time to reply.
Oil is used fryer oil ...nice colour.. not too dark at all.I've started separating dark and light oil in 1000l tanks now. The dark stuff can get made into barely bio and go in the IDI engines
After doing more experiments with glyc pretreat and base/base on the one litre samples I have got down to 4.8 g naoh/150 methanol and 1g/50 ml as a base/base reaction that leaves a quick clear 3/27 with no floaty bits.
Tilly the naoh is 2 years old but in a sealed container (so theres a possibility on your old naoh idea; only one cricket ball sized clump in 15 kg ) but flows very nicely.A new bag will get purchased soon.
I'll reinstate my old reactor in the shed and work on 120L batches before I try to get fancier.
I'd forgotten how sweet the smell of biodiesel is
It sounds good.
So you have settled on a three stage reaction.
Assuming your glycerine is from an NaOH reaction, have you had any problems with the glycerine going solid?
Have you titrated the oil?
A quick additional thought.
Because you are using a three stage procedure you should be able to reduce your total Methanol consumption.
Right now you are using more methanol than most people use in a single stage reaction.
I have been using the glyc from previous reaction straight away to get away from hard glyc in -1 deg c temps we get at the mo.
I've been leaving the pretreated oil in the container until needed
No titration yet but I must
I've titrated before to what i thought? was a satisfactory accuracy level but rarely passed a 3/27.
When I've really got my sh1 t together I'll have a crack at getting cheaper.
My procedure this time is far more positive than it was 2 years ago. i.e. no big storage vessels then ,variations in oil quality etc. Its amazing what a 'stand back and watch' approach does for the self confidence
Does anyone else feel that biodiesel is going thru a very testing time with the proliferation of CRD engines and DPFs tending to scare the common man from having a go at it?
I have a feeling that the recommendation of all new car manufacturers that B5 is all they will warrant is based apon the premis that straight veg oil can be called bio.
If this is their thought then 5% is all they'll put up with.
Alexander Noack at www.anc.me - click on the flags to convert it to english ( no affiliation ) has very clever conversions for CRD engines.
He also makes replacement DPFs that u can use to replace the original manufacturers DPFs.
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