İ made bio 3 weeks ago in first time in my life. İ do the 3-27 test. And it shows me i have 35 percent unreacted oil. And i reprocess my batch. Now i have 8 percent unreacted oil but there is a big but in here.
İ was passing the 50-50 water test. But i cant pass it now.
İ poor 200 ml water and 200ml bio in a cup. And shake it. İts been a 1.5 hour and its nor seperated yet. And i think its not gonna seperated.
Can i save this batch. İ spend lot of time and lots of money. What can i do guys ?

It sounds to me that you have some soap in your biodiesel, since it does not separate from water. So put some inexpensive sodium chloride salt into the biodiesel and water that does not separate. This may cause it to separate.

okey sir but i use to pass 50-50 soap test. and i reprocess my bio and drop the unreacted oil percentage. now i cant pass it. i have 40 liter bio how many grams do i need to use this salt ?

As much as it takes. Start off with about 1-2 lbs (about 400-800 grams)
Dissolve in water and then dump it into your biodiesel.
Stir for about 10 seconds, then walk away for an hour. When you return see if it's separated.

I did a whole article on the how & why here:
http://www.utahbiodieselsupply...ing-and-curing-them/

And also a case study I affectionately called The Emulsion From Hell and How We Broke It
http://www.utahbiodieselsupply...and-how-we-broke-it/

It was quite the mess that we were able to save

sir its been two hours to i made the test. i just checked the bootle twenty percent of the biodiesel separed but on the top still milky. if i wait 2 or 3 days is this going to seperated. ?
and really i dont wanna spend another money on my fail batch. if i have a 100 percent chance to save this i am gonna do it. but if i dont i am gonna try to make another batch.
and sir if i do it right next time can i use it on passat pd engine ? i found some articles some of them absouluty yes and some of them absoulty no. what should i do ? butaway passat 2008 pd engine

mustafa; You might try making small 1 litre batches of biodiesel to learn how to do it, before you make big batches. It probably will save you money. I think you should try to get 99-100 per cent methanol to learn how to make biodiesel. A small 20 litre barrel of this type of methanol costs something like 40-60 American dollars here.

i should do this earlier i think idiot me. i have emultion now. when i do 50-50 shake test. it turns out white. and 1 day later it has a 20 percent orenge colur stuff in the bottom.
can it be saved or its too later.
and i dont understand how table salt or anothe salt make the soap go away ?

In the past I believe my emulsion cleared faster when it was warm, not cool. You might try putting it in the sun with mirrors near it, reflecting sunlight onto your test batch bottle. I don't know how to explain why dissolved salt causes the emulsion to separate, but it does sometimes. The type of salt I used was table salt without iodine in it. The salt might be called sea salt and sodium chloride. After the emulsion clears. The biodiesel should be water washed two, three or four times more with clean water to wash the salt out. If salt is in biodiesel used for motor fuel, it is bad for the motor. After water washing the biodiesel will be wet, so it needs to be dried after water washing.

The Salt dissolves into the water and increases the specific gravity (only slightly) but this is enough to make it sink to the bottom,Usually works really well.
As Wesley says as warm as possible is better 60degs C is ok.

On the question of a using a 2008 Passat pd engine and biodiesel, does the car have a diesel particulate filer(dpf)? PD Passat engines of that year in Europe and Nth America have a DPF. Elsewhere in the world.....I don't know.

Assuming the car has a DPF, I suggest your choices are twofold.

1 Leave the DPF on the car and only use biodiesel on long journeys, when the engine temperature will be high enough for long enough to do passive regeneration of the dpf. Minimum of 30 minutes driving...longer is better. You can check on the build up of soot in the DPF using a VAGCOM lead and VCDS.
or
2 Physically remove the DPF matrix and have the ECU reflashed to do a 'dpf delete'. The exhaust will have a characteristic smell of barbecue thereafter.

In my experience, PD engines without DPF work fine on biodiesel, for both long and short journeys. PD engines with DPF will drive fine on long journeys. They will also drive fine on short journeys, certainly in the short term. However,there is a concern about biodiesel use with DPF equipped engines, where use is for short journeys. The concern is related to production of soot and clogging the DPF filter....over time. What that time is, I don't know. Nor have I been brave enough to try and find out. In both cases (PD engines with DPF and without DPF), it is implicit that the fuel must be of good quality.

Last point of advice......if it is a BXE code PD engine....walk away from it. They have a habit of putting a connecting rod out through the engine block. Google "BXE conrod" to find out more.

I hope I have expressed my points clearly and that it proves to be helpful

Table salt work in another way too.
You can check if you can wash your hands with soap in salty water.
The soap bar or soap liquid doesn't make bubbles in salty water, that's why soap breaks the emulsions including the fact of changing gravity of water.