I am confused by what is meant by 0.01N, 0.1N HCl.
Last I worked with acids such as HCl, it was in highschool chemistry. I do recall seeing HCl referred to as 12m 3m or 1m, in which the m stood for mol, and the numbers were used to denote concentration/strength of the acid solution. Is this what you meant to type, but accidentally hit the N key (which is right next to the M key on a standard QWERTY keyboard) or is the N supposed to stand for something else?

I remeber using normality in chemistry last year to measure concentration. I believe it was the molarity multiplied by something, can't remeber anymore.

"Another concentration unit often used in titrations is normality (N), which is the number of equivalents per liter of solution. It is useful because mole factors are not needed." Simple google search.

Here are a couple of pics of the jar of syrup after the spin wash. I tried to spoon some of it out and pour it back into the jar to show the consistancy.

Pic1
Pic2
Pic3

I will take some pics tonight of the inside of the bowl and the remaining syrup. I stopped the filter last night at about 380ppm. I restarted it about 2 hours ago and plan to let it run for another 2 hours. I checked the ppm about 1 hour ago and it was 228ppm.

Once I get the 2 tank system set up, I bet I can wash the fuel in about 2 hours. At 75psi, the bowl is spinning at 7000rpm with a flow rate of 2.3 gallons per minute.

So a 20 gallon batch should make a single pass in 10 minutes. Transfer back, say 10 minutes, and refilter. 20 minutes per cycle, 3 cycles per hour. 6 full 100% fuel passing through the filter cycles may do the job. Once I get it set up (about a week out waiting on a pump), I will post those results.

Is this the one your using? Model 60 service manual

quote:

Originally posted by Koreth:
I am confused by what is meant by 0.01N, 0.1N HCl.
Last I worked with acids such as HCl, it was in highschool chemistry. I do recall seeing HCl referred to as 12m 3m or 1m, in which the m stood for mol, and the numbers were used to denote concentration/strength of the acid solution. Is this what you meant to type, but accidentally hit the N key (which is right next to the M key on a standard QWERTY keyboard) or is the N supposed to stand for something else?

I saw it mentioned that way as mol in one of the van gerpen papers. I think nomality and mol are the same. Or at least I've been intrepting it that way. That term has caused some confusion before, so hopefully a chemist will speak up and set me straight.

Should have done a little searching before:

http://chemistry.about.com/library/weekly/aa081003a.htm

I have some text to change from (N) to (mol).

quote:

Originally posted by RickDaTech:
Is this the one your using? Model 60 service manual

Mine is an older model than that, but is the same.

Would a certrifuge do the same thing?

My wife has a Dyson. She wouldn't like me filling it with biodiesel. Great vacuum, BTW>

Bowl1
Bowl2
Filter1
Filter2
Jar of Bio

Ran the pump for another 3 hours tonight. Soap count is now 121ppm. Based on the pics above, there is still more to pull out. I will let it go another few hours tomorrow night.

I did a test on the syrup, not sure if I did it right:

1. placed about 50ml of isopropyl (91%) in a jar.
2. added 1ml of syrup (that was some thick stuff to suck up a 1ml syringe!)
3. added 10 drops of bromophenol blue
4. added 6.5 ml of 0.1N HCL until the solution turned yellow

Rick da Tech,
What would that make the soap count in parts per thousand?

quote:

Originally posted by bio-LOGIC:
Would a certrifuge do the same thing?

That's what this type of filter is.

One other thing to note.

Both of these batchs were made from a new 50lb pail of KOH from Boyer Chemical. Before, I used their 10lb bags of KOH. The KOH looks the same and appears to work the same. Not 100% sure the purity is exactly the same between "batchs" of KOH though.

Could this pail have more NaOH in it than normal (I thought I ready somewhere that 90% KOH had 10% NaOH, not sure on that though). Has anyone tried a 75% KOH + 25% NaOH for a batch of BD? Would that even do anything? In other words, would your soaps be "more" solid with more NaOH percentage? Or would you just get some solids and some liquids?

Too many questions....

For those looking at these filters, you need to also have a pump to drive it. At one time, I was using the clear water pump and it "worked". I am not sure the pressure it put out but it did run the filter. The pump was under MAJOR strain though. Sounded like you closed a valve 90% while running the pump. Can't be good on them.

Lets go back to the source material for the soap test.

From: http://www.nrel.gov/docs/fy04osti/36240.pdf

If you take the ml of HCl added for the first titration and do the following calculation:
[“B” ml of 0.1N HCl] x [1 liter/1000ml] x [0.1 moles of HCl/liter]
x [1 mole of soap/mole of HCl] x [320.56 g/mole of soap] / [grams of sample] = grams of
soap (as sodium oleate) per gram of sample.

[6.5ml of 0.1 N HCL] x [1 liter/1000ml] x [0.1 moles of HCL/liter] x [1 mole of soap/mole HCL] x [320.56 g/mole soap] / [.87 grams of sample] = 0.24 grams soap/ gram of sample or 25% soap.


The .87 grams weight for the sample is the weight for a ml of biodiesel, so you could probably get more accurate by weighing out a gram of the soup for your test.

The 304 multiplyer is for Na soaps, it becomes 320 for K soaps.



Always best to do the math and be right rather than spew and be wrong. I should learn better.

The other 10% is more likely K2CO3, potassium carbonate. KOH changes to this when it comes in contact with CO2.

Just measured a sample of the syrup.

1ml = .96g

Would that make it about 22% soap then?

It took about 30 seconds to suck up 1 ml in the syringe. Some pretty thick stuff.

Sounds right to me. You should be able to go back to your original soap tests and balance out the soaps, as in soap in prespun biodiesel - soap spun out = soap in finished product.

I'm not going to try it on account my head is already hurtin from doing too much math.

quote:

Originally posted by bayshorecs:

quote:

Originally posted by RickDaTech:
bayshorecs,

Any guesses on the purity of the soap?

I still have the soap in a jar. What tests do you want done?

Working it out in my head:

1ppm=1mg/1L

2000ppm = 2000mg/L = 2g/L * 68L = 126g of soaps.

I have about 500ml of the syrup. Anyone able to work this out further?

Could this be right...

1. I have about 600ml of syrup which comes out to about 22% soap based on the test
2. 22% * 600ml = 132ml * .96g/ml = 126g of soap.

Do these number actually work out or is it just a freak thing? As I have most of the soaps out (down to 121ppm) and the 600ml is a "guess" (could not physically capture 100%, I DO have about 500ml), it seems like according to the math, it should be about done. And the soap test of the BD shows it is about done.

Really should have studied more chemisty and less computers...

bayshorecs,
Sorry I didn't check the links before posting my question about using a centrifuge. I've been drooling over centrifuges for a while now.

I've had a somewhat unrelated question that has gone unanswered and I hope you don't mind helping me with it, since you have experience with this equipment.

Can you use a centrifuge to dewater WVO?

bio-LOGIC,

here is a long thread where the SVO guys are asking that same question. From just reading it, I think the jurry is still out.

http://biodiesel.infopop.cc/eve/forums/a/tpc/f/159605551/m/2001011761

quote:

Do these number actually work out or is it just a freak thing? As I have most of the soaps out (down to 121ppm) and the 600ml is a "guess" (could not physically capture 100%, I DO have about 500ml), it seems like according to the math, it should be about done. And the soap test of the BD shows it is about done.

Aint it grand with the math works out like it's supposed to?

quote:

Originally posted by bio-LOGIC:
Would a certrifuge do the same thing?

My wife has a Dyson. She wouldn't like me filling it with biodiesel. Great vacuum, BTW>

The dyson is a cyclone rather than a centifuge. Vormax filters and RCI filters are cyclonic. The spinner is, as has been said, a centrifuge.

I just happen to have a junk dyson or three to play with so felt inspired.