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neutralizing acid
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How many grams of 90% KOH are needed to neutralize one milliliter of 99% H2SO4.


 
Registered: June 24, 2009Reply With QuoteReport This Post
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The easiest way to figure it out is to add water and do a titration.

To calculate the numbers, you will have to convert everything into Moles and "Normal".

Keeping in mind that 1 Molar H2SO4 is 2 Normal (because of the two hydrogens).

So...

1 ml H2SO4 * (density (grams/ml)) * 0.99 will give you the weight of H2SO4 in grams.

Now sum the atomic weights of the elements in H2SO4 to get grams/mole

Divide the grams above by grams/mole to get moles.

Multiply by 2 to convert from "Molar" to "Normal". And this should be the number of moles of KOH you need.

Now multiply your "Normal" quantity by the grams/mole for KOH to get grams KOH.

Divide by 0.9 and you should have your amount.

It always is very helpful to keep track of the units throughout the calculations as you need to end up with GRAMS and the units will help guide your multiplications and divisions...
 
Location: Oregon | Registered: October 17, 2007Reply With QuoteReport This Post
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Thanks, I guess an internet search is in order for molecular weights.


 
Registered: June 24, 2009Reply With QuoteReport This Post
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Great, I'm working so in between patients I've come up with, 2.31g KOH(90%) will neutralize 1 ml H2SO4(99%). Does that sound about right, so 190ml H2SO4(99%), 438.9 g of KOH(90%) is ulitized, 1911.1 g KOH(90%) left for base rxn.
Trying to use this to tweek my numbers, less soap.
Thanks again Keelec


 
Registered: June 24, 2009Reply With QuoteReport This Post
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fuelfarmer
-are you neutralizing acid after AE? if so ,after AE do a simple titration the titration amount in gr KOH or NaOH will neutralize the acid since the acid is part of the total acid number for the oil . Tom


" 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.
 
Location: Manitoba Canada | Registered: March 24, 2009Reply With QuoteReport This Post
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Biotom, but won't that also neutralize the remaining FFA?

I guess my question is... in trying to determine how successful the AE process was, how does one determine how much of the final titration is due to the acid that was added versus the remaining FFA?

So for example, if I started with 76L of oil that titrates at 20ml NaOH solution (roughly 15%FFA), then added a total of 183ml of 99% sulfuric and 10% methanol. If my final titration comes in at 8ml NaOH solution. How much of that 8ml solution is simply being used to neutralize the acid (and hence, what amount is due to remaining FFA)?
 
Location: Atlanta, GA USA | Registered: March 10, 2003Reply With QuoteReport This Post



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So based on keelec's post...

183ml * 1.84g/ml (density of sulfuric) = 336.72g of sulfuric.

336.72g / 98.08g/mol = 3.43mol sulfuric

3.43mol * 2 = 6.87mol Normal

6.87mol * 39.99g/mol NaOH = 274.6g NaOH required to neutralize the acid (assuming all 100% purity).

Does this look correct?
 
Location: Atlanta, GA USA | Registered: March 10, 2003Reply With QuoteReport This Post
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and if that IS correct, then...

My example batch would need 274.6g NaOH for the 76000ml batch, or 274.6g/76000ml = .0036g/ml

If the titration solution is 1g/L NaOH, .0036g * 1000ml/g = 3.6ml of the titration is due to the sulfuric, meaning... 8ml titration - 3.6ml to neutralize acid = 4.4ml to neutralize the FFA, meaning my final resulting FFA is around 3-3.5% FFA

(again assuming 100% purity and assuming the sample of oil to the titrated is actually 1.1ml due to added methanol.


Again, anyone care to check my math on this?
 
Location: Atlanta, GA USA | Registered: March 10, 2003Reply With QuoteReport This Post
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neutralizing the drainage ONLY the acid remaining in the oil will be neutralized immeadiatly once the methoxide is introduced. an acid and a base can not co exist in the same container at the same time. Tom


" 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.
 
Location: Manitoba Canada | Registered: March 24, 2009Reply With QuoteReport This Post
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Not sure I understand your reply Biotom.

My goal is to understand how much of the titration after AE is due to the added acid.

I understand that both the added acid and the remain FFA will be nuetralized by the base stage, and that the titration after AE determines the total base required to neutralize both, but my question has more to do with understanding how successful (or not) the AE stage actually was in converting FFA.
 
Location: Atlanta, GA USA | Registered: March 10, 2003Reply With QuoteReport This Post
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what are you trying to neutralize?
the oil after the AE stage?
the draining from an AE stage?

oil after AE stage..don't neutralize it..its not necessary. the titration takes care of it.

for draining from an AE stage?
I just dump this mix of methanol/water/acid into my glycerin storage for methanol recover. then I don't worry about the acid..lots of excess KOH/NaOH in the glycerin. This get converted into water and a salt.

for the change in titration caused by the acid alone..that's easy..but solved in a different manner.
take neutral ph water add 1ml of acid..how many mils are needed to neutralize or bring the ph back to neutral..for KOH(90%) its about 2mls( using a 1% KOH solution).

-dkenny


'84 bluebird school bus, DD8.2L turbo( 4/2011, the bus tranny has died..Frown 8.23.11 bus driven to scrap yard Frown )
2006 Jeep Liberty CRD Smile - the wife's
99 dodge 2500 5.9l 24v..-mine Smile
everything run B100 when its warm enough Smile
 
Location: RTP, North Carolina | Registered: December 15, 2004Reply With QuoteReport This Post
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I probably should have started a new thread, as I am not looking to neutralize the acid.
Again, I was just looking for a way to determine how much of the titration after AE was due to the added acid, and how much is a result of residual FFA. This thread was kinda on that track.
That's all.
At this point I think I understand how the determine that.
Thanks!
 
Location: Atlanta, GA USA | Registered: March 10, 2003Reply With QuoteReport This Post



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2T for each ml of acid/ltr of oil (if using koh)


" 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.
 
Location: Manitoba Canada | Registered: March 24, 2009Reply With QuoteReport This Post
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astrorob,
no problems.
you might enjoy reading the 70+page sticky at the top of the AE section. its a thread that I started to learn more about AE.
lots of questions are answered. Sure it'll take some time..but if you want to learn about AE..Start there.

lil'fuelfarmer, returning to your question??has it been answered well enough?

-dkenny


'84 bluebird school bus, DD8.2L turbo( 4/2011, the bus tranny has died..Frown 8.23.11 bus driven to scrap yard Frown )
2006 Jeep Liberty CRD Smile - the wife's
99 dodge 2500 5.9l 24v..-mine Smile
everything run B100 when its warm enough Smile
 
Location: RTP, North Carolina | Registered: December 15, 2004Reply With QuoteReport This Post
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