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Titration does not want to drop.
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I knew I was getting a bit too cocky after my success a few weeks ago with that T20 oil. I have a load of oil at T9 that was nice and dry. Added the methanol and sulfuric in proper portions, stirred a half hour and let it set with heat at 135. Came back this morning, no water to drain, stirred it and titrated it still at 9. Hmmmm, so I added 200 ml of sulfuric and a couple more gallons of methanol stirred a half hour and let it set. Titration has dropped to 8.5 after about 36 hours of treatment.

I do not know if there is some kind of contamination in the oil, it is a collection mixture from four sources. Any ideas as to what causes the AE treatment to have no efffect?

Norman
 
Location: Lincoln, NE | Registered: April 10, 2006Reply With QuoteReport This Post
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Why are you not mixing it?

That doesnt sound right


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Registered: March 09, 2006Reply With QuoteReport This Post
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-Mixing in the ae process causes higher ending T than mix and sit!!

Norman,
- are you sure there wasn't any caustic in the processor when you did the ae treatment. we have found that residual caustic from previous base processing can neutralize some or all of your sufuric acid,depending on how much caustic is there.It takes very little caustic to neutralize the acid. there is no need to add any more methanol in this batch, just add a more acid


" 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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Ditto on what Biotom said, although I have encountered a new problem...

It seems that some oils, perhaps because of high monoglyceride content or high animal fat content (just speculating at this time), will hold the water and make our oil appear to pass HTP but still have a high levels of moisture. I am stilling drying a batch after 16+ hours AFTER passing HTP and still have substantial moisture coming out as steam.

As we know water kills the reaction, and unfortunetaly I don't think HTP is a good enough indicator of dryness for AE especially considering these oils typically have either high monoglycerides or animal fats or both.
 
Location: Buckeye | Registered: July 07, 2009Reply With QuoteReport This Post
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Buckeye
-monos can't be an issue here, since we are only working with ffas (unattatched) In mono, one fatty acid is still attatched to the glycerin backbone,. I'm going out on another limb here, Big Grin Big Grin because I don't remember the whole story Frown, but one of the fatty acids has a phosphorus component which will hold water that is very hard to get rid of.
-the result that Norman is experiancing is for sure caused by , water, caustic or a combination of the two
-I agree, hpt is not a good indicator of water content for ae process, time to build a manometer. I just brought a container of carbide into the shop, and it's still good after all these years (30) I put a couple rocks in a jar of water and lit the acetylene, it burned for several hrs. 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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Phosphorus component, interesting, thats a new one to me, Ill have to do some research! Do you know what fats or oil bases carry the phosphorus fatty acid?

Back to your other part, yes to we are working with FFA's, however not 100% FFA's, the remainder of the oil would be a mix of tri, di, and mono glycerides, and Im guessing a high concentration of mono's and di's for extremely high titrating oil (like the stuff I work with) due to the breakdown of so many triglycerides into these other components and FFA's.

Basically, you are correct we are only working on the FFA's, however the other molecules are also in the oil solution in abundance including monoglycerides and they are making my life a real pain the last couple days Mad

Its a new sewage oil source....
 
Location: Buckeye | Registered: July 07, 2009Reply With QuoteReport This Post



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I guess carbide doesnt have an expiration date.

And my wife tells me I am bad about never getting rid of anything! Big Grin
 
Location: Buckeye | Registered: July 07, 2009Reply With QuoteReport This Post
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Buckeye
- you can't be forced to throw away Big Grin Big Grin. I have it hiding in an old vehicle on the farm 1,000 lbs, need some!
- the higher the T of your oil the more monos and dis for sure! but I don't under stand how they can create the problem, what am I missing Confused.I have also experianced the issue of passing hpt and still having what appeared to be steam coming off the top of the processor, I even posted a what is this picture, and I still don't know where what looks like moisture comes from (it did not steam up cold glass),and it doesn't show up on the hpt 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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quote:
Originally posted by Biotom:
Buckeye
- you can't be forced to throw away Big Grin Big Grin. I have it hiding in an old vehicle on the farm 1,000 lbs, need some!

You must not be married... Big Grin,
How about a trade for some sodium bentonite! Big Grin
quote:

- the higher the T of your oil the more monos and dis for sure! but I don't under stand how they can create the problem, what am I missing Confused.I have also experianced the issue of passing hpt and still having what appeared to be steam coming off the top of the processor, I even posted a what is this picture, and I still don't know where what looks like moisture comes from (it did not steam up cold glass),and it doesn't show up on the hpt Tom


In case you forgot, you were the first one to bring up that monoglycerides are hygroscopic in another thread (maybe inhaling a little too much acetyline today Big Grin).

This oil is literally from the sewer so it is heavily water soaked to begin with, I crack it with heat, then let settle, followed by purging off the oil layer into the reactor for drying and eventually HTAE. Not so much luck this last go around.

It passed HPT now 18 or so hours ago and is still pushing off steam. To put this in perspective I can usually dry in one day no problem, pass both HTP and fog test then give an extra hour dry time for good measure. This is definately H2O moisture coming off and will densley fog up a glass in a matter of seconds

The other thing might be the high concentration of animal fats holding water, but I have dealt with this before without the big issues I am seeing during this go around....(or so I thought...)

Anyway, the point is this might be one of the reasons that some guys on here are still having issues with AE. For example, I might have been having larger water contamination issues than I thought, but my mistakes could have been 'somewhat' covered up by the introduction of sodium bentonite absorbing the excess H2O.

My resluts have been fairly consistent, but not always as predicted compared to all past results. We should be able to nail down AE with a high level of predictability and as of yet we haven't (although great strides have been made!)

I think this is something that should be considered.
 
Location: Buckeye | Registered: July 07, 2009Reply With QuoteReport This Post
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Sorry Stormin, I didn't mean to hijack your thread...

I would guess anytime there is so little drop in T it is either a caustic or water contamination, are you using the same reactor for AE that you would for base? How do you test for water content in your oil?

I would go for a higher reaction temp as well, 135F is a bit low and can really slow down the reaction time.
 
Location: Buckeye | Registered: July 07, 2009Reply With QuoteReport This Post
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buckeye
-I said what! Big Grin Big Grin Now that you mention it, Rick Da Tech posted that on a thread not too long ago, if I said that I was repeating what I had read! hygo what Big Grin these words arn't in my day to day vocabulary, and yes I'm sure the acet didnt help.can't believe I forgot that, very disturbing Red Face
-I will check with US customs and see what issues there are if any about taking carbide over the border, it is none hazarous until you add water Big Grin If it's good to go, I'll mail it from Fargo ND on my next visit. 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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Ha, sounds good Tom, if you have an address in North Dakota I'll ship you a box of sodium bentonite! Big Grin

Hygroscopic just means a molecule or element that likes to 'mop up' water. Didn't we already cover this in the other AE discussion? Big Grin
Maybe I should let you keep the carbide, seems like it might cause temporary drain bramage! Big Grin
 
Location: Buckeye | Registered: July 07, 2009Reply With QuoteReport This Post



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buckeye
-LOL


" 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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[QUOTE]Originally posted by buckeyebiodiesel:
I would guess anytime there is so little drop in T it is either a caustic or water contamination, are you using the same reactor for AE that you would for base? How do you test for water content in your oil?QUOTE]

I use a BioPro 380. It drains completely, so there is no caustic, or anything else left in the tank. The water content was tested with a Sande Brae kit and was 350 ppm.

I can only guess that somebody used a caustic cleaner that I have not encountered before. I will continue to add small amounts of sulfuric and see if it can be overcome.

Norman
 
Location: Lincoln, NE | Registered: April 10, 2006Reply With QuoteReport This Post
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Norman
the caustic resadue is in the tank, lines and pump! even though the tank drains well, the caustic will be on all the wetted surfaces. you can prove this for yourself, neutralize the whole batch with sulfuric acid after the next base process, the following ae treatment will be different, like nite and day! 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 is correct, and the first on this site to discover this phenomenon, also 350ppm water is good, but lower will be better. What percentage sulfuric do you use?
 
Location: Buckeye | Registered: July 07, 2009Reply With QuoteReport This Post
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Tom--

The BioPro has no lines or pumps, for the WVO at least. Any caustic film that sticks to a vertical stainless steel wall is going to negligible at best. Besides I have probably done 50 acid batches in a Bio Pro and never has this issue before. I must assume the problem is in the feedstock.

Buckeye--

I use 93% sulfuric. Actually it varies from barrel to barrel when I buy it, I believe the last one I got was 95.2%. It is guaranteed at least 93% and that is what I sell it as. As far as water content I usually strive for 500ppm or less before I process. It is really easy to dry it in a BioPro, you just leave the lid off and stir it. If I have plenty of time I usually get it down to about 200. This time I needed some for a trip and won't havve it finished anyway. It did drop to about 4 titration this morning, so I added base and it is settling now. Appears to have some extra glycerin, but it will be as good as any other.

Thanks for the responses, another lesson learned.

Norman
 
Location: Lincoln, NE | Registered: April 10, 2006Reply With QuoteReport This Post
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That could be true that the contamination is in the oil and not from residual in the processor, and you have had many successful batches thus far, but many on this forum have found Biotoms observations on this matter to have an effect on T regardless. I would recommend you try his approach to dealing with AE when using the same reactor and I bet your results will improve and be even more consistent.

95.2% is good acid. Although many people on this forum use 93% I would suggest not using strentghs that low since the remainder is primarily H2O. Better results can be had with higher purity especially if dealing with very high titrating oil.

I use 95%/98% with excellent results. Water is the biggest enemy of AE once caustic is taken out of the picture, may as well do what we can to eliminate it and higher concentrations of acid.
 
Location: Buckeye | Registered: July 07, 2009Reply With QuoteReport This Post



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Norman
not to beat a dead horse Big Grin Big Grin but, I stumbled on the effect of residual caustic when I used my bone dry! steel methoxide tank to mix the acid into the methanol. the following ae process did not work, the acid was completely neutralized by the caustic resadue. When I take a T sample prior to ae, the sample has a ph of about 6.5 -6.7 after ae, ph .75 - 1 the T sample following ae only require 1/4 ml of caustic T solution to bring the ph back to 7 so from this you can see that a very small amout of caustic even if it is dry on the metal surfaces can have a real negative affect of the ae treatment. 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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quote:
Originally posted by Biotom:
Norman
not to beat a dead horse Big Grin Big Grin but...


Hell Biotom we've been whippin' this horse for some time now, she still has a few good lashes left in her Big Grin

Or in other words, Stormin, ditto on what Biotom is saying.
 
Location: Buckeye | Registered: July 07, 2009Reply With QuoteReport This Post
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