Jeff
You should try our Macropourus resin in your set up we're told that you can get 300 gallons per pound of resin, We haven't ran that much through our setup yet to confirm those numbers our selves.
Our small set up is 20lbs in each column, so we're hoping to achieve 12000 gallons before any change out.

If your interested in using resin for purifying biodiesel here are the latest GC lab results from our macroporous resin.

ABC resin purification GC results

A pictures worth a thousand words. Now that is some sparkling biodiesel...

GCG

Jeff; do you put the biodiesel in thru the tube that goes to the bottom of the tank or does it come out the tube?

greaseman,
the clean, soap-free b/d exits the vessel from the tube at the bottom

We use amberlite. Watch the soap#'s, hi soap will raise the TAN# throwing your fuel out of spec. We had some promising results using sulphuric & methanol to regenerate the amberlite. We have had some setbacks & are just collecting UVO until our new facility comes on line.

Garthh

Right on Garth!

Do you mind sharing your set-backs because believe you me - we've had our share; if its not one thing its another...

GCG

GCG,

What do you find to be the "best" mix for a 2 column system? A combination like Macropourous in lead, PD206 in lag? Straight Macropourous in both? What do you think would be best (and do you have any data that helps to push you in that direction)?

Thanks,
-Scott

hc,

Yes, I believe if you are a larger producer of biodiesel and its important for you to meet ASTM fuel standards then a lead and lag column system utilizing a type macroporous (i.e. Macro-BioPure) resin first and the gel-type (i.e. PD206) second is the most cost effective set-up.

This assumes that the resin is used in the range of solubility for its impurities and that the user intends to flush out adsorbed glycerin on the lead resin bed numerous times. The Lag bed of PD206 would last for a very very long time...

GCG

OK, so here are some for 30 bucks. Should I go for it? Is everyone reasonably convinced this will work if I use a lead with mocroporous and a lag with purolite or amberlite?

quote:

This assumes that the resin is used in the range of solubility for its impurities and that the user intends to flush out adsorbed glycerin on the lead resin bed numerous times. The Lag bed of PD206 would last for a very very long time...

What the heck does that mean and how do I measure it?
- Chris

Chris,
Thats the tanks I use with the lead-lag setup.
(macro-lead pd206 lag). So far its working well.
I have only run about 100 gallons or so thru it.
I put approximately 12 lbs of resin in each. Run them at about 4 gallons an hour.

Chris,

Check out this for how I explain things.

My understanding of what GCG is saying is that the contaminates need to be dissolved in the biodiesel. If the biodiesel is cloudy or turbid, then something is not dissolved, so were looking for clear bio that you can read newsprint through.

quote:

Originally posted by RickDaTech:
Chris,
Check out this for how I explain things.
My understanding of what GCG is saying is that the contaminates need to be dissolved in the biodiesel. If the biodiesel is cloudy or turbid, then something is not dissolved, so were looking for clear bio that you can read newsprint through.

Thanks for the responses.

Rick,
That is an excellent link, thank you. I like the simple colored diagrams like that because it is sometimes difficult for me to decipher the maze of tubes and wires and valves from people's pictures.
I've read before that free floating soap and whatnot will indeed clog up the beads - and intuitively that makes sense.
However, I'm confused by these two statements in the explanation:

quote:

Start with biodiesel which has had the methanol already removed.

VS this a bit further down:

quote:

The resin depends on methanol being present to act as a solvent for the soap. If the soap is not completely dissolved in the biodiesel, it will tend to clog up the resin.

quote:

It is recommended the brew sits for 4 weeks before being sent through the beads.

This is a heck of a long lead time. Any way to shorten that up?

I was thinking of building a Plumbers Delight recovery system.....but not yet. Some people have suggested doing a water wash beforehand which would sort of defeat the purpose. I also note that some folks such as Legal Eagle are not scrubbing methanol prior to dry wash with the understanding the beads may not hold up as long. But, then I read at the bottom of the page in the "comments" section that methanol is used to recharge the beads. What the heck?

- Chris

Chris,

There are no hard and fast rules with these resins. If you remove most of the methanol before passing over the beads. most of the soap will drop out and extend the life of your resin. However there needs to be some methanol left in it to act as a solvent. That's not really a problem with the GL method as it is a little difficult to get ALL the methanol out anyway.

You can shorten up the settling time, my guess is that as long as the bio is clear and not turbid, it will do just fine. The 4 week figure comes from Jeff who started this thread.

In the comments Bill was talking about a typo in the first section where I discussed the types of resins. That's been addressed already. But yes, if you have a fouling problem, passing methanol through the beads will clean them up and make it usable again. Also, if the beads pick up any free glycerin then yes methanol will wash the free glycerin off and give you some more life. That's with Amberlite and Purolite.

The Lewatit is a special case as GCG keeps pointing out. To be honest, I'm starting to think that it's the only resin suitable for homebrewers.

Chris,

I think 4 weeks is a very long time to wait for the BD to settle. Once the methanol has been driven out, the soap will drop out within a few days -- maximum one week.

I think GCG says 72 hours before introducing it to the resin columns.

Now from my experience which is limited, I let the BD settle for about 2 weeks. I have 4 drums to allow batches to settle out and I pull from the oldest barrel of BD. If you go balls to the wall and make a batch every other day for one week, you have a backlog for future use and you can reduce your production to once a week after that. Filtration will be an ongoing process as you need the fuel. Or you can accumulate filtered fuel.

The magic bullet is in your gun. :-)

Rick,

That site is fantastic!

Just a long note on resins - the Lewatit product is generally sold in its Sodium form (Na+ form) vs. the Hydrogen form (H+ form).

The difference is important since the sodium form resin removes glycerin by entrapment and removes soap by removing entrapping the glycerin. So the resin acts like a sponge for glycerin and the glycerin acts like a glue for the removal of the soaps.

On-the-other hand the H+ form resins (which the PD206 and BD10dry are as well as our Macro-BioPure)can remove soap the same way but also remove soap by exchanging the Na+ or K+ atom attached to the FFA chain (which is what soap is) for a H+ atom. The Metal atom (either Na+ or K+) is bound to the resin bead while the FFA chain passes through...

Additionally the GF-202 is usually shipped "wet". This means it requires a thorough pretreatment prior to biodiesel purification.

As to whether excess methanol is required for ion exchange columns to work properly or not and what is the "level of solubility?"

The reason washing is done to biodiesel is to remove excess methanol, glycerins and soaps. If washing with water, the water won't mix with the biodiesel easily and so settles out of the biodiesel. However it does mix with the methanol readily. This strong affinity for each other is referred to as: miscibility.

Water and methanol are 100% miscible chemically. Methanol is an excellent solvent and the residual soap and glycerin remaining in the biodiesel, after settling, resides nearly 100% in the methanol. Therefore when water is mixed with biodiesel and allowed to settle out, it takes all the impurities with it.

This leaves you purified biodiesel, albeit a little bit watery still, so then you dry the biodiesel to remove the residual water left from the washing.

Ok now, with ion exchange the idea is avoid mixing water into the biodiesel and therefore avoid the long washing phases and this final drying phase.

What people realized was that certain ion exchange resins seemed a perfect idea since many were methanol tolerant and the quantities of methanol still in the biodiesel after settling would facilitate the easy flow and interaction with the resin beds - perfect - NOT quite!

Why?

Because when home brewers make biodiesel, they do it with used cooking oils with high Free Fatty acids (as compared to industrial producers who use virgin oils with almost no FFA's).

These FFA's when exposed to the catalyst immediately saponify (turn into SOAP). These soaps then find their way into the excess methanol right along with a portion of the glycerin produced in the biodiesel reaction.

Subsequently the excess methanol which remains in the biodiesel after the gross glycerin removal is the carrier for all the remaining impurities - AND THERE IS A LOT OF THEM (relative to the resins ability to remove them cost effectively).

We have found that after removing methanol to near ASTM levels (say 0.08% to 0.2%) and then allowing the biodiesel to settle 72 hours the soap levels are <300 ppm. Dissolved glycerin levels are say <200 ppm.

If we don't remove the methanol then our soap levels run about 2500 ppm (please note that are initial oil is only 1% FFA by weight to begin with and this greatly reduces the total soap content. For example if the starting point were 2% then I would expect 5000 ppm soap content prior to demethylation).

These numbers are important because the resin is designed to work economically at the 500 ppm total impurities level (since it is designed to work on only those impurities which remain in solution or dissolved - this is the "level of solubility")

Unfortunately methanol, since it is a strong solvent, it raises the level of solubility greatly and so it holds significantly more impurities.

If you have an impurity concentration of 2500 ppm then it will exhaust the resin 5 times faster than it is supposed to and therefore raising the cost of that resins use 5 times.

Right now, we get about 150 gallons of biodiesel purified per lb of our Macro-BioPure resin. This resin cost ~$7.00/lb and so this yields a cost of ~ 5 cents per gallon of purified biodiesel. If we left the methanol in then the cost would be 25 cents per gallon and we would have to change out the resin 5 times as often.

That's the trade off!

GCG

This message has been edited. Last edited by: GCG,

Oh yeah!

The beauty of not removing the methanol prior to resin purification is you can go right from a 1 hour settling time or right from a centrifuge to the purification step.

And then when you do the rapid removal of methanol , since there is no glycerin, soap or catalyst, there is no chance of reverse reaction and no slimy soap to settle out for 72 hours.

Note also that we do cheat this 72 hours often to <36 hours since by around this time the soap content is often about 600 ppm and we feel that is close enough.

Also the PD206, BD10Dry and our Macro-BioPure require very little pretreatment prior to use unlike the Na+ form resins which are shipped wet.

GCG

So the GF202 is Na+ and the GF201 is H+??

They ship the Na+ form wet?

Talked with Lanxess about this. The GF201 is being phased out in favor of the GF202. The only real difference between them is bead size. They are the Na+ form and shipped wet.

The straight poop:

1) The Lewatit GF 202 does not expand, meaning no compaction issues. (Can be slimed or fouled like all the others)

2) The Lewatit GF 202 can be regenerated completely with methanol, extending it's working life many years.

3) Lanxess recommends removing the methanol to levels below 0.1% and soap content to be below 500ppm

4) The biodiesel should be at 40C or 100F when passing over the beads.

5) Pretreatment consists of flushing the bed with methanol (5 bed volumes).

To put it in a cost perspective, the smallest container is a 25 liter bag costing $250-$300 and will fill two of Jeff's soda kegs with each keg holding 12 liters of beads. Recommended flow rate is between 18 and 24 liters per hour for each keg.

That compares to a maximum of 12 liters per hour for each of Jeff's soda kegs holding Amberlite or Purolite. Typical cost for 20lbs of Amberlite or Purolite is about $200.


So for a two keg system, it costs $50 to $100 more than the gel resins, flows faster, can be regenerated for up to five years, and does not have compaction issues.

And the straight dope: confirms everything I've been saying - Yeah!

Now that is the Lewatit/Bayer/Lanxess (which everone you want to call them) GF202 macroporous resin but not all macroporous resins are the same and our Macro-BioPure is neither Na+ or in a "wet" form and so is pretty much ready to use for biodiesel production when you get it!

Still has the other same benefits: not prone to compaction, can be regenerated too numerous of times to count and doesn't expand nearly as much as the gel-type resins.

Lastly the H+ form resin will convert over time to the Na+ form, since it is exchanging the H+ ions for the Na+ ion of the soap molecule. The beauty of this, is that by this time the resin is starting to load with glycerin and will now entrap soaps to give that resin bed an extended use - prior to being exhausted (or excessive pass through of soap).

But at this point the pass through should be handled by the lag column of PD206 and this why we are such a strong proponent of using this combination.

Keep in mind our Macro-BioPure is the same cost effectively as the gel-type resin and from our website its actually cheaper since the PD206 has more shipping cost due to our shipping rates from Purolite...(PS side by side comparisons indicate a longer life out of the Macro as well).

GCG