Also, there's a new Thermax page on my site...
GCG & Chad helped put it together.
It details a bunch of what they've mentioned here..
The other dry resins we know take out water, remainings of methanol and glycerol and exchange Na+ for H+ and yield excellent quality biodiesel. I trust Thermax does that too. That's an advantage of using a dry resin.
If we would regenerate a intially dry resin without drying it again, what point is there in using a dry resin in the first place? Why not buy a much cheaper wet resin and safe up to 80% costs? No volume expansion to worry about either.
Hey GCG, sorry about that, I just couldnt resist myself pokin a little fun at Ant. Does this require the same mesh size as other resins? It kinda looks a little larger in diameter?
If it aint broke, dont fix it! But its ok to take it apart and see how it operates.
I am always impressed by your questions and comments - I also have thought that Sulfonic acid would or is the logical choice for regeneration however all the references I have seen so far refer to Sulfuric Acid. Here is the direct info from Dow Corporations Regeneration info:
"Sulfuric Acid (H2SO4):
Sulfuric acid solutions are mostly diluted to 1 to 6 percent for the regeneration of strongly
acidic ion exchangers and to 0.5 to 1 percent for weakly acidic ion exchangers in water
Generally I have heard it put that a "mineral acid" is required for regeneration of a highly acidic cation resin which is derived from inorganic compound vs. an organic compound like Sulfonic acid. However the ground between them is only one Oxygen atom:
And Sulfuric acid if it undergoes an "Electophilic Aromatic Substitution" (say that 3 times fast) turns into Sulfonic acid. Who knows exactly what is going on at an atomic level anyway???
Acids and Bases used to be easily defined as either a proton donator or proton acceptor but that modality has been brought into question by modern chemistry.
The main point here though is some acid will be added for the regeneration of the resin and this full methodology will be provided to the customer.
As to the matter of purchasing dry resin vs. wet resin.
Technically speaking "dry" in the resin world isn't exactly what it means to us generally - dry is defined as less than some small quantity of moisture still retained in the bead after production particularly in the case of the gel-type resins used in biodiesel purification like PD206 and BD10 Dry. They actually do have some moisture in them but the term is used in comparison to "wet" resins which hold some amount above this minimum hydration mentioned (I can't remember the exact number).
Anyway even the so called wet resins don't actually feel wet but our slightly heavier and do feel slightly different from say a dry gel resin (but not much to the touch).
This moisture still in the gel-resins is actually what is responsible for the internal ion exchange sites to be taken advantage of. In actual molecular action or movement the thin layer of crude biodiesel which coats the surface of the bead is called an interstitial layer and a transfer of impurities occurs between this interstitial coating and the fluid in the beads.
The best analogy I can draw is that this is similar to how a mother transfers oxygen and nutrients to a fetus through the umbilical cord. There is no real exchange of blood but only the nutrients pass through the membrane which divides the two inside the umbilical cord.
This is why it is possible for a child to have a different blood type from that of the mother, with out the mothers body rejecting it like an incompatible organ.
For me the advantage of a "dry" resin is that it won't contaminate the initial biodiesel purified, by releasing water or other substances when they are displaced either by methanol or glycerin as they are adsorbed.
So after the whole resin bed has undergone its first flush with methanol (removing glycerin, entrapped soap and other impurities trapped by glycerin), the excess methanol which is not trapped in the beads is flushed out by a few bed volumes of biodiesel. Some methanol, though, will still be trapped in the beads and this methanol continues to act as that transfer agent until it is displaced by glycerin again in the next cycle.
Incidentally this is another reason why I believe the macroporous resin is superior since in the gel bead as glycerin displaces methanol that area of the bead is not as available for continued ion exchange where as the macroporous bead doesn't fully rely on this methanol agent for ion exchange since due to the macro-channels - the long chain hydrocarbons can deliver the impurities themselves to the interior portion of the bead. However this conjecture on my part would probably be debated by the Phd's...
The only products being used in the North American market are narrow particle size resins such as BD-10, PD-206, T45 BD Macro. These products have all had the “fines” removed in order to minimize pressure drop concerns . The mean particle size for Tulsion Macroporous resin is 600µ +/- 50 µ.
The density of the beads is very different between the macroporous and the gel-type resins with BD10 Dry at approx. 830 g/l while the bulk density of the T45 BD MP is ~475 g/l. The difference is due to the large porosity of the bead.
Well an important difference is that Sulphonic acid is much stronger than Sulfuric acid. I don't have to tell you that sulphonic acid catalysts are used in esterification (not necessarily biodiesel) for that reason. Now unless the resin has been sulphonated with sulfuric acid, we can assume it has been sulphonated with sulphonic acid.
I agree with you that sulfuric acid is used to regenerate many resins. But how efficient is it in this case?
I can assure you that a resin manufacturer knows very well how to regenerate a resin. So it shouldn't be something that we ask ourselves here, it should be answered by the manufacturer right away. Thermax introduced themselves two months ago here, I still wait for some answers.
I am sure that it is an excellent company, but they are probably tied up with market introductions right now so answers arrive late.
Now a dry resin will clean out water, methanol, glycerol and exchange cations for H+.
If you just flush it, it will only be good to take out glycerol so it can be used to shorten settle time (but contaminate your biodiesel with more methanol as well). We can agree on that.
If you regenerate it without drying it, the resin will remove soaps, glycerol, but being 'wet' with methanol, it's unlikely that it will remove any methanol.
And removing the last bits of methanol down to spec is one of the major advantages of dry resin.
If you would regenerate this or any other dry resin without drying out the methanol, you could as well have taken a 'wet' resin, rinse it with methanol and use it the same way. Cationic resins plenty out there.
So I'm not saying a wet resin is the same as a dry resin which hasn't been dried, I'm saying that from a user's perspective, it doesn't matter if you use a partly regenerated but not dried dry resin, or a partly regenerated wet resin. In both cases the resin won't remove methanol.
So unless you really dry a wet resin, you don't really regenerate it.
So again, if I step into home-regeneration of resin, why would I buy a dry cationic resin if a wet cationic resin gives me the same performance (macroporous resins plenty there) at a lower price? The only difference would be the first use of the dry resin - where it also would remove methanol.
Or am I missing something and does the Thermax resin not remove methanol at all because of it's macroporosity? How large are the pores?
Ok, not so sure that I am on the same page here as you. What I am asking is the mesh size of screen needed in a tower application to keep the resin in place. (Example)Purolite recommends a screen size no greater than 150 micron, is this the same or is a larger or smaller screen needed?
If it aint broke, dont fix it! But its ok to take it apart and see how it operates.
You can use the same size mesh screen to act as the resin support or barrier. The manufacturer recommends the same for both.
Dimitri (this turns out to be a kind of 2-part answer so hang with me),
I understand your point. It definitely would be best to dry the resin fully if you had this capability - we have a Chromalox air heating unit that we intend to set up for this purpose however we have not actually performed this operation yet.
The idea here would be to drain the column of all methanol after it has been fully flushed and then backflow either hot air or nitrogen through the column and then through a condenser to reclaim any methanol driven off. This procedure would continue until no further methanol was condensing out and being removed.
Going further we just completed a methanol flush flowed by a biodiesel flush of the macroporous resin so I will get a sample and see what the present methanol content is coming directly out of the column.
Also not everyone will have the ability to do this kind of operation so we've been thinking it may not be necessary since
we send biodiesel to a lead/lag set up which has had methanol removed down to ~0.2%.
Our lead/lag set up utilizes a first bed of macroporous resin and a second bed of gel-type resin. In my mind what this does - is allow the macroporous resin to do the large bulk of the purification work (which it is very well suited for since it is a very robust bead and can undergo many flushes and regenerations with little losses), then let the second column acting as a polisher.
The macroporous resin when initially used will do the whole job of purification until it gets about 80% used up then it is possible for slippage to occur (I believe this percentage is also dependent on other factors with the largest one being the percent methanol in the biodiesel being passed through the column - based on our experience it is the same with the gel resins). Whenever this slippage of contaminates begins to make it through the column there is still unused capacity so the second column now picks up the small amount of slippage.
In the case of macroporous resin it will not remove as much methanol as the gel resin and it will not remove as much glycerin as the gel resin, however the macro resin can do its job at methanol levels which are at ASTM where the gel resins really require methanol of at least 2% to work properly (J. Van Gerpen's work showed this in his paper: Soap Removal using "Waterless Wash" methods.).
At ASTM levels of methanol the biodiesel will contain only the minimal amount of dissolved glycerin/soaps, so the resin is performing at the level it is designed to operate at and removing levels of impurities that provide for the most economical use of an ion exchange resin.
It's a balancing act! The gel resin was promoted by Rohm&Hass in North America because they saw it as a simple product to sell to biodiesel producers that filled a cumbersome need and also ensured repeat sales since the higher levels of methanol (1.5-3%) would contain fairly sizable levels of glycerin. Soap production for the large commercial producers wasn't going to be that big of an issue, since virgin oils were going to be the feedstock of choice.
This has changed drastically for a large portion of commercial producers and it has never been the case for the small and micro-producers using used cooking oils (since these oils contain FFA's and produce significant levels of soap).
If a small or home biodiesel maker runs biodiesel with both dissolved glycerin and soaps at the levels contained in this 2% methanol, it eats ion exchange resin up rapidly.
Now some people don't care about this added cost (passing it on to the customer or absorbing it) Some producers just don't want to deal with water washing and the time involved. They just want to keep on pumping through to finished product.
What I'm saying is, use the best product, for the right job, using the right process.
So to finish up this part:
1) After you flush with methanol, you flush with biodiesel and as you said this biodiesel will contain methanol and will need to be demethylated again (if you demethylated it prior to sending it to the resin bed as I recommend).
2) Then the biodiesel sent through after this shouldn't contain >ASTM levels of methanol (since only trace amounts should be trapped in the resin), however if it does, these small levels above ASTM will be removed by the polishing bed of the gel resin. This way the gel resin can last a very very very long time while the macro gets flushed and regenerated numerous times.
Lastly, there are other macroporous and wet resins out there (like the GF202 from Lewatit) but I am unsure of their cost and their performance as a biodiesel purifier.
I can tell you from our experience when originally working with Thermax on this resin, we were far from satisfied. The standard macroporous resin contained excessive color bodies and needed additional processing in order to make it appropriate for sale in the biodiesel purification market - this step did cost money. Also this Thermax Tulsion macroporous resin is a co-polymer highly cross-linked formula and is one of the most expensive to manufacture.
On Second review of your post - at the end you ask for the pore size of the T45 BD MP:
Average pore diameter is 400 angstroms with each bead having ~30% porosity which yields an amazing total surface area per gram of material of 35 square meters...
A 300A Relite from Mitsubishi has an incredible 50 m2/g surface area.
I'm sure the Thermax resin is an excellent product, but is it so much better than other resins out there?
If not, we should officially introduce a few others of them as well.
I'm not sure if you're bating me or not, but I am not at all opposed to this thread or another thread becoming an all out inquiry to find/discover the absolute perfect biodiesel purification product or products out there.
The world is a big place, with a lot of technological innovations occurring everyday so which Relite (Resindion by Mitishubishi)is it since my quick google search didn't turn up a:
3) Hydrogen form
4) Strongly Acid Cation
Ion Exchange Resin (Is this resin readily available in North America? Do yo know its percent of porosity?).
Lastly I can only speak about and introduce a product which Arbor Biofuels Company has worked with and are very impressed by.
One of the leading experts in the world of biodiesel is running Thermax Tulsion T45 BD MP through a battery of test currently - and thus far (from what I hear) has very positive things to say about it.
I am very excited to have the privilege and opportunity to introduce another choice for biodiesel producers. To share our positive experiences while working with it and engage in lively and thought provoking discussions like the ones you so often a source of.
The YouTube video was removed. Is there a different one?
Edit: found it here: http://www.youtube.com/watch?v=6nMsqTujGWI
Sorry, I kept updating it (fixing typo's, redoing the transitions, stuff like that) to make it better.
I think I'm done on it though.
Chad & GCG will do a couple more on different topics on the towers & Thermax later on & we'll post those as well.
Hope everyone is enjoying them.
Hey just a note to all the people who have requested samples. You should have received your sample by now!!! If however you have not please let me know through a PM and we will get it out ASAP.
We had one person PM us today so I'm just checking on everyone else -- Thanks
If you've sent any to Canada give it extra time as Customs here is quite anal and with Christmas coming all the new trainees will be trying to make a name for themselves.
** Biodiesel Glycerine Soap - The Guide
- on 5 continents helping people make & sell soap from the Biodiesel Glycerine.
GCG , Just to let you know I got mine yesterday, when I got back from Reno it was here.
Technical point: you failed to differentiate between "Sulfonic Acid", the chemical, and "Sulfonic Acids", the class of acids with the general formula RSO3H(ignore the periods; this site does not accept HTML spacing codes):
Further note that any aromatic substitution would involve an aromatic group (benzene ring). Your source, Wikipedia, includes this image as an example of the EAS reaction:
"Political language... is designed to make lies sound truthful and murder respectable, and to give an appearance of solidity to pure wind."