How to recharge DI resin

[wooden_reefer]

You're right. The cation resin in a softener is also different in that it is designed by be recharged with sodium, rather than an acid like the cation resin we use more commonly in our mixed bed resin.

Russ

I once worked for a water company in my college days.

They recharged a certain resin using an acid. I have always thought that it is the same resin as in water softener. Looks the same

I was then told that the resin in water softener can also be recharged using an acid, not just sodium ion.

 

[Mongor1]

Recharging resin resulted in different colors

Recharging resin resulted in different colors

Hello all, first of all thank you for this forum, it has saved me alot of money because of my cities water, my R.O. filter can only get the output down to 50ppm so I go thru alot of resin, this has saved me $$$$, thanks!

I had purchased 1.5 gallons of mixed resin from bulkreefsupply.com and have been using it for a few months now until it all needed to be recharged.

I followed the steps in the instructions (as I have done before with a different resin) and one really weird thing happened. The anion turned 'blue' as soon as I put in the lye? According to the instructions it is not supposed to turn blue, the cation is supposed to. It was separating and floating on the top, as it should, so I guessed it was anion for sure. Well, I pushed ahead and continued to the step to add acid to the cation and that is supposed to turn blue, and it did not? Is it possible this mixed bed DI resin has the color change reversed?

Thank you for any help,

Gary

 

[dngspot]

I have seen this before. It should not make a difference.

 

[fatdaddy]

Thanks for the instructions. I just processed 6 canisters worth. Good stuff.

On my second run through my lye mixture wasn't strong enough, so the resins didn't separate properly. I just mixed up another stronger batch and all is well.

btw, I just used a glass pitcher (walmart $7) to pour off the resin on the top. It takes about 20 seconds.

Re: safety equipment - I don't like gloves because if anything spills down your sleeves, it usually burns before you (I) notice. I just very careful and rinse my hands after every operation. Perhaps if I could get some arm length gloves, I'd change my mind.

 

[fatdaddy]

On second thought, I think I'll just separate the resin and run it in separate chambers. That way, I can just regenerate by running acid/base through the chamber and rinse with RO water. All I'd need is a Ph test to see when the resin is flushed sufficiently.

Question: Does anybody know what concentrations (Ph) that I'd need to recharge the resin?

 

[PurdueWaterGuy]

The cation exchange resin in the typical water softener is called sodium cycle resin, and is regenerated with a 10% (more or less) NaCl solution

The cation exchange resin which makes up half of a DI cartridge is called hydrogen cycle resin, and is typically regenerated with (don't remember the concentration off the top of my head) hydrochloric acid, HCL. Muriatic acid is low-grade HCl.

You would get a better regeneration of your resins (and longer lifetimes) if you separated the anion and cation resins before you apply the regenerants. Typically this is done by putting the resin in a column, flowing water up thru the resin, and letting the two "flavors" separate by density.

Call me a wuss, but I'm still not sure I'd do this at home - if you are going to do it, at least use gloves and a face shield and do it in the bathroom so you can get in the shower if need be. And yes, I work with larger volumes of stuff like hydroflouric acid that makes muriatic acid look like Tang.

I'll be glad to offer up info to help, but let's talk about some safety issues first.

Who am I? I'm sort of a professional water geek. There's 90 cubic feet of LTOC grade (better than nuclear grade) ion exchange resin in my system at work. We don't even regenerate our resin, we sell it to someone with much lower standards.

Tim

 

[PurdueWaterGuy]

This is for yardboy if he's still tracking this thread: Nice System!

Now it's my turn. My system:

two 12 cubic foot water softeners in series.
Three 9" KDF filters in parallell to strip chlorine.
Two-pass RO, 66% recovery, 20 BW30-4040 membranes, 19,000 GPD
3000 gallon storage tank, PVDF lined, Nitrogen blanket, .33 ppm ozone. All plumbing past this point is PVDF or stainless steel
20 gpm pump
Dual wavelength high-energy UV to kill ozone
3 pass Liqui-Cel degas membranes, combo mode (Vacuum + high purity N2 sweep)
2 E-Cell electrodeionization units in parallel
two 15 cubic foot mixed beds filled with Resintec LTOC resin
.45 micron filters
water goes back to the 3000 gallon tank, unless it needs to top of the pair of 2200 gallon tanks
two 2200 gallon tanks, PVDF lined, high purity nitrogen blanket, .033 ppm ozone
100 gpm pump
dual wavelength high energy UV to kill the ozone
three pass Liqui-cell degas membranes in sweep mode
two 30 cubic foot mixed beds, more Resintec LTOC resin
.45 micron filters
another 100 gpm pump
pair of ultrafilters, 6000 Dalton cutoff
Heat exchanger
system then feeds 22,000 square feet of clean room, and I forget how many square feet of lab space.
Back to the 2200 gallon tanks.

Our TOC level is typically below 200 PPT, Boron is typically below the detection limit of 15 ppt. Most semiconductor fabs are happy to get below 1 ppb of TOC. We only use virgin resin, what comes out of our system gets sold to people with less stringent standards.

Glad to meet another water professional!

Tim


How the heck do you insert pictures?

 

[dngspot]

I recently visited with CathyJ from salt-city.org . She explained that she now regenerating large batches of resin and explained how she did it. This is one of the greatest things about forums is one can take an idea and make it better or customize it for them selves. It involved a 5 gallon water bottle, 1/2 inch bulkhead, 1/2 npt nipple, and a ball valve. I also used a 1/2 pipe to barbed fitting to slow flow a bit. For the stand I made it from 1 inch square tubing, it is 36 inches tall and will allow for the tallest bucket I have to fit under it. The idea to do the larger batches is to multiply the directions from this thread.
The reason I need to do larger batches is because I bought a 20"X4.5 canister from Bulkeyefieldsupply.com and the darn thing holds about 8.5 pounds of resin. The most I can do with my smaller setup is about 3 pounds.
Here is a pic.

 

[wilsonreefs]

Why does anyone do anything? A lot of times I do things just to see how it's done. I have always wanted to know how to recharge this stuff. Even googled it (didn't find out how until now). I found this really interesting and now that I have a guideline to go by, I'm sure I'll have to try it. To save money?, no, just to see if I can do it.....and I too hate to throw away anything I think I can fix and reuse..

 

[shikhyung]

Do you have a full set up for this new system? Thanks

 

[shikhyung]

never mind, I kind of skip reading between breaktime. But I have question, I use BRS color-change resin , it kinds of blue and clear brown ( when new), looks different from the pics ( all brown). Can I do the same process?

 

[Buckeye Hydro]

Yes. Different manufacturer/resin = different color.

 

[shikhyung]

Thanks Russ.
1-I read the instruction with pics in previous page. wonder why put the cation in the ziplock bag after rinse with water then after dumped out into a jar then add acid. Is there a reason?
2-with the solution mixed 12 ozs of lye, is good for a batch of how many pounds of resin?

 

[dngspot]

I put the cation in a zip lock because it is easier to remove it from the filtering cloth. The jar has a smaller opening and I cannot fit the resin and filter in it.

6 oz of lye with 24 oz of water is enough to separate the anion and cation, from 2 10 x 2.5 canisters. Each canister holds about 1.25 lbs of resin

 

[shikhyung]

thanks, dngspot. BTW, is there a way that you can tell that the recharge resin is good or bad.
Or the only way is to put them in the system.

 

[dngspot]

I cannot answer that, each time I separate and recharge, I load the canister and look at the tds gauge. It always drops to 0.

 

[dtaranath]

haha great thread. just regenerated my resin, thanks!

In order to save even more time, does anyone premix their lye so that when it comes time to regenerate, the lye solution is ready to go, not needing any further cooling? It seems keeping a gallon of the premixed lye solution would save time.

 

[dngspot]

I have not stored premixed lye. I did not clean my containers once and the lye residue ate through the bottom of the container. Lye also looses its potency when co2 comes into contact. If you try this keep that in mind. Over all I think this may be a bad idea.
Good luck

 

[grinner30]

Great Thread and instructions! I will be attempting this this weekend and I am sorry I dumped so much resin out over the last couple of years...:hmm3:

 

[SpectraPure]

Nice system. Brings back memories for me. Used to run an APIMS for the ppt stuff, but I was mostly a ultrapure "gas" guy trapped in the wet clean area at that time of my life.
Nice post!

This is for yardboy if he's still tracking this thread: Nice System!

Now it's my turn. My system:

two 12 cubic foot water softeners in series.
Three 9" KDF filters in parallell to strip chlorine.
Two-pass RO, 66% recovery, 20 BW30-4040 membranes, 19,000 GPD
3000 gallon storage tank, PVDF lined, Nitrogen blanket, .33 ppm ozone. All plumbing past this point is PVDF or stainless steel
20 gpm pump
Dual wavelength high-energy UV to kill ozone
3 pass Liqui-Cel degas membranes, combo mode (Vacuum + high purity N2 sweep)
2 E-Cell electrodeionization units in parallel
two 15 cubic foot mixed beds filled with Resintec LTOC resin
.45 micron filters
water goes back to the 3000 gallon tank, unless it needs to top of the pair of 2200 gallon tanks
two 2200 gallon tanks, PVDF lined, high purity nitrogen blanket, .033 ppm ozone
100 gpm pump
dual wavelength high energy UV to kill the ozone
three pass Liqui-cell degas membranes in sweep mode
two 30 cubic foot mixed beds, more Resintec LTOC resin
.45 micron filters
another 100 gpm pump
pair of ultrafilters, 6000 Dalton cutoff
Heat exchanger
system then feeds 22,000 square feet of clean room, and I forget how many square feet of lab space.
Back to the 2200 gallon tanks.

Our TOC level is typically below 200 PPT, Boron is typically below the detection limit of 15 ppt. Most semiconductor fabs are happy to get below 1 ppb of TOC. We only use virgin resin, what comes out of our system gets sold to people with less stringent standards.

Glad to meet another water professional!

Tim


How the heck do you insert pictures?