Regenerating GFO
 

In the thread about BioPellets jptenklooster posted this interesting tip:

"However, it will take longer before you have to replace or regenerate your killer (regeneration can be done with 1M NaOH solution, good tip to save some money)."

If you have tried this method, let us know how well it worked :thumbsup:

(I have had 3 kg of GFO in 1M NaOH 4 days now. JP told me to let it sit for one week.)

I've not tried sodium hydroxide, but it doesn't surprise me as even salt water can displace the phosphate, IME. It may take a fair amount of water, however.

I'm interested to see how well it works for you. :)

Just as a follow up, the iron in GFO (Fe+++) becomes more and more soluble as the pH rises from pH 8 to higher values. 1 M NaOH is about pH 14. At that pH, the amount of iron that dissolves (as Fe(OH)4- ) is just under 0.1 mM (about 5 ppm). So you will be dissolving away some of the surface. That may be beneficial for this process. :)

Randy,

Thanks :thumbsup:

Interesting information. I was just wondering if you could tell from the pH how the regeneration is progressing? Once the pH stabilizes there's no more loss of OH- ?

In my case the pH is now ~12.96. I'll check it again tomorrow.

My expectation is that the pH won't reliably change unless there is a lot of solid and almost no liquid. A pH drop could also be coming from CO2 entering from the air. :)

Damn! :lol:

Is the water becoming discolored?

Yes, it is getting slightly yellow. The pH has dropped to 12.60 (I don't know how accurate that is, the meter was calibrated couple of weeks ago @ 7.0 and 9.0)

If you wanted to, you might be able to track the process by measuring phosphate in the fluid, assuming the kit can handle the high pH. If not, you can always acidify it. :)

Your wish is my command!

Acidified the sample to pH 7.5, phosphate off the charts :) I didn't try to determine the exact amount (1:9 dilution was still off the charts).

Cool test tatu :)

Great tip. Just one question for chemistry handicaped ;) what is 1 M? How much quantity of NaOH we need to use? Disolved in fresh water? Or I get that completly wrong?

Dissolve 40 grams of anhydrous sodium hydroxide in 1 liter of fresh water. :)

Thank you very much Randy

:thumbsup:

Let us know what you find. :)

Blue

Look at the periodic chart here
http://academic.greensboroday.org/~r...odic-table.GIF

Now look for Na, O and H Molecular weight

Na = 22.99 grams = 1 mol

O = 16 grams = 1 mol

H = 1.08 grams = 1mol

NaOH has 1 Na, 1 O and 1 H

So, 1 mol of each = 1 mol of NaOH

So, 22.9 + 16 + 1.08 = 38.98 grams = 1 mol of NaOH or ~40 grams = 40,000 ppm

0.1 mol would equal = 4 grams= 4,000 ppm. 1 mmol = 0.04 grams = 40 ppm

If it was 1 mol of CaCO3, has 1 Ca, 1 C and 3 O

~ 40 + ~12 + (3 x 16) = 100 grams = 1000,000 ppm of CaCO3 = 1 mol

mmol times Molecular weight = ppm

and

ppm / Molecular weight = mmol


NSW has 10.27 mmol (0.01027 mol) of Ca++. So, 10.27 x 40 = 411 ppm or 411 ppm x 1.023 d = 420 mg/ l Ca++ .
NSW has 411 ppm / 40 molecular weight of Ca = 10.27 mmol




You do not use things like mg/ l or ppm for solving equations in chem but mol or mmol

Ummm, he just did something with math. I'm gonna lay down till my head stops hurting!

Who's afraid of the big bad Boomer?

I always thought 1 mole = 6 shrews.


Well anyway, this is very interesting. One of my personal goals is to keep phosphate as low as possible without lots of expenditure (VSV dosing to the rescue) but this is great news.

I'll be following along. Thanks Taatu

:rollface::rollface::rollface::rollface:



Red

That depends on the size of the shrew or species of Shrew vs species or size of the Mole :) Now, if we are talking about Pigmy Screws vs Water Screws, then...................................................









































































edit: Deleted, non-reef related subject, Randy Holmes Farley,11/05/09, 10:13 PM

How's the test going?? or did the GFO disentegrate,,lol..

Bob,

I'm going to let it sit one more day as recommended by JP. Next time I will try to track the regeneration progress more closely to get better understanding of the time required for the soak.

And no, the GFO is not disintegrating :D

Thanks for the update.. I'll be following this thread even though I use strontium nitrate for my phosphate reduction..

edit: Deleted, non-reef related subject, Randy Holmes Farley,11/05/09, 10:13 PM ]

Hey, I was asleep by 10:15 pm lats night. :D

You were probably walking in your sleep again :)

Tatu,

Do you think bleach (sod. hypochlorite) would work? Or perhaps pool chlorine powder (calcium hypochlorite)?



I'm a cabinet maker and I've heard of, and used, a lot of different types of screws. But I can honestly say I've never heard of a pygmy screw or a water screw. Are these phillips head, torx, or flat-head?