Regenerating actovated carbon in the microwave

[Cory]

Has anyone tried this? I seen this article that suggests it makes it work again.

"The regeneration efficiency of activated carbons reaches 98 % even after 10 times of regeneration cycles."

Effect of microwave heating on the regeneration of modified activated carbons saturated with phenol - Applied Water Science

The purpose of this work was to investigate the effect of microwave irradiation on the regeneration of modified activated carbons (GAC/MW, GAC/Ni, and GAC/Cu). The untreated activated carbon (GAC pure) was used for blank experiment. Microwave heating was used for preparation and regeneration of...

link.springer.com

It might even be better if the goal is color removal since absorbed metals done get removed from microwave radiation but organics seem to burn off.

 

[SDK]

It looks like they are introducing controlled amounts of nitrogen gas during irradiation. Cool article but unless I am missing something, I’m not sure it would be practical for the home aquarist.

 

[Cory]

How about this one?

Microwave regeneration of activated carbon used for removal of solvents from vented air - PubMed

A microwave regeneration of activated carbon used to remove organic solvents from vented air has been investigated. Methyl ethyl ketone (MEK), acetone, and tetrachloroethylene (TCE) vapors were removed from vented air through adsorption onto granular activated carbon. The saturated carbon was...

www.ncbi.nlm.nih.gov

 

[Dan_P]

Has anyone tried this? I seen this article that suggests it makes it work again.

"The regeneration efficiency of activated carbons reaches 98 % even after 10 times of regeneration cycles."

Effect of microwave heating on the regeneration of modified activated carbons saturated with phenol - Applied Water Science

The purpose of this work was to investigate the effect of microwave irradiation on the regeneration of modified activated carbons (GAC/MW, GAC/Ni, and GAC/Cu). The untreated activated carbon (GAC pure) was used for blank experiment. Microwave heating was used for preparation and regeneration of...

link.springer.com

It might even be better if the goal is color removal since absorbed metals done get removed from microwave radiation but organics seem to burn off.

Yes, definitely interesting. Thanks for the links.

If GAC wasn’t so cheap, regeneration of GAC would be on my list of projects. I think the hobby issue with GAC is not knowing when it is used up or whether it is doing its job, though not much of an issue because we change more often than we need.

Keep the reading material coming. You never know when we are going to find a link to the next big idea.

 

[Randy Holmes-Farley]

The idea has been around a long time and folks report some regeneration, but it is not complete or able to be done many times.

 

[Cory]

I tried it. It makes a few sparks. I wonder what that is?

Fwiw i seen a diy where a guy drilled a 1/2" hole and fed a tube with nitrogen gas being fed into it. He had a beaker with the carbon and tube going in. Not sure how safe that would be because the radiation might escape. Interesting though. Imagine being able to buy one like this thats safe.

 

[Scrubber_steve]

I tried it. It makes a few sparks. I wonder what that is?

Would it be the adsorbed heavy metals?

 

[Cory]

Would it be the absorbed heavy metals?

Ive wondered the same. No idea though.

 

[Randy Holmes-Farley]

I tried it. It makes a few sparks. I wonder what that is?

Fwiw i seen a diy where a guy drilled a 1/2" hole and fed a tube with nitrogen gas being fed into it. He had a beaker with the carbon and tube going in. Not sure how safe that would be because the radiation might escape. Interesting though. Imagine being able to buy one like this thats safe.

It makes no sense to me to try to drive out O2 in a home microwave oven, which presumably is what the N2 accomplishes.

 

[Randy Holmes-Farley]

Has anyone tried this? I seen this article that suggests it makes it work again.

"The regeneration efficiency of activated carbons reaches 98 % even after 10 times of regeneration cycles."

Effect of microwave heating on the regeneration of modified activated carbons saturated with phenol - Applied Water Science

The purpose of this work was to investigate the effect of microwave irradiation on the regeneration of modified activated carbons (GAC/MW, GAC/Ni, and GAC/Cu). The untreated activated carbon (GAC pure) was used for blank experiment. Microwave heating was used for preparation and regeneration of...

link.springer.com

It might even be better if the goal is color removal since absorbed metals done get removed from microwave radiation but organics seem to burn off.

just looked at the link. I would not extrapolate a trial using organics that can readily vaporize to say one can remove organics that bind from seawater that mostly will not readily vaporize.

 

[Randy Holmes-Farley]

Would it be the adsorbed heavy metals?

Don’t think they do anything different than other ions like sodium or chloride as they are not metallic.

 

[Cory]

It makes no sense to me to try to drive out O2 in a home microwave oven, which presumably is what the N2 accomplishes.

I thought nitrogen was large and that it helped create a bigger pore size?

 

[X-37B]

Not sure why you would even try but to each his own. I dig the small amount of carbon I use into my garden and call it a day lol.

 

[Cory]

Not sure why you would even try but to each his own. I dig the small amount of carbon I use into my garden and call it a day lol.

For me its availability issues. Rox .8 is costly in canada and i use a lot of it. Plus id rather spend 5$ a year regenerating it if possible than 500$ buying new carbon.

 

[X-37B]

For me its availability issues. Rox .8 is costly in canada and i use a lot of it. Plus id rather spend 5$ a year regenerating it if possible than 500$ buying new carbon.

Got it. My usage is only 4 tablespoons a month on my 120 so not an issue for me.

 

[Randy Holmes-Farley]

I thought nitrogen was large and that it helped create a bigger pore size?

No. N2 is very small and Air is more than 70% nitrogen already. I suspect in this case it is intended to sweep away the phenol as it vaporizes and reduced oxygen will keep the GAC from getting oxidized/burning and prevents the phenol from being oxidized to less easily removed compounds.

 

[Scrubber_steve]

Don’t think they do anything different than other ions like sodium or chloride as they are not metallic.

I don't understand Randy? Are you saying heavy metals are not metallic ?

 

[Randy Holmes-Farley]

I don't understand Randy? Are you saying heavy metals are not metallic ?

Correct. No heavy metals (or any metals) in reef tank water are metallic. metallic would be a chunk of, say, iron metal where most of the iron is Fe(0). Ions of iron, such as ferrous Fe++ and ferric Fe+++ are not considered metallic and do not behave in a way that chunks of metal do.

Chunks of metal in a microwave spark due to electric discharges at surfaces. Separate ions can’t do that. This article briefly describes it:

We asked a physicist: Why can’t we put metal in the microwave?

At a young age, we learned the golden rule of America’s favorite convenience appliance: never put metal in the microwave. But why? What would happen? Will it really burn the whole house down like Mom says?

www.google.com

 

[Scrubber_steve]

Correct. No heavy metals (or any metals) in reef tank water are metallic. metallic would be a chunk of, say, iron metal where most of the iron is Fe(0). Ions of iron, such as ferrous Fe++ and ferric Fe+++ are not considered metallic and do not behave in a way that chunks of metal do.

Chunks of metal in a microwave spark due to electric discharges at surfaces. Separate ions can’t do that. This article briefly describes it:

We asked a physicist: Why can’t we put metal in the microwave?

At a young age, we learned the golden rule of America’s favorite convenience appliance: never put metal in the microwave. But why? What would happen? Will it really burn the whole house down like Mom says?

www.google.com

Thanks, very informative.

 

[Cory]

Maybe the carbon has bits of metal in it? It makes like a popping electrical.