NaOH and Ferric Clorhidre

[patroclus]

Hello,
I would like to know where would I have to trough away NaOH (developer) and Ferric Clorhidre when I have to. Any idea?

 

[mramos1]

I do not understand the question?

 

[patroclus]

I know these products are toxic and should not be thrown away at any place (for example, WC). I'm asking how to get rid of them when you have to trow them away

 

[chemelec]

I Mainly just Neutralize the Ferric Chloride with Sodium Hydroxide, than dispose of it in my yard, watered down well with a garden hose.
BUT Make Sure You NEUTRALIZE IT to a PH 7

Once neutralized, its not really corrosive and not really very harmful.
I have even dumped it in my Vegitable garden.
A little copper and Iron won't hurt.

Sodium Hydroxide is basically "Draino", drain cleaner and can be safely flushed down your sink. It Won't hurt the Pipes.

 

[hyedenny]

Dumping your waste etchant in your backyard is really stupid, not to mention illegal. Copper compounds (cupric AND cuprous) are VERY toxic to the environment, at levels as low as 1uG/l. Youre probably dumping over 5,000,000 times that concentration (Do the math!). I realize that copper is an essential mineral (2mg/day US RDA), but dumping it in your vegetable garden is foolish, even though it IS just you and your family and neighbors eating and drinking it. Copper compounds are used in VERY low concentrations as effective pesticides and fungicides.

If you MUST dump it illegally, it should first be treated with soda ash (or other soluble carbonate) to precipitate out insoluble copper carbonate. Otherwise, it should be disposed of (for free) at a suitable hazardous waste disposal site.... And thats just the copper part ot the story.

You can also add your waste NaOH to the etchant; it will react with the hydrochloric acid in your waste etchant and at least partially neutralize either one to water and NaCl - table salt.

Shame on you for bragging about polluting. Your name "chem-elec" implies at least an interest (if not knowledge) in chemistry and electronics. From this and other posts - Im not impressed.

 

[Oznog]

Shame on you for bragging about polluting. Your name "chem-elec" implies at least an interest (if not knowledge) in chemistry and electronics. From this and other posts - Im not impressed.

You missed his other error. He recommended NaOH to neutralize it. NaOH is an extremely strong base. It will create a lot of heat if mixed with acid! This is potentially dangerous.

It is also possible to add too much and create a dangerously caustic solution.

And NaOH is far more dangerous to skin and eyes than the original ferric chloride solution. If you were uninformed enough to try to wash the powdered solid version off your skin instead of brushing it off you could get a chemical burn.

Actually Red Devil Lye is pure NaOH (lye). Draino liquid is usually NaOH but Draino powder is NaOH and aluminum powder and some other stuff. It's designed to make a violent reaction when wet.

Baking soda is far more recommended for neutralizing acids. I don't think there's a lot of reports of chemical burns from baking soda.

 

[patroclus]

I got confused as the 3 answers where completely contradictory!
So, I should neutralize ferric clorhidre with baking soda powder?
And NAOH can be safely be flushed down then sink?

 

[chemelec]

Yes I am well aware of What Draino is. Typically it is sodium hydroxide mixed with Pieces of Aluminum to create that violent action.
I don't use draino, but a pure sodium hydroxide.

I also don't just throw the sodium hydroxide crystals into the ferric chloride, I use a reasonably deluted solution of the sodium hydroxide.

patroclus, Yes, Sodium hydroxide is safe to pour down the drain.

Adding sodium hydroxide to Ferric Chloride Does not give a violent reaction. And if you read what I said, I said to only neutralize it to a PH = 7. I Never Said to make it Extremely Alkaline or in any way alkaline!

Considering the soil here is typically between 1% to 5% arsenic Whats a little copper. This town is built on an old gold Mine trailings site.
Lots of Cyanide Also.

Yes I do agree with adding the soda ash first and I do.
Just forgot to mention it.

 

[patroclus]

NaOH has to be reused everytime you develop a PCB or can be stored for some times??

If I got it, when I need to replace ferric clorhidre solution, first I put baking soda in it (how much?), then some NaOH diluted in water (how much?, apox), and then I can throw it away?

I will try to look for some safe place to deposit it, but meanwhile...

 

[hyedenny]

LOL!!!

Symptoms of Copper Poisoning:

Nausea

Muscle aches

Jaundice

Fever

Spewing ridiculous "facts"

Not knowing when to shut up


If your soil has 5% arsenic, THAT EXPLAINS A LOT!!! You should open up your backyard as a commercial arsenic mine. Youre trying to tell us that your soil has up to 5 kilograms of arsenic for every 100 kilograms of soil?! I dont believe it.

The safe limit is UNDER 20ppm parts per million! (20mg/kg is 20ppm.) Most soils are under 4ppm, and the target for water is 4ppt (TRILLION!). Besides, we're not talking about "a little" copper. Youre dumping A LOT - every time you dump it! The 6 most harmful metals in soil are Arsenic, Cadmium, Copper, Lead, Iron, and Zinc. Now we know where its all coming from. Thanks.

 

[Oznog]

I, too, am amused by the claim that it's ok because his place is a toxic waste dump anyways. Also confused since he just recommend it to everyone without first inquiring as to whether they live on a toxic waste site too.

Actually ferric chloride IS used as a fertilizer. However the used solution in question of course has a considerable mass of copper in it, and it's also acidic. As far as I can tell the ferric chloride itself is not an acid, but this is ferric chloride mixed with a moderately strong hydrochloric acid to improve the etching capabilities.

 

[patroclus]

Well, I suppose it would be better to ask to local authorities where should I take these things out, excecially Ferric clorhidre. NaOH I suppose I can throw it away, as some people use this compound and don't take any extra caution (not having anything to do with PCB or electronics).
Is that better?

 

[mstechca]

What I do is a little different.

I use my etchant and developer to the fullest extent (to the point where they no longer work).

Once that is done, I pour the used solution down the sink diluted with a gigantic amount of water. At least 1 part solution to 100 parts of water! That way, the harm is minimal. It is minimal as it is, because the solution becomes more ineffective, the more it is used.

the "solution" I talk about in this case can be etchant or developer.

But pouring it in the backyard could stink it up quickly, if enough is poured! :shock:

 

[hyedenny]

Ferric Chloride is a "Lewis acid." That is, it dissociates in water solutions (hydrolyzes) to form an acid solution, in this case, of HCl. The HCl does not directly aid the dissolution of copper - ie, copper is not attacked by HCl.
I always enjoy your posts, Oznog; youre one of the few who knows what theyre talking about when replying! Im not an expert by any measure, but I know when to shut up and when to ask.

 

[hyedenny]

Mistakeca - How is what you do any different?? Youre still polluting. The end result is the same. Using the etchant to its "fullest extent" just makes it that much more hazardous to the water tables. As usual, youre blowing smoke out of your acid.

 

[mramos1]

hyedenny: You go man... hehehehe

Amazing what I store in plastic bottle can be that bad for the environment. I have an old LARGE bottle in the garage, odd I never thought about what I would do with it when it stops working (probably because I do a couple 1x1 and 2x2 boards, 1-2 times a year). It keeps working, just takes longer to work over time.

Having a well we drink from and 3 young sons. Glad to read this post.

 

[George L.]

Ok...after doing some internet research and reading the thread this is what I understand...

Ferric Chloride should not be dumped into the enviroment no matter how dilute!

This is what should be done: Mix the used Ferric Chlorde with baking soda until it has a pH of 7, then let the copper settle on the bottom, it is safe to dump the liquid, but the sluge must be taken to a waste center.

Is this right?

Also, someone farmiliar with chemistry, can you tell me how many grams of Baking Soda are needed to make the solution a ph of 7 (does it depend on the brand/how much it was used up)

thanks,

George L.

 

[hyedenny]

It is safER, but not safe. Even if you manage to do a perfect titration, or neutralization, there will still be a high (read: unsafe) level of dissolved copper in the solution. It is much simpler to let the solution evaporate and take the powder to a waste site, or just take the whole kit-and-kaboodle to the waste collection site (or Chemelec's backyard). Luckily, there is one 10 minutes from here, and they dont charge any fees. The reason they dont charge fees is to encourage people NOT TO POLLUTE!

Adding baking powder to your waste etchant will take a while because you have to keep waiting for the foaming (CO2) to subside. The amount of baking powder to use depends on the concentration of your etchant and how much of it you have. Just add it until there is no more foaming and no more precipitate. Soda ash (washing soda) would be faster. Then you have to collect the precipitate - now you have to deal with the filtrate, AND the precipitate.

Another (more fun) way to get rid of most the copper is to RECLAIM it, by electroplating.... But thats another forum posting!

 

[chemelec]

If your soil has 5% arsenic, THAT EXPLAINS A LOT!!! You should open up your backyard as a commercial arsenic mine. Youre trying to tell us that your soil has up to 5 kilograms of arsenic for every 100 kilograms of soil?! I dont believe it.

Well back in the Gold Rush days, 1890's and early 1900's there were NO Polution Standards.

Yes it is That High. In some of the Tailing areas, Even Higher.
In Somewhat Recent times, they have covered them over with dirt and maneur, Just so they could make some plants grow, helping avoid it being blown all over the place by the wind.
Unfortunately there is no Great Demand for Arsenic and It is Quite Abundant all over the world.

This is an OLD Gold Mining town and most of the Pollution is courtesy of the "US Prospectors" coming here to get rich. The Ore was processed, Concentrating the Arsenic Content and the waste material were dumped where ever they wanted to.

Sodium Cyanide was also used in the Refining process and the empty cyanide drums were mostly just thrown anywhere. A lot of them were used for Septic systems. Guess where the Cyanide is Now?

All the gold from here was shipped by train, directly to the US.

By the time Pollution laws came into effect, Too Late. Those mining companies were no longer in a financial position to clean up much of anything.

Were talking about Millions, possibly trillions of Tons of contaminated soil.

As to POLUTION, I'm Quite sure you have Many Mining towns in the US that are Just as Polluted.
And Speaking of Pollution and the USA, When are you going to Clean up your Hydrocarbons going into the air and Distroying the Ozone Layer? Talk about a Major Problem!

And as to My Etching, I doubt I use more than 1 Liter of FeCL in a year. Mostly I use my Reverse Electro-etch Process as I show on my website.

 

[hyedenny]

Whats your point? That its OK to poison your family and neighbors because you willingly own/rent a house on top of a known toxic waste dump?? That the US (maybe even GW Bush himself) is responsible for your mistakes??

If you want to talk about the THEORY, not fact, Im prepared to debate you about the ozone layer/global warming scare. The US has WAY stricter emissions laws than does Canada. The only reason we might have more pollutants in the air is because we have more people, more industry and transboundary air flow.

Besides, goofball, HYDROCARBONS dont destroy ozone, they lead to its formation. Its Carbon Dioxide that is mainly to blame for any ozone depletion. So, if you'll do us all a favor and not exhale.....