Putting fresh fix/stop into a bottle that used to hold spend fix/stop

[BGriffin23]

For warming/cooling in a tub to reach 20°C and to avoid mixing too much fix at once I prefer to mix only 1L of fix/stop at a time. But once spent I want to store them in larger containers to avoid having a gagillion 1L bottles for the annual trip to the regional waste disposal collection site. I was wondering if it's OK to reuse the 1L bottles without washing them out first (to avoid dumping anything down the drain more than necessary) even though this will mean a residue of spent chemicals will contaminate the new. Is this an acceptable practice or should I just accept the need to collect a lot of 1L bottles of spent chemicals?

 

[Sirius Glass]

No, the bottles much be thoroughly cleaned. I rinse out each bottles several times.

 

[MattKing]

Drain the bottles as completely as is practical.
Then rinse them.
Used fixer is mostly pretty benign. It has some silver in it, and silver is a bactericide, but if quantities are that small the deleterious effect will be less than minimal - about the same as washing your film and paper.
Unless your quantities are large - such as from a commercial lab - you won't damage anything.
There are other, more exotic chemicals that sometimes require more efforts, but tiny quantities of used fixer added to your waste water don't. The other things you put into your waste water are of greater concern.

 

[Doremus Scudder]

An acid stop bath can be disposed of down the drain with no qualms. Just dilute it first and follow with water to purge the line and further dilute. It's not a hazardous material. Acetic acid is the same acid in vinegar and the component of many stop baths. Citric acid, the other most common stop-bath component is basically vitamin C.

Rinse your used fixer bottles after draining well and before filling with fresh fix. The tiny amount of dissolved silver that you'll put down the drain is inconsequential.

A better way of dealing with used fixer is to recover the dissolved silver. You can do this yourself, but I prefer to take my used fixer to a local photo processor (yes, there are still some around). They are more than happy to do this for me since they get the silver they recover and I'm happy because I'm not dumping used fix down the drain. If you have a traditional photo processing shop near you, you could inquire as to their willingness to help.

Alternately, many municipalities allow small amounts of fixer to be disposed of in the municipal sewer system. You could inquire about that too. Fixer silver disposed of this way quickly combines with sulfur compounds in the waste water to become inert silver sulfides/ates/etc.

FWIW, the hazmat disposal site in my area has no idea whatsoever about photochemicals (they treated used fixer like some kind of toxic waste...) or silver recovery. They hauled away five gallons of used fix to be incinerated. Not very environmentally sound afaic.

Best,

Doremus

 

[Doremus Scudder]

Correction to the above: Citric acid is not vitamin C (that's ascorbic acid). I don't know where my mind was; too much Christmas cheer maybe?? Anyway, sorry for any confusion.

At any rate, disposing of citric acid stops down the drain is harmless.

Doremus