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Chemical storage - why don't they......?

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Sim2

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Was having a random thought about storing chemicals and wondered why...?

Plastic seems to leach oxygen into the liquid, oxidising it;
Glass is the preferred option as this doesn't leach oxygen, though;
A partially filled glass bottle has oygen in contact with the fluid - oxidising it.

Why don't glass bottles come with a thin floating lid inside them to minimise the contact area with the oxygen in the part filled bottle?

Not sure how this would be done - but they do get ships inside bottles :whistling:

Then I got carried away with thoughts of bottles like bar optics; upside down on a rack with "twiddle" knobs to dispense at the base and floating lids!

Just a thought, but why not?

Sim2.
*dreaming*
 
If you were so inclined you could always draw a vacuum on the glass bottle then fill it with an inert gas after every use, or have it hooked to a lightly pressurized inert gas canister so you had a dispenser style system with inert gas as the propellant.
 
Or just fill the bottle with glass marbles until the fluid level reaches the top. I know, not brainstorming the OT but I have always tried to ascribe to any KISS method applicable, myself.
 
They did make metal containers with floating lids and bottom spigots at one time. I have 2 of the cans with no lids. I also have a heavy duty plastic container with floating lid and spigot. These were very handy, but have vanished as time went by.

PE
 
have it hooked to a lightly pressurized inert gas canister so you had a dispenser style system with inert gas as the propellant.


Ooooo, I like this one - just need to rig it up to a multi-outlet handheld dispenser like they use for soft drinks. Nothing can go wrong here!!!
 
I also have a heavy duty plastic container with floating lid and spigot. These were very handy, but have vanished as time went by.

PE


Now I remember that at one agency we had big plastic containers with floating lids to feed the E6 dip and dunk, also for the Mutigrade print processor - but I reckon the 2 litres or so of chemicals I use now would be like a small puddle in the base of these monsters :laugh:
 
Or just fill the bottle with glass marbles until the fluid level reaches the top. .

Yep, this is the sensible solution that I know I will end up with. As you say, KISS.

But oh, the dreams of automated pressurized non-oxidised chemicals on demand. :blink:
 
Or just fill the bottle with glass marbles until the fluid level reaches the top. I know, not brainstorming the OT but I have always tried to ascribe to any KISS method applicable, myself.

I did this with a gallon of paper developer. By the time I had used 3/4s of it, I could hardly life and accurately pour from the bottle. That was the last time I did that. I bought accordian bottles. :smile: Yes, sometimes they leak in air. :sad:

Steve
 
Where could you get small bottles of nitrogen?

Just use Nitrogen! Works perfectly with just about any container.

PE
I've seen canned argon as a wine preservative. Where can you get nitrogen? I've heard about some folks using "canned" air as a preservative. I don't know if it's inert nor the impac on the environment. I use a very old an of Beseler spray can of developer preservative. It's claimed to be heavier than air so it will sink to the bottom when sprayed into a bottle f developer. I'm now experimenting with those Mylar bladders used for those take away coffee boxes. The problem is that I can't find spigots did them.
 
Nitrogen is available at most shops for welding equipment.

I've posted the necessary equipment and rough costs in a similar thread this week.

PE
 
Some time ago I did a deep search on APUG on this matter and the solutions gathered are:

- Use dark beer bottles and fill them with marbles. The problem here is that if you do this with big flasks the marble will make them very heavy.

- Use vacuum device that wine-lovers use to extract air from half-bottles of wine. Don't breath too much during pumping...

- Somebody freezes the plastic containers. This can be handy but it is not the proper thing to do for better results. When I asked Marco Berti at Ornano about freezing he said not to do it in an emphatic way. Some people do it though, and in order to dissolve the crystals which are formed they warm up the solution and filter it (!). Instruction for my E6 chemistry tell to preserve above 12 °C.

- A variation of the freezer trick: Make the diluted solutions, pour them into small plastic bottles, freeze them, so that you unfreeze only the quantity you need. You would also need a freezer just for taking chemicals! Again, this is not recommended for best quality for what said above.

- Fill the bottles with inert gas, such as Nitrogen, Argon, or mix of propane - butane (lighters refill). Lighters refill is, well, inflammable so some caution is needed.
Nitrogen can be bought in cylinders. You have to make a little investment in the tools to use it, but then it will be very cheap. The problem with this method is that inert gas can be dangerous, if it leaks in your house you can make the "white death", just like with carbon monoxide. I would not adopt this solution unless I can store and use it in a safe way (store in a constantly "aired" room, use it outdoors).

I use Tetenal "protectan". Reasonably cheap, very convenient. Bleach and pre-bleach should not need it anyway, and also final rinse should not need it, so I suppose one can save protectan using it only on first developer, inversion, colour developer, fixing.

Fabrizio
 
Small one time use bottles. Mix a gallon of print developer and store in 8 oz glass bottles.

D76 goes into 4 oz bottles.

Specialty bottle Company, but there are others.
 
Any of the inert welding gases should work, right? Like an argon/co2 mix that one would have for a mig welder?

-Ed
 
That's what I like about being here - no matter how daft or frivolous a thought might be, there always seems to be a raft of suggestions on how to make it real!

Sim2.

*Sim2 and the argonauts*
 
- Use vacuum device that wine-lovers use to extract air from half-bottles of wine. Don't breath too much during pumping...

I have done this for coffee beans. The difficulty is that those things are designed to work with wine bottles, not any bottle opening, which is a pain with beans, though possibly less so with liquid chemistry. Just find some 1 liter bottles and you're all set. Or mix all your chemistry in 750 ml batches.
 
Heat the bottle the chemicals are going into and then insert a spigot into the mouth of the bottle, connect a hose to the spigot and the chemical you want in the bottle. Then cool the heated bottle the chem will be going into, as the bottle cools it will draw the chem into it, wall-a.
 
Why don't glass bottles come with a thin floating lid inside them to minimise the contact area with the oxygen in the part filled bottle?

I think you are asking the wrong question. A more interesting question is more along the lines of: "How can I best store my chems.?"

Best I've found, even better than a floating lid in a closed container, is the combination of glass and vacuum.

I store my chems in old wine bottles (bottles that are designed expressly to keep oxygen from getting to the contents), and use the VacuVin vacuum stopper system.

Works amazingly well. Stock XTOL from a half filled bottle, but under vacuum, was perfectly fine 12 months later. Hard to image doing any better than this.
 
The best way to insure the your chemicals remain fresh is to only mix what you will use in a reasonable time. If you are only an occassional user then stay away from the larger sizes. The unit price may look good until you have to discard spoiled developer.
 
I think there are devices available for wine lovers to fill the empty space above the vine in an opened bottle with nitrogen. I don't think they rely on injecting the N through the cork. This would be a lot simpler than cooking up a mix with welding gasses, etc. Someone suggested butane, propane should also work but either would present a possible fire hazard. Talk about a "dynamite picture...."
 
Not all plastics are bad for storing developer. Polyethylene terphthalate PET and polyvinyl chloride PVC are good choices. PET, SBI # 1 is almost as good as glass in not being permeable to oxygen. PVC, SBI #3 would be a second choice. The SBI number is the number in the triangle for recyclng purposes.

Remember this rule using the SBI numbers. 1 and 3 for developers and 2 and 4 for fixers and everything else.
 
Any of the inert welding gases should work, right? Like an argon/co2 mix that one would have for a mig welder?

-Ed

One caution about gas mixes that contain CO2: CO2 can shift the pH of at least some developers. For example, if the developer contains potassium or sodium hydroxide, the hydroxide can react with CO2 in the gas mix, converting the hydroxide to carbonate. Carbonate is a weaker base than hydroxide, so the pH of the solution will shift to lower pH, making the developer less active. The same thing will happen to some degree with developers containing buffers, though I don't know how serious this problem would be for those solutions.
 
Not all plastics are bad for storing developer. Polyethylene terphthalate PET and polyvinyl chloride PVC are good choices. PET, SBI # 1 is almost as good as glass in not being permeable to oxygen. PVC, SBI #3 would be a second choice. The SBI number is the number in the triangle for recyclng purposes.

Remember this rule using the SBI numbers. 1 and 3 for developers and 2 and 4 for fixers and everything else.

Ooo, I like this info. Up to now, plastic bottles seem to be regarded as the devils crucible for chemicals so thanks for the info esp the SBI numbers. Good call.

Sim2.
 
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