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swmcl
27-Apr-2014, 17:35
Hello again,

I am wanting to hear the thoughts of people who have tried to give a partially filled container a squirt of a gas to remove the oxygen. CO2 is cheap and available in small pressurised containers for the aquarium business (it is used to give some boost to the plant life in the aquarium). Nitrogen might be found somewhere too - I haven't tried yet. The noble gases are found in the wine preserving business where (of course) they make all sorts of claims about the efficacy of using a noble gas ...

If one is removing oxygen won't CO2 suffice ? Perhaps for only a few chemicals - a developer or a fixer but not both ?

Experiences ?

Mark Woods
27-Apr-2014, 17:57
I decant the developer and replenisher. Whichever one is being used I use nitrogen to evacuate the oxygen & quickly cap the bottle. I've been able to keep the chemicals remain good. I don't worry about the other chemicals. I use to lose the developer about 3/4 through the bottle.

swmcl
27-Apr-2014, 18:18
Mark,

Nitrogen might be a more difficult thing to obtain in small batches. Is there a reason you didn't use CO2 in particular ?

Cheers,

Ian Gordon Bilson
27-Apr-2014, 19:58
With CO2 you run the risk of acidifying your solutions. A better choice would be butane gas.

BetterSense
27-Apr-2014, 19:59
What about cans of "air" sold for cleaning electronics? I believe they contain some fluorocarbon.

Mark Woods
27-Apr-2014, 22:38
I use the small tanks of nitrogen from a welding supply company. (I had to buy my first tank, then they give me another that is already filled.) The refills cost about $32 (tax including) for the small tank. It lasts about a year, or more. I use it when I load sheets of film & when I put negs into the enlarger. Sometimes I need to blow off the paper. I do very little retouching. I have the regulator set at 90 psi. It works great and is very inexpensive compared to the small cans of some non-disclosed type of gas.

I hope this helps. Oh, it's inert.

ArgentixCa
28-Apr-2014, 05:32
Just like that, adding glass marbles into the bottle will rise the level and leave the air out.
Unless there are some chemical properties that may damage the products, I never had any problem with the marbles.

Cheers!

Ken Lee
28-Apr-2014, 06:45
If you're operating a commercial lab, I can understand the need to keep a lot of chemicals around. If not, then there are plenty of formulas which can be prepared as concentrates and diluted before use (like Rodinal, HC-110, Pyrocat HD) and other formulas that can be mixed in small quantities just prior to use. There's nothing quite as fresh (and worry-free) as... freshly mixed :)

ic-racer
28-Apr-2014, 09:40
Hello again,

I am wanting to hear the thoughts of people who have tried to give a partially filled container a squirt of a gas to remove the oxygen. CO2 is cheap and available in small pressurised containers for the aquarium business (it is used to give some boost to the plant life in the aquarium). Nitrogen might be found somewhere too - I haven't tried yet. The noble gases are found in the wine preserving business where (of course) they make all sorts of claims about the efficacy of using a noble gas ...

If one is removing oxygen won't CO2 suffice ? Perhaps for only a few chemicals - a developer or a fixer but not both ?

Experiences ?

If the liquid was exposed to and equilibrated to the 21% oxygen in the atmosphere, most of the oxygen in the bottle is going to be dissolved in the liquid part. How are you going to deal with that? One way would be to put like a few 100 ml of you solution at time in a 20 liter tank and remove the O2 from the tank. Keep doing that until your dissolved o2 in the liquid is lowered to your liking.

Bruce Watson
28-Apr-2014, 18:31
IMHO, you are trying way too hard. This isn't at all a difficult problem.

The answer is already being used in the wine industry. Big thick glass bottles that are effectively impermeable for centuries. Then, pull a vacuum over whatever liquid is in the bottle, with a Vacu Vin Wine Saver (http://www.vacuvin.com/270/Wine_Saver.html). Problem solved.

I've had XTOL stock last 12 months (IIRC, Kodak advised 6 months max) in a wine bottle with a Vacu Vin stopper. Still had plenty of vacuum, developer was as effective as the day I mixed it (in steam distilled water of course ;-).

Jim C.
29-Apr-2014, 06:00
There is product called Bloxygen, it's sold direct and in woodworking supply stores, I use to pad out moisture
sensitive plastics that I use, it's basically a can of argon gas. It's kind of expensive, and I haven't yet tried
with dark room chems, but it may be economical enough to protect developer concentrates.

ROL
29-Apr-2014, 08:44
...I never had any problem with the marbles.

Frankly, it's never been much of a problem for me as I've always been told much of the oxygen is missing from any room I enter anyhow. Clearly, I've lost all my marbles, but I don't see why the OP can't just decant into a floating lid type container, where oxygen exposure will be minimal.

swmcl
30-Apr-2014, 00:58
I thank you all for your replies. As luck would have it, I had already ordered 4 cans of CO2 ... Anyone want 4 cans of CO2?

Ken, I do use Pyrocat-HD and I do use it mixed 15 secs prior to use. But !

I want to try some other things and they aren't the same. They have a fairly limited shelf life on the stock solution. Bruce, I want to try the Eco XTOL stuff and I need to do what you do. I'm also thinking of the paper chemicals down the track.

A little puff of N2 might be the go.

Cheers,

rwhb1
1-May-2014, 12:27
I did ask a while ago if a vacuum was effective. I have been using those vacuum pumps and stoppers for wine bottles, but have no idea what vacuum is achieved or the reduction of oxygen.

http://www.amazon.com/Vacu-Vin-0981450-Vacuum-Stoppers/dp/B000GA3KCE/ref=sr_1_1?ie=UTF8&qid=1398972429&sr=8-1&keywords=wine+vacuum

Russ