Chemical storage and Propane?

[BobF]

I have used all sorts of chem storage strategies and an absolutely full glass container seems to be foolproof for stock D-76. But of course I don't always have a full container and enough marbles to take up the slack just doesn't interest me. (what do you do with all those contaminated marbles when not using them?).

So when someone on that other forum mentioned using Propane to displace the air in a part filled container it got me interested, but.... Is it a good idea? Propane will displace the oxygen but will it contaminate the developer, fix, toner etc. Supposedly this is a poor mans copy of a product sold for this purpose by tetanol (sp?).

Is this more internet folklore or an actual good working solution? No pun intended.

 

[Donald Miller]

Since oxidation is the primary concern in storage of photochemicals anything used to displace air (oxygen) would seem to be beneficial. The chemical makeup of propane is C3H8 and does not contain any oxygen in and of itself.

However, in this instance there are factors which must be weighed. Among those is safety. Propane is a flammable substance. Any usage of propane should be prudent and within the parameters for which it is intended.

There are other gases which are capable of displacing oxygen and possessing of a far greater degree of safety. Among those would be nitrogen and argon.

 

[BobF]

There are other gases which are capable of displacing oxygen and possessing of a far greater degree of safety. Among those would be nitrogen and argon.[/quote]

Very true but the main attraction of propane is that it is cheap and easy to get. I have also heard that nitrogen (don't know about argon) is not good as it is lighter than air and therefore doesn't stay in the container.

 

[Donald Miller]

Another gas which potentially could be used in lieu of Nitrogen and Argon and that would still be safer then propane would be R 134A refrigerant. I don't believe that it would be nearly as flammable and it does not contain any oxygen in and of itself. It is available at most auto parts stores, Walmart etc. However, I would not discharge it inside an inhabited space, nor for that matter would I discharge propane under those same conditions. When I weigh the value of my A** to a little wasted developer the "apples and oranges" comparison becomes very apparent. But, hey, it's your deal...your mileage may vary.

 

[Robert]

It seems that dust off is the poor mans tetanol. The simplest thing would be one shot developer made to working strength. Easy enough to do if you mix your own chemicals. I guess the next thing would be a series of smaller bottles.

Personally I have the same fears about propane. Worse isn't it heavier then air? I really don't want to worry about it leaking in the basement.

 

[BobF]

Hmm......valid concerns about propane. I guess I am a little sanguine about it as I have for years used a lot of it in plumbing and camping but would never use it on a boat because it is heavier than air. I'll have to give that side of the question a little more thought.

Robert, what is in dust off? I have thought of that also but it doesn't list any contents on my can of Enviro Duster. Haven't bought Dust Off for years so I don't know what it might list.

Yep, I could use another dev or a bunch of small containers, but I like D-76 and mix it in a gallon ahead of time. Decant to 1/2 gallons but that leaves a lot of oxygen in the jugs as it is used up.

I am trying to avoid decanting to a bunch of liter size plastic bottles. But I don't want to get blown up either :twisted:

 

[inthedark]

Bob,

I still say that collapsable bladders like those used for hiking/camping are the easiest and best solution. Many of my chemistry (I buy 5-15 gallons at a time) comes in these, which is where I got the idea. Also depending on your desires, those vacuum seal kitchen bags (used to be called seal-a-meals) work quite well. I never used mine at home so I hauled it to work and viola!, get use now. And as it gets used down you can just cut off the extra length and re-seal. Or throw away and start again. When they need darkness for storage, I simply put that bag/bladder in a black plastic overlay.

Jill

 

[Robert]

We actually can't get dust off locally. It looks like a locally made knockoff is the only thing available.


Dead Link Removed

See if that works. If I remember right when I check it out dust off is similar.

 

[Robert]

I wasn't suggesting switching developers but mixing your own d-76. While you aren't likely to save any money by mixing your own you never have to worry about old developer.

I use D-23 and mix up whatever wierd amount I need. No need to store it. If you aren't using it stock then it should be easier to get everything mixed into the solution.

 

[clogz]

Of course there's Protectan made by Tetenal. (No longer available in the US?) And...the old photographer's trick: a drop of ether.

Hans

 

[Loose Gravel]

Not only is propane combustable, but in the right mixtures, it is explosive. The other thing that was not mentioned is that propane has similar dissolving powers to gasoline or alcohol. Propane valves and flex lines are different than those used for water or air.

It's not that I think that putting propane in a jar is especially dangerous, it is just having propane around and available is dangerous.

Consider a one-shot developer.

 

[Donald Miller]

The latest "dust off" type product that I bought does not identify the ingredients other then to say that it contains no HFC or CFC (both are broad indentifiers of refrigerants) and thus claims no ozone depletion capabilities. Beyond that I don't know what the product may contain. If it were to contain oxygen in any of it's forms or formulations it would seem to have the capability of entering into an oxidation of the developer.

I have found that with Pyrocat HD or ABC pyro that the mixtures I make up can be of fairly small quantities (if I so desire). This is my answer to this whole dilemna. I gain better tonal gradation and accutance as a primary result and the cost is lower then buying premixed developers. Since either of these developers are two and three part, respectively, the life of the stock solutions is greatly extended as well.

 

[Tom Duffy]

Bob,
When you say "that other web site" I assume you mean photo.net? To give you a photonet type answer , if you search the APUG archives, there was a tread about Protectan. you might see if there's any additional info.
take care,
tom

 

[bmac]

<sarchasim> If you use propane for your chems, be sure to plug the top of the bottle with a stick of TNT </sarchasim>

 

[Ole]

Now, there's no reason to head for the bomb shelters because someone mentioned propane. In the right mixture it is explosive, but so is just about anything. It is, at least, far less corrosive than air!

Personally I would choose butane. Heavier, lower boiling point, somewhat less explosive, and easily available in the form of camper's gas, or single-use cigarette lighters. You can protect an unbelievable lot of chemicals with the gas from one single giveaway lighter, especially if you find a company with a huge stock of now-politically-incorrect advertising material

I smoke, so I always have one nearby

 

[brimc76]

Bob, when I used to use Kodalith A & B developers I used to put them into the plastic bags from the home brew wine kits. The kind you put into a box with a plastic spout on the end. The have a UV or light exposure coating on the plastic and you can get most of the air out of them when you fill them. Once in the box you just open the spout and pour out what ever you want as the outside air pressure collapses the bag. It worked pretty good and kept the developer fresher longer.

 

[Jorge Oliveira]

Ladies, gentlemen

If, for some reason you notice I'm not posting anymore, it's just because my bottle of paper developer has exploded (-:

I have some butane left fom a lighter refil, and have put some inside the bottle.
Let's wait and see how well it keeps (although I usually finish one liter in about two weeks - 4 darkroom sections)

Jorge O

 

[Jorge Oliveira]

About non-cfc sprays, etc

Over here (Brazil) these non-cfc things (to my nose, at least) have a faint butane smell...

 

[BobF]

Ole, you almost say you have been using butane, but not quite. If you have then what is your experience with it and do you smoke when you are opening a used container? I don't care what I use as long as it is available and doesn't cost $100.00 just for the tank to keep it in. So butane would be fine if it works. Or Dust off?

In searching for more info I found one person that stated that the tetanol protectan that everyone seems to have liked was actually propane and is still available outside the US...????

 

[clogz]

I recently bought some Tetenal Protectan (400ml can) and it contains propane/butane. It is readily available here in the Netherlands and also in Germany. Can be ordered at: www.fotoimpex.de

 

[Jorge Oliveira]

About Tetenal Protectan, from Jobo site:

" A fourth way to extend the life of the solution is to use a non-oxidizing gas to replace the air in the bottle. Tetenal manufactures an aerosol (no CFC's) gas which can be sprayed into the mouth of the bottle to displace the air. As with all aerosol type products, avoid sparks, flames or smoking while using the products, because virtually all aerosol propellants are flammable."

So, a gas lighter refill bottle (butane) is way cheaper...

Jorge O

 

[Donald Miller]

I recently bought some Tetenal Protectan (400ml can) and it contains propane/butane. It is readily available here in the Netherlands and also in Germany. Can be ordered at: www.fotoimpex.de

I would imagine that is precisely the reason that it is no longer available in the United States. We have not had "tort reform" to the extent that some idiot blowing up his childs bedroom will be kept from suing the manufacturer's A** off.

 

[BobF]

Jorge O and clogz, thanks a bunch for that info. It seems that a butane/propane lighter should be suitable as long as I don't have any lawyers or government agents in my darkroom. I have one of those long nose barbeque lighters around here somewhere. If I can remove the igniter it should turn out to be the perfect solution.

I am going to run a test with half filled containers against full containers with and without gas in the half filled. I'll report back in several months.

 

[Jorge Oliveira]

It's HIGHLY advisable to remove the ignitor...

LOL

Jorge O