Using propane or butane as an inert gas for E-6 kit?

peter k. · Dec 29, 2021

Have used marbles up till now, but they can get troublesome, so have wondered how in the heck can you use a butane bottle with its short vertical feed cylinder to purge out the oxygen. You have to press it to release the gas, and there is quite a bit of pressure as it discharges.

For propane, understand and we do own a torch head and a propane bottle, and assume you turn it on low, ... of course unlit, .. but would love a better description on how to use it to seal a 3 bath E-6 kit. As in how to apply it to the bottle throat, at an angle or straight above it, without blowing the liquid out of the bottle? Also how do you know when you have used enough gas to force out the oxygen?
thanks p.

Sirius Glass · Dec 29, 2021

How about a tightly fitting top on a bladder bag? It is not explosive too.

Rick A · Dec 30, 2021

I've never used propane but I do keep a butane lighter recharge cartridge for that purpose. It doesn't require a large burst of gas to displace the O2 in your bottles as the gas is heavier than air and sinks to the surface of the chemicals and "insulates" the liquid from the air. Contrary to popular beliefs, it is not explosive.

Donald Qualls · Dec 30, 2021

I've used butane for blanketing gas for years. Never tried it with E-6, but it works fine for B&W chemicals like Dektol and D-23.

pentaxuser · Dec 30, 2021

Rick A said:
. It doesn't require a large burst of gas to displace the O2 in your bottles as the gas is heavier than air and sinks to the surface of the chemicals and "insulates" the liquid from the air.

OP the above sentence from Rick's post is the key. You are not required to fill the whole space with gas, merely enough to form an insulating blanket

pentaxuser

Donald Qualls · Dec 30, 2021

Rick A said:
It doesn't require a large burst of gas to displace the O2 in your bottles as the gas is heavier than air and sinks to the surface of the chemicals and "insulates" the liquid from the air.

Butane molecular weight: ~58, or roughly twice that of air, => density about twice that of air (density of gases is proportional to molecular weight at a given temperature and pressure). That's plenty of difference for the gas to stratify when allowed to rest a while.

Not to mention, the butane is stored in the refill can as liquid, and when the can is nozzle down, the valve will dispense liquid -- very VERY little of that is needed to evaporate into enough gas to fill the airspace at the top of a storage bottle.

And yes, it's flammable. Only explosive if mixed with air or oxygen at the proper ratio. Don't smoke in your darkroom (it's bad for you, your equipment, your chemicals, and your film, anyway). Don't use a candle as a safelight. If you shoot collodion, you already know this; ether is far more flammable than butane.

peter k. · Dec 30, 2021

Sirius Glass said:
How about a tightly fitting top on a bladder bag? It is not explosive too.

Nah thought about that before we tried the marbles years ago... understand they work good ect but looked into it, and decided not to.

Rick A said:
I've never used propane but I do keep a butane lighter recharge cartridge for that purpose.

OK, yes have one of these cylinders, to refill my gas soldering iron, but how do you use it? Tried it out on some dead first developer a couple of weeks ago, and had to press up on the cylinder with a needle nose plier and the pressure coming out of the can, blew some developer out of the bottle. Sigh ...

pentaxuser said:
You are not required to fill the whole space with gas, merely enough to form an insulating blanket

Ah because its heavier it will sit on the surface of the chems within the bottle and displace the oxygen. That makes it sound promising, but as from question above, how do you dispense it?

Donald Qualls · Dec 30, 2021

Mine came with several adapters to fit various refillable butane tools -- it turns out the one I installed to fill my torch lighter gives me enough grip to hold the can in hand and pull the nozzle with thumb and finger.

You do want to avoid holding too close to the liquid surface; when I've used this, it was mostly in a partly filled gallon pickle jar (mixed a 5 gallon Dektol in half the water, still had way too much stock solution -- but that Dektol stock has lasted fifteen years).

fgorga · Dec 30, 2021

Rick A said:
I've never used propane but I do keep a butane lighter recharge cartridge for that purpose. It doesn't require a large burst of gas to displace the O2 in your bottles as the gas is heavier than air and sinks to the surface of the chemicals and "insulates" the liquid from the air. Contrary to popular beliefs, it is not explosive.

The sentence that I have made bold in this reply is chemically nonsensical.

Yes, the butane is more dense than air and will tend to settle down through the air.

However, there will be significant mixing unless one takes extraordinary care. Then any movement (even careful, slow movement) of the bottle will cause some mixing of the layers.

Try layering a sugar solution under water (add food color to one of the solutions so you can easily see what happens) and watch what goes on. The principle is exactly the same for gasses.

Furthermore, this idea ignores diffusion. Over time the air and the butane will diffuse into one another and given enough time the gas above the solution will be of uniform concentration. The concentration of O2 in the resulting mixture will be necessarily lower than that of air, but there will certainly be oxygen in contact with the solution.

In order for blanketing to be truly effective one must use a volume of gas significantly larger than the headspace one is trying to fill.

Donald Qualls · Dec 30, 2021

fgorga said:
Over time the air and the butane will diffuse into one another and given enough time the gas above the solution will be of uniform concentration.

I guess the various places where heavier gas collects in a low place (like cold air in an ice cave -- a *very small* density differential -- carbon dioxide in a poorly ventilated mine, acetone vapor on a basement floor before it gets deep enough to touch the furnace pilot, etc.) have never read about diffusion.

Yes, you'll get a mixed layer at the interface, gradating from "pretty much pure air" to "pretty much pure butane" -- buy wholesale mixing will only take place if you move the bottle vigorously, and will undo itself to some extent.

Further, if you dispense from a refill can with the valve down, it's very difficult not to get enough liquid to push all the air out of the bottle. I used to be sure I waited long enough for the small pool of liquid butane to evaporate off the surface of the developer, mainly to be sure the bottle wouldn't pressurize and either blow the lid off or break the glass...

wiltw · Dec 30, 2021

You can use this product, a whole lot safer that using a combustible gas!
https://www.amazon.com/Private-Pres...ocphy=1013581&hvtargid=pla-352081173838&psc=1

"Replaces the air that seeps into an open bottle with a balanced mixture of carbon dioxide, nitrogen and argon to keep wine fresh"

Donald Qualls · Dec 30, 2021

wiltw said:
a whole lot safer that using a combustible gas!

And many times more expensive, too. Butane is a liquid in the can, that stuff can't be (not even at welding bottle pressures). I pay about 2/3 that for a can of butane that contains probably 20 times the mass of product.

And butane is really only hazardous if you smoke or have an open flame near where you use it. Lots of people (including me) carry some in a pocket, all day every day.

Sirius Glass · Dec 30, 2021

Really this makes life much easier:

www.StopLossBags.com

Donald Qualls · Dec 30, 2021

Those look more conveniently sized (for small batches) than wine bags, but I think I'll be very happy with the 5L wine bags I've purchased for my 5L EcoPro and Flexicolor replenishers...

Sirius Glass · Dec 30, 2021

Sirius Glass said:
Really this makes life much easier:

www.StopLossBags.com

Donald Qualls said:
Those look more conveniently sized (for small batches) than wine bags, but I think I'll be very happy with the 5L wine bags I've purchased for my 5L EcoPro and Flexicolor replenishers...

Not only am I really happy with them. I learned from them on Photrio. See if was more than worth the annual cost of joining!

gone · Dec 30, 2021

Donald Qualls said:
Lots of people (including me) carry some in a pocket, all day every day.

When I was welding many years ago, they started selling those Bic plastic disposable lighters. A lot of us put them in our shirt's top pocket w/ our cigarette pack, and a few of us made early exits from the living when the welder's sparks ignited the lighter, which is right where your heart is.

pentaxuser · Dec 30, 2021

So there you are OP It would appear that butane at worst will kill you and at best is unlikely to work. So as Clint would say: Are you feeling lucky, punk?

I have felt lucky in this matter for years but of course I have never faced Harry C with his .44 Magnum|

pentaxuser

Helge · Dec 30, 2021

I use a good, generous burst of butane in the developer bottle every time I use it.
There is an absolute minuscule chance of it igniting and causing any harm when the bottle is open.
Just take care of any sparks or open fire.
At worst, you’re just going to get a flame out of the bottle. But again, the chance of that happening is very, very low.
Once the bottle is closed tight, the chance of explosion is cosmic.
You’d have to cause a spark inside the bottle, and have enough oxygen present to ignite.

peter k. · Dec 30, 2021

Sirius Glass said:
Really this makes life much easier:

StopLossBags ...
Ohhhh yes, same concept of wine bags but much smaller and looking easier to use. Will investigate further into this item, thank you for the heads up.
Anyone else out there using these bags? Love to hear some more comments on them.

DREW WILEY · Dec 30, 2021

Wine making suppliers sell small oxygen displacement gas canisters (like wiltw linked); and large pressurized nitrogen and argon tanks can be easily obtained in most large cities. But there's nothing "inert" about propane or butane. I don't take anything for granted. Where I once worked was only a few blocks from a paint factory where they pumped out rail tank cars containing solvents like acetone and lacquer thinner. One day there was a deafening loud blast which shook our big commercial building way worse than any earthquake I have ever felt, and threw stuff off shelves all over the place. When I stepped outside there was huge gas cloud that almost looked like a nuke attack had transpired. When that cleared out, the entire specific steel rail tanker had been vaporized, and the worker pumping it out had forever entirely disappeared; but they did find his cigarette lighter laying there right beside the railroad track! Stupid is as stupid does.

That's an extreme example. But over the years, I've seen a number of industrial buildings burn down due to abuse of relatively small quantities of volatile solvents and flammable gases. It doesn't take much. There's a reason spark-resistant hammers and other shop tools exist, made of special alloys. But nobody pays much attention to the risk, and OSHA inspectors are about as common as Ivory Billed Woodpeckers in some areas. And heck, if a hundred other people feel safe crossing the Atlantic in the Hindenburg, why not you too?

peter k. · Dec 31, 2021

Volatile solvents... very good point and did not like the thought and the use during the first effort of trying the butane, but the marbles with E-6 chemistry doesn't work as well for me as it does with B&W so we wanted to investigated some more and see if somehow we could make it work.

StopLossBags seems for me to be the answer, and really like what they have put together. Years ago when we checked out wine bags, they where way to large a capacity for what we wanted, and cumbersome to fill ect, but StopLossBags has put together a good system to use with their quart pouches, filler tube, funnel ect, so we ordered four pouches last night, with the rest of the gear and will give them a try.

Sirius Glass · Dec 31, 2021

I used marbles and discovered that after a while the bottles would get really heavy so I found out about StopLossBags on Photrio and have used them ever since. Now what do I do with the marbles. If I throw them out people will say that I lost my marbles.

Using propane or butane as an inert gas for E-6 kit?

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