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  #1  
Old 1st July 2022, 06:57 PM
Nat Polton Nat Polton is offline
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Default Preserving Phenidone

Reading a post here, the shelf life of phenidone can be from a few months to tens of years.
One preservation solution is to dissolve it in polypropylene glycol.
This method also helps in measuring small amounts.
P.Glycol is not cheap so I thought about other cheaper ideas.

I don't know if this has been thought of before but I am thinking of placing the small jar of phenidone into a larger jar and leaving the lid off the phenidone.
Next fill the larger jar with gas lighter fuel or Tetenal Preservative spray.
This should fill the small jar with the gas without blowing the powder all over the place.
Eventually tightening the lid on the small jar.

I wondered if anyone has recommended or used this method before?

Any pitfalls would be most welcome.

Thanks in advance and
Cheers
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Old 1st July 2022, 08:49 PM
Michael Michael is offline
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Protectan into a bottle of concentrate is simple, as the gas covers the flat surface evenly. Your idea seems to me problematic, as the surface needing to be covered is complex in shape.
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Old 2nd July 2022, 10:33 AM
Nat Polton Nat Polton is offline
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Good Morning Michael.
I may not have been very clear.
My Phenidone is a powder.
If I give it a blast with butane or Tetenal Protectan, it would be like blowing into a tin of snuff, pretty messy.

So if I fill a larger jar with butane and lower the smaller opened jar of phenidone into it , hopefully the gas would flow into the smaller jar, and no mess.

Cheers.
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Old 2nd July 2022, 11:06 AM
Mike O'Pray Mike O'Pray is offline
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Nat, if you fill the big jar with enough butane and do not disturb it as you lower the phenidone jar into it and it is totally submerged in the butane then provided butane is not detrimental to powder phenidone my unscientific brain says it cannot see any reason why it won't work.

If it does then the only other issue is disturbing the butane and presumably needing to refill the jar each time you use the butane

Unless there is a good scientific reason why it won't work then you'll only know by trying it

However in John Finch's video on preserving phenidone I thought he mentioned glycol as being at a reasonable price

I vaguely recall he got it from Amazon. His video on Pictorial Planet may be worth a look

One of the big benefits from what he does by using glycol would seem to be that all doubts about its longevity are removed and using phenidone in liquid seems a very easy way to use it

Mike
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Old 2nd July 2022, 12:20 PM
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Reginald S Reginald S is offline
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I can't imaging covering and protecting powder which contains a lot of oxygene, too.

For my developers covering with cheep Propan/Butan gas works fine because there is less oxygene in the solutions and the protection from new oxygene is given by the gas cover.
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Old 2nd July 2022, 12:33 PM
Michael Michael is offline
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Quote:
Originally Posted by Nat Polton View Post
Good Morning Michael.
I may not have been very clear.
My Phenidone is a powder.
If I give it a blast with butane or Tetenal Protectan, it would be like blowing into a tin of snuff, pretty messy.

So if I fill a larger jar with butane and lower the smaller opened jar of phenidone into it , hopefully the gas would flow into the smaller jar, and no mess.

Cheers.
No, Nat, I understood you clearly. Lowering the smaller jar into the larger will cause unpredictable displacement of the inert gas, which may not end up where you want it.
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Old 2nd July 2022, 01:40 PM
Mike O'Pray Mike O'Pray is offline
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Nat, here's the video
https://www.youtube.com/watch?v=jWGhfr1qUv4

It was Amazon and he says he got a litre for about £6 so not a fortune. One of the comments says that more than 5 years was possible in that person's case

Mike
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Old 3rd July 2022, 12:01 PM
Terry S Terry S is offline
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Quote:
Originally Posted by Mike O'Pray View Post
Nat, here's the video
https://www.youtube.com/watch?v=jWGhfr1qUv4

It was Amazon and he says he got a litre for about £6 so not a fortune. One of the comments says that more than 5 years was possible in that person's case

Mike
It seems that the price has gone up since the mention of Amazon's price. Having just checked both Amazon and eBay, one should expect to pay upwards of £12 for a litre now.

Also, a lot of the listings sell a mix of propylene glycol with glycerine, which is used in e-cigarettes I believe. So is this mix what is required, or do we need to look for 100% propylene glycol, for which there are fewer listings?

Terry S
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Old 3rd July 2022, 02:19 PM
Mike O'Pray Mike O'Pray is offline
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My goodness! The video is dated 2021 and OK the glycol may have been a few years old by then but a doubling of price"

If things go on this way my income will end up being stretched to pay for food, council tax and heating only

Mike
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  #10  
Old 4th July 2022, 07:33 AM
Lostlabours Lostlabours is online now
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What are you preserving Phenidone from

My 1961 Ilford Pjenidone is as good as fresh Phenidone. In 46 years of using Phenidone I've never had any go off.

Ian
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