Phenidone in Glycol some problems

I was mixing some Gainer's formulas and with what remain of Glycol I tried to put in solution Phenidone.
I had 40 ml of Propylene Glycol heated at 60 C. (140 F) and I tried to dissolve 20 grams of Phenidone. While the PG was at the right temperature the Phenidone gone in solution....when it cooled a sort of white mud start to increase in the solution. It seemed that the Phenidone increase the volume and turn in a form of white mud. I added another 40 ml. of PG and stored everything in a brown glass bottle.
Do you think it will work? Have you noticed something similar?
In the developers I made this morning with Phenidone nothing happened, it got in solution easily at 55/60 C.
Daniele

I had a similar result when I tried to dissolve a rather large quantity of Phenidone in propylene glycol. The solution had a "curdled" appearance after it cooled to room temperature. "White clouds" is another descriptive term I have used. I resolved the problem by increasing the amount of propylene glycol until all of the Phenidone remained in solution at room temperature. The resulting stock concentrate works fine (it is about 6 months old now).

supersaterated solution

I have not tried to do this myself...phenidone/glycol. If one uses a warm solution and puts in as much as can be dissolved at an elevated tempertue then when the solution cools you will have a sludge or other situation that is caused by overloading the solution. This is called a "super-saterated" solution. I have no idea how much pheidone can be put into a given volume of glycol It does seem to me that this is what happened here. I would add enough glycol to arrive at a larger solution volume and I would expect that the problem will go away. It is, I believe, important that you know the solution volume percentage so that when you add solution to a developer you know how much is required to make an existing formula.

Claire Senft said:

...It is, I believe, important that you know the solution volume percentage so that when you add solution to a developer you know how much is required to make an existing formula.

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Yes indeed!

I had a similar problem making a phenidone stock solution in alcohol (food grade 95%). More phenidone would dissolve at even slightly elevated temperatures. On cooling, some would crystallize. Warming again would dissolve it. Even more inconvenient was the fact that my developer did not work at all well. I put it down to the alcohol having some water in it. Now, what am I going to do with the rest of the unused 95% spirit?

Now I have sourced some Dimezone-S which dissolves in aqueous developer fairly easily (at Pyrocat-HD concentrations). For me this obviates all problems with solvents, and it lasts better than phenidone (well that's what they say, anyway)

ongarine said:

I was mixing some Gainer's formulas and with what remain of Glycol I tried to put in solution Phenidone.
I had 40 ml of Propylene Glycol heated at 60 C. (140 F) and I tried to dissolve 20 grams of Phenidone. While the PG was at the right temperature the Phenidone gone in solution....when it cooled a sort of white mud start to increase in the solution. It seemed that the Phenidone increase the volume and turn in a form of white mud. I added another 40 ml. of PG and stored everything in a brown glass bottle.
Do you think it will work? Have you noticed something similar?
In the developers I made this morning with Phenidone nothing happened, it got in solution easily at 55/60 C.
Daniele

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20g of phenidone is a huge amount. You probably hit the solubility limit of phenidone in propylene glycol. Stick with more dilute solutions and you'll do fine.

In point of fact, I never recommended any stronger than 1% solution of phenidone in either alcohol or glycol. The major reason for such weak solution is that the very small amounts needed in working solutions are difficult to weigh even to within 10% accuracy. Even a liter of a PC-Glycol or PC-TEA concentrate only requires 2.5 grams, and 20 to 40 ml of that solution will make a liter of working solution. So you're talking about 0.05 to 0.1 grams of phenidone which in 1% solution is still only 5 to 10 ml / liter of working solution.

Many thanks for all the reply and suggestions
I was keep into the chemical syndrome.
I have two questions after that:
- Tom you done the same mistake and you also corrected it, how is the ratio between Phenidone and PG to have a completely dissolve agent?
- Do you think Phenidone will be still working?
I ask this because it seems that a hasty happened.
Next time I will follow more the indications Mr. Gainer...since my approach with chemical is very primitive.
Daniele

ongarine said:

Many thanks for all the reply and suggestions
I was keep into the chemical syndrome.
I have two questions after that:
- Tom you done the same mistake and you also corrected it, how is the ratio between Phenidone and PG to have a completely dissolve agent?
- Do you think Phenidone will be still working?
I ask this because it seems that a hasty happened.
Next time I will follow more the indications Mr. Gainer...since my approach with chemical is very primitive.
Daniele

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Hi Danielle,
To refresh my memory, I checked my lab notes and pulled out my bottle of Phenidone/Propylene Glycol Concentrate and took a look.

I mixed the concentrate on 4/30/04. I dissolved 7.5 grams of Phenidone in 100ml of Propylene Glycol at 150 degrees F. The resulting solution was clear - no sediment or cloudiness. The color of the solution was yellow with a slightly brown tinge. The solution was stored in a clean, new Nalgene bottle.

After the concentrate cooled, I noticed a white cloudy suspension in the liquid and a bit of sediment. The overall color of the solution remained yellow with a slightly brown tinge.

I heated the solution for about 40 seconds in a microwave oven. With a bit of stirring, everything went back into solution.

I knew I would need to add Propylene Glycol in order to keep the Phenidone in solution. For measuring convenience, I added sufficient Propylene Glycol to make a total volume of 250ml. At my lab ambient temperature (controlled to 70F - 71F) the Phenidone has remained in solution.

This morning, I performed a "quick and dirty" test of the concentrate's activity. I used a 1.5 cm piece of 35mm Kodak Tech Pan (exposed to room light). I dissolved a little sodium sulfite and sodium carbonate in 60 ml of water. Then I added 2 drops of the Phenidone concentrate and stirred the mixture. I dropped the piece of film into the mixture and agitated it. The film emulsion began turning gray in about 30 seconds. At the end of 3 minutes it was a dense black - QED.

What I have here is a highly concentrated stock solution (3% is a high concentration - in Phenidone terms). As such, it is difficult to measure - it requires a pipette or an eyedropper. I will probably dilute it more with Propylene Glycol.