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  1. #1
    argentic's Avatar
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    Glycol, TEA and Glycerine

    Quote Originally Posted by gainer
    Safer glycols
    I found an auto supply store that had the safe propylene glycol antifreeze. It worked as well as the ethylene. Another benign solvent that works is glycerol (glycerine at the drug store), but it is very viscous, even more so than HC110 syrup.
    Hi PAt,

    could you elaborate a bit more on glycerol (glycerine)? This is a ready available substance here in Europe, and AFAIK it's the least toxic of the glycol / TEA family. If it practically works as a non-active developer solvent, it would be an ideal candidate for a very environmentally friendly Phenidon - Vit C developer.

    Gilbert
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    Cours photo en Auvergne

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    Quote Originally Posted by argentic
    Hi PAt,

    could you elaborate a bit more on glycerol (glycerine)? This is a ready available substance here in Europe, and AFAIK it's the least toxic of the glycol / TEA family. If it practically works as a non-active developer solvent, it would be an ideal candidate for a very environmentally friendly Phenidon - Vit C developer.

    Gilbert
    I tested several developers in propylene glycol, dipropylene glycol and glycerine. The characteristics of the developers were affected very little, if any, by the solution.

    However, glycerine is very viscous and I found this to be something of an inconvenience in use as it made precise measuring more complicated than with the two glycols.

    Sandy

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    Quote Originally Posted by argentic
    Hi PAt,

    could you elaborate a bit more on glycerol (glycerine)? This is a ready available substance here in Europe, and AFAIK it's the least toxic of the glycol / TEA family. If it practically works as a non-active developer solvent, it would be an ideal candidate for a very environmentally friendly Phenidon - Vit C developer.

    Gilbert
    Gilbert, Polyethylene Glycol (PEG) is a good choice for those looking for a low toxicity, environmentally friendly preservative and solvent. The viscosity of PEG is much lower than glycerine. In fact, the material properties of PEG closely resemble those of water.

    "Polyethylene glycol (PEG) is a water-soluble lubricant from petroleum and/or mineral sources. PEG may be used as a binding agent, coating agent, dispersing agent, flavoring adjuvant, and plasticizer. Supplement manufacturers use it as a processing aid in compression enabling the tablets to hold together better. It also protects nutrients in the tablet from air and humidity.

    PEG is approved for use under the 21 CFR 172.820, and 173.340. It can be added to carbonated beverages, citrus fruit, non-nutritive sweeteners, tablets, and vitamin or mineral preparations.

    Synonyms and Brand Names (selected): Carbowax, Lutrol, Alkapoly Peg-200, Jeffox, and Pluracol."


    http://www.wholefoods.com/healthinfo/peg.html
    Tom Hoskinson
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  4. #4
    gainer's Avatar
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    You could keep the glycerine warm. I do that with TEA in winter, as it freezes at about 70 F. I have what we call a brisker oven, used mainly for letting bread dough rise, that keeps a temperature around 100 F. I don't think glycerine is any less toxic than PEG, but it may have the advantage if you use USP glycerine in place of tech grade PEG. You can certainly try a small batch to see if the viscosity will be a problem for you. That would be the only reason for not using it.
    Gadget Gainer

  5. #5
    grommi's Avatar
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    Hi, I have to revive this old thread, each time I search for phenidone and diluting it I come across this thread.

    Just tried to diltue 1 gram phenidone in 20 ml glycerine = glycerol. The viscosity is not the major problem but it doesn't dilute completely. I heated it in a mantle bath of boiling water and it diluted after some minutes, but after cooling down to roomtemp some crystals again dropped out.

    Then I added another 20 ml glycerine, so 40 ml total, heated it again as described above, and that's a perfect dilution at roomtemp now. Without heating so strong it won't dilute. The melting point of phenidone is about 120 °C, so I guess it won't do any harm. I thought it might be of interest for others and I guess this "concentrate" will have a long shelf live.

    1 gram phenidone in 40 ml glycerine

    Reinhold

    PS: glycerine is quite untoxic, LD50 is 5 gram/kg, no hazardous goods classification in Germany, classified as "not dangerous for humans", used as additive in food. I got 200 ml for 2 Eur in a drugstore.
    Last edited by grommi; 11-15-2014 at 09:39 AM. Click to view previous post history.

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    Glycerol is very hygroscopic and therefore contains water. In fact anhydrous glycerol is actually a solid. In this respect it is a poor choice for making water free developers. The best choice is propylene glycol as it is also non-toxic and easier to handle. MEA, DEA, and TEA are all alkaline and should be avoided unless the alkalinity is desired.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

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    Thanks for the additional info, Gerald. Indeed the melting point of glycerine is 18 °C, but it can be bought 99.5 % pure. pH is reported to be 5 - 7, which may be good for stability of the phenidone even if some water should be present. Mine seems to be pretty pure regarding the high viscosity. I want to use it as a stock solution for making Instol/Mytol etc. because phenidone has a poor solubility in water. Propylenglycol is also hygroscopic but has a more conveniant melting point of -68 °C. Propylenglycol would be easier to handle but glycerine is easy to buy here in local drugstores and cheap.

  8. #8
    Mainecoonmaniac's Avatar
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    I don't know much, but HC-100 has glycerol, thick as syrup and an opened bottle lasts for years. On a pyrocat thread, one person, Terry Christiansen mixes it in glycerin and his developer lasts a while. I wonder how you dissolve chems in such a thick medium?
    "Photography, like surfing, is an infinite process, a constantly evolving exploration of life."
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    Quote Originally Posted by Mainecoonmaniac View Post
    I wonder how you dissolve chems in such a thick medium?
    You need to heat the glycerol, then 1 g phenidone in 40 ml is not a big deal. But I have no clue how HC-110 is made and what it contains.

  10. #10

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    Here the solubility of ascorbic acid in propylene glycol is quoted as 50g/L but in glycerol it is only 10g/L:
    http://en.wikipedia.org/wiki/Ascorbic_acid
    Can you dissolve enough ascorbic acid in glycerol to make a useful concentrate?

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