Elementary, the reaction seems very tame, as described below (somewhat). As for piping HI (g) into a reaction, you’re on your own there. I have had two nasty incidents with suckback lately (including digging the remnants of a once nice thermometer out of a ceiling. Those mercury spill cleanup kits are pretty useless for acoustic tiles). Until I can cure my carelessness, I will be extra cautious. I am also looking for the no phosphorous route of HI reduction. Electro has been a bust for me, and more lab-oriented techniques are not possible quite yet. If I could get quantities of redP, I wouldn’t care so much about the HI. It does seem that HI (g) was spontaneously coming off of the small sample test of turpentine/iodine, indicated by the pinking of the pH paper in the neck of the flask (above post).
Results of second experiment:
Into a 1000mL Erlenmeyer flask were placed 300mL turpentine with 300mL distilled water. It was stirred vigorously with magnetic stirring for 5 minutes, and then poured into a separatory funnel. Upon sitting for 15 minutes, the layers were distinct, with a slightly cloudy water layer (bottom layer). The water layer was discarded, and the turpentine layer washed 2X with 150mL distilled water.
The now “clean” turpentine was combined into a clean 1000mL Erlenmeyer flask with 100mL distilled water, placed on magnetic stirring, and solid iodine added by the following schedule.
0 minutes 2.0g
12 minutes 3.0g
30 minutes 3.5g
40 minutes 5.1g
66 minutes 4.9g
For a total of 18.5g I2. Iodine was added without any planned timing, just when it felt right.
Results of each addition were very similar; the solution turned a dark brownish color, nearly black at times. No gas formation, no pressure increase, and no temperature increase. Slight fog condensing on walls of flask above the mixture, tested acidic to pH paper. At 80 minutes, the solution was removed from stirring and poured into a separatory funnel. Layering was much quicker than with unwashed turpentine (previous post), and very distinct. Lower water layer was a clear orangish-brown. Upper turpentine layer remained dark brown to black, even upon standing for one hour. Both solutions will be allowed to stand overnight in the dark and then inspected further. The pH of the water layer was 0-1, indicating a strong acidity of some sort.
To the separated turpentine layer was added 50 mL water, it was swirled, and then tested for pH. Strong acidity was again indicated, leading one to believe that either HI is trapped in the turpentine layer (likely), or that more halogenated terpene was continuing to condense and release HI into the water layer (also distinctly possible, according to the patent text).
It seems as if the earlier suggestions of using no water in the reaction and directing the formed HI (g) into a receiving vessel containing distilled water may be a better route. It seems as if the iodine would react quicker, also. However, I defend my original choice of using water in the experiment as a way to contain formed HI (g). After all, even failures provide valuable data. I prefer to start simply, and then gradually move to the goal.
My next route will be to bite the bullet and distill the acidic water layer, shooting for the azeotrope of HI (aq); then the turpentine layer, bubbling the vapors into a massed quantity of distilled H20. I found reference to turpentine boiling at 158 C, but do expect some trash to follow the HI since turpentine is a broad mixture of compounds. Simple distillation may work (30 degrees difference in bp), and will be attempted for the sake of simplicity. If that fails to produce a clean enough product, follow-up by fractional distillation will be performed. Copious temperature/volume data will be collected.
-->Since no apparent heat is released, I would expect that larger scale additions of solid iodine into washed turpentine would be relatively safe. If distillation works out, I will also be trying the tincture addition to turpentine for the solid iodine challenged in the audience.
All in all, I am still pleased with the results. I would definitely recommend to anyone else experimenting with this process to wash the turpentine first. Whatever trash was coming out in the water wash of the pre-reaction turpentine could easily carry over into the distillate.
More experimental results will be posted. Again, please provide feedback if even remotely relevant.
"Wyatt, I am rolling."