Tren Recrystal - Brown color in MeOH??

[sumatai]

Converting some expired (but sealed and refrigerated) pellets (5 carts).

I'm no stranger to the method so user error isn't a factor. Here is what's happening that's out of the ordinary:

- Deep brown/amber color on full pellet breakdown in MeOH
- extreme difficulty in early filtration steps (coffee, not syringe)
- very poor crystal yield (~20%) along with a milky white solution following distilled H2O titration
- more filtration problems trying to filter/wash crystal yield

All liquid amounts and measurements were appropriate. No heat source was used in the process, and the product was air tight until the experiment. Why the instant oxidation in MeOH (dark amber/brown liquid), why the EXTREMELY poor yield, why were the filters clogging so easily at every stage??

Attempting a 2nd conversion now with 3 more carts to see if it was an abboration, but already I'm seeing the same coloration before the pellets are even finished breaking down. The age of the pellets is the only variable, but everything I've seen on the topic says age isn't as big of a deal as exposure is.

Any ideas?

 

[Skye]

first off you are using the crystal fina method right? using methanol (CH3OH). the dark brown color is usually oxidized fina and recrystalizing it usually take care of that. and your using enough of everything?


try giving a detailed discription of everything you have done step by step.

 

[sumatai]

first off you are using the crystal fina method right? using methanol (CH3OH). the dark brown color is usually oxidized fina and recrystalizing it usually take care of that. and your using enough of everything?


try giving a detailed discription of everything you have done step by step.

1st attempt, tried 5 carts, dissolved pellets in Methanol (300ml) for 12 hours, nothing was done to accelerate the process. Breakdown was complete and binders seemed to separate well. Filtering was very difficult at every stage (compared to syno/prop filtering). Resulting liquid was a dark brown with white sediment.

Titrated approximately 900ml distilled H2O over a 3-4 hour time period. Precipitate was evident after the first 100ml or so. Soon after the resulting solution was an opaque milky white. The usual, but crystalization/clumping was not observed. Odd, sticky brownish yellow gummy material formed on the surface (appx. 2ml).

Solution was allowed to sit overnight. Upon filtering a yield of 2.5 grams (out of a potential 10g) was weighed out. Again, the filtering was VERY difficult. Crystal appearance was also a definite yellow compared to the typical off-white to whitish/yellow usually seen.

A 2nd attempt with 3 carts, repeating the process with adjusted amounts saw a more normal result, final yield has not been measured yet, but looks better than the first, proportionally.

 

[Skye]

1st attempt, tried 5 carts, dissolved pellets in Methanol (300ml) for 12 hours, nothing was done to accelerate the process. Breakdown was complete and binders seemed to separate well. Filtering was very difficult at every stage (compared to syno/prop filtering). Resulting liquid was a dark brown with white sediment.

Titrated approximately 900ml distilled H2O over a 3-4 hour time period. Precipitate was evident after the first 100ml or so. Soon after the resulting solution was an opaque milky white. The usual, but crystalization/clumping was not observed. Odd, sticky brownish yellow gummy material formed on the surface (appx. 2ml).

Solution was allowed to sit overnight. Upon filtering a yield of 2.5 grams (out of a potential 10g) was weighed out. Again, the filtering was VERY difficult. Crystal appearance was also a definite yellow compared to the typical off-white to whitish/yellow usually seen.

A 2nd attempt with 3 carts, repeating the process with adjusted amounts saw a more normal result, final yield has not been measured yet, but looks better than the first, proportionally.

I am really not sure. the only thing I can think of is that the cellulose filler went throught the coffee filter and messed up your batch.

The other possiblity is that you had some bad methanol, rather one bottle that had water in it. so some of the cellulose was in soluion as well.