My friend informed me of some strange things that occured since the last post he wrote. So, he had the crystals drying in the containers from the freeze precipitaion, while at the same time drying the decanted naphtha in a evaporation dish. He left it for most of the day to dry (12 hours). When he came back, all the containers that had some crystals in the beggining, as well as the evaporation dish, had nothing but a yellow oily looking residue at the bottom.
He was very glad he kept everything in the container instead of filtering through coffee filters to say the least.
At this point, he is not too sure what to do. He thinks he remembers seeing a similar problem somewhere in the forum, so is going to research into it. He just wanted to keep everyone updated to his progress.
Edit: Since my friend lives in a really humid location, do you think this would have anything to do with seeing only a yellow oily residue?
He is going to recrystallize what he has, and see what happens.
Edit #2: Well, some research and trial later (about 2-3 hours), here is what happened. 25mL of Naphtha (VM&P) was heated in a water water bath until the naphtha was hot to the touch. This was then added to large a mason jar containing a noticable amount of the aforementioned "yellow oily residue". A rubber spatula was then used to agitate the residue into solution; however, most of the residue was insoluble in the naphtha and stayed at the bottom.
During this process, the naptha turned a bright yellow color. This was continued with all the containers with any noticle resiue.
Since this was a large volume of naphtha in total (about 100mL), this was evaporated with a fan. Within 5 minutes, it started turning the milky color described in other posts (as well as seen during the freeze precipitation earlier). Now, another freeze precipitation is being performed before an estimate of further cleanup is needed.
Edit #3: Well, after letting sit in the freezer for about 8 hours, the container was removed, decanted, and allowed to evaporate under fan an hour (still continuing). When the container was removed, my friend was quite surprised to see so much white stuff on the bottom; although it went immediately back to the yellow oily residue as soon as it warmed up to room temperature. My friend is almost baffled by all of this. For right now, the resiue is drying and will continue to dry for the next hour or so. He is not sure what is wrong. For the time being, he is going to hit the forum again and see if he can find something else while waiting for any changes.
The only thing he can think of is that he has a lot of impurities from having too much naphtha while extracting.
Well, actually, there is one more other thing. . . he thinks that living in a country that is really hot and really humid has something to do with it. The reason is this. Pulling out a really cold container in a hot/humid environment encourages thermophoretic deposition of the water onto his precipitate. In other words, the water condenses onto the surface of his precipitate from an extreme difference in temperature. As such, he is going to redissolve this again in a minimal amount of hot naphtha, then gently heat this in a water bath. Afterwhich he will evaporate all the solvent off. Sounds like the best way. . . .at least it worked last time.
Hopefully last edit: Well, the answer was found after reading through a good 340 posts of mainly repeated questions such as my friend's. He was correct that the humidity was the cause of all the troubles. He now knows to CAP THE CONTAINER AFTER YOU DECANT. From there, wait for the the wet crystals to approach room temperature. Then you can open the container to finish evaporating. He thinks doing this next time would make it easier and quicker. Lessons learned and lots of good stuff read. He says he will keep everyone updated with what happens.
Thanks for taking the time to read through his lab notes!!
ImPersonal Note:
First of all, you (guys/gals/non-gender specific entities) kick all sorts of good stuff. Even though it took a healthy amount of time, my friend was able to find invaluable information within your vault. My friend hopes that his experience is helpful to someone. . . . experience really is the best teacher.
My friend says it is so close he can almost taste it. This has been a LONG time in the maing (1-2 years), and he feels as ready as he possibly could be. Here's to hoping for a nice final stretch. . . . .
The above is nothing more than theoretical conjecture and in no way should be done by anyone