Monday, February 20, 2017

Dry Column Vacuum Chromatography (DCVC) - The Movie!

I have on several occasions been asked to make a DCVC video tutorial and quite liked the idea of doing so. Thus, I have started my acting career as you can see in the video below. I think the video will be a useful guide for first time DCVCers. For more info you should consult this and this blog post on DCVC. Many thanks to the University of Copenhagen's Communication Department, in particular Jacob Lejbach Sørensen, for investing some time in making this possible. D!


6 comments:

mike krigg said...

Its great, gonna watch it soon (After I set up reactions :D )
Is there any chance you will post more again on your blog? Lot of interesting stuff here but it seems that it slowly died :(

Daniel Sejer said...

@Mike Krigg: I doubt that I will ever get back to posting on the level I used to. I simply have too many things to do these days. However, I have been considering if I should start sharing my groups research on the blog if nothing else. Let's see if I get inspired. I have on many occassions encouraged students to write blog posts but they aren't really interested. However, it is still a nice resource blog that get's many visits (around 150 hits/day) so I'll keep it up and running and will continue to answer peoples questions. D!

emunfred said...

In my previous job I used DCVC a lot. I had the glassblower modify some glass filter funnels to be taller. I used them in several diameters, up to about 10 cm, and separated up to about 50 grams of crude per run (as I recall). I also used the system with butanol-acetic acid-water to separate some very polar compounds.

Dennis Parker said...

Hello from Oregon USA, and thank you so much for taking the time to pass along this great video. It turns out that I had resorted to this idea on chance as I was purifying some plant extractions. I tried with my hobby grade chromatography tube to get seperation but needed a way to do this much more efficiently and scalable to my process with normally requires 28 grams or so at a time to be purified.

In Oregon it is perfectly legal to grow marijuanna and also to obtain the extractions of marijuanna done by supercritical fluid extraction. The problem I have as a medical user is that at best the dispensary grade extracts test at 70-80% THC nominal. This leaves significant contamination of the target medicine in he extract meant ultimately for inhalation via a vaporizing device. Respiratory irritation is a huge problem for most users needing relief of this medicine. I have learned to remove a good share of the irritants, mostly Volitile Organic Compounds (VOCs) which are known by users in Oregon as terpenes. This GREATLY enhances the potency and medical efficacy of the product. I noticed during chromatography runs in my standard chromatography tubes that there was significant material being held up on the alumina from the extract when isopropyl alcohol was used as the mobile phase.

So as a filter idea only I placed a few inches of alumina into my buchner funnel equipped with a fine frit. The process outshined ANY other filtration method for purifying that I had tried but moreover I saw the potential for seperation and not just filtration in the process. Then my internet search on the idea produced your excellent video! Nice!

I know in great detail the problems that processors have run into trying to produce a purified product here in Oregon. I can tell you without hesitation that the process you so thoroughly document will without question become the standard against which other pufification techniques are judged. In just minutes the filtration process using alumina and isoproply alcohol/water accomplished what can take many hours to do otherwise and does so MUCH better. I realize that my use of alumina deviates from your video but at the moment it works very well and is extremely inexpensive to,purchase from Amazon in an abrasive grade bulk container. The isopropyl alcohol is also inexpensive on Amazon and has a huge side benefit when combined wih water and used in purification but that topic is a different subject altogether.

Thank you so much for advancing the knowledge!

xmac1x said...

Great video and great to see you back Daniel. Your blog was great help to me during my PhD and I tried DCVC a number of times!

Daniel Sejer said...

There is an interesting discussion on DCVC going on at Reddit worth checking out: https://www.reddit.com/r/chemistry/comments/5v5qq1/dry_column_vacuum_chromatography/
D!