Somehow today I ended up on @Carmendrahl‘s old blog and found this post on Kugelrohr distillations (“The tastiest distillation there is”). I have spent the last year doing regular distillations and kugelrohr distillations because my crappy water soluble, highly polar, small compounds are a nightmare to purify.
Although I do love a kugelrohr distillation, my life saving (and by that I mean post-doc saving) piece of equipment this year has been the Soxhlet extractor. Unlike the kugelrohr apparatus, the Soxhlet was named after someone and that someone was Franz Ritter von Soxhlet, an agricultural chemist from Germany.
I use Soxhlet extractors to extract my precious product from a solid because I can’t use aqueous extraction methods. I put the solid from my reaction (usually a reduction using LAH) in to the filter paper-like “thimble”. THF is then put in the round bottom flask and heated up so it boils. The THF is then condensed into the thimble using a condenser. When the thimble is full, it drains back down in to the round bottomed flask and the process repeats. Any one that follows me on twitter will know that I am frequently mesmerised by this process. You can see it for yourself on the multitude of youtube videos.
I should also say that @SellaTheChemist does a much better job of explaining this over at his RSC Classic Kit blog.
Today is my official last day of my current postdoc so I thought I would celebrate the piece of equipment that got me though. Thanks Franz Ritter von Soxhlet for making this postdoc more than bearable!
An excellent piece of equipment and technique which I used a lot over the years in food and pharmaceutical analysis. For my MPhil project, I used the Likens-Nickerson extractor, which is well-worth trying http://www.scribd.com/doc/61910559/121/Likens-and-Nickerson-SDE-Method
If only there had been someone called Kugelrohr I would have written about him. But if there had been, his childhood would have been a nightmare” anyone called “ball-tube” would have got no end of ribbing in school.
Good luck in your next position!
I love wikipedia’s gif for the soxhlet in action. It’s mesmerizing.
Pingback: #Realtimechemcarnival: Monday Musings | The Organic Solution