> If you used a variable reflux ratio distilling head
> couldn't you duplicate the conditions outlined in their
> rating? For example, they will tell you that at x mL/hr
> you will get y amount of theoretical plates.
Yes you could, if they tell you the necessary reflux ratio and throughput, and you manage to reproduce them.
Big ass columns and distillation heads etc. are meant for solvent purification where column holdup and amount of forerun don't matter, not for 50-100g ketone distillations.
They are great to turn used or lower grade solvents into reagent grade or spectroscopy grade, where the difference between 99.5 and 99.8% purity and absence of specific compounds is important.
For our purposes it doesn't really matter if the ketone is 98.3 or 99.5% pure, it certainly isn't worth the huge difference in money and time necessary to convert the former into the latter.
If you have to distill a liter of ketone every other week, and have enough privacy to let that thing run for several days then go ahead and don't let me stop you.
Otherwise that time and money could be used more effectively to clean up your products.
> How would you propose doing that? Just use a regular
> distillation column w/ packing?
Yes.
> If so, what kind of packing?
Depends on many factors. Crushed glass, glass balls, rolled wire mesh, commercially available column filling. Depends on column size, required th. plates, throughput, OTC or not, cost, vacuum or no vacuum distillation, batch size etc.
> And wouldn't it be pretty hard to know how many
> theoretical plates you are getting?
Yes. But you can guesstimate it by consulting tables and formulas, and eventually checking the distillate by GC or any other means and see how pure your product is. Who cares if you achieved 11.5 or 13.2 theoretical plates, as long as the result is ok and repeatable all is well.
> Why would the textbook give these numbers if even some
> bees say that using a still head (1 theoretical plate) is
> good enough?
Those bees don't know what they are talking about.
A stillhead is often better than one th.pl.
I'm not fat just horizontally disproportionate.