Sciencemadness Discussion Board

type of column for liquid chormatography?

soma - 22-1-2017 at 03:09

Short and wide - or long and thin?

Advantages of using a burette?

I want to separate a 1 - 2 gram sample. I was thinking of using a 10 - 20 mm i.d. x 100 - 200 mm height and 30 grams of silica.


Chemetix - 22-1-2017 at 12:32

Long and thin as a general rule; but what do you want to separate? Not that the actual substance matters to me. Developing a method for a particular separation is no small task. Do you want isomeric separation or something less complicated such as separating two very different chemistries, polar and not so polar. How clean is the sample?
Is there a chromaphore you can use to make the detection?

The questions can continue, there are many variables to consider.

A burette with a glass wool plug at the bottom can work. As you can see, there's more to it than just the hardware.

phlogiston - 22-1-2017 at 15:28

Long and thin --> better separation
Wide and short --> higher capacity.

A burette is convenient for starting and stopping the process, which makes it easy to avoid letting the column run dry.