what is the approximate weight of stationary phase

[jiang295]

for example in 4.6*25mm column, how much is the weight of whole stationary phase?
Thanks a lot.

[mardexis]

Let me get a napkin and a pencil first. Let's see...
Say 4 umole/gram & 300 m^2/gram & 1 g/mL & 0.5 mL gives 600 umole
if C18 then MW is around 300 g/mole which gives 180 mg.

You could probably find a better answer in Ewe Neue's book but I think
this might be pretty close. Biggest assumption was that density of empty packing is 1 g/mL and using the 0.5 mL empty column volume.

[Victor]

The volume of the empty column is 2.5 x pye x 0.23^2 =~ 0.416 mL

I got the following densities for Kromasil 100 A packings

Packed density:
SIL: 0.50 g/ml
C4: 0.57 g/ml
C8: 0.60 g/ml
C18: 0.66 g/ml
NH2: 0.53 g/ml
Phenyl: 0.59 g/ml

So if you choose for example the C18 packing (0.66 g/mL) you get about 0.27 g of packing in the column.

Did you really mean a 25mm column-this is possible but very short. If you really meant a 25cm column then you will have 2.7g of packing.

[jiang295]

thanks , i mean 250mm.
thanks a lot.

The volume of the empty column is 2.5 x pye x 0.23^2 =~ 0.416 mL

I got the following densities for Kromasil 100 A packings

Packed density:
SIL: 0.50 g/ml
C4: 0.57 g/ml
C8: 0.60 g/ml
C1
NH2: 0.53 g/ml
Phenyl: 0.59 g/ml

So if you choose for example the C18 packing (0.66 g/mL) you get about 0.27 g of packing in the column.

Did you really mean a 25mm column-this is possible but very short. If you really meant a 25cm column then you will have 2.7g of packing.

[weds1]

thanks for the post and reply ^_^