Processing Catalog - EMD Chemicals

Mesopores
Macropores
40
Chromolith® Prep Si
Increase in speed, efficiency and productivity
Chromolith® Prep monolithic stationary phases are
new ultra-pure silica phases that have special
properties resulting from their bimodal pore
structure. This structure is based on new “Sol-
Gel” technology and consists of macropores and
mesopores.
The mesopores, with an average diameter of
12 nm, form the fine porous structure of the
column interior and create a very large surface
area on which adsorption of the target compounds
occurs.
The large macropores, with a pore diameter
ranging from 3 µm, form a dense network of
pores and allow their high flow rate due to their
low resistance factor. The resulting excellent
accessibility of the mesopores (total porosity
Different application with Chromolith® Prep Si (100-25mm)
Separation at high flow rate
Sample: Toluene, Dimethylphthalate,
Dibutylphthalate
Column : Chromolith® Prep (100-25 mm)
Solvent: n-heptane/dioxane ( 80/20 v/v)
Flow rate 40 ml/min
Separation at different flow rates 40 and 390 ml/min
Flow rate 390 ml/min
> 80 %) ensures fast adsorption and desorption
kinetics because of the short diffusion length
inside the pores. This results in dramatically
reduced separation times and thus in a huge
increase in productivity.
To operate a monolithic column it is necessary
to ensure that no flow-through occurs in the
wall region. Therefore, the monolith is cladded
with a polymeric material (special PEEK) and can
be connected directly to any HPLC system and
used as a ready-to-use-column.
Specification of Chromolith® Prep Si
Macropores [µm] 3
Mesopores [nm] 12
Specific pore volume [ml/g] 1
Specific surface area [m2/g] 350
Packing density [g/ml] 0.2
Total porosity 0.8
Surface pH neutral
Iron [%] content no
Chromolith® Prep
columns can be
operated at a
flow rate of up
to 400 ml/min,
which is a tenfold
increase to that
of a comparable
column packed
with a non-monolithic
or a particulate
sorbent.