AZURA® Assistant ASM 2.2L Instructions V6803
Chemical compatibility of wetted materials 47
17. Chemical compatibility of
wetted materials
Note:
The user takes the responsibility for using the fluids and chemicals
in an appropriate and safe way. If there is any doubt, contact the techni-
cal support of the manufacturer.
17.1 General
The device is very resistant against a variety of commonly used eluents.
However, make sure that no eluents or water come in contact with the
device or enter into the device. Some organic solvents (such as chlori-
nated hydrocarbons, ether) may cause coating damage or loosen glued
components by improper handling. Even small quantities of other sub-
stances, such as additives, modifiers, or salts can influence the durability
of the materials. Exposure time and concentration have a high impact on
the resistance.
The following list contains information about the chemical compatibility
of all wetted materials which are used in devices made by KNAUER. The
data bases on a literature research on the manufacturer specifications of
the materials. The wetted materials of this device are listed in the chapter
“Technical data”.
All resistances mentioned here are for use at temperatures up to 40 ° C,
unless stated otherwise. Please note that higher temperatures can signifi-
cantly affect the stability of different materials.
17.2 Plastics
Polyetheretherketone (PEEK)
PEEK is a durable and resistant plastic and, next to stainless steel, the
standard material in HPLC. It can be used at temperatures up to 100 °C
and is highly chemical resistant against almost all commonly used sol-
vents in a pH range of 1-12,5. PEEK is potentially moderate resistant
against oxidizing and reducing solvents.
Therefore, following solvents should not be used: Concentrated and oxi-
dizing acids (such as nitric acid solution, sulfuric acid), halogenated acids
(such as hydrofluoric acid, hydrobromic acid) and gaseous halogens.
Hydrochloric acid is approved for most applications.
In addition, following solvents can have a swelling effect and may have
an impact on the functionality of the built-in components: Methylene
chloride, THF and DMSO in any concentration such as acetonitrile in
higher concentrations.
Polyethylene terephthalate (PET, outdated PETP)
PET is a thermoplastic and semi-crystalline material with high wear
resistance. It is resistant against diluted acids, aliphatic and aromatic
hydrocarbons, oils, fats and alcohols, but not against halogenated hy-
drocarbons and ketones. Since PET belongs chemically to esters, it is not
compatible with inorganic acids, hot water and alkalis. Maximum operat-
ing Temperature: up to 120 °C.