Agilent Technologies G4782A, Руководство пользователя

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50 1260 SFC Binary Pump
3
Using the Pump
Solvent Information
This is due to a thin oxide layer on the surface, which is stabilized by oxidizing
compounds. Non-oxidizing acids (for example, hydrochloric, sulfuric and
phosphoric acid) can cause slight corrosion, which increases with acid
concentration and temperature. For example, the corrosion rate with 3 % HCl
(about pH 0.1) at room temperature is about 13 μm/year. At room
temperature, titanium is resistant to concentrations of about 5 % sulfuric acid
(about pH 0.3). Addition of nitric acid to hydrochloric or sulfuric acids
significantly reduces corrosion rates. Titanium is sensitive to acidic metal
chlorides like FeCl
3
or CuCl
2
. Titanium is subject to corrosion in anhydrous
methanol, which can be avoided by adding a small amount of water (about
3 %). Slight corrosion is possible with ammonia > 10 %.
Diamond-Like Carbon (DLC)
Diamond-Like Carbon is inert to almost all common acids, bases and solvents.
There are no documented incompatibilities for HPLC applications.
Fused silica and Quartz (SiO
2
)
Fused silica is used in 1290 Infinity Flow Cells and capillaries. Quartz is used
for classical flow cell windows. It is inert against all common solvents and
acids except hydrofluoric acid and acidic solvents containing fluorides. It is
corroded by strong bases and should not be used above pH 12 at room
temperature. The corrosion of flow cell windows can negatively affect
measurement results. For a pH greater than 12, the use of flow cells with
sapphire windows is recommended.
Gold
Gold is inert to all common HPLC solvents, acids and bases within the
specified pH range. It can be corroded by complexing cyanides and
concentrated acids like aqua regia.
Zirconium Oxide (ZrO
2
)
Zirconium Oxide is inert to almost all common acids, bases and solvents.
There are no documented incompatibilities for HPLC applications.