Liner And/Or Insert Care; Glass Inserts - HP 5890 Series II Plus Reference Manual

Preventive Maintenance

Liner and/or insert care

Liner and/or insert care
Regardless of the inlet system, inlet inserts and/or liners must be kept
clean for optimum performance, particularly their interiors from which
contamination may enter the column and/or interact with sample
components.
Note: Excessive contamination anywhere on an insert or liner should be
avoided, particularly its interior.
Ideally, clean replacement liners and/or inserts should be available for
quick exchange when necessary.
Liners and/or inserts are treated differently, depending upon whether
they are of glass or metal.

Glass inserts

If a split insert (for a split/splitless, or split•only , capillary inlet
system) is to be cleaned, remove its packing.
Because contamination is often in the form of carbonaceous materials
(insoluble in organic solvents), immersion in concentrated chromic
acid (for up to 24 hours) is recommended as the first cleaning step.
Concentrated chromic acid is highly toxic and corrosive. Observe proper
WARNING
safety precautions.
After chromic acid, inserts are rinsed in distilled H O, CH OH
(methanol) and (CH ) CO (acetone), and then dried thoroughly in an
oven at 105 C.
After washing and drying, a small brush or suitable wire may be used
to dislodge solids from interior surfaces, followed by using
compressed, filtered, dry air or N to blow any loose material out of
the insert.
Finally, the glass surface should be deactivated using any
recommended procedure.
169