beautypg.com

Metrohm 887 Professional UV/VIS Detector User Manual

Page 40

background image

6.6 Cleaning the flow-through cell

■■■■■■■■■■■■■■■■■■■■■■

32

■■■■■■■■

887 Professional UV/VIS Detector

Rinsing the flow-through cell with methanol

1 Disconnect the inlet capillary from the IC system.

2 Connect the inlet capillary to a high pressure pump or a peristaltic

pump and rinse the flow-through cell as follows – ensure that the
maximum pressure of 5 MPa is not exceeded:

first, rinse with ultrapure water to avoid precipitation,

then, rinse several minutes with methanol, to dissolve the depos-
its, and

finally, rinse another 15 minutes with ultrapure water, to wash
away the dissolved deposits.

3 Observe the baseline during the last rinsing step.

If the baseline remains flat, the flow-through cell is clean.

If the noise persists, rinse the flow-through cell once again with
another solvent (see "Rinsing the flow-through cell with another sol-
vent", page 32)
.

Rinsing the flow-through cell with another solvent

A solvent made up of a 1:2 mixture of acetic acid and isopropanol has
shown good results. Depending on the application, other solvents may
also prove efficient.

Preconditions:

Rinsing with methanol was inefficient.

The inlet capillary is connected to a high pressure pump or a peristaltic
pump.

1 Rinse the flow-through cell as follows – ensure that the maximum

pressure of 5MPa is not exceeded:

first, rinse with ultrapure water to avoid precipitation,

then, rinse several minutes with the selected solvent to dissolve
the deposits, and

finally, rinse another 15 minutes with ultrapure water to wash
away the dissolved deposits.

2 Observe the baseline during the last rinsing step.

If the baseline remains flat, the flow-through cell is clean.