Metrohm 766 IC Sample Processor - Manual (Page 91)

4 Operation
766 IC Sample Processor
86
4.6.7 Method "Preconc"
Application
Preconcentration of samples with very low concentrations in an pre-
concentration column (trace analysis).
Interconnection
see Fig. 13
Installation of the preconcentration column
The preconcentration column, consisting of the 6.1006.200 Metrosep
Anion preconcentration cartridge and the 6.2828.010 glass cartridge
holder, is installed at the injection valve of the 733 IC Separation Center
instead of the sample loop (see Fig. 18). It is important to install the
sample inlet from the 766 IC Sample Processor at connection 2 of the
injection valve in order to run the preconcentration column for the en-
richment and the sample injection in the opposite direction. If a larger
sample throughput is desired, install the optionally available 6.1826.040
pump tubing (inner diameter 1.6 mm, flow ca. 3 mL/min) at the peristal-
tic pump of the 766 IC Sample Processor.
1 2
4 5
3 6
1 2
4 5
3 6
Fig. 18: Installation of the preconcentration column
Program of 766 IC Sample Processor
766 IC Sample Proc. 11111 5.766.0010
parameters
method Preconc
number of samples: rack
>start sequence
1 CTL:Rm: INIT
2 CTL:Rm: INJECT A 1
>sample sequence
1 SCN:Rm : Wait1
2 SCN:Rm : Pump1 ?
3 MOVE 1 : sample
4 LIFT: 1 : work mm
5 PUMP 1.1 : ON s
6 WAIT 60 s
7 CTL:Rm: FILL A 1
8 WAIT 120 s
9 PUMP 1.1 : OFF s
10 CTL:Rm: ZERO 1
11 CTL:Rm: INJECT A 1
− Report header with serial number and program ver-
sion
− Method name
− Number of samples to be processed (entire sample
rack)
− Initialize remote interface
− Switch injection valve A at 733 to "Inject"
− Waiting until 732 IC Det. sends signal on rem. line 3
− Waiting until 709 IC Pump runs
− Move needle to sample position
− Place lift with needle to working position
− Switch on pump at 766
− Waiting time 60 s
− Switch injection valve A at 733 to "Fill"
− Sample preconcentration during 120 s
(preconcentration time must be adapted)
− Switch off pump at 766
− Trigger autozero at 732 IC Detector
− Switch injection valve A at 733 to "Inject"
Waste Sample Sample Waste
Sample injection Preconcentration
IC column
Preconc. column
Eluent IC column Eluent