HS 55 (Batch Mode)
Function and design
15
Remove the reaction beaker after the measuring process, rinse it and refill it with sam-
ple.
4-valve group
Purge gas
1-channel hose pump
Reduction agent
Cell
(in the AAS)
Gold collector
Solenoid
valve
Drying
hose
Gas outlet
Transport gas
Reaction beaker
Figure 3 Functional diagram
The Hg/hydride system normally works with sodium borohydride (NaBH
4
) as the reduc-
tion agent. Alternatively, you can use tin(II) chloride (SnCl
2
) for Hg detection.
NOTICE
High workload when changing the reduction agent
Changing the reduction agent requires major maintenance work.
¡
Renew all hoses that have come into contact with the reduction agent.
¡
Flush the Hg/hydride system thoroughly before loading samples the next time.
3.2.1
Hose pump
The 1-channel hose pump is equipped with an adjustable snap-in cartridge and an
Ismaprene pump hose with an inner diameter of 2.06 mm. The pump only runs during
the pump time and transports reduction agent in 4 selectable speed stages.
3.2.2
Batch module
The batch module consists of a reaction beaker with a conical bottom for sample vol-
umes of 1 to 20 ml and the head.
The head contains:
¡
purge gas supply (marked "purge gas" at the head), argon gas flow 15 l/h
¡
transport gas supply (marked "transp. gas"), argon gas flows 6 l/h and 25 l/h
¡
gas outlet to the cell (marked "to cell")
¡
flange seal for reaction beaker
¡
Metering tip