To ensure a homogeneous eluent concentration, the carbonate eluent generated by the Dionex EGC 500 K2CO3 flows through a Dionex EGC 500 Carbonate Mixer before being delivered to the injection valve. The mixer is included in the following kits:

  • Dionex EGC 500 Carbonate Mixer Kit, 2 mm (P/N 088467)
  • Dionex EGC 500 Carbonate Mixer Kit, 4 mm (P/N 088468)

Eluent flows through the Load or Inject path, depending on the valve position.

  • Load position: Sample is loaded into the sample loop, where it is held until injection. Eluent flows from the pump, through the valve, and to the column, bypassing the sample loop. Sample flows from the syringe or automated sampler line (if installed), through the valve, and into the sample loop. Excess sample flows out to waste.
  • Inject position: Sample is swept to the column for analysis. Eluent flows from the pump, through the sample loop, and on to the column, carrying the contents of the sample loop with it. See Injection valve for the injection valve connections. The injection valve is plumbed at the factory with all tubing and fittings for connection to the pump, injection port, column, and waste. A 25-μL PEEK (polyether ether ketone) sample loop (P/N 042857) is installed between ports L (1) and L (4). If necessary, replace the pre-installed 25-μL loop with a loop that has a different sample injection volume. Thermo Fisher Scientific offers sample loops in various sizes.