Tutorial

You will find below, how to replicate yourself the basic CFR experiment, in a next article, I shall explain you how to replicate an enhanced version of the CFR:

The CFR is composed of borosilicate beaker filled with a 600 mL to 800 mL of demineralized water and Potassium Carbonate ( K2CO3 ), the electrolyte solution commonly used is 0.5 molar ( 0.5 M, ).

For the Potassium Carbonate ( K2CO3 ) : 
The weight of 1 Mole is 138.2 g. If you want to have a 0.5 molar solution ( 0.5 M or 0.5 mole/L ).
For 1 liter, you need to add : 0.5 * 138.2 * 1 = 69.1 g of K2CO3
i.e : For 800 mL of demineralized water. 
So, to get a 0.5 M solution of electrolyte, I need to add : 0.5 * 138.2 * 0.8 = 55.3 g of K2CO3

The Cathode used is a tungsten rod. The tungsten rod can be a pure tungsten rod or a Th-loaded WT20 (with ThO2: 1.70-2.20% ) from tungsten TIG electrodes (WT20) commonly used forTIG and Plasma welding. The use of a Th-loaded rod increase the life of your cathod. The sputtering effect is lower with a Th-loaded rod than a pure tungsten rod produced by the thermoionic emission by the use of the thorium oxide.

The rod diameter can be between 3 mm to 6 mm diameter and 150 mm length . The Anode used is composed of stainless steel mesh ( a grid ) maintained with a stainless steel  rods. If you have planned to conduct some chemical analysis, I recommend you to use a grid made with platinum or nickel . All the wires connections are made with a 1.5 mm2 copper flexible wire gained with silicon.

I also recommend you to put anti-strips disks below the reactor, this will avoid that the reactor moves on your test bench due to the strong vibrations produced during the plasma ignition sequence.

To avoid projections of some drops of the electrolyte solution from the CFR during the plasma ignition sequence, I recommend you to put floating balls on the surface of the liquid (hollow floating balls; pp, 20mm, 2000 PK from Cole Parmer Instrument )