Metrohm 831 with stirrer 821 and thermal printer
Identical in construction to Metrohm 756.
The coulometric Karl Fischer titration is a variant of the classic Karl Fischer method for determining water content.
In the coulometric Karl Fischer titration, the required iodine is generated directly in the electrolyte via an electrochemical process (using an "electronic burette"). There is a strict quantitative relationship between the amount of electrical charge and the amount of iodine generated, which is used for highly precise iodine dosing. Since the coulometric Karl Fischer method is an absolute determination, no titer needs to be determined. It is only necessary to ensure that the reaction generating the iodine proceeds with 100% current efficiency. This is the case with all currently available reagents. Endpoint indication is achieved voltammetrically by applying a constant alternating current to a double platinum electrode. This creates a voltage difference between the platinum wires, which decreases drastically in the presence of even the smallest amounts of free iodine. This phenomenon is used to determine the endpoint of the titration.
Scope of delivery:
KF Coulorimeter 831
Stirrer 728
Keyboard 831
Printer
Cables
Condition: Used, very good