Product News: New Product release... 874 USB Oven Sample Processor

17 Jun 2009

The 874 Oven Sample Processor is used for thermal sample preparation in Karl Fischer titration. The oven method is suitable for samples that only release their moisture at higher temperature, for hardly soluble samples or samples that undergo side-reactions with the KF reagent.

• USB device – If the 874 USB Oven Sample Processor is connected to a PC the instrument is recognized automatically.
• Optimal oven temperature – Running a temperature gradient the optimal oven temperature for every sample can be defined
• Reagent exchange – 800 Dosinos can be attached to one of the MSB ports of the Sample Changer. With a Dosino and a Dosing unit the reagent exchange can be done automatically

Sample Changer for driving out the moisture contained in liquid or solid samples.

Oven method

The sample is weighed in a sample vial, tightly closed and placed on the rack. The sample is then heated up in the oven and the moisture evaporated. A double hollow needle pierces the septum and a dry carrier gas flow transports the moisture into the titration cell where the Karl Fischer titration takes place. A big advantage of the oven method is the fact that the sample itself is not introduced into the titration vessel. Contamination of the oven and the titration cell as well as side-reactions and matrix effects are eliminated.

Temperature gradient

What is the optimal oven temperature? This is an important question if unknown samples are to be analyzed. The oven temperature should be chosen as high as possible to ensure a fast evaporation of the moisture and a quick transport into the titration cell. But the sample should not start to decompose as the products of decomposition would falsify the results. The 874 USB Oven Sample Processor offers you the possibility to subject the unknown sample to a temperature gradient. The optimal oven temperature can be then be defined based on the resulting heating curve.

Reagent exchange

Besides a stirrer also Dosinos and Dosing Units can be attached to the 874. Thus it is possible to aspirate spent reagent and add fresh solvent automatically. There is no need to open the cell which means that no additional moisture enters the cell. This shortens conditioning and saves precious time. Furthermore the Dosino can be used to add auxiliary solutions such as buffers or solubilizers.