Behr-Labor behrotest ® Randall Extraction, 1 position

Hot extraction according to Randall – the quicker extraction method

Manual devices for hot extractions that are several time quicker than a customary Soxhlet extraction, incl. on set of extraction sleeves, 100 ml.

Boiling

During the first step, the extraction sleeve is with the sample in the vessel with the boiling extractant, like a tea bag in a cup with hot water. Most of the substance that is to be extracted enters the solution in this step and distributes itself in the solvent.

The upper part of the device acts simply like a reflux cooler; the condensate drips into the extraction sleeve and helps bring the substance into the solution.

Rinsing

In a second step, the extraction sleeve is pulled out of the sump. Extract still adheres to it; and there still might be substance in the sample that has not yet dissolved. The condensate from the cooler rinses the extract and little by little dissolves the undissolved parts.

If you wish to further process the extract, this means the extraction is complete at this stage. Otherwise, you remove the solvent in a third step.

Evaporation

When evaporating, close the return cock on the cooler, the condensate collects in the lower part of the cooler; you can reuse it for the next extraction. Thanks to the short routes of the device, the sample can be evaporated until it is virtually dry.

• Optimum safety with screwed extraction units
• Multi-position extraction units
• Each extraction sleeve with sample can be moved individually
• The user can lower and lift all extraction units with a lever together into the heating chamber
• Each heating position with separate temperature adjustment
• A compact device with short paths
• Low need of solvent
• Short extraction duration – typically about an hour.