Ensure the most efficient sample preparation for demanding applications in residue and contaminant analysis. Expand your range of application with the multiple extraction methods of the Extraction System B-811.


Flexible and efficient

  • Soxhlet, Soxhlet Warm, Hot Extraction and Continuous Flow on the same instrument
  • Combine the benefits of Soxhlet and Randall extraction in one instrument
  • Reach the required detection limit thanks to 60% larger sample volume (LSV configuration)
  • Compatible with many solvents and samples


  • Contamination free instrument thanks to autoclavable parts
  • No alternating blank values thanks to elimination of residual effects
  • Better recoveries by drying under inert gas

Safe and compliant

  • Perfect observation of the process thanks to visible glass setup
  • Minimized solvent loss thanks to high performance condenser
  • Risk of burns reduced by effective shielding and heating control
  • Full compliance achieved using the Soxhlet mode



Automatic sequencing

The electronic unit controls the sequence of the three steps (extraction, rinsing, drying) of between one to four samples in parallel. No manual intervention is necessary after programming activity and the starting instructions have been completed.

Quicker execution of the extraction process

Two built-in heating sources per extraction location and optimal heat transfer permit the use of high-boiling point solvents. Moreover, control by means of the optical sensor makes it possible for the user to optimize the exchange of the solvent from a timing point of view, to increase the material exchange (analyte / solvent) and, at the same time, to economize the solvent consumption.
Extraction System B-811 / B-811 LSV

Better operating protection thanks to higher safety standards

Cooling water, level of solvent and heat source are directly monitored, the complete apparatus is specially produced to view complete tightness of joints while a protective shield provides an extra precaution.

Sample-compatible drying

In the case of heat-sensitive samples, the extract can be concentrated in a protective mode and oxidation-sensitive samples can additionally be extracted and dried in an inert gas atmosphere.

Sample purity is maintained at all times

All components in contact with the sample are inert so the possibility of contamination of the sample, or carry-over of additives to sealing membranes is eliminated.

Expert Advice

When is it recommended to work with a recirculating chiller?

When you use a solvent like petroleum ether, a recirculating chiller should be implemented if the tap water is warmer than 15 °C. The temperature difference between the boiling point of the solvent and the cooling water temperature should be 20 - 25 °C in order to achieve a good condensation of the solvent in the condenser and to keep a good solvent recovery.

What is the difference between the four extraction methods offered by the B-811?

Soxhlet Standard:
  • The sample is extracted in condensed solvent, which is regularly exchanged against fresh solvent.
Soxhlet Warm:
  • The sample is extracted in hot solvent, which is regularly exchanged against fresh solvent. This leads to faster extraction times compared to Soxhlet Standard.
Hot Extraction:
  • The sample is extracted in boiling solvent. The principle is comparable to extraction according to Randall or Goldfish.
Continuous Extraction:
  • The sample is rinsed with condensed solvent.

What is the use of the B-811 Large Sample Volume?

The basic idea of these glass parts is to offer our customer the possibility to work with larger amounts of sample to reach the required detection limit of the analytes. The main glass parts are expanded up to 60%.

Which safety features does the B-811 offer?

Cooling water monitoring:
  • If the cooling water is disconnected or the water flow is interrupted, all processes are stopped.
Tight system:
  • Solvent-resistant sealing materials and reliable workmanship produce a tight system. Large cooling surface of the cooler minimizing loss of solvent through evaporation and therefore damage of human and environment.
IR Heating:
  • After switching off the heating plate is cold within seconds.
Protective shields:
  • The infrangible shields protect the operator from injury.
Dry beaker monitoring:
  • If one of the beakers dry out during the extraction or rinsing process, the software turns off the related position automatically. The process of the other positions is not affected.

When is it recommended to work under a fume hood?

The B-811 offers under normal conditions (when the unit is adequately used and maintained in good condition) an excellent solvent recovery rate thanks to its high degree of tightness. This means that there is practically no loss of solvent vapors and that it is not necessary to work under a fume hood. However, when the cooling water temperature is not cold enough or when working with health hazardous solvent, we recommend that for safety reasons, the unit is placed in a fume hood.

What does "inert" mean?

In the B-811, the sample, the extract and the solvent only get in contact with inert materials; glass, PTFE (sealing systems) and Fluorez (membrane in the glass valve). Additionally the extraction and drying process can be performed in an inert gas atmosphere.

Which heating level is recommended?

The B-811 heating guide shows a list of common solvents and the recommended heating steps as well as the relationship of heating level, enthalpy of vaporization and boiling point.

Set of glass beakers

The beakers are specially designed for the BUCHI extraction units. The bottom of the beaker is perfectly plane, which gives excellent heat transfer. The lip of the beaker is manually polished to ensure the best tightness of the system.


B-811 LSV (large sample volume)

With the B-811 LSV (large sample volume) model it is possible to increase the sample size to reach the required detection limit of the analytes. The main glass parts are expanded up to 60%.


Recirculating chiller for B-811 / B-811 LSV

The temperature difference between the boiling point of the solvent and the cooling water temperature should be 20-25°C in order to achieve good condensation of the solvent in the condenser and to achieve a good solvent recovery throughout the extraction.

E: care@invitro.com.au
P: 1300 552 003