Dear visitor, this is a machine-translated article. It makes perfect sense in its original language (Czech), and is fully backed by independent scientific literature. The translation, though, is far from perfect and takes patience and imagination, if you decide to read it.

Drobečková navigace

How to use Soxhlet's Extractor II?

Hello please advise on how to use Soxhlet's extractor or any reference to the instructions I am dealing with extracting different plants in solvent alcohol or gasoline in advance Thank you for some advice Petr B.

Dear Mr. Peter,

Optical physicists say it is either very easy or, on the contrary, very difficult. The same can be said in extraction chemistry. The practice of enzymology at the Charles University is the most difficult and expensive practitioner of the whole study, and in large part is devoted to extraction. Many scientists have spent their life trying to extract and crystallize substances from plant and animal materials. On the other hand, simple extraction can be done easily by simply inserting the plant material into the solvent container. I would call this a batch extraction procedure. In the case of quantitative extraction of 100% of the content of the substance, it is possible to use countercurrent or batch-counter extraction, such as used in skin tanning. Its description is indicated here .

From a practical point of view, Soxhlet's extractor stands somewhere between the batch and column extractions. It is characterized by the recycling of the solvent, which takes place by distillation and re-condensation on the cooler over the charcoal cartridge. Some qualitative factors influencing extraction on a sox-hole are qualitatively described in another answer , but I do not pay attention to the half-time mode in which the right Soxhlet works. The right Soxhlet has a tube that ensures that the cartridge is gradually filled with a condensing solvent and when it is fully filled, the drain tube is overheated and the contents of the cartridge are emptied into the warming flask. I could now refer you to the resources you would study by learning how to calculate the extraction length and its other parameters. About these resources, you can make an idea of this for the useless use of the "Chemical Engineering, Chapter Extraction " syllabus, freely available on the Internet. However, you would have to test the constants for the calculation.

So you do not avoid attempts (and mistakes), whether with mathematics or without it. If you want to extrapolate to the Americas, that is without mathematics, do the following: Let's say you have Soxhlet with a five-liter volume of the extraction vessel. Sprinkle into a patron about a kilo of plant material grated to grains of a maximum of 5 mm (the seeds must be crushed even if they are like poppy seeds) or slices of a thickness of up to 3 mm. Pour as much solvent as possible so that the material is overlapped, but do not spin the solvent into the bottom of the sox-bottle (you will need about four liters of solvent). Close Soxhlet and allow for a few hours to swell at room temperature. Then add a little solvent to soak up the bottling tube and drain the solution into the lower container. The plant material should now be bent and its volume should be increased. Drugs swell in different ways - just a few percent of the trees, about three times, some fruits even more than five times. It is in your interest to use that amount so that the bulk drug will fill the cartridge about 90%. The drug usually ingests a considerable amount of solvent, and so much less than 4 liters is rolled into the bottom vessel. Now take a fresh dose of fresh solvent and pour the cartridge one more time just below the edge (now there is a drug in it, so the solvents will fit less). Allow two more hours to leach at room temperature, then turn on the extractor for low power (ie heating and cooler). When boiling in the bottom vessel, the condensing extract soon overflows the bottling tube so that the remainder of the solvent runs into the bottom vessel. Increase the extractor's performance to the working value (ie the highest one that works smoothly), stay with him, watch the filling with the distillate and count the number of turns. When the extractor turns four times, the extraction should be done roughly. This is the point in which most of the people do not pay to waste energy and harass the drug by further heating to conquer the remaining about 3% of the soluble substances remaining in the cake. You should now own something between 2-7 liters of extract, to which more than 90% of the substances that can be obtained from the herbal drug by the solvent are transferred to the extraction.

Of course, gasoline can not be used amateurally for extraction for food purposes. Take extra care to ensure that the cooler has condensed the solvent in a quantitative way, and spirits or even petrol vapor have not escaped into the environment. Take personal care of the extraction and always use a sufficient amount of solvent to avoid drying the heating container. Always work with gasoline only outside in fresh air. Do not eat, drink alcohol or alcohol extract in excess of small quantities, do not smoke and do not handle with open fire. Legal Addition: I avail myself of any liability for damage to property and property caused by the explosion of alcohol or gasoline.

-boris-

| 16.11.2010

Related articles