What are the advantages of using a Soxhlet extractor?
There are two advantages: economy of labour and economy of materials.
Here is a picture of a Wiley or Soxhlet extractor in operation.
The acetone is heated to reflux. Its vapours travel up a side arm.
The condenser cools the acetone vapour back to a liquid. The acetone drips down into the chamber containing the thimble of meat.
The chamber slowly fills with warm acetone. Some of the fat dissolves in the warm acetone.
When the chamber is almost full, it empties automatically by a siphon action. The acetone returns to the distillation flask, where it is re-used.
This cycle may be repeated many times, over hours or days.
The cycling process is automatic. This is the first advantage: once you have set it in operation, you can do other things and just check it occasionally.
After many cycles the fat from the meat is concentrated in the distillation flask.
The second advantage of this system is that instead of many portions of warm acetone being passed through the meat, just one batch of acetone is recycled.