What are the differences between the XT10 and XT15 instruments?
The XT10 and XT15 look very similar and have much in common. For example, both perform high temperature, high pressure soxhlet-like extractions on up to 15 samples at a time. The kinetics of the extraction provide an extraction time of no more than an hour with the vast majority of samples. They both have the same foot print and both recycle the solvent. Finally, they both require a fresh water source, a drain and, of course, an electrical supply.
The area in which they are different is in the solvent insertion. With the XT15, the technician adds up to 500 ml of solvent to a port on the left side of the instrument prior to using the extractor. The solvent goes into a fresh solvent holding tank. He/she then places up to 15 samples into the extraction vessel and locks the vessel closed. Utilizing the instrument’s computer, he/she then sets the extraction solvent, extraction time and temperature and starts the process. When the extraction is started, the solvent automatically is inserted into the closed vessel of the instrument and the extraction begins. When the extraction is completed, about 97% of the solvent is recycled back into the holding tank, ready for the next extraction. The samples are then removed, dried and weighed.
The XT10 does not have a holding tank. When beginning an extraction, the technician pours the solvent into the vessel of the instrument, closes the vessel and begins the run. At the end of the extraction, the solvent is recycled to a container on the left side of the instrument, ready to use again.
Because the XT10 does involve some solvent exposure to the environment, most labs put this instrument in a hood while many XT15 users do not because the instrument is completely closed when the solvent is present. The XT15 allows quicker turnaround from run to run because the technician doesn’t have to wait for the vessel to cool before adding solvent, contrary to XT10. In addition, the exposure of the solvent with the XT10 means that the instrument tends to recycle a bit less of the solvent than does the XT15 – about 90%.