I am using DMSO,water-IL and solid catalyst to synthesize HMF and managed to extract most of it from reaction media with diethyl ether.Following this,I am left with the spent catalyst+ionic liquid in my aqueous phase along with DMSO. My overall sample volume is just 10ml but the absence of relatively high vacuum pump makes it difficult to distill out DMSO from the media.Can fractional crystallization help to get most of the water phase back?
If so,how.Can anyone provide some reference.
DMSO forms with anhydrous CaCl2 insoluble complex which can be separated by filtration.
Pavel Pazdera- Can you provide me some reference for this work!It sounds interesting.
DMSO-heptane-water triple azeothrope is helping hand if high vaccuum is not accessible. http://sci-hub.org/10.1080/00397918708063982 (temporary link) , citation link http://www.tandfonline.com/doi/abs/10.1080/00397918708063982?journalCode=lsyc20
Hello Shrestha,
I am intrigued by your experimental combinations. In the crystallization-science, your experiment falls under the category of anti-solvent precipitations, one of the ‘Three-Sisters of precipitation’. In this procedure, an anti-solvent is added to a solution using another solvent. The solvent and anti-solvent must by miscible. The solute must not be soluble in the anti-solvent. When the anti-solvent is added, the solvent mixes with it, and the solute is deprived of the solvent. This leads to an increased concentration, and a critical ratio of solvent and anti-solvent, and the solute precipitates.
Chapter 4: Sister-3 Anti-Solvent Crystallization; Three-Sister Model for Controlled Crystallization
https://www.researchgate.net/profile/Ingo_Leubner/publication/272237589_Three-Sisters_Model_Chapter_4_Anti-Solvent_Precipitations/links/54dfc93f0cf24d184b0a45c7.pdf?origin=publication_detail
DOI: 10.13140/2.1.2211.9200
The mechanistic, and concept and suggested precipitation procedures, are related to the above model and the theory is based the model.
I am hoping that it will help you to get your precipitation under control. If you monitor your procedures, your process will scale up efficiently. Check the manuscript above.
Good success, Ingo H. Leubner, Dr. rer.nat.
Technical Report Three-Sisters Model, Chapter 4: Anti-Solvent Precipitations
Since you are already using liquid-liquid extraction with diethyl ether, apparently from an ionic liquid (IL) aqueous solution, if I correctly understood the question, I think that you try to exploit to the maximum reasonable extent the ability of the diethyl ether (Et2O) to extract the dimethyl sulfoxide (DMSO) from the aqueous solution. For instance, it would be more efficient to repeat the extraction stage by a number of times with limited quantities of Et2O, rather than using the equivalent overall quantity of solvent on a single stage. Moreover, the solubility of the DMSO and of the Et2O in the aqueous solution may possibly be reduced by the addition of some convenient additive (miscible/soluble with/in the IL but having low affinity for DMSO and Et2O), by increasing the concentration of the IL used, and/or by judiciously selecting the extraction operation temperature. You may them possibly find that the potential of liquid-liquid extraction by Et2O to quantitatively remove DMSO from the reaction media can be extended. Eventually, it may be enough to accomplish a satisfactory threshold, without the need for a subsequent method to be considered.
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