soma_seeker

Hi, thank you very much for your response. I was fairly brief in the description of my process for the sake of brevity and because it is not something I wish to alter if possible. I'd like to leave the solid material in the system at this stage so that any diethyl ether soluble material will be extracted. By centrifuging, I produce a tri-layer system, the aqueous layer on the bottom, a solid 'disc' of material at the phase boundary and then the organic layer on top. I don't want to use DCM as it is more dense than water. Having the organic layer on top is very convenient for removing it, adding more, stirring up the solid material and repeating the process. I do have the ability to chill the centrifuge. What temperature range would you suggest? Do you think this will significantly reduce any explosion risks? Thanks again for your help.

Hi everyone, this is my first post here on your forums. Thanks in advance for your time. Ok, so I'm performing a hydrothermal liquefaction of lignocellulosic material in an aqueous (basic) solvent system. After performing the reaction I am left with an aqueous mixture of; - Solid starting material/char - Base-soluble breakdown products and starting material - Organic solvent soluble breakdown products and starting material I then wish to perform an extraction with diethyl ether (from previous work performed by others both within my lab and elsewhere, diethyl ether and dichloromethane are the only solvents capable of extracting a sufficient range of breakdown products). I've found that this forms a fairly stubborn emulsion and is further complicated by the presence of solid material (filtering the solids prior to extraction is not a convenient option). Ultimately I've devised a workup process that is extremely convenient but involves the centrifuging of diethyl ether, which I'm concerned will not pass the OH&S requirements of the lab. Dichloromethane is obviously safer, however being denser than water the workup procedure then becomes SIGNIFICANTLY less convenient that with diethyl ether. My question is, is centrifuging 50 mL screw-cap glass centrifuge tubes containing approximately 20 mL of aqueous solution and the same volume of diethyl ether a significant explosion risk/safety concern? Does the fact that the diethyl ether is water-saturated significantly reduce the risks involved? If the safety risk is in fact too high, can you suggest any ways in which I could reduce the risks involved without changing solvent? The workup process is so ideal as is that I have even considered looking into a hand-operated bench-top centrifuge (although so far I've only found such instruments that can handle 15mL sample vials). Thanks very much for any assistance you can offer.