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Sheri Lense, University of Wisconsin Oshkosh
Last seen: 4 months 1 week ago
Joined: 10/11/2012 - 11:31am

Greener and Less Toxic Solvents for an IR Spectroscopy Lab


When an upper-level class I am teaching this semester was run previously, students did a lab where they looked at the relationship between sample concentration and hydrogen bonding.  They made solutions of cyclohexanol in carbon tetrachloride and used a solution cell with NaCl windows when recording their spectra.  I would like to do a lab this semester where the class explores replacing carbon tetrachloride with less toxic and greener solvents.  (I will also replace the cyclohexanol with a different alcohol.)  My idea is that they will assess the spectra produced in the different solvents in both the O-H stretching region and the fingerprint region, with solvent choice being more problematic in the latter region. I'm hoping for some more ideas for solvents that aren't quite as bad as CCl4.  So far I have methylene chloride (not great, I know, but better than CCl4).  I am also going to look at 1,1,1-trichloroethane (again, not great) and maybe a longer chain hydrocarbon, such as heptane, for them to try.  I'd like to stear clear of mineral oil because of the difficult in cleaning the cell.  Thank you in advance!