Video and Research Highlight: Dissolving cellulose in ionic liquids for biofuels
If you’re following me on twitter or G+, you might have seen that I wrote another research highlight for the Daily Cardinal this week, this time focusing on a new biofuels start-up company here in Wisconsin.
The company, co-founded by UW-Madison biochemistry professor Ron Raines, is developing a process for dissolving cellulose in ionic liquids and converting it into useful sugars that can be used as feedstocks for other chemical processes (like conversion to ethanol, octane, or precursors for materials syntheses).
I’ve mostly described the chemistry in the article, but I wanted to post a cool video here that’s related to this research:
This is a video of a cotton ball being dissolved in an ionic liquid. Cotton is more than 90% celllulose, and it’s not something we usually think of as easy to dissolve. Yet this ionic liquid pulls it apart in a matter of seconds. How???
The key is that the strands of sugar that make up cellulose are held together by a ton of hydrogen bonds. The oxygen and hydrogen atoms in the sugars have slight negative and positive charges, which attract each other and cause neighboring strands to stick together.
This ionic liquid, on the other hand, contains a high concentration of chloride ions, which are free to roam around (unlike, say, the chloride ions in a solution of table salt in water – in that case, the chloride ions are more interested in interacting with the water than with anything else). These chloride ions are also very negatively charged, and they can disrupt the hydrogen bond interactions holding together the cellulose strands.
As a result, when you drop cellulose into this ionic liquid, poof – there it goes! Into solution, and ready for you to do chemistry on it.
I think that’s pretty cool, don’t you?
If you’re interested, the research described in this highlight comes from this PNAS paper. It’s even open access, so you can read the whole thing if you are so inclined!