There's an article in today's Inside Higher Ed on the building momentum in college chemistry courses to make the labs greener -- that is, to reduce the amount of hazardous materials necessary in the required student experiments. What grabbed me about the article is that it looks like the greening of the chem labs may not just be good for the environment -- it could be better for student learning, too.
First, consider a chemist's description of how to revamp laboratory experiments to make them greener. The article quotes Ken Doxsee, a chemistry professor at University of Oregon:
"We look at a chemical reaction or a chemical process. We look at everything that goes into it, whether it's a starting material or a reagent or a solvent or materials to run the reaction in, and we look at everything that comes out, which is what you want, and any byproduct, and consider each of those things as something where you ought to think about health and safety and the environment," says Doxsee, who, with [Professor James E.] Hutchison, leads National Science Foundation-funded summer workshops in green chemistry education at Oregon.
"If you're making a byproduct, do you have to? If you're using a solvent, do you have to?...If you start with two reactants, do you incorporate both of them in your product or does 50 percent of one of them get thrown away as waste? If you have to start with a material, does it require you to isolate it from petroleum, or can you get it from a renewable source?" asks Doxsee.
"Basically, that's what the green principles say, is to look at everything and make sure you're being smart."
There are lots of good "bottom-line" reasons to modify experiments this way: you can run labs in spaces without lots of fume hoods, save money on hazardous waste disposal, possibly avoid worries about legal liability from a student getting hurt (I know! but don't underestimate the power of a university legal team in shaping the options available to you), and maybe lose less sleep over DHS regulated chemicals and the paperwork they'll necessitate.
But here's where I though the article got really interesting:
In those pockets where green chemistry is happening in the university laboratory, innovation and energy levels are high. Thomas Goodwin, a professor of chemistry at Hendrix, describes for instance adapting a reaction described in the Journal of Chemical Education. Unhappy with the use of toluene, a petrochemical solvent, as the literature called for, Goodwin and a student tried running the experiment without the solvent, just to see if it worked. It did.
Then, they decided to lower the temperature called for in the literature: Rather than running the reaction at 90 degrees Celsius, "We said, 'Let's just mix these two things together at room temperature -- and it also worked." That was a particularly unusual reaction to have worked in that combination of circumstances, Goodwin conceded - "But we never would have tried these things" without a green ethos.
Notice what's happening here? Rather than sticking to a well-established cookbook approach to the experiment, Goodwin and his student violated the recipe (in a systematic way) to see what would happen. If you're inclined to think (as I do) that messing around with recipes is more likely to produce understanding of the outcomes of laboratory experimentation, this is a cool side effect of the bottom-line decision to go greener.
Indeed, it seems to me that this is a place in the revamping of laboratory curricula where a significant opportunity presents itself.
Rather than rewriting the "cookbook" as it were, to replace the old-school experimental protocols with new greener ones, why not have students take the old recipes and use the principles of green chemistry as a constraint in working out new protocols themselves? (Of course, there would be additional guidance from their lab instructors as to the reagents available in the stockroom, some basic experimental techniques, and so on.) The extent to which real learning could take place -- in part, because the lab instructor doesn't have a canned "right outcome" that the students must aim for -- is huge, and the knowledge the students produce in their labs might actually be novel (publishable, even) and useful to other people.
Is anyone doing this with their own students? It would be cool to get some reports from the lab bench.
Another benefit may be that controlling your chemistry makes for better quality and higher purity.
For example, when I worked on semiconductor materials the traditional clean was three solvents in series which each added particles. Out in the industry that wasn't acceptable, so various chemistries replaced it. The greenest, chemically if not energetically, was supercritical carbon dioxide. AFAIK it allows virtually full control of added particulates, i.e. high quality of the end product.
This statement jumped out at me:
we never would have tried these things without a green ethos
That's exactly why the tag line of one of my web sites says, "Sustainability is an attitude". And that's why I write a lot more about attitude, behavior, and culture than I do about composting and recycling.
Sustainability is all about attitude, and we will never try the things that we really need to do without a green ethos.
Thanks for sharing this with your readers.