Unit 7.6 Recycling Aluminum
This unit deals with the uses of aluminum and efforts to
recycle it. In the classroom students learn the chemistry
of recycling aluminum cans to form alum.
Video program cues: 40:05-57:30
Aluminum or platinum?
"When the Washington Monument was originally
built, the debate was whether to get an aluminum cap or
a platinum cap. And since all students know that and recognize
that, we go cross-curriculum into American history of that
time. That gets them back to why were aluminum (which for
them is a wrapping that you drop) and platinum (which is
considered something wonderful) considered on par with each
other. And we get back to what it was like at that time,
what was the state of chemistry and the available knowledge
around the world at that time, and what you could think
is absolutely true: aluminum is rare, difficult, impossible
to use, but suddenly becomes totally different. We talk
about the economic effect because I believe the cap was
taken off during WW2 with aluminum scrapes on it, and the
effect that it would have if we had a platinum cap on there
now. They made this simple decision because it was going
to cost them the same, either way."
Annandale High School, Virginia
Craig, N.C. (1997)' ACS National Historic Chemical Landmark:
Charles Martin Hall's Discovery of the Electrochemical Process
for Aluminum, 'Journal of Chemical Education, Vol.
74, No. 11, pp: 1269.
Aluminum recycling laboratory
Al DeGennaro teaches about chemical recycling, by making
alum from aluminum soda cans.
Orecchio, S. (2001)' Recovery and Reutilization of Waste
Matter from Coffee Preparation. An Experiment for Environmental
Science Courses, 'Journal of Chemical Education,
Vol. 78, No. 12, pp: 1669-1671.
New composite materials
"These are actually the very first composite
materials that we made with soybeans. This is part of a
round-tape bailer that was made up for John Deere. To mass-produce
these, we worked with several fabricators on the outside,
and these are currently being used. John Deere currently
switches from metal based blades to composite material blades,
and the possibility of using the farmers own soybeans
to make combined harvesters from their own products is very
"There are several reasons why people
are attracted to these materials. From a fundamental property
point of view, they are pretty much the same as petroleum
based materials. They do have some exceptional impact resistance.
But I think most importantly, these materials are very environmentally
friendly; they are made from renewable resources. When you
look to the future, and you run out of oil in 70 years,
and of natural gas in 80 years, you would like to maintain
your life-style, affordably, with low-cost, sustainable
materials this is a real vision of the future."
Dr. Richard Wool
Professor of Chemical Engineering, University of Delaware
"Kids naturally gravitate to this
topic, so we usually pick a few labs during the course of
first year chemistry and have them either go out to get
and analyze samples, or have discussions on these topics
and come up with their interest in acid rain. When they
get into acid-base chemistry, we talk about the misconceptions
that they have. They have no idea where it comes from or
what the causes are. How environmental protection aspects
either influence or do not influence air quality. They are
totally unaware, and they have no idea that the air is much
cleaner than it was 10-20 years ago. And impacts like that.
So these topics are really easy to get into, almost any
unit that you do in chemistry. The kids actually come up
with these questions, and if they dont, you make sure
that they have them."
Thomas Edison High School, Virginia
McGowin, Audrey E.; Hess, George G. (1999)' Incorporation
of GC-MS into an Environmental Science Curriculum, 'Journal
of Chemical Education, Vol. 76, No. 1, pp: 23-24.
Are we a sustainable civilization?
"At the introduction to my lectures, I always
ask my audience: Do you think that we live in a sustainable
civilization? I have asked almost three thousand people
this question, including the scientific intelligence leadership
of the world, and nobody has raised their hands and said
that we live in a sustainable civilization. As you peel
the time back they say that we might only be sustainable
for decades. This is clearly something very, very central
to our future, and the really exciting thing about it is
that chemistry is really big in this. Chemistry can do wonderful
things, as it has already done, for humanity. We reflect
so much on the negative things, but it has done so many
wonderful things, that its also central to our continued
Dr. Terry Collins
Professor of Chemistry, Carnegie Mellon University
to Workshop 8