Green chemistry. Sustaining a high-technology civilization*
Anindya Ghosh, Sayam S. Gupta, Michael J. Bartos, Yelda Hangun, Leonard
D. Vuocolo, Bradley A. Steinhoff, Christopher A. Noser, David Horner,
Sherry Mayer, Kevin Inderhees, Colin P. Horwitz, Jonathan Spatz, Alexander
D. Ryabov, Sujit Mondal, and Terrence J. Collins**
Department of Chemistry, Carnegie Mellon University,
4400 Fifth Avenue, Pittsburgh, PA 15206-2683, USA
Abstract: By learning how to balance natural resource limitations
and pollution prevention with economic growth, green chemistry will
become the central science of sustainability. The elimination of persistent
pollutants is vital for a sustainable civilization. To achieve this,
the most important guiding concept is that the elemental composition
of technology should be shifted toward the elemental composition of
biochemistry. Oxidation chemistry is currently a prolific producer of
persistent pollutants. Many arise from the use of chlorine, hypochlorite,
or chlorine dioxide in large-scale oxidation processes. Oxidation chemistry
can be greened by replacing these with catalyzed alternatives based
on Nature's oxidizing agent, hydrogen peroxide. TAML® (TetraAmidoMacrocyclicLigand)
iron catalysts, which were invented at Carnegie Mellon University, are
widely patented and are being developed to activate H2O2
for commercial applications. TAML activators are water-soluble, easy
to use, function well from neutral to basic pH, are not dominated by
nonselective Fenton-like reactivity, are straightforward to synthesize,
work effectively in minute concentrations, enable peroxide processes
to occur at temperatures well below those of the processes targeted
for replacement, and are amenable to modification for capturing novel
selectivities. TAML activators are "dial-a-lifetime" catalysts:
an activator can be chosen exhibiting a lifetime commensurate with the
desired task.
* Lectures presented at the International Symposium
on Green Chemistry, Delhi, India, 10-13 January 2001. Other presentations
are published in this issue, pp. 77-203.
** Corresponding author.