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The Universal Catalyst is in the same league. If some way could be found to make all spontaneous reactions rapid, then all organic matter on our planet, including ourselves, would be converted quickly into carbon dioxide, water, and nitrogen. We can exist in an oxygen atmosphere only because of the existence of activation-energy barriers to reaction. Catalysts
do have a limited use in cleaning up the environment. One line of
approach to automotive pollution is the use of afterburners for
hydrocarbons. To get rid of oxides of nitrogen, catalytic beds are
used to accelerate reactions of the type
Some of the practical difficulties include finding a catalyst that has a long lifetime and is not poisoned easily by lead and other components of commercial gasolines. While we search for the perfect catalyst for nitrogen oxide degradation, it might be well to keep in mind another reaction involving nitrogen:
While this reaction under standard conditions (including 1-molar nitric acid as product) is not quite spontaneous, the nitric acid concentration only has to fall to 0.44 mole liter-1 to make it spontaneous. Were it not for the high activation energy of this reaction, all of the water vapor, all of the oxygen, and a good part of the nitrogen, would be swept from our atmosphere, and the oceans would become a solution of dilute nitric acid.1 We had better be sure that the "perfect catalyst" for the smog reaction does not also catalyze nitrogen reactions in general!
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