About Catalysis

Catalysts, in the definition developed by Berzelius and others in the last century, are materials which change the rate of attainment of chemical equilibrium without themselves being changed or consumed in the process.

Catalysis is an astonishing phenomenon. Some catalysts achieve astonishing activities, so that very small quantities of catalyst can convert thousands or millions of times their own weight of chemicals. Equally significant, however, is selectivity; usually thought of in terms of a catalyst accelerating one of a number of competing reactions, but also possible by virtue of a catalyst selecting one reagent out of a complex mixture.

Catalysis is the key to both life and lifestyle. It is an essential technology for chemical and materials manufacturing, for fuel cells and other energy conversion systems, for combustion devices, and for pollution control systems. Catalysts are widely used in food processing, and enhance the performance of other consumer products such as laundry detergents. The possibility of analysing and ultimately manipulating genes rests on the catalytic properties of RNA to replicate molecules containing biological information. New sensor systems use catalytic surfaces to detect specific molecules and announce their presence through the heat of a vigorous catalytic reaction. And while the tendency is to think of catalysis as a phenomenon for making things happen, the basis of many valuable drugs is the opposite phenomenon; Viagra and Quinapril combat impotence and hypertension by inhibiting enzymes, respectively PDE-V, a phosphodiesterase which breaks down the NO messenger cGMP, and ACE, the Angiotensin-Converting Enzyme.

The economic contribution from catalysis is as remarkable as the phenomenon itself. Estimates from just four years ago that 35% of global GDP depends on catalysis missed much of the emergent genetic business. Confining the analysis to the chemicals industry, with global sales of perhaps US$1.5 x 1012 the proportion of processes using catalysts is 80% and increasing. The catalyst market itself is US$1010, so that catalysis costs are much less than 1% of the sales revenue from the products which they help create. Small wonder that the catalyst market is increasing at 5% per annum.

The terms “catalyst” and “catalysis” have also translated from the world of science to everyday cliché. Our western society places a high value on the power to induce change, under the descriptor “progress”, and it is small wonder that “catalyst” is a tradename chosen for wine, perfume, magazines, management consultancies and advertising agencies. There is even a breed of comic-book superheroes.

The eastern tradition is different. Rather than depicting a catalyst as an agent of rapid breakdown and change, the Chinese characters for “catalyst” also apply to “marriage broker”.

This is a subtle and perceptive appreciation of how catalysts work. It also seems most appropriate given that the successful creation and application of catalytic processes is genuinely multidisciplinary. On a technical level it requires skills in chemistry, chemical engineering, materials technology, as well as the economics and practicalities of manufacturing processes. And it can best be induced by active and strategic collaboration between industry, universities and government.

Chris Adams
Institute of Applied Catalysis
See also: “Catalysing Business” by C J Adams, Chemistry and Industry, 1999, pp740-743