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