| TECHNOLOGY |
Co says more progress in precious metal cost cutting can still be made. In the process Co is rankling competitors, which view the company as a maverick outfit that has nothing new to offer.
The catalyst companies "have done good work getting PGM down by 50% in the last five to seven years, which was a huge step," says CONTACT. "But things have plateaued, with more good work being done relatively slowly." Co.`s breakthrough is the use of mixed-metal oxides, particularly perovskite structures, as the main catalyst in catalytic converters. Small amounts of precious metals are incorporated into the structures for useful synergies, he adds. There are dozens of possible mixed-metal oxide structures, incorporating 28 different metals. CONTACT notes that in the high, 900 to 1,000 °C heat found in exhaust systems, mixed-metal oxides incorporating precious metals sinter together and quickly deteriorate. "The problem with mixed-metal oxides that people kept bumping into was that the total stability was very bad, which meant that they grow to be very large crystallites that don't have much activity anymore," he says. The solution to this problem, CONTACT says, is to keep the fragments of mixed-metal oxides separated by interspersing them with different materials, making a product he calls a multiphase catalyst. "It's a very harsh and a very crude solution, but it does the trick to stop the sintering mechanism."
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