New Catalytic Converters Can Make Diesel Engines Environmentally Friendly
Thanks to new research by the General Motors Global Research and Development, Chemical Sciences and Materials Systems Lab, the hurdles facing diesel-powered vehicle engines regarding their inability to pass US emissions standards may have a solution at last. A new catalytic converter is being prepared for testing that blends palladium -- which is much cheaper than previous used platinum-- and the mineral perovskite "to improve the low-temperature performance," says Wei Li, the chief engineer on the project.
There are concerns about the environmental impact of this converter, however, and a chemical engineer at the Institute of Chemical Technology in Prague, Jan Stepanek, commented that "due to automotive catalyst decay, there are appreciable concentrations of precious metals near roads." So far this diesel catalytic converters posed no threat because the platinum used was very stable. But the introduction of strontium to the design has raised concerns that aging catalytic converters could leak this potentially hazardous material into the water table. Also, the perovskite reacts to the sulfur content in the diesel, and can be deactivated if the converter reaches temperatures over 700 degrees Centigrade.