By Janet Raloff
A novel type of catalytic converter could be available within a year, just in time to help some trucks meet new standards limiting emissions of smog-generating nitrogen oxides.
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By next year, heavy-duty diesel trucks will be permitted to spew no more than 10 percent of the amounts of NOx permitted in 1990. Currently a liquid-urea–based catalytic converter system is available to clean up NOx, but it’s messy and cumbersome. Within a year, however, a no-muss alternative could be ready to rumble down the interstates: a catalytic converter that uses onboard diesel fuel as its additive, not urea.
Both catalyst systems convert nasty NO