The science of catalytic converters, part 1 of why catalytic converters are being stolen

Yesterday, I shared one story I tell my students in which bags are best and worst for the environment. Today, I'm sharing another, about the earth materials, mostly metals, used to make automobiles. I focus on three parts in particular, catalytic converters, air bags, and wheels, because the high-value metals in them increase their costs and make them attractive to thieves.* The prices of the metals in catalytic converters have shot up recently, leading to a rising tide of thefts.

I'll get to the economics of this phenomenon tomorrow. Today, I'm concentrating on the science, particularly the chemistry and engineering, of catalytic converters along with the legal and regulatory changes that made them mandatory on cars in the U.S. and elsewhere, beginning with Verge Science's This metal is more valuable than gold.

The theft of catalytic converters is on the rise due to the value of the precious metals they contain. One of these metals, palladium, is now more valuable than gold and is crucial in helping to clean up toxic emissions. As soaring demand creates a palladium crunch, the race is on to find new alternatives — or rethink how we use palladium in the future.

This video does a good job of explaining how the platinum-group metals work in catalytic converters and what kind of scientific and engineering solutions can reduce the amount of palladium, platinum, and rhodium used while still achieving the same pollution control. It's a little short on the personal angle except for the very end. For that, I turn to PBS Digital's Reactions Catalytic Converter Stolen? Here's Why.

Catalytic converter theft is on the rise, and that’s partly because of their chemistry.

The Reactions video manages to combine a more personal tone with even more science. That makes it a good candidate to share with my students, although I'm tempted to share both.

That's the science side of the story, along with a dose of the legal and regulatory history behind mandating catalytic converters to reduce air pollution. Stay tuned for part 2 tomorrow, which will concentrate on the economics and crime prevention aspects of the issue.

*I focus on these three parts because the car next to mine had them stripped out of it, along with the sound system, and the car left on cinder blocks when I taught in the Detroit Public Schools 21 years ago. My poor colleague was in shock when she discovered the theft. Fortunately, I drove the worst car in the lot — the custodians made fun of it — and the thieves left it alone. Lucky me.