Catalytic converter theft

Demand for precious metals and parts that contain them is rising
If you run a petrol car you need to be aware of the risk of catalytic converter theft, particularly if your car has large ground clearance. Thieves are targetting catalysts – located in the exhaust system under the vehicle – because of the high vlaue of the precious metals they contain.

In these harder times and with precious metal prices rising steadily, the demand for parts that contain them is rising. As a result, the risk of theft of catalytic converters is on the increase again.

Catalytic converters (CATs) have been fitted in the exhaust of the majority of petrol cars manufactured since 1992 and by chemical reaction substantially reduce harmful pollutants from the exhaust.

The metal case of the CAT contains a ceramic honeycombed structure providing a massive surface area across which the exhaust gases flow.

Precious metals – platinum, palladium and rhodium – are coated onto this ceramic structure as catalysts (a catalyst modifies and increases the rate of a chemical reaction without being consumed itself) for the reactions that 'clean' the exhaust;

Oxidising (adding oxygen) carbon monoxide and unburnt hydrocarbons to form carbon dioxide and water, and
Reducing (remove oxygen) from other gases such as oxides of nitrogen
Theft
The start of the credit crunch in 2008 and high prices for precious metals resulted in a noticeable increase in thefts of catalytic converters. Thieves simply cut the catalytic converter from the exhaust pipe of a parked car and sell them on to scrap metal dealers.

Taller vehicles (4x4s) are particularly vulnerable as the converters are more accessible. Because they tend to have larger engines, they contain more of the precious metals too.

The ceramic honeycomb has to undergo a chemical process known as 'carbochlorination' to recover the precious metals it contains – generally abroad in countries such as China, Poland, Canada and Latvia.

Once an unmarked converter has been removed from a vehicle it's quite difficult to match it to that vehicle as there aren't any distinguishing marks.